• Title/Summary/Keyword: airplane

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Pregnancy Rate of In Vitro Produced Korean Cattle Embryos according to Transport Time Course

  • Park, Hyo-Young;Kim, Eun-Young;Kim, Young-Hun;Mun, Seong-Ho;Oh, Chang-Eon;Han, Young-Joon;Kim, Nam-Hyung;Lee, Sung-Soo;Ko, Moon-Suck;Riu, Key Zung;Park, Se-Pill
    • Reproductive and Developmental Biology
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    • v.33 no.4
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    • pp.257-262
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    • 2009
  • This study was to investigate pregnancy rate of IVM/IVF/IVC Korean cattle (registered in government) embryos according to transport time course. For the production of embryos, oocytes recovered from slaughtered excellent grade cow and highly motile frozen-thawed bull semen (purchased from LIMC, KPN#497) was used. In vitro produced embryos were cultured in CR1aa medium for 8 days and some of them were frozen. The rate of average cleavage (>2-cell) was 83.0% (308/371) and blastocyst rate at day 8 was 34.7% (107/308). Among in vitro produced blastocyst embryos at day 8, most healthy embryos were freshly transferred on production day and some frozen embryos were direct transferred on appropriate day. These embryos were produced in a laboratory, embryo transfer (ET) was planned in 10 areas of the remote island (Jeju) from the laboratory by airplane. Thus, we examined the pregnancy rate in recipient cow according to embryo of transport time course before ET. From embryo transferred 44 recipient cows, overall pregnancy was 40.9% (18/44), these 18 cows were all calved [single, 94% (17/18); twin, 6% (1/18)] and total embryo implantation rate was 26% (19/66). Comparing transport time in the base of 6 hr, pregnancy rate in ET group required less 4 hr (60%, 9/15) was significantly higher than that required more 6 hr (26.3%, 5/19). In direct ET of freezing embryos, the pregnancy rate was 40% (4/10). However, it was difficult to find the meaning of temperature, pH and corpus luteum quality of recipients on comparison of pregnancy rate. When the cell death level of embryos according to storage time in thermos (straw container) before ET was measured by TUNEL staining, apoptotic index was increased with storage time-dependent. These results demonstrated that long distance transfer of IVM/IVF/IVC embryos is possible and the time of embryo transport is very important for the pregnancy rate on field trial.

Potential Use of 3D Course Material as a Pedagogical Tool for Laboratory Courses with respect to Assembly/Disassembly of the Combustion Chamber in Vocational High Schools (항공고등학교 실습교육에서 연소실 분해 조립을 중심으로 고찰한 3D 학습 자료의 활용 방안)

  • Lee, Tae-gyoon;Kim, Jong-Seong
    • Journal of Internet Computing and Services
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    • v.17 no.3
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    • pp.33-43
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    • 2016
  • In this study, 3D-image based course material has been suggested as a potential pedagogical tool for laboratory courses for aviational maintenance in vocational high schools. With a special focus on assembly/disassembly of the combustion chamber, 3D contents described here are created by Soildworks 2014 based on the textbook widely used in aviational high schools. By analyzing several textbooks currently adopted at various schools, we have clearly shown that the current text-based teaching method is far from being effective regarding providing adequate learning environment for high school students who study aviational maintenance. From the analysis of the conventional textbooks, it is seen that it is urgent that we should come up with more effective and efficient way of teaching methods for these topics at vocational high schools. Using Solidworks, we have developed very vivid 3D image-based course material for topics related to a combustion chamber in the airplane. Newly developed 3D material is seen to clearly show step by step procedures of assembly and disassembly of the combustion chamber which has crucial importance in the aviational laboratory courses. Especially the transparent feature in Solidworks could make it possible to observe the parts covered by outer casing, which can not be seen even in any laboratory class with real objects. 3D animated views could provided unprecedented learning environment for students to acquire core knowledge with ease for the maintenance of a combustion chamber. In order to provide easy access for students to this 3D-based course material, the exclusive viewer is also developed using MS office powerpoint 2007. An example of a learning plan using 3d course material is suggested as well.

The Historical Geography of Sacheon Bay Region -with Special Reference to Transportation, Fishery, and Industry- (사천만 연안의 지역 변화에 관한 연구 -교통.수산업.공업 기능의 변화를 중심으로-)

  • Lee, Jeon;Kwak, Chul-Hong
    • Journal of the Korean association of regional geographers
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    • v.5 no.2
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    • pp.119-132
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    • 1999
  • The Korean Peninsula, jutting southward from the Asian mainland into the Pacific Ocean, is surrounded by numerous bays and islands on three sides. The study area of this research is the coastal area surrounding the Sacheon Bay, which is located in the mid-southern tip of the peninsula. Historically, the bay region took the role of the main gate leading to the western part of Kyung-nam Do(Province) due to the fact that the bay is the nearest coast to Chinju, the central city of the province. The Sacheon Bay had provided important sea routes from the old days until the early twentieth century. Because of the bay's sea routes, the bay region has been militarily of great significance. Recently, road/rail/highway/airplane transportation functions have become gradually increased but sea transportation function has been decreased in the region. As the Sacheon Bay was rich in fishery resources, dozens of fishing villages in the bay region depended on fishery and marine product industries for long years. But the inflow of the fresh water used to cause serious damage to the fishing industry in the bay region after a drainage canal from the Nam River was constructed in 1969. As a result, the industry has dwindled gradually for last decades. Recently, a couple of industrial parks were constructed along the coast and many manufacturing factories were built on the parks. It has been expected that many jobs lost in fishery and agriculture are replaced by new opportunities in industry. More than half of the workers employed in the parks' factories commute from the city of Chinju. It is asserted in this paper that the transportation, fishery, manufacturing, and tourism functions of the Sacheon Bay region are closely associated with. The characteristics of the region can be well understood through the functional changes and associations.

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Drone-based smart quarantine performance research (드론 기반 스마트 방재 방안 연구)

  • Yoo, Soonduck
    • The Journal of the Convergence on Culture Technology
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    • v.6 no.2
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    • pp.437-447
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    • 2020
  • The purpose of this study is to research the countermeasures and expected effects through the use of drones in the field of disaster prevention as a drone-based smart quarantine performance method. The environmental, market, and technological approaches to the review of the current quarantine performance task and its countermeasures are as follows. First, in terms of the environment, the effectiveness of the quarantine performance business using drone-based control is to broaden the utilization of forest, bird flu, livestock, facility areas, mosquito larvae, pests, and to simplify and provide various effective prevention systems such as AI and cholera. Second, in terms of market, the standardization of livestock and livestock quarantine laws and regulations according to the use of disinfection and quarantine missions using domestic standardized drones through the introduction of new technologies in the quarantine method, shared growth of related industries and discovery of new markets, and animal disease prevention It brings about the effect of annual budget savings. Third, the technical aspects are (1) on-site application of disinfection and prevention using multi-drone, a new form of animal disease prevention, (2) innovation in the drone industry software field, and (3) diversification of the industry with an integrated drone control / control system applicable to various markets. (4) Big data drone moving path 3D spatial information analysis precise drone traffic information ensures high flight safety, (5) Multiple drones can simultaneously auto-operate and fly, enabling low-cost, high-efficiency system deployment, (6) High precision that this was considered due to the increase in drone users by sector due to the necessity of airplane technology. This study was prepared based on literature surveys and expert opinions, and the future research field needs to prove its effectiveness based on empirical data on drone-based services. The expected effect of this study is to contribute to the active use of drones for disaster prevention work and to establish policies related to them.

Patent Valuation for Fair Royalty Distribution in Patent Pool (특허풀에서의 공평한 로열티 분배를 위한 특허가치평가)

  • Kim, Young-Ki;Park, Seong-Taek;Lee, Seung-Jun
    • Journal of Digital Convergence
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    • v.8 no.1
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    • pp.41-53
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    • 2010
  • In this paper, we discuss patent pool and a patent valuation scheme for fair royalty distribution among the patents in a pool. In the knowledge-based economy, intellectual capital-the accumulation of technology and know-how-is recognized as the most important source of company's competitive advantage and economic growth. By providing exclusive rights to patent holders, the patent system aims to encourage innovation-invention & commercialization of new technologies-in order to raise the standard of living. However, drawbacks of patent system, which occur as the number of patents issued increases rapidly and patent ownership is fragmented, may slow down the innovation efforts seriously. A promising solution is the patent pool approach, which was for instance employed by the U.S. congress during World War I to free the airplane manufacturers from the patent tangle by letting them license all the patents for a fee. It is necessary to figure out relative technological contribution of patent for fair distribution of royalty revenues among patent holders. The Rating/Ranking Method seems to fit to that valuation purpose. We examined technology valuation models from various organizations and selected a set of more influential valuation factors which can be incorporated as scoring criteria in the Rating/Ranking Method.

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Analytical Assessment of Blast Damage of 270,000-kL LNG Storage Outer Tank According to Explosive Charges (270,000 kL급 LNG 저장 탱크 외조의 폭발량에 따른 손상도 해석적 평가)

  • Kim, Jang-Ho Jay;Choi, Seung-Jai;Choi, Ji-Hun;Kim, Tae-Kyun;Lee, Tae-Hee
    • Journal of the Korea Concrete Institute
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    • v.28 no.6
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    • pp.685-693
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    • 2016
  • The outer tank of a liquefied natural gas (LNG) storage tank is a longitudinally and meridionally pre-stressed concrete (PSC) wall structure. Because of the current trend of constructing larger LNG storage tanks, the pre-stressing forces required to increase wall strength must be significantly increased. Because of the increase in tank sizes and pre-stressing forces, an extreme loading scenario such as a bomb blast or an airplane crash needs to be investigated. Therefore, in this study, the blast resistance performance of LNG storage tanks was analyzed by conducting a blast simulation to investigate the safety of larger LNG storage tanks. Test data validation for a blast simulation of reinforced concrete panels was performed using a specific FEM code, LS-DYNA, prior to a full-scale blast simulation of the outer tank of a 270,000-kL LNG storage tank. Another objective of this study was to evaluate the safety and serviceability of an LNG storage tank with respect to varying amounts of explosive charge. The results of this study can be used as basic data for the design and safety evaluation of PSC LNG storage tanks.

Comparison between Numerical Results of 1D Beam and 2D Plane Stress Finite Element Analyses Considering Aspect Ratio of Cantilever Beams (캔틸레버보의 형상비에 따른 1차원 보와 2차원 평면응력 유한요소해석 결과의 비교)

  • Kang, Yoo-Jin;Sim, Ji-Soo;Cho, Hae-Sung;Shin, Sang-Joon
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.28 no.5
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    • pp.459-465
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    • 2015
  • There exist different kinds of aircrafts, such as conventional airplane, rotorcraft, fighter, and unmanned aerial vehicle. Their shape and feature are dependent upon their own assigned mission. One of the fundamental analyses performed during the aircraft design is the structural analysis. It becomes more complicated and requires severe computations because of the recent complex trends in aircraft structure. In order for efficiency in the structural analysis, a simplified approach, such as equivalent beam or plate model, is preferred. However, it is not clear which analysis will be appropriate to analyze the realistic configuration, such as an aircraft wing, i.e., between an equivalent beam and plate analysis. It is necessary to assess the limitation for both the one-dimensional beam analysis and the two-dimensional plate theory. Thus, in this paper, the static structural analysis results obtained by EDISON solvers were compared with the three-dimensional results obtained from MSC NASTRAN. Before that, EDISON program was verified by comparing the results with those from MSC NASTRAN program and other analytic solutions.

Experimental Assessment of Tensile Failure Characteristic for Advanced Composite Laminates (첨단복합재료 적층판의 인장 파손특성 시험적 평가)

  • Lee, Myoung Keon;Lee, Jeong Won;Yoon, Dong Hyun;Kim, Jae Hoon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.41 no.10
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    • pp.959-965
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    • 2017
  • In recent years, major airplane manufacturers have been using the laminate failure theory to estimate the strain of composite structures for airplanes. The laminate failure theory uses the failure strain of the laminate to analyze composite structures. This paper describes a procedure for the experimental assessment of laminate tensile failure characteristics. Regression analysis was used as the experimental assessment method. The regression analysis was performed with the response variable being the laminate failure strain and with the regressor variables being two-ply orientation ($0^{\circ}$ and ${\pm}45^{\circ}$) variables. The composite material in this study is a carbon/epoxy unidirectional (UD) tape that was cured as a pre-preg at $177^{\circ}C(350^{\circ}F)$. A total of 149 tension tests were conducted on specimens from 14 distinct laminates that were laid up at standard angle layers ($0^{\circ}$, $45^{\circ}$, $-45^{\circ}$, and $90^{\circ}$). The ASTM-D-3039 standard was used as the test method.

Analysis of Two-Way Fluid-Structure Interaction and Local Material Properties of Brazed Joints for Estimation of Mechanical Integrity (관형 열교환기의 기계적 건전성 확보를 위한 유체-고체 연성해석과 브레이징 접합부의 국부적 물성분포 분석)

  • Kang, Seok Hoon;Park, Sang Hu;Min, June Kee;Jeong, Ho Sung;Son, Chang Min;Ha, Man-Young;Cho, JongRae;Kim, Hyun Jun
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.37 no.1
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    • pp.9-16
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    • 2013
  • Recent years have witnessed a strong need for eco-friendly and energy-efficient systems owing to global environmental problems. A heat exchanger is a well-known mechanical rig that has long been used in many energy systems. The use of a heat exchanger in an airplane engine has been attempted. In this case, the heat exchanger should be redesigned to be compact, lightweight, and highly reliable, and the issue of mechanical integrity gains importance. Therefore, in this study, we proposed a method for evaluating the mechanical integrity of a tube-type heat exchanger. A U-shaped single tube was used as an example, and its behavior and stress distribution were studied using fluid-structure interaction (FSI) analysis.

Individual Ortho-rectification of Coast Guard Aerial Images for Oil Spill Monitoring (유출유 모니터링을 위한 해경 항공 영상의 개별정사보정)

  • Oh, Youngon;Bui, An Ngoc;Choi, Kyoungah;Lee, Impyeong
    • Korean Journal of Remote Sensing
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    • v.38 no.6_1
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    • pp.1479-1488
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    • 2022
  • Accidents in which oil spills occur intermittently in the ocean due to ship collisions and sinkings. In order to prepare prompt countermeasures when such an accident occurs, it is necessary to accurately identify the current status of spilled oil. To this end, the Coast Guard patrols the target area with a fixed-wing airplane or helicopter and checks it with the naked eye or video, but it was difficult to determine the area contaminated by the spilled oil and its exact location on the map. Accordingly, this study develops a technology for direct ortho-rectification by automatically geo-referencing aerial images collected by the Coast Guard without individual ground reference points to identify the current status of spilled oil. First, meta information required for georeferencing is extracted from a visualized screen of sensor information such as video by optical character recognition (OCR). Based on the extracted information, the external orientation parameters of the image are determined. Images are individually orthorectified using the determined the external orientation parameters. The accuracy of individual orthoimages generated through this method was evaluated to be about tens of meters up to 100 m. The accuracy level was reasonably acceptable considering the inherent errors of the position and attitude sensors, the inaccuracies in the internal orientation parameters such as camera focal length, without using no ground control points. It is judged to be an appropriate level for identifying the current status of spilled oil contaminated areas in the sea. In the future, if real-time transmission of images captured during flight becomes possible, individual orthoimages can be generated in real time through the proposed individual orthorectification technology. Based on this, it can be effectively used to quickly identify the current status of spilled oil contamination and establish countermeasures.