• Title/Summary/Keyword: tool trajectory

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The Study on Ultra-Precision Cutting Characteristics Evaluation of Non-Ferrous Metals Using Attractor Quadrant Method (어트랙터 사분면법을 이용한 비철금속의 초정밀 절삭특성 평가에 관한 연구)

  • 고준빈;김건희;윤인식
    • Journal of the Korean Society for Precision Engineering
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    • v.20 no.6
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    • pp.20-26
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    • 2003
  • This study proposes the construction of attractor quadrant method for high-precision cutting characteristics evaluation of non-ferrous metals. Also this paper aims to find the optimal cutting conditions of diamond turning machine by measuring surface form and roughness to perform the cutting experiment of non-ferrous metals, which are aluminum, with diamond tool. As well, according to change cutting conditions such as feed rate, using diamond turning machine to Perform cutting Processing, by measuring cutting force and surface roughness and according to cutting conditions the aluminum about cutting properties. Trajectory changes in the attractor indicated a substantial difference in fractal characteristics and attractor quadrant characteristics. In quantitative quadrant feature extraction, 1,309 point in the case of A17075 (one quadrant) and 1,406 point (one quadrant) in the case of brass were proposed on the basis of attractor reconstruction. Proposed attractor quadrant method can be used for high-precision cutting characteristics evaluation of non-ferrous metals.

Study on the characteristics of miniaturized free electron laser module (초소형 자유전자 레이저 모듈에 대한 특성 연구)

  • Kim, Young-Chul;Ahn, Seong-Joon;Kim, Ho-Seob;Kim, Dae-Wook;Ahn, Seung-Joon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.9 no.6
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    • pp.1607-1613
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    • 2008
  • We investigated the miniaturized free electron laser(FEL) module based on microcolumn. The miniaturized FEL is composed of two parts: electron generation part and radiation emission part. The radiation emission part, called wiggler, consists of a grid plate. While the electrons are passing through the wiggler, electron trajectory shows sinusoidal curve caused by the periodically applied voltage on the grid, and then it give rise to radiation emission. We analyzed the wiggler parameters, grid width, depth, period, applied voltage and the pair wiggler space using 2-D simulation tool.

Curriculum Design for Digital Fashion Film Making (디지털 패션필름 제작 교과에 관한 커리큘럼 개발)

  • Mikyung Kim;Eunhyuk Yim
    • Fashion & Textile Research Journal
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    • v.25 no.4
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    • pp.429-438
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    • 2023
  • In the 21st century fashion industry, the rise of digital environments has transformed it into a dynamic medium, expanding the horizons of media utilization. Consequently, digital fashion film has emerged as a pivotal tool for fashion communication. Functioning as a visual expression medium, fashion film animates fashion concepts into immersive moving images. Proficiency in digital fashion communication has become imperative, considering the attributes of fashion media. Notably, the role of creative directors in ensuring coherent communication across diverse fashion media platforms has gained prominence, underscoring the need for systematic fashion education to nurture specialized talent. This study, therefore, devised a comprehensive curriculum amalgamating fashion communication and practical digital media skills, implemented within fashion major courses. Through this approach, students gained experimental media proficiency and explored innovative approaches to crafting fashion films that eloquently convey fashion narratives. The participants were exposed to the entire spectrum of fashion media production, encompassing digital storytelling, fashion film conceptualization, filming techniques, meticulous editing, and adept utilization of special effects technology. The study's pedagogical strategy, characterized by a focused learning trajectory, garnered significant acclaim. In essence, this study holds significance by formulating a curriculum that nurtures the imaginative and pragmatic aptitudes of fashion majors, immersing them in the dynamic realm of rapidly evolving digital fashion films and their integration with fashion content.

Development of a Real-Time Position Tracking System for a Manufacturing Process Based on a UWB Sensor Using a Kalman Filter (칼만필터를 적용한 UWB 센서기반 제조업 조립공정작업의 실시간 위치추적 시스템 개발)

  • Jeong, Seung-Hyun;Choi, Deuk-Sung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.2
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    • pp.627-633
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    • 2020
  • Assembly process data can be gathered in real time in a manufacturing execution system (MES) server using proximity sensors, barcodes, RFID, ZigBee, Bluetooth, wireless sensor networks, etc. Although this is suitable for identifying process flow and checking production progress, it is difficult to trace the location of individual workers in real time for missing work or trajectories within the work area. To overcome this, the location and trajectory of the working tool can be analyzed in real time through a position tracking system of an operator's working tool. It can instruct the operator to perform a consistent working process. Productivity and quality improvement can be achieved by an alarming or blocking operator with possible assembly defects during the assembly process in real time. To this end, we developed a real-time tool position-tracking sensor system based on Ultra Wide Band (UWB) trilateration using a Kalman filter to eliminate mechanical vibration and radio communication noise.

Re-entry Survivability and On-Ground Risk Analysis of Low Earth Orbit Satellite (저궤도 위성의 대기권 재진입 시 생존성 및 피해확률 분석)

  • Jeong, Soon-Woo;Min, Chan-Oh;Lee, Mi-Hyun;Lee, Dae-Woo;Cho, Kyeum-Rae;Bainum, Peter M.
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.42 no.2
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    • pp.158-164
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    • 2014
  • LEO(Low Earth Orbit) Satellite which is discarded should be reentered to atmosphere in 25 years by '25 years rule' of IADC(Inter-Agency Space Debris Coordination Committee) Guidelines. If the parts of satellite are survived from severe aerothermodynamic condition, it could damage to human and property. South Korea operates KOMPSAT-2 and STSAT series as LEO satellite. It is necessary to dispose of them by reentering atmosphere. Therefore this paper analyze the trajectory, survivability, casualty area and casualty probability of a virtual LEO satellite using ESA(European Space Agency)'s DRAMA(Debris Risk Assesment and Mitigation Analysis) tool. As a result, it is noted that casuality area is $15.2742m^2$ and casualty probability is 5.9614E-03 then will be survived 198.831kg.

The Effect of Elastic Therapeutic Taping on Lower Limb Kinematics during a Cross Cutting Movement from Landing in Subjects with Chronic Ankle Instability (탄력 테이핑이 만성 발목 불안정 환자의 착지 후 방향 전환 시 하지 관절 움직임에 미치는 영향)

  • Jo, Tae-Seong;Kim, Tack-Hoon;Choi, Houng-Sik;Roh, Jung-Suk
    • Journal of the Korean Society of Physical Medicine
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    • v.12 no.4
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    • pp.1-9
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    • 2017
  • PURPOSE: This study investigated the effect that an elastic therapeutic taping treatment given to patients with chronic ankle instability had on the vertical ground reaction force, center of pressure, and range of motion in the ankle, knee and hip joints, during a Cross-cutting movement from landing. METHODS: This study analyzed 12 able-bodied adults and 12 patients with chronic ankle instability classified by using the Cumberland tool in the motion analysis laboratory, Hanseo University. The experiment was conducted under two conditions elastic taping and no treatment. In order to analyze the difference between the groups. An independent t-test was performed at p>.01. RESULTS: Plying an elastic therapeutic taping to the patients with chronic ankle instability significantly decreased the range of joint motion in the inversion of the ankle joint, the flexion of the knee joint, and the flexion and internal rotation of the hip joint during a cross-cutting movement from landing in comparison with the able-bodied adults p<.01. This restriction in the range of motion decreased the center-of-pressure trajectory length of patients with chronic ankle instability p>.01. CONCLUSION: An elastic therapeutic taping treatment given to patients with chronic ankle instability causes ankle stability to increase during a cross-cutting movement from landing.

Analysis of the Macroscopic Traffic Flow Changes using the Two-Fluid Model by the Improvements of the Traffic Signal Control System (Two-Fluid Model을 이용한 교통신호제어시스템 개선에 따른 거시적 교통류 변화 분석)

  • Jeong, Yeong-Je;Kim, Yeong-Chan;Kim, Dae-Ho
    • Journal of Korean Society of Transportation
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    • v.27 no.1
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    • pp.27-34
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    • 2009
  • The operational effect of traffic signal control improvement was evaluated using the Two-Fluid Model. The parameters engaged in the Two-Fluid Model becomes food indicators to measure the quality of traffic flow due to the improvement of traffic signal operation. A series of experiment were conduced for the 31 signalized intersections in Uijeongbu City. To estimate the parameters in the Two-Fluid Model the trajectory informations of individual vehicles were collected using the CORSIM and Run Time Extension. The test results showed 35 percent decrease of average minimum trip time per unit distance. One of the parameters in the Two-Fluid Model is a measure of the resistance of the network to the degraded operation with the increased demand. The test result showed 28 percent decrease of this parameter. In spite of the simulation results of the arterial flow, it was concluded that the Two-Fluid Model is useful tool to evaluate the improvement of the traffic signal control system from the macroscopic aspect.

Application of MODIS Satellite Observation Data for Air Quality Forecast (MODIS 인공위성 관측 자료를 이용한 대기질 예측 응용)

  • Lee, Kwon-Ho;Lee, Dong-Ha;Kim, Young-Joon
    • Journal of Korean Society for Atmospheric Environment
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    • v.22 no.6
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    • pp.851-862
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    • 2006
  • Satellites have been valuable tool for global/regional scale atmospheric environment monitoring as well as emission source detection. In this study, we present the results of application of satellite remote sensing data for air quality forecast in Seoul metropolitan area. AOT (Aerosol Optical Thickness) data from TERRA/MODIS (Moderate Resolution Imaging Spectre-radiometer) satellite were compared to ground based $PM_{10}$ mass concentrations, and used to estimate the possibility of the aerosol forecasting in Seoul metropolitan area. Although correlation coefficient (${\sim}0.37$) between MODIS AOT products and surface $PM_{10}$ concentration data was relatively low, there was good correlation between MODIS AOT and surface PM concentration under certain atmospheric conditions, which supports the feasibility of using the high-resolution MODIS AOT for air quality forecasting. The MODIS AOT data with trajectory forecasts also can provide information on aerosol concentration trend. The success rate of the 24 hour aerosol concentration trend forecast result was about 75% in this study. Finally, application of satellite remote sensing data with ground-based air quality observations could provide promising results for air quality monitoring and more exact trend forecast methodology by high resolution satellite data and verification with long term measurement dataset.

Identification of sperm motility subpopulations in Gyr falcon (Falco rusticolus) ejaculate: a tool for investigating between subject variation

  • Seyedasgari, Fahimeh;Asadi, Behnam;Sebastyen, Sandor;Guillen, Roberto
    • Journal of Animal Reproduction and Biotechnology
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    • v.37 no.3
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    • pp.193-201
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    • 2022
  • Subgroups of sperm which share similar motility features documented in mammals indicate between-subject variations that might be related to fertilizing potential of the respective ejaculates. The objectives of this study were to define subpopulations of motile sperm in Gyr falcon semen using kinematic parameters driven by Computer Assisted Semen Analysis (CASA) and to investigate the subject-related variations in these subpopulations. A total of 24 fresh ejaculates from 6 falcons were used to assign each of the 20473 sperms into 3 subpopulations by a multivariate cluster analysis. The proportion of sperms in different sub-populations were compared among subjects by a generalized linear model and repeatability of sperm frequency in different subpopulations was investigated by corelation analysis. The resulting 3 categories of sperm indicated significant differences in all kinematic parameters (p < 0.05). Subpopulation 1 (15.91%) contained sperms with the highest velocity and progressiveness of movement trajectory while subpopulation 3 (6.4%) included the least progressively motile sperms. Proportion of rapid and medium progressive sperm were consistently higher in the ejaculate of three falcons compared to the two other birds which also had the highest proportion of slow non-progressive sperms (p < 0.05). Respective proportion of sperms in each subpopulations indicated significant repeatability over multiple measurements (p < 0.05). In conclusion, subpopulations of motile sperm in Gyr falcon can be identified using kinematic parameters generated by CASA. Individual differences in the proportion of these subpopulations might have potential application for identifying the males with higher fertilizing capacity.

Estimation of Domestic Aircraft Fuel Consumption and Improved Accuracy (국내선 항공기 연료소모량 추정및 정확도 향상)

  • HyeJin Hong;JiHun Choi;SungKwan Ku
    • Journal of Advanced Navigation Technology
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    • v.27 no.5
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    • pp.649-657
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    • 2023
  • ICAO adopted the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) at the 39th General Assembly in 2016, and 115 countries, including South Korea, expressed their intention to participate in CORSIA as of January 1, 2023. Since carbon generated in the aviation industry is mainly caused by greenhouse gases emitted from aircraft engines, fuel consumption must be reduced to reduce carbon emissions. Prior research, such as simulation, is essential to predict the effectiveness of each plan and to make decisions about its implementation. High-quality data is needed to derive accurate results, but it has been difficult to secure actual fuel consumption data, as they are considered to be classified airline data. Therefore, in this paper, after establishing a model that estimates fuel consumption based on actual fuel consumption data, the model is to be advanced to improve its accuracy.