• Title/Summary/Keyword: Delta-Average

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Displacement Characteristics of Soft Ground by Embankment Construction (제방축조에 의한 연약지반의 변위특성)

  • Ahn, Kwangkuk;Bae, Wooseok
    • Journal of the Korean GEO-environmental Society
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    • v.8 no.2
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    • pp.29-39
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    • 2007
  • In this study, the centrifugal tests were fulfilled to analyze the displacement characteristics caused by the embankment construction on soft ground. Embankment of height, undrained shear strength and with or without geotextile were selected to evaluate the displacement characteristics of soft ground by embankment. As a result, the replacement section without geotextile showed the parabola shape. The replacement section with geotextile showed the trapezoidal shape which represents the uniform settlements. The replacement angle is increasing nearly lineally with increasing the height of embankment and G-level. The position, where the maximum horizontal displacement occurred, was between $0.24H_0$ and $0.35H_0$ and was at $0.3H_0$ on the average. In the case of with and without geotextile, the relationship between the maximum settlement of ground(S) and maximum horizontal displacement(${\delta}_m$) was ${\delta}_m$ = 0.60S, ${\delta}_m$ = 0.54S, respectively.

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Investigation of the horizontal heterophoria measurement at distance by various testing method (사위검사 방법의 차이에 따른 원거리 수평사위 검사값 비교)

  • Sim, Hyun-Seog;Lee, Seang-Wook;Jang, Seong-Joo
    • Journal of Korean Ophthalmic Optics Society
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    • v.6 no.2
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    • pp.155-160
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    • 2001
  • To investigate the subjective refractive error with Von Graefe test. Maddox Rod test and polarizing lens test of Horizontal Heterophoria Measurement at distance on normal 109 subjects aged from 18 to 30 years old. The results were as follows: 1. Using Von Graefe Horizontal Heterophoria Measurement, they were measured 15% for orthophoria, 65% for exophoria and 20% for esophoria at distance. 2. Using Maddox Rod Horizontal Heterophoria Measurement, they were measured 14% for orthophoria, 57% for exophoria and 29% for esophoria at distance. 3. Using polarizing lens test of Horizontal Heterophoria Measurement, they were measured 15% for orthophoria, 72% for exophoria and 13% for esophoria at distance. 4. Each test average were $1.32{\Delta}BI$ for Von Graefe test, $0.88{\Delta}BI$ for Maddox Rod test and $1.76{\Delta}BI$ for polarizing lens test. 5. Patient's preference distribution were 44% for Von Graefe test, 28% for Maddox Rod test and 28% for polarizing lens test.

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Unaided Stapling Technique for Pure Single-Incision Distal Gastrectomy in Early Gastric Cancer: Unaided Delta-Shaped Anastomosis and Uncut Roux-en-Y Anastomosis

  • Suh, Yun-Suhk;Park, Ji-Ho;Kim, Tae Han;Huh, Yeon-Ju;Son, Young Gil;Yang, Jun-Young;Kong, Seong-Ho;Lee, Hyuk-Joon;Yang, Han-Kwang
    • Journal of Gastric Cancer
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    • v.15 no.2
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    • pp.105-112
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    • 2015
  • Purpose: Intracorporeal anastomosis is the most difficult procedure during pure single-incision distal gastrectomy (SIDG) that affects its generalization. We introduced unaided delta-shaped anastomosis (uDelta), a novel anastomosis technique, for gastroduodenostomy after pure SIDG, and compared the results with those of previously reported Roux-en-Y anastomosis (RY). Materials and Methods: Between March 2014 and March 2015, SIDG with D1+ lymph node dissection was performed for early gastric cancer through a 2.5-cm transumbilical incision without any additional port. uDelta was performed by the operator alone, without any intracorporeal assistance. Results: uDelta was performed on 11 patents, and uncut RY was performed on 5-patients without open or multiport conversion. R0 resection was performed in all cases. No significant differences were observed in mean age and body mass index between patients who underwent uDelta or RY. Mean operation times were $214.5{\pm}36.2$ minutes for uDelta and $240.8{\pm}65.9$ minutes for RY, which was not significantly different. Reconstruction time for uDelta was shorter than that for RY, with marginal statistical significance ($26.1{\pm}8.3$ minutes vs. $38.0{\pm}9.1$ minutes, P=0.05). There were no intraoperative transfusions, 30-day mortality, or anastomosis-related complications in either group. Average length of hospital stay was $8.2{\pm}1.9$ days in the uDelta group and $7.2{\pm}0.8$ days in the RY group (P=0.320). Conclusions: After carefully considering indications, uDelta can be a feasible and can be a reproducible reconstruction method after SIDG in early gastric cancer.

A Study on Vertical Distribution and Origin of Particulate Organic Matter in Shingu Reservoir in Pre-monsoon and Post-monsoon Period - Application of Carbon and Nitrogen Stable Isotope Ratio - (하계 강우기 전.후 신구저수지 내 입자성유기물의 수직분포 및 기원 연구 - 탄소 및 질소 안정동위원소비의 활용 -)

  • Kim, Min-Seob;Lee, Yeon-Jung;Shin, Kyung-Hoon;Hwang, Soon-Jin
    • Korean Journal of Ecology and Environment
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    • v.41 no.spc
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    • pp.27-34
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    • 2008
  • The vertical distribution and origin of particulate organic matter (POM) were investigated in Shingu reservoir on 4th July (pre-monsoon) and 7th August (post-monsoon) 2006. High turbid water (120 NTU) were found at 4.5 m water depth in postmonsoon period. The average C/N ratio of POM was about 5.70 and 6.96 in surface water and bottom water, respectively in pre-monsoon period, exhibiting the close values to its ratio in phytoplankton cell. However, the average C/N ratio was 7.10 in surface water and 12.81 in bottom water in post-monsoon period. In addition, the ${\delta}^{13}C$ values of POM in pre-monsoon period ranged from -25.1%o to -26.1%o in whole water column, but the ${\delta}^{13}C$ values of POM in post-monsoon period showed relatively wide range between -23.2%o and -27.5%o. The apparently lighter values (average -27.5%o) in near bottom water (4.5 m water depth) demonstrate that POM in high turbid water in post-monsoon period may be derived from the outside terrestrial plants through heavy rainfall during the summer monsoon period. The present study suggests that carbon and nitrogen stable isotope ratios as well as C/N ratios should be useful indexes to clarify the origin of POM.

Evaluation of Plastic Anisotropy in the Steel Sheets Using EMAT (EMAT를 이용한 판재의 소성이방성 평가)

  • Ahn, B.Y.;Kim, Y.G.;Lee, S.S.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.17 no.4
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    • pp.270-277
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    • 1997
  • Plastic anisotropy is one of important factors which determine the drawability of a steel sheet. It has been mainly measured by mechanical tensile test. From the ultrasonic velocities propagating along the relative directions to the rolling direction, CODF(crystallite orientation distribution function) can be measured and ODC's(orientation distribution coefficients) has some correlations with the plastic anisotropy. In this study the correlations between the plastic anisotropy and ODC's of the cold rolled steel sheet were measured. From the results of ultrasonic velocity measurements the average normal anisotropy, $\bar{\gamma}$ and the average planar anisotropy, ${\Delta}r$ could be predicted within the accuracy of ${\pm}0.082$ and ${\pm}0.096$, respectively. Acoustic resonance method was applied to measure the ultrasonic velocities and EMAT's were used for generating and detecting the ultrasonic waves.

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Adaptive Partitioning for Efficient Query Support

  • Yun, Hong-Won
    • Journal of information and communication convergence engineering
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    • v.5 no.4
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    • pp.369-373
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    • 2007
  • RFID systems large volume of data, it can lead to slower queries. To achieve better query performance, we can partition into active and some nonactive data. In this paper, we propose two approaches of partitioning for efficient query support. The one is average period plus delta partition and the other is adaptive average period partition. We also present the system architecture to manage active data and non-active data and logical database schema. The data manager check the active partition and move all objects from the active store to an archive store associated with an average period plus data and an adaptive average period. Our experiments show the performance of our partitioning methods.

Molecular Structure and Gelatinization Properties of Turnip Starch (Brassica rapa L.)

  • Kim, Nam-Hee;Yoo, Sang-Ho
    • Food Science and Biotechnology
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    • v.14 no.4
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    • pp.470-473
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    • 2005
  • Starch was isolated from turnip (Brassica rapa L.), and to elucidate the structure-function relationship its structural and physical properties were characterized. Morphological structure of the starch was analyzed by SEM (Scanning Electron Microscopy). Most of the starch granules were spherical in shape with diameter ranging from 0.5-10mm. Apart from larger granules ($<10\;{\mu}m$) which dominated the population size of turnip starch, significant amount of small ($0.5-2\;{\mu}m$) and mid-size granules (${\sim}\;{\mu}m$) were also detected. It was revealed that presumably, erosion damages occurred due to the attack of amylase-type enzymes on the surface of some granules. Branch chain-length distribution was analyzed by HPAEC (High-Performance Anion-Exchange Chromatography). The chain-length distribution of turnip starch revealed a peak at DP12 with obvious shoulder at DP18-21. The weight-average chain length ($CL_{avg}$) was 16.6, and a large proportion (11.8%) of very short chains (DP6-9) was also observed. The melting properties of starch were determined by DSC (Differential Scanning Calorimetry). The onset temperature ($T_o$) and the enthalpy change (${\Delta}H$) of starch gelatinization were $50.5^{\circ}C$ and 12.5 J/g, respectively. The ${\Delta}H$ of the retrograded turnip starch was 3.5 J/g, which indicates 28.2% of recrystallization. Larger proportion of short chains as well as smaller average chain-length can very well explain relatively lower degree of retrogradation in turnip starch.

Effects of Steel Fiber, Zircon, and Cashew in the Brake Friction Materials on Creep Groan Phenomena (자동차 브레이크용 마찰재 내의 강철섬유, 지르콘, 캐슈가 크립 그론에 미치는 영향)

  • Jang, Ho;Lee, Kang-Sun;Lee, Eun-Ju;Jeong, Geun-Joong;Song, Hyun-Woo
    • Tribology and Lubricants
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    • v.23 no.6
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    • pp.278-282
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    • 2007
  • Friction characteristics of a low-steel friction material were examined to investigate creep groan phenomena. The amount of three ingredients (steel fiber, $ZrSiO_4$, cashew) were changed to produce test specimens using a constrained mixture design. Tribological properties of the friction material specimens were obtained by using a 1/5 scale dynamometer. Results showed that the amount of three different ingredients strongly affected the level of friction coefficient and the difference between the static friction coefficient and the kinetic friction coefficient $({\Delta}{\mu}).\;ZrSiO_4$ and steel fiber tended to increase the average friction coefficient and aggravated the stick-slip phenomena suggesting high creep groan propensity. On the other hand, cashew tended to decrease average friction coefficient and ${\Delta}{\mu}$.

Structural and Dielectric Properties of (Sr.Ca)$TiO_3$-based Ceramics with the Substitution of Ca (Ca 치환에 따른 (Sr.Ca)$TiO_3$계 세라믹스의 구조적 및 유전 특성)

  • 최운식;강재훈;서용진;김창일;김충혁;박용필
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.14 no.11
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    • pp.879-884
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    • 2001
  • In this paper, the structural and dielectric properties of (Sr$_{l-x}$Ca$_{x}$)TiO$_3$ (0$\leq$x$\leq$0.2) -based grain boundary layer ceramics were investigated by XRD, SEM and HP4194A. The ceramics were fabricated by the conventional mixed oxide method. The sintering temperature and time were 1420~152$0^{\circ}C$ and 4 hours, respectively. The average grain size and the lattice constant were decreased with increasing content of Ca. The average grain size was increased with increase of sintering temperature. The relative density of all specimens was 96~98%. The 2nd Phase formed by the thermal diffusion of CuO from the surface leads to very excellent dielectric properties, that is, $\varepsilon$$_{r}$>50000, tan $\delta$<0.05, $\Delta$C<$\pm$10%. The appropriate Ca content was under 15 ㏖%.s under 15 ㏖%.%.

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Separation of $H_2$/$N_2$ Gas Mixture by PTMSP-PEI and PDMS-PEI Composite Membranes (PTMSP-PEI와 PDMS-PEI 복합막에 의한 수소/질소 혼합기체 분리)

  • 강태범;조성혜;이현경
    • Membrane Journal
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    • v.13 no.4
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    • pp.291-299
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    • 2003
  • Polymer membranes such as poly(1-trimethylsilyl-1-propyne)-polyetherimide (PTMSP-PEI) and poly(dimethylsiloxane)- polyetherimide (PDMS-PEI) composite membrane were prepared by solution casting method. To investigate the characteristics of these membranes, the analytical methods such as FT-IR, $^1H-NMR,$ DSC, TGA, GPC, and SEM have been utilized. The number-average (equation omitted) and weight-average (equation omitted) molecular weight of PTMSP were 477,920 and 673,329 respectively. The glass transition temperature ($T_g$) of PTMSP was $224^{\circ}C.$ The separation of the gas mixture ($H_2/N_2$) through the composite membranes were studied as a function of pressure. The separation factor (${\alpha}, {\beta},$ quation omitted) of the composite membranes used in this work increased as the pressure of permeation cell increased. The real separation factor (${\alpha}$), head separation factor (${\beta}$), and tail separation factor (equation omitted) of PTMSP-PEI composite membrane were 2.28, 1.17, and 1.96 respectively at ${\Delta}P$ 30psi and $25^{\circ}C.$ (${\alpha}, {\beta}$ and equation omitted of PDMS-PEI composite membrane were 3.70, 1.53, and 2.42 respectively at ${\Delta}P$ 30psi and $25^{\circ}C$.