• Title/Summary/Keyword: Spring band

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Numerical Analysis of the Contact Stress Behaviour in Scraper Seals (스크레이퍼 시일의 접촉응력 거동에 관한 수치적 연구)

  • 나윤환;김청균;류병진;유인석
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 1997.04a
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    • pp.198-203
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    • 1997
  • This paper deals with a numerical study of the tribological contact stress distributions of elastomeric lip seah for oscillating shafts when the sealing interference and band width between the lip edge of contact seals the shaft are present. Using the finite element method, the contact stress and band width of scraper seals rare analyzed for the sealing interference including some nonlinearities such as geometrical nonlinearity, material nonlinearity and nonlinear contact boundary condition. The FEM results showed that the contact stress concentrated on the contacting lip zone between the contacting edge of lip and the shaft for the increased interference. In double lip scraper seals, the maximum contact stress of the dust lip, which is used to exclude foreign contaminants, is six times higher than that of the primary sealing lip, which is used to contain lubricants.

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Correction of Tooth-to-tooth Contact and Class IV Mesiodistocclusion by Orthodontic Tooth Movement in Three Dogs (세 마리 개에서 교정적 치아이동에 의한 치아-치아 접촉 및 IV급 근원심교합의 교정)

  • Kim, Se-Eun;Shim, Kyung-Mi;Kang, Seong-Soo
    • Journal of Veterinary Clinics
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    • v.33 no.1
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    • pp.25-29
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    • 2016
  • Three Maltese dogs, 5 to 7 months old, were admitted to the Veterinary Medical Teaching Hospital, Chonnam National University with malocclusion including Class IV mesiodistocclusion. In the first case, the treatment was performed by moving the mandibular canine teeth caudally with orthodontic buttons and Masel chains. The second patient was treated for rostroverted mandibular canines using buttons and chains. When distal movement of the mandibular canine teeth was completed, a maxillary arch wire with finger springs was applied to push the incisor teeth forward. In the third case, the treatment began by moving the mandibular canine teeth caudally with buttons and chains. An arch wire with finger springs was applied at maxilla to move the maxillary incisor teeth labially. Additionally, the mandibular incisor teeth were moved lingually by an elastic band attached to the buttons cemented to mandibular canine teeth. As a result, all patients successfully regained a normal occlusion.

RADARSAT SAR Investigations of Lineament and Spring Water in Cheju Island (RADARSAT SAR 자료를 이용한 제주도 선구조 연구 및 용천 특성 연구)

  • 원중선;류주형;지광훈
    • Korean Journal of Remote Sensing
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    • v.14 no.4
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    • pp.325-342
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    • 1998
  • Two RADARSAT SAR images with different modes acquired by Canadian Space Agency to test the effectiveness of geological lineament extraction and spring water detection over the Cheju Island. Geological lineaments are poorly developed this basalt dominant volcanic island, but more linear features can be extracted when SAR and TM images are simultaneously analyzed than when TM image alone is used. This results mainly owe to the facts that RADARSAT SAR systems are able to provide data with different frequencies, azimuth, and incidence angles. Distribution of spring water along coast is poorly correlated with geological lineaments or drainage pattern, but those in middle range of mountain region are developed along geological lineaments. Detection of spring water using remotely sensed images are turned out to be very difficult to achieve. Radial shaped sea surface temperature anomaly derived from TM thermal band should be the best candidate for spring water, but the resolution is not high enough. We also investigate the normalized radar cross section (or sigma naught) converted from RADARSAT and ERS-1 SAR data but to discriminate the spring water effectively except where relatively large water mass is observed on land side. Speckle noise and irregularity in physical sea surface condition are the serious obstacles for this application. ERS-1 SAR image acquired in low incidence angle was more useful for geological lineament estimation and water body study than RADARSAT SAR images with high incidence angles. Therefore the selection of incidence angle is critical in geological and spring water applications of SAR images, and low incidence angles less than about 30$^{\circ}$ are recommended to monitor the Cheju volcanic island.

Application of Hyperspectral Imagery to Decision Tree Classifier for Assessment of Spring Potato (Solanum tuberosum) Damage by Salinity and Drought (초분광 영상을 이용한 의사결정 트리 기반 봄감자(Solanum tuberosum)의 염해 판별)

  • Kang, Kyeong-Suk;Ryu, Chan-Seok;Jang, Si-Hyeong;Kang, Ye-Seong;Jun, Sae-Rom;Park, Jun-Woo;Song, Hye-Young;Lee, Su Hwan
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.21 no.4
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    • pp.317-326
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    • 2019
  • Salinity which is often detected on reclaimed land is a major detrimental factor to crop growth. It would be advantageous to develop an approach for assessment of salinity and drought damages using a non-destructive method in a large landfills area. The objective of this study was to examine applicability of the decision tree classifier using imagery for classifying for spring potatoes (Solanum tuberosum) damaged by salinity or drought at vegetation growth stages. We focused on comparing the accuracies of OA (Overall accuracy) and KC (Kappa coefficient) between the simple reflectance and the band ratios minimizing the effect on the light unevenness. Spectral merging based on the commercial band width with full width at half maximum (FWHM) such as 10 nm, 25 nm, and 50 nm was also considered to invent the multispectral image sensor. In the case of the classification based on original simple reflectance with 5 nm of FWHM, the selected bands ranged from 3-13 bands with the accuracy of less than 66.7% of OA and 40.8% of KC in all FWHMs. The maximum values of OA and KC values were 78.7% and 57.7%, respectively, with 10 nm of FWHM to classify salinity and drought damages of spring potato. When the classifier was built based on the band ratios, the accuracy was more than 95% of OA and KC regardless of growth stages and FWHMs. If the multispectral image sensor is made with the six bands (the ratios of three bands) with 10 nm of FWHM, it is possible to classify the damaged spring potato by salinity or drought using the reflectance of images with 91.3% of OA and 85.0% of KC.

A Study on Fashion Design of Silver Age -Focused on Elderly Women's Clothing Design Preference : An Application of Delphi Method- (실버패션디자인 연구 - 노년여성의 의복디자인선호도를 중심으로: 델파이법의 적용 -)

  • Chang, An-Hua
    • Fashion & Textile Research Journal
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    • v.7 no.6
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    • pp.577-584
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    • 2005
  • The aims of this study are primary data offer to silver fashion enterprise. In order to deduce design from diverse needs of silver generation, this study is required expert knowledge. For this purpose, this study applied two rounded Delphi method in which 31 experts. As a result, the following findings were obtained; From the previous studies, we found the physical changes of women in silver generation; i.e. the size of their waist and abdomen gets larger, their breasts are sagging, their limbs are thinner, upper body is bending, their height and weight get shorter and lighter. Their choice criterion of design of clothing is hide their weak points in body, youthfulness, moderate, and fashion style. Youthful design but patterns should agree with their body line so that they should be easily fit and look young. They like a jacket and pants set best regardless of spring or summer and as upper garment, they like semi fit, as pants, they prefer straight line of ankle length, and as skirts, partial elastic band and pleats, and the length of the skirts just cover their knees. This pattern in choosing their clothes represents they consider functionality as well as the aesthetics. Their preferred color for spring is lt/pink, lt/violet lt/green for summer, white and blue. Their preferred materials are wool/poly/spandex and cotton/spandex for functionality for spring, and for summer, linen poly and cotton poly seersucker for cool feeling and stability. In both top and bottom item, solid pattern follows small one in their preference on patterns, which shows that they are in pursuit of an elegant style. Our research based on this survey tries to establish what the fashion design for the silver generation should take into consideration.

Purification and Characterization of Thermostable Agarase from Bacillus sp. BI-3, a Thermophilic Bacterium Isolated from Hot Spring

  • Li, Jiang;Sha, Yujie;Seswita-Zilda, Dewi;Hu, Qiushi;He, Peiqing
    • Journal of Microbiology and Biotechnology
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    • v.24 no.1
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    • pp.19-25
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    • 2014
  • An extracellular agarase was purified from Bacillus sp. BI-3, a thermophilic agar-degrading bacterium isolated from a hot spring in Indonesia. The purified agarase revealed a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, with an apparent molecular mass of 58 kDa. The optimum pH and temperature of the agarase were 6.4 and $70^{\circ}C$, respectively. The activity of the agarase was stable at high temperatures, and more than 50% activity was retained at $80^{\circ}C$ for 15 min. Furthermore, the enzyme was stable in the pH range of 5.8-8.0, and more than 60% of the residual activity was retained. Significant activation of the agarase was observed in the presence of $K^+$, $Na^+$, $Ca^{2+}$, $Mg^{2+}$, and $Sr^{2+}$; on the other hand, $Ba^{2+}$, $Zn^{2+}$, $Cu^{2+}$, $Mn^{2+}$, $Co^{2+}$, $Fe^{2+}$, and EDTA inhibited or inactivated the enzyme activity. The components of the hydrolytic product analyzed by thin-layer chromatography showed that the agarase mainly produced neoagarobiose. This study is the first to present evidence of agarolytic activity in aerobic thermophilic bacteria.

SEOUL NATIONAL UNIVERSITY CAMERA II (SNUCAM-II): THE NEW SED CAMERA FOR THE LEE SANG GAK TELESCOPE (LSGT)

  • Choi, Changsu;Im, Myungshin
    • Journal of The Korean Astronomical Society
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    • v.50 no.3
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    • pp.71-78
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    • 2017
  • We present the characteristics and the performance of the new CCD camera system, SNUCAM-II (Seoul National University CAMera system II) that was installed on the Lee Sang Gak Telescope (LSGT) at the Siding Spring Observatory in 2016. SNUCAM-II consists of a deep depletion chip covering a wide wavelength from $0.3{\mu}m$ to $1.1{\mu}m$ with high sensitivity (QE at > 80% over 0.4 to $0.9{\mu}m$). It is equipped with the SDSS ugriz filters and 13 medium band width (50 nm) filters, enabling us to study spectral energy distributions (SEDs) of diverse objects from extragalactic sources to solar system objects. On LSGT, SNUCAM-II offers $15.7{\times}15.7$ arcmin field-of-view (FOV) at a pixel scale of 0.92 arcsec and a limiting magnitude of g = 19.91 AB mag and z=18.20 AB mag at $5{\sigma}$ with 180 sec exposure time for point source detection.

Regional variations of optical properties on asteroid (25143) Itokawa taken with the Asteroid Multi-band Imaging Camera (AMICA) on-board the Hayabusa spacecraft

  • Lee, Mingyeong;Ishiguro, Masateru
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.2
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    • pp.45.1-45.1
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    • 2015
  • Hayabusa is the JAXA's space mission that succeeded in sample-return from S-type asteroid (25143) Itokawa. During the rendezvous phase, more than a thousand of images were taken with the Asteroid Multi-band Imaging Camera (AMICA). It is valuable to study the regional variation of the optical properties on the asteroid using these images to know the generality and uniqueness of the returned samples. In addition, AMICA images are important in that they provide unique data set at low phase angle (i.e Sun-Itokawa-AMICA's angle) that have not been explored in the previous asteroidal missions. At the previous conference (2015 KAS spring meeting), we introduced our preliminary data analysis of AMICA data without considering the shape model of Itokawa and mentioned. In this study, we present a new result obtained through further analysis, taking account of the shape model of the asteroid. We thus utilized "plate_renderer" tool to derive Hapke model parameters at different terrains. It is found that the opposition amplitude (parameter B0) is consistent with those of the other S-type asteroids while the opposition width (parameter h) is significantly narrower than those of the other S-type asteroids. At this conference, we plan to describe the regional variation of photometric properties on Itokawa.

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Wave energy converter by using relative heave motion between buoy and inner dynamic system

  • Cho, I.H.;Kim, M.H.;Kweon, H.M.
    • Ocean Systems Engineering
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    • v.2 no.4
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    • pp.297-314
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    • 2012
  • Power-take-off through inner dynamic system inside a floating buoy is suggested. The power take-off system is characterized by mass, stiffness, and damping and generates power through the relative heave motion between the buoy and inner mass (magnet or amateur). A systematic hydrodynamic theory is developed for the suggested WEC and the developed theory is illustrated by a case study. A vertical truncated cylinder is selected as a buoy and the optimal condition of the inner dynamic system for maximum PTO (power take off) through double resonance for the given wave condition is systematically investigated. Through the case study, it is seen that the maximum power can actually be obtained at the optimal spring and damper condition, as predicted by the developed WEC theory. However, the band-width of high performance region is not necessarily the greatest at the optimal (maximum-power-take-off) condition, so it has to be taken into consideration in the actual design of the WEC.

An Experimental Study of the Transmissibility of Vehicle Compact Disk Player (차량 탑재용 컴팩트 디스크 플레이어의 전달률에 관한 실험적 연구)

  • Lee, Tae-Keun;Kim, Byoung-Sam
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.15 no.6 s.99
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    • pp.764-771
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    • 2005
  • This study investigates the 3-axis transmissibility of the vehicle compact disk player's mainbase which is supported by dampers and springs. These dampers and springs as the important element ' determining the vibration performance of vehicle compact disk Player are used to minimize the vibration which is induced by driving the vehicle. In order to determine the analysis frequency band, we investigated the excitation frequency of road from the vehicle test. As the characteristics of damper and spring were changed, we carried out the vibration test and investigated the change of transmissibility, Also, we carried out the sensitivity analysis for transmissibility and we found out that the properties of damper were the dominant element in the vibration performance of vehicle compact disk player.