• Title/Summary/Keyword: Thickness

Search Result 24,900, Processing Time 0.177 seconds

Diagnosis of Thickness Quality Using Multivariate Statistical Analysis in Hot Finishing Mill

  • Kim, Heung-Mook
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2001.10a
    • /
    • pp.116.3-116
    • /
    • 2001
  • A diagnosis methodology for thickness quality in hot finishing mill is proposed based on multivariate statistical analysis. The thickness of hot strip is a key quality factor that is measured by x-ray thickness gauge. Currently, the thickness quality is guaranteed by upper and lower limit of thickness deviation from target thickness. But if any over-limit is occurred, there is no in-line method to identify the causes. In this paper, many parameters are extracted from the thickness deviation signal such as mean deviation(top, middle, tail), rms deviation(top, middle, tail) and peak deviation(top, middle, tail) as time domain parameters ...

  • PDF

A study on the Conversion Loss by the Thickness of the Bonding Medium in the Elastic Delay Lines. (탄성파지연선에서 접착제의 두께에 의한 변환손실에 관하여)

  • 김종상;이전영
    • Journal of the Korean Institute of Telematics and Electronics
    • /
    • v.13 no.6
    • /
    • pp.1-6
    • /
    • 1976
  • In this paper, the methode of calculating conversion loss is proposed by considering the thickness of bonding medium between electrode and delay material in the vibrator of Elastic delay lines. As the result of computations using digital computer, it is shown that the thickness of bonding medium must be less than about 1/100 of the thickness of vibrator and when the thickness of electrode is about 1110 of vibrator, the center fnequency is shifted. When the thickness of bonding medium is equal to or more than the thickness of vibrator, the 리uctuations in frequency Bandwidth become larger and larger.

  • PDF

Color soft contact lens and corneal thickness

  • Kim, Douk-Hoon
    • Journal of Korean Clinical Health Science
    • /
    • v.7 no.1
    • /
    • pp.1205-1214
    • /
    • 2019
  • Purpose: To investigate the effect of color soft contact lenses on the corneal thickness in young Korean population. Methods: The subjects consisted of 112 eyes (7 males, 49 females) with the mean age of $20.987{\pm}1.093years$ (range 20-25 years) in young Korean population during 2018. Test was compared the corneal thickness before and after wearing color soft contact lenses. The thinnest cornea thickness(TCT), central cornea thickness(CCT), pupil centre thickness(PCT), superior corneal thickness(SCT),inferior corneal thickness(ICT), medial corneal thickness(MCT), lateral corneal thickness(LCT) of the cornea was measured using the Pentacam pachymetry. The statistically analysis was perform the Shaparo-Wilk test. Results: The right eye was a statistically significant among the CCT,LCT, MCT and TCT values(p<0.001) in the compared the corneal thickness before and after wearing soft colour contact lenses. Also the left eye was a statistically significant among the LCT and MCT values(p<0.001) in the compared the corneal thickness before and after wearing soft colour contact lenses. However, there was no statistical difference (p>0.5) in the mean PCT between before and after wearing color soft contact lenses. Conclusion: These results suggested that the color soft contact lens wear can the effect the regional thickness of cornea. Therefore, the analysis of corneal topography with Pentacam can provide correct and useful diagnostic information of the morphology of the RGP contact lens fitting and diagnosis of corneal refraction surgery.

Study on Thin Sea Ice Thickness using Passive Microwave Brightness Temperature

  • Naoki, Kazuhiro;Ukita, Jinro;Nishio, Fumihiko
    • Proceedings of the KSRS Conference
    • /
    • v.2
    • /
    • pp.1015-1018
    • /
    • 2006
  • The use of passive microwave data for estimating sea-ice thickness is limited by strong dependence of emissivity on near-surface brine. However, this particular characteristic becomes a basis for an algorithm to estimate thickness of thin sea-ice if a thickness-salinity-emissivity relationship is established. This study aims at developing an algorithm to estimate sea ice thickness on the basis of this relationship. In order to establish a thickness-salinity-emissivity relationship, we have conducted multi-platform synchronous observations in the Sea of Okhotsk. We note a positive relationship between thickness and brightness temperature. From observations, we also establish an empirical relationship between salinity and emissivity, thus between thickness and brightness temperature. The derived relationship is qualitatively similar to the one based on Hoekstra and Cappillino's formulation. Our results suggest that for thin sea-ice in the winter period there is potential to develop an algorithm to estimate sea-ice thickness.

  • PDF

Studies on Thickness of Eggshell and Eggshell Membrane of Korean Native Chicken (한국 재래닭의 난각 및 난각막의 두께에 관한 연구)

  • 하정기;박준규;이정규
    • Korean Journal of Poultry Science
    • /
    • v.24 no.1
    • /
    • pp.29-37
    • /
    • 1997
  • An experiment was conducted for 20 days( from July 21 to August 10, 1996) to investigate the differences in thickness of eggshell and eggshell membrane in Korean native chicken. All the eggs were purchased from a farm located in Chinju area. All eggs were categorized into Treatment I (34.89~51.39 g), H (53.32~60.70 g), and III (34.89~60.70 g) according to their weights. Eleven items were measured in all three treatments, i.e., egg weight, egg length, egg width, breaking strength, eggshell thickness of large end(STLE), eggshell membrane thickness of large end(SMTL), eggshell thickness of small end (STSE), eggshell membrane thickness of small end(SMTS), eggshell thickness of middle part(STMP), and eggshell membrane thickness of middle part(SMTM). Correlation coefficients between egg weight and eggshell weight, among eggshell thickness of large end, small end and middle end and eggshell weight were significant (P<0.01). Correlation coefficients between egg weight and large eggshell membrane were nega-tively significant(P<0.01). Breaking strengths were higher in Treatment I than in Treatment H. Correlation coefficients among thickness of eggshell and eggshell membrane at each point at 3 parts of large end, small end and middle end were not significant.

  • PDF

A study on the thickness change according to the necking ratio of aluminum tube(A3003, A6061) (알루미늄 튜브(A3003, A6061)의 축관률에 따른 두께 변화에 관한 연구)

  • Oh, Jong-Seong;Min, Kyung-Ho;Lee, Chun-Kyu
    • Design & Manufacturing
    • /
    • v.15 no.4
    • /
    • pp.37-42
    • /
    • 2021
  • The tube necking process increases the thickness of the material, and some of the tube necking products require cutting on the inside of the formed product as a post-process. In order to prevent over-cutting or un-cutting due to increased thickness during cutting, it is necessary to know in advance the increase in thickness after forming. Therefore, in this study, the thickness change according to the tube necking was observed. Aluminum 3003-F and 6061-O were used for the materials used in the experiment, and necking was carried out up to 50% of the outer diameter of the tube through five processes. The two materials were formed under the same conditions, and the thickness of three points was observed in each process. In addition, the thickness increase of the two materials was compared, and the trend of thickness increase according to the cumulative necking ratio was observed. As a result of the experiment, both materials had the smallest thickness at the end of the formed product. In addition, as a result of comparing the thickness measurement values of the two materials, the maximum difference was 0.1mm, indicating that there was no difference in thickness between the two materials.

  • PDF

An Experimental Study on the Properties of Porous Concrete according to Correction Factor and Specimen Thickness (보정계수 및 시험체두께가 포러스콘크리트의 기초물성에 미치는 영향에 관한 실험적 연구)

  • 김재환;이성일;장종호;오시덕;박정호;김무한
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2002.11a
    • /
    • pp.55-58
    • /
    • 2002
  • This study is to analyze the influence of correction factor and specimen thickness on the fundamental properties of porous concrete. Results of this study were shown as follows; 1) As correction factor decrease, compaction time according to correction factor and specimen thickness decrease. Also, though correction factor is same, as specimen thickness increase, compaction time increase. So It mutt be considered that the influence of compaction time according to correction factor and specimen thickness. 2) As correction factor decrease, difference of measured thickness and designed thickness according to correction factor and specimen thickness decrease. Also, correction factor of aggregate of 10~l5mm is smaller than that of 5~l0mm. So It must be considered that the influence of correction factor according to size of aggregate.

  • PDF

The Influence of Engine Operating Conditions and Lubricants on Oil Film Thickness of Engine Connecting Rod Bearing (커넥팅로드 베어링의 유막두께에 미치는 기관 운전조건 및 윤활유의 영향)

  • Lee, D.H.;Chang, B.J.
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.2 no.5
    • /
    • pp.1-10
    • /
    • 1994
  • By applying of total electric capacitance method on engine connecting rod bearing during engine operating, the influence of engine operating conditions and lubricants on bearing oil film thickness was investigated. Minimum oil film thickness increases with kinematic viscosity, but as increasing of viscosity, the increasing ratio of film thickness is reduced. Also minimum oil film thickness increases with engine speed but there is a limit. Above this limit, film thickness decreases in opposition because of crankshaft inertia. As increasing of engine torque and oil temperature, munimum oil film thickness decreases linearly. For non-Newtonian oils, the correlation between $100{\circ}C$ kinematic viscosity and munimum oil film thickness is very poor.

  • PDF

A Study of the Characteristics of Thickness Distribution of Liquid Sheet Formed by Two Low Speed Impinging Jets (저속 충돌 제트로 생성되는 액막의 두께 분포 특성 연구)

  • Han, M.J.;Jeon, Y.U.;Seo, T.W.;Kang, B.S.
    • Journal of ILASS-Korea
    • /
    • v.26 no.1
    • /
    • pp.26-32
    • /
    • 2021
  • In this study, the thickness of the liquid sheet formed by two low speed impinging jets was measured by the direct contact method. The effects of jet velocity and liquid viscosity on the thickness were analyzed and the results were compared with theoretical modeling and optical thickness measurement results. The liquid film thickness decreased as the radius and circumferential angle increased. The jet velocity did not affect the liquid film thickness as predicted in theoretical modeling. In the theoretical modeling, there was no influence of the fluid properties on thickness, but in the case of low viscosity liquids, the thickness was predicted high, and it was well matched in high viscosity liquids. The direct measurement results showed no significant difference from the optical measurement results, thus confirming the reliability of the optical measurement method.

A study on magnetic layer thickness effects on magnetic properties of CoCrPt/Ti perpendicular media.

  • M. S. Hwang;Lee, T. D.
    • Proceedings of the Korean Magnestics Society Conference
    • /
    • 2000.09a
    • /
    • pp.369-376
    • /
    • 2000
  • Change of magnetic properties in CoCrPt/Ti perpendicular media with varying CoCrPt films thickness has been studied. As CoCrPt films thickness increase, the Ms(magnetization saturation) drastically increases at thinner thickness and gradually increases with further increase in thickness from 25nm. This Ms behaviour is associated with primarily the formation of "amorphous-like" reacted layer by intermixing of CoCrPt and Ti at CoCrPt/Ti interface and secondarily change of Cr segregation mode with varying the CoCrPt films thickness. Magnetic domain structure distinctively changes with increasing CoCrPt magnetic layer(ML) thickness. Also the strength of exchange coupling measured from the slope in demagnetizing region in M-H loop changes with ML thickness. Details of the above magnetic properties will be discussed. The expansion of lattice parameters a and c at thinner thickness suggests that Cr segregation mode may be connected with the residual stress of the films. Finally, negative nucleation field(Hn) behaviour with the exchange slope will be reported.

  • PDF