• Title/Summary/Keyword: residual time

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A Selection Method of Residual Errors for GMS Geometric Correction Using Ground Control Points

  • Yasukawa, Masaki;Takagi, Mikio;Yasuoka, Yoshifumi
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1168-1170
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    • 2003
  • The GMS geometric correction method with highspeed and high accuracy is needed. In this paper, a selection method of residual errors for the GMS geometric correction using GCPs (ground control points) is described. Namely, it is a technique for limiting the number of residual error acquisition using GCPs in each block to reduce the processing time. As the result, since the processing time was about 7.0 minutes on conventional geometric correction and about 5.6 minutes on the proposed method, it was shown that the processing time of about 1.4 minutes was shortened.

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Residual capacity assessment of in-service concrete box-girder bridges considering traffic growth and structural deterioration

  • Yuanyuan Liu;Junyong Zhou;Jianxu Su;Junping Zhang
    • Structural Engineering and Mechanics
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    • v.85 no.4
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    • pp.531-543
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    • 2023
  • The existing concrete bridges are time-varying working systems, where the maintenance strategy should be planned according to the time-varying performance of the bridge. This work proposes a time-dependent residual capacity assessment procedure, which considers the non-stationary bridge load effects under growing traffic and non-stationary structural deterioration owing to material degradations. Lifetime bridge load effects under traffic growth are predicated by the non-stationary peaks-over-threshold (POT) method using time-dependent generalized Pareto distribution (GPD) models. The non-stationary structural resistance owing to material degradation is modeled by incorporating the Gamma deterioration process and field inspection data. A three-span continuous box-girder bridge is illustrated as an example to demonstrate the application of the proposed procedure, and the time-varying reliability indexes of the bridge girder are calculated. The accuracy of the proposed non-stationary POT method is verified through numerical examples, where the shape parameter of the time-varying GPD model is constant but the threshold and scale parameters are polynomial functions increasing with time. The case study illustrates that the residual flexural capacities show a degradation trend from a slow decrease to an accelerated decrease under traffic growth and material degradation. The reliability index for the mid-span cross-section reduces from 4.91 to 4.55 after being in service for 100 years, and the value is from 4.96 to 4.75 for the mid-support cross-section. The studied bridge shows no safety risk under traffic growth and structural deterioration owing to its high design safety reserve. However, applying the proposed numerical approach to analyze the degradation of residual bearing capacity for bridge structures with low safety reserves is of great significance for management and maintenance.

Residual Voltage Properties of EPR Cables and Sheets (EPR케이블과 시트의 잔류전압 특성)

  • Lee, Sung-Ill;Bae, Duck-Kweon;Kim, Min-Ho;Song, Kee-Tae;Lee, Won-Jae;Oh, Yong-Chul;Joo, In-Kyu
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.291-292
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    • 2008
  • This study used EPR's sheet and cable as a specimen, and measured residual voltage depending on the induced voltage, thickness of the sheet, and shape of the sheet and cable. The results of the study lead to the following conclusion: 1) The residual voltage increased in proportion to the induced voltage as time increases; 2) The residual voltage of the basic mixed specimen and practical mixed specimen increased as time increased; 3) The peak of the cable appeared earlier than that of the sheet in both of the basic mixed specimen and practical mixed specimen.

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Prediction Models of Residual Chlorine in Sediment Basin to Control Pre-chlorination in Water Treatment Plant (정수장 전염소 공정 제어를 위한 침전지 잔류 염소 농도 예측모델 개발)

  • Lee, Kyung-Hyuk;Kim, Ju-Hwan;Lim, Jae-Lim;Chae, Seon Ha
    • Journal of Korean Society of Water and Wastewater
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    • v.21 no.5
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    • pp.601-607
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    • 2007
  • In order to maintain constant residual chlorine in sedimentation basin, It is necessary to develop real time prediction model of residual chlorine considering water treatment plant data such as water qualities, weather, and plant operation conditions. Based on the operation data acquired from K water treatment plant, prediction models of residual chlorine in sediment basin were accomplished. The input parameters applied in the models were water temperature, turbidity, pH, conductivity, flow rate, alkalinity and pre-chlorination dosage. The multiple regression models were established with linear and non-linear model with 5,448 data set. The corelation coefficient (R) for the linear and non-linear model were 0.39 and 0.374, respectively. It shows low correlation coefficient, that is, these multiple regression models can not represent the residual chlorine with the input parameters which varies independently with time changes related to weather condition. Artificial neural network models are applied with three different conditions. Input parameters are consisted of water quality data observed in water treatment process based on the structure of auto-regressive model type, considering a time lag. The artificial neural network models have better ability to predict residual chlorine at sediment basin than conventional linear and nonlinear multi-regression models. The determination coefficients of each model in verification process were shown as 0.742, 0.754, and 0.869, respectively. Consequently, comparing the results of each model, neural network can simulate the residual chlorine in sedimentation basin better than mathematical regression models in terms of prediction performance. This results are expected to contribute into automation control of water treatment processes.

The effect of mainshock-aftershock on the residual displacement of buildings equipped with cylindrical frictional damper

  • Mirtaheri, Masoud;Amini, Mehrshad;Rad, Moosa Doosti
    • Earthquakes and Structures
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    • v.12 no.5
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    • pp.515-527
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    • 2017
  • Recently, Friction dampers become popular due to the desirable performance in the energy dissipation of lateral loads. A lot of research which has been conducted on these dampers results in developing friction dampers with low sensitivity to the number of cycles and temperature increases. Friction dampers impose high residual drifts to the buildings because of low post-yield stiffness of the damper which results from increasing lateral displacement and period of buildings. This issue can be more critical under strong aftershocks which results in increasing of structural damages. In this paper, in addition to the assessment of aftershock on steel buildings equipped with friction dampers, methods for controlling residual drifts and decreasing the costs of retrofitting are investigated. Utilizing rigid connections as a lateral dual system and activating lateral stiffness of gravity columns by adding elastic braces are as an example of effective methods investigated in this research. The results of nonlinear time history analyses on the low to medium rise steel frames equipped with friction dampers illustrate a rise in residual drifts as the result of aftershocks. In addition, the results show that different slip loads of friction damper can affect the residual drifts. Furthermore, elastic stories in comparison to rigid connections can reduce residual drifts of buildings in an effective fashion, when most slip loads of friction dampers are considered.

A Study on Residual Stress Characteristics for Joint of Soft Rock in Ring Shear Tests (링 전단시험기를 이용한 연암의 절리에 대한 잔류강도 특성에 관한 연구)

  • 권준욱;김선명;윤지선
    • Proceedings of the Korean Geotechical Society Conference
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    • 2000.03b
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    • pp.281-288
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    • 2000
  • In this study, we tried to determine failure criteria for joints of soft rock using ring shear test machine. The residual stress fellowing shear behavior was determined by the result of ring shear test and direct shear test. Ring shear test with the specimens which cover a large deformation range was adapted to measure a residual stress, and was possible to present the peak stress to present the peak stress to the residual stress at the same time. Residual stress is defined a minimal stress of specimens with a large displacement and the result of the peak residual stress is shown by a size of displacement volume. Therefore, the residual stress in soil was decided by shear stress of maximum shear stress - shear displacement(angle) based on the test result of a hyperbolic function ((equation omitted), a, b = experimental constant). In this study, it was proved that the residual stress of rock joint can be determined by using of this method.

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Quantitative Detection of Residual E. coli Host Cell DNA by Real-Time PCR

  • Lee, Dong-Hyuck;Bae, Jung-Eun;Lee, Jung-Hee;Shin, Jeong-Sup;Kim, In-Seop
    • Journal of Microbiology and Biotechnology
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    • v.20 no.10
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    • pp.1463-1470
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    • 2010
  • E. coli has long been widely used as a host system for the manufacture of recombinant proteins intended for human therapeutic use. When considering the impurities to be eliminated during the downstream process, residual host cell DNA is a major safety concern. The presence of residual E. coli host cell DNA in the final products is typically determined using a conventional slot blot hybridization assay or total DNA Threshold assay. However, both the former and latter methods are time consuming, expensive, and relatively insensitive. This study thus attempted to develop a more sensitive real-time PCR assay for the specific detection of residual E. coli DNA. This novel method was then compared with the slot blot hybridization assay and total DNA Threshold assay in order to determine its effectiveness and overall capabilities. The novel approach involved the selection of a specific primer pair for amplification of the E. coli 16S rRNA gene in an effort to improve sensitivity, whereas the E. coli host cell DNA quantification took place through the use of SYBR Green I. The detection limit of the real-time PCR assay, under these optimized conditions, was calculated to be 0.042 pg genomic DNA, which was much higher than those of both the slot blot hybridization assay and total DNA Threshold assay, where the detection limits were 2.42 and 3.73 pg genomic DNA, respectively. Hence, the real-time PCR assay can be said to be more reproducible, more accurate, and more precise than either the slot blot hybridization assay or total DNA Threshold assay. The real-time PCR assay may thus be a promising new tool for the quantitative detection and clearance validation of residual E. coli host cell DNA during the manufacturingprocess for recombinant therapeutics.

Changes of Tap Water from the Preparation of Green Tea Leaves (녹차엽 주입에 따른 수돗물의 수질 변화)

  • Kim Chang Mo;Park Hyeon;Chang Hyun Seong;Kim Hyun Suk
    • Journal of Environmental Health Sciences
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    • v.32 no.1 s.88
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    • pp.53-59
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    • 2006
  • This study was carried out to investigate the physicochemical characteristics with the elapsed time of $1\~10$ minutes after adding green tea leaves in the tap water. The results are summarized as follows: 1. $UV_{254}$ measurement increased sharply in direct opposition to increasing conductivity slowly. It is expected that the water soluble organic matters were better extracted than minerals. 2. Residual chlorine decay coefficients evaluated by assuming first-order reaction was increased in proportion to adding weights of green tea leaves. 3. In DBP formation experiments, residual chlorine decreased when reaction time was elapsed. whereas DBPs such as HAAs and THMs increased with the passing of time. From these results, it was showed that residual chlorine decay was related with the formation of DBPs. Therefore, use of boiled tap water in preparation of green tea is suggested if the residual chlorine in the tap water is high.

Numerical Analysis of Residual Stresses and Birefringence in Injection/Compression Molded Center-gated Disks (II) - Effects of Processing Conditions - (사출/압축 성형 Center-gated 터스크에서의 잔류 응력과 복굴절의 수치 해석 (II) - 공정조건의 영향 -)

  • Lee, Young-Bok;Kwon, Tai-Hun;Yoon, Kyung-Hwan
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.26 no.11
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    • pp.2355-2363
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    • 2002
  • The accompanying paper, Part 1, has presented the physical modeling and basic numerical analysis results of both the flow-induced and thermally-induced residual stress and birefringence in injection molded center gated disks. The present paper, Part II, has attempted to investigate the effects of various processing conditions of injection/compression molding process on the residual stress and birefringence. The birefringence is significantly affected by injection melt temperature, packing pressure and packing time. Birefringence in the shell layer increases as melt temperature gets lower. The inner peak of birefringence increases with packing time and packing pressure. On the other hand, packing pressure, packing time and mold wall temperature affect the thermally-induced residual stress rather significantly in the shell layer, but insignificantly in the core region. Injection/compression molding has been found to reduce the birefringence in comparison with the conventional injection molding process. In particular, mold closing velocity and initial opening thickness in the compression stage of injection/compression molding process have significant effect on the flow-induced birefringence, but not on tile thermal residual stress and the thermally induced birefringence.

Study on Bladder Dysfunction in Elderly Women by the BFLUT Questionnaire and Bladder Scanner: Frequency and Residual Urine (질문지법과 초음파 방광용적진단기를 이용한 여성노인의 배뇨장애연구 -빈뇨, 잔뇨를 중심으로)

  • Kim, Jeung-Im
    • Women's Health Nursing
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    • v.17 no.3
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    • pp.294-303
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    • 2011
  • Purpose: This study aimed to describe bladder dysfunction in elderly women such as frequency, nocturia, and residual urine. Methods: One hundred elderly women aged 60 and over. The Bristol Female Lower Urinary Symptoms (BFLUT) was used to evaluate the bladder function and to measure the residual urine amount by using a bladder scanner. Data was analyzed with the differences between voiding dysfunction by age group and life habits by t-test, ANOVA and correlation by Pearson correlation coefficient. Results: the mean daytime frequency was 6.8 times and night-time frequency 2.7 times. Sixty three percent of subjects had urgency and 41% had urgent incontinence. Over half of subjects had problem in voiding function. There were significant differences in frequency by age groups and constipation, but not in daytime frequency and residual urine. Lastly, there were significant positive relations between daytime frequency and night-time frequency. Also results indicate that more frequency in daytime equaled to a less residual urine amount. Conclusion: We know many elderly women have lower urinary tract symptoms. Specially women over 75 years have more daytime frequency and night-time frequency. This suggests further research needed in order to understand the relation of voiding patterns and life habits and its influence on quality of life.