• Title/Summary/Keyword: flight quality

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Evaluation of TOF MR Angiography and Imaging for the Half Scan Factor of Cerebral Artery (유속신호증강효과의 자기공명혈관조영술을 이용한 뇌혈관검사에서 Half Scan Factor 적용한 영상 평가)

  • Choi, Young Jae;Kweon, Dae Cheol
    • Journal of the Korean Magnetics Society
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    • v.26 no.3
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    • pp.92-98
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    • 2016
  • To aim of this study was to assess the full scan and half scan of imaging with half scan factor. Patients without a cerebral vascular disease (n = 30) and were subject to the full scan half scan, and set a region of interest in the cerebral artery from the three regions (C1, C2, C3) in the range of 7 to 8 mm. MIP (maximum intensity projection) to reconstruct the images in signal strength SNR (signal to noise ration), PSNR (peak signal noise to ratio), RMSE (root mean square error), MAE (mean absolute error) and calculated by paired t-test for use by statistics were analyzed. Scan time was half scan (4 minutes 53 seconds), the full scan (6 minutes 04 seconds). The mean measurement range (7.21 mm) of all the ROI in the brain blood vessel, was the SNR of the first C1 is completely scanned (58.66 dB), half-scan (62.10 dB), a positive correlation ($r^2=0.503$), for the second C2 SNR is completely scanned (70.30 dB), half-scan (74.67 dB) the amount of correlation ($r^2=0.575$), third C3 of a complete scan SNR (70.33 dB), half scan SNR (74.64 dB) in the amount of correlation between the It was analyzed with ($r^2=0.523$). Comparative full scan with half of SNR ($4.75{\pm}0.26dB$), PSNR ($21.87{\pm}0.28dB$), RMSE ($48.88{\pm}1.61$), was calculated as MAE ($25.56{\pm}2.2$). SNR is also applied to examine the half-scans are not many differences in the quality of the two scan methods were not statistically significant in the scan (p-value > .05) image takes less time than a full scan was used.

U.S. Rules on Enhancing Airline Passenger Protections (미국 연방법규상 항공여객보호제도에 관한 연구)

  • Lee, Chang-Jae
    • The Korean Journal of Air & Space Law and Policy
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    • v.28 no.2
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    • pp.63-96
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    • 2013
  • Recently, U.S. Department of Transportation (DOT) expanded the "Enhancing Airline Passenger Protections" on August 23, 2011 and October 24, 2011. The Rule regulates tarmac delays, denied boarding compensation, customer service plans, and fare advertising. The adopted rule is to protect passengers by improving passenger service requirements on U.S. national or domestic carriers and foreign air carriers as well. The major issues are as follows: First, regarding to so called Tarmac Delay, carriers must establish a Tarmac Delay Contingency Plan setting forth the number of hours the carrier will permit an aircraft to remain on the tarmac at U.S. airports before allowing passengers to deplane. Carriers also must provide passengers with food and water in the event the aircraft remains on the tarmac for two or more hours and must provide operable lavatories and medical attention while the aircraft remains on the tarmac, irrespective of the length of the delay. Carriers also must create and retain records regarding tarmac delays lasting more than three hours. Also they need to update passengers every 30 minutes during a tarmac delay of the status of the flight and the reason for the delay, allow passengers to deplane if the aircraft is at the gate or another disembarkation area with the door open. Second, carriers now must adopt a "Customer Service Plan" that addresses offering customers the lowest fares available, notifying customers about delays, cancellations, and diversions; timely delivery of baggage; accommodating passengers' needs during tarmac delays and in "bumping cases"; and ensuring quality customer service. Third, the new regulations also increase minimum denied boarding compensation limits to $650 / $1,300 or 200% / 400% of the fare, whichever is less. Last, the DOT also has modified its policies related to enforcement of Rules pertaining to full fare advertising. The Rule states that the advertised price for air transportation must be the entire price to be paid by the customer. Similarly, Korea revised the passenger protection clauses within Aviation Act. However, it seems to be required to include various more issues such as Tarmac Delay, oversales of air tickets, involuntary denied boarding passengers, advertisements, etc.

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Effects of Optical Characteristics on the Growth of Benthic Microalga, Nitzschia sp. and Its Growth Kinetics of Phosphate for Bioremediation (생물적 환경정화를 위한 부착미세조류 Nitzschia sp.의 생장에 미치는 광학적 특성과 그에 따른 인산염 성장 동력학)

  • Oh, Seok-Jin;Kang, In-Seok;Yoon, Yang-Ho;Yang, Han-Soeb;Park, Jong-Sick
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.14 no.4
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    • pp.205-212
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    • 2009
  • To suggest possible to bioremediation by benthic microalgae Nitzschia sp. isolated from the Jinhae Bay, the studies investigated the effects o flight quality and quantity on the growth of Nitzschia sp. and its growth kinetics for phosphate investigated. The Nitzschia sp. was cultured under blue (450 nm), yellow (590 nm) and red wavelength (650 nm) using light emitting diode (LED) and mixed wavelengths using a fluorescent lamp. The maximum specific growth rate showed the Nitzschia sp. under blue wavelength, although photoinhibition was observed above $100\;{\mu}mol\;m^{-2}\;s^{-1}$. Mixed wavelengths were also observed by decreasing the maximum cell density from high irradiances (>$100\;{\mu}mol$ photons $m^{-2}\;s^{-1}$). The compensation photon flux density ($I_0$) calculated from the mixed wavelengths equated to a depth of 4-10 m in Jinhae Bay, and was lower in the summer season than the depth due to suspended matter (ca. 4 m). Thus, the suitable depth for maximum growth of Nitzschia sp. might be extremely limited. In the growth kinetics for phosphate, half-saturation constant ($K_s$) was similar among different wavelengths, although the maximum growth rate was varied among different wavelengths. Because the $K_s$ was high than that of the phytoplankton, Nitzschia sp. might have adapted to the high nutrient concentrations, and have effective nutrient storage in the cell quota. Thus, Nitzschia sp. may be a useful species for bioremediation of the benthic layer in polluted inner bays by means of irradiated specific wavelength as blue.