• Title/Summary/Keyword: in situ monitoring

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Integrated Water Resources Management in the Era of nGreat Transition

  • Ashkan Noori;Seyed Hossein Mohajeri;Milad Niroumand Jadidi;Amir Samadi
    • Proceedings of the Korea Water Resources Association Conference
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    • 2023.05a
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    • pp.34-34
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    • 2023
  • The Chah-Nimeh reservoirs, which are a sort of natural lakes located in the border of Iran and Afghanistan, are the main drinking and agricultural water resources of Sistan arid region. Considering the occurrence of intense seasonal wind, locally known as levar wind, this study aims to explore the possibility to provide a TSM (Total Suspended Matter) monitoring model of Chah-Nimeh reservoirs using multi-temporal satellite images and in-situ wind speed data. The results show that a strong correlation between TSM concentration and wind speed are present. The developed empirical model indicated high performance in retrieving spatiotemporal distribution of the TSM concentration with R2=0.98 and RMSE=0.92g/m3. Following this observation, we also consider a machine learning-based model to predicts the average TSM using only wind speed. We connect our in-situ wind speed data to the TSM data generated from the inversion of multi-temporal satellite imagery to train a neural network based mode l(Wind2TSM-Net). Examining Wind2TSM-Net model indicates this model can retrieve the TSM accurately utilizing only wind speed (R2=0.88 and RMSE=1.97g/m3). Moreover, this results of this study show tha the TSM concentration can be estimated using only in situ wind speed data independent of the satellite images. Specifically, such model can supply a temporally persistent means of monitoring TSM that is not limited by the temporal resolution of imagery or the cloud cover problem in the optical remote sensing.

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On-line Monitoring of IPTG Induction for Recombinant Protein Production Using an Automatic pH Control Signal

  • Hur Won;Chung Yoon-Keun
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.10 no.4
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    • pp.304-308
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    • 2005
  • The response of IPTG induction was investigated through the monitoring of the alkali consumption rate and buffer capacity during the cultivation of recombinant E. coli BL21 (DE3) harboring the plasmid pRSET-LacZ under the control of lac promoter. The rate of alkali consumption increased along with cell growth, but declined suddenly after approximately 0.2 h of IPTG induction. The buffer capacity also declined after 0.9 h of IPTG induction. The profile of buffer capacity seems to correlate with the level of acetate production. The IPTG response was monitored only when introduced into the mid-exponential phase of bacterial cell growth. The minimum concentration of IPTG for induction, which was found out to be 0.1 mM, can also be monitored on-line and in-situ. Therefore, the on-line monitoring of alkali consumption rate and buffer capacity can be an indicator of the metabolic shift initiated by IPTG supplement, as well as for the physiological state of cell growth.

Satellite monitoring of land and vegetation and its potential application in urban sustainability

  • Feng, Xue-zhi;Ramadan, Elnazir
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.78-81
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    • 2003
  • The present study illustrates a method for monitoring the urban vegetation around Shaoxing city, Monitoring spatiotemporal changes in urban areas will become increasingly important as the number and proportion of urban residents continues to increase. The synoptic view of urban land cover provided by satellite and airborne sensors is an important complement to in situ measurements of physical, environmental and socioeconomic variables in urban settings. The results obtained have revealed a notable change in the vegetation cover in and around the City premises. In this study, we discussed methodology for measurement of urban vegetation and vegetation distributions based on band ratioing in Shaoxing city using Land sat TM imageries. A systematic analysis of the spatiotemporal dynamics of vegetation in urban areas is required to ensure a healthy sustainable environment.

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Geochemical and S isotopic studies of pollutant evolution in groundwater after acid in situ leaching in a uranium mine area in Xinjiang

  • Zhenzhong Liu;Kaixuan Tan;Chunguang Li;Yongmei Li;Chong Zhang;Jing Song;Longcheng Liu
    • Nuclear Engineering and Technology
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    • v.55 no.4
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    • pp.1476-1484
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    • 2023
  • Laboratory experiments and point monitoring of reservoir sediments have proven that stable sulfate reduction (SSR) can lower the concentrations of toxic metals and sulfate in acidic groundwater for a long time. Here, we hypothesize that SSR occurred during in situ leaching after uranium mining, which can impact the fate of acid groundwater in an entire region. To test this, we applied a sulfur isotope fractionation method to analyze the mechanism for natural attenuation of contaminated groundwater produced by acid in situ leaching of uranium (Xinjiang, China). The results showed that δ34S increased over time after the cessation of uranium mining, and natural attenuation caused considerable, area-scale immobilization of sulfur corresponding to retention levels of 5.3%-48.3% while simultaneously decreasing the concentration of uranium. Isotopic evidence for SSR in the area, together with evidence for changes of pollutant concentrations, suggest that area-scale SSR is most likely also important at other acid mining sites for uranium, where retention of acid groundwater may be strengthened through natural attenuation. To recapitulate, the sulfur isotope fractionation method constitutes a relatively accurate tool for quantification of spatiotemporal trends for groundwater during migration and transformation resulting from acid in situ leaching of uranium in northern China.

Multi-sensor data fusion based assessment on shield tunnel safety

  • Huang, Hongwei;Xie, Xin;Zhang, Dongming;Liu, Zhongqiang;Lacasse, Suzanne
    • Smart Structures and Systems
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    • v.24 no.6
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    • pp.693-707
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    • 2019
  • This paper proposes an integrated safety assessment method that can take multiple sources data into consideration based on a data fusion approach. Data cleaning using the Kalman filter method (KF) was conducted first for monitoring data from each sensor. The inclination data from the four tilt sensors of the same monitoring section have been associated to synchronize in time. Secondly, the finite element method (FEM) model was established to physically correlate the external forces with various structural responses of the shield tunnel, including the measured inclination. Response surface method (RSM) was adopted to express the relationship between external forces and the structural responses. Then, the external forces were updated based on the in situ monitoring data from tilt sensors using the extended Kalman filter method (EKF). Finally, mechanics parameters of the tunnel lining were estimated based on the updated data to make an integrated safety assessment. An application example of the proposed method was presented for an urban tunnel during a nearby deep excavation with multiple source monitoring plans. The change of tunnel convergence, bolt stress and segment internal forces can also be calculated based on the real time deformation monitoring of the shield tunnel. The proposed method was verified by predicting the data using the other three sensors in the same section. The correlation among different monitoring data has been discussed before the conclusion was drawn.

Estimation of Coastal Suspended Sediment Concentration using Satellite Data and Oceanic In-Situ Measurements

  • Lee, Min-Sun;Park, Kyung-Ae;Chung, Jong-Yul;Ahn, Yu-Hwan;Moon, Jeong-Eun
    • Korean Journal of Remote Sensing
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    • v.27 no.6
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    • pp.677-692
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    • 2011
  • Suspended sediment is an important oceanic variable for monitoring changes in coastal environment related to physical and biogeochemical processes. In order to estimate suspended sediment concentration (SSC) from satellite data, we derived SSC coefficients by fitting satellite remote sensing reflectances to in-situ suspended sediment measurements. To collect in-situ suspended sediment, we conducted ship cruises at 16 different locations three times for the periods of Sep.-November 2009 and Jul. 2010 at the passing time of Landsat $ETM_+$. Satellite data and in-situ data measured by spectroradiometers were converted to remote sensing reflectances ($R_{rs}$). Statistical approaches proved that the exponential formula using a single band of $R_{rs}$(565) was the most appropriate equation for the estimation of SSC in this study. Satellite suspended sediment using the newly-derived coefficients showed a good agreement with insitu suspended sediment with an Root Mean Square (RMS) error of 1-3 g/$m^3$. Satellite-observed SSCs tended to be overestimated at shallow depths due to bottom reflection presumably. This implies that the satellite-based SSCs should be carefully understood at the shallow coastal regions. Nevertheless, the satellite-derived SSCs based on the derived SSC coefficients, for the most cases, reasonably coincided with the pattern of in-situ suspended sediment measurements in the study region.

In-Situ Application of the Steel Pipe jacking with Grouting (그라우팅을 병행한 강관추진공법의 현장 적용성 연구)

  • Jung, Min-Hyung;Lim, Ho-Jung;Shin, Chang-Sub;Lee, Song
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.13 no.1 s.53
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    • pp.152-160
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    • 2009
  • The pipe jacking method which is a non-excavation method is frequently used due to constructability and economical efficiency in a medium or small-sized pipeline construction. However, jacking process of the method still causes problems that the base ground is disturbed and loosen. These lead to surface settlement, strength decrease and leakage of water. Therefore, this study presents in-situ application of the steel pipe jacking with grouting, and it is that jacking and grouting are progressed simultaneously. To verify this, the steel pipe jacking with grouting and the existing steel pipe jacking have been constructed on the same ground condition. It has been proved that the steel pipe jacking with grouting is in-situ applicable according to results of monitoring surface settlement, in-situ density, GPR geophysical prospecting and large scale direct shear test.

An experimental procedure for evaluating the consolidation state of marine clay deposits using shear wave velocity

  • Chang, Ilhan;Kwon, Tae-Hyuk;Cho, Gye-Chun
    • Smart Structures and Systems
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    • v.7 no.4
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    • pp.289-302
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    • 2011
  • In marine clay deposits, naturally formed or artificially reclaimed, the evaluation and monitoring of the consolidation process has been a critical issue in civil engineering practices due to the time frame required for completing the consolidation process, which range from several days to several years. While complementing the conventional iconographic method suggested by Casagrande and recently developed in-situ techniques that measure the shear wave, this study suggests an alternative experimental procedure that can be used to evaluate the consolidation state of marine clay deposits using the shear wave velocity. A laboratory consolidation testing apparatus was implemented with bimorph-type piezoelectric bender elements to determine the effective stress-shear wave velocity (${\sigma}^{\prime}-V_s$) relationship with the marine clays of interest. The in-situ consolidation state was then evaluated by comparing the in-situ shear wave velocity data with the effective stress-shear wave velocity relationships obtained from laboratory experiments. The suggested methodology was applied and verified at three different sites in South Korea, i.e., a foreshore site in Incheon, a submarine deposit in Busan, and an estuary delta deposit in Busan. It is found that the shear wave-based experimental procedure presented in this paper can be effectively and reliably used to evaluate the consolidation state of marine clay deposits.

Case history in prediction of consolidation settlement and monitoring (준설매립 초연약지반의 압밀침하 거동 및 계측 사례)

  • Jeon, Je-Sung;Lee, Jong-Wook;Im, Eun-Sang;Kim, Jae-Hong
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.10a
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    • pp.1712-1716
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    • 2008
  • Performance of ground improvement project using prefabricated vertical drains of condition, in which approximately 10m dredged fill overlies original soft foundation layer in the coastal area has been conducted. From field monitoring results, excessive ground settlement compared to predicted settlement in design stage developed during the following one year. In order to predict the final consolidation behavior, recalculation of consolidation settlements and back analysis using observed settlements were conducted. Field monitoring results of surface settlements were evaluated, and then corrected because large shear deformation was occurred by construction events in the early stages of consolidation. To predict the consolidation behavior, material functions and in-situ conditions from laboratory consolidation test were re-analyzed. Using these results, height of additional embankment is estimated to satisfy residual settlement limit and maintain an adequate ground elevation. The recalculated time-settlement curve has been compared to field monitoring results after additional surcharge was applied.

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Airborne Fine Particle Measurement Data Analysis and Statistical Significance Analysis (공기중 미세입자 측정 데이터 분석 및 통계 유의차 분석)

  • Sung Jun An;Moon Suk Hwan
    • Journal of the Semiconductor & Display Technology
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    • v.22 no.1
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    • pp.1-5
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    • 2023
  • Most of the production process is performed in a cleanroom in the case of facilities that produce semiconductor chips or display panels. Therefore, environmental management of cleanrooms is very important for product yield and quality control. Among them, airborne particles are a representative management item enough to be the standard for the actual cleanroom rating, and it is a part of the Fab or Facility monitoring system, and the sequential particle monitoring system is mainly used. However, this method has a problem in that measurement efficiency decreases as the length of the sampling tube increases. In addition, a statistically significant test of deterioration in efficiency has rarely been performed. Therefore, in this study, the statistically significant test between the number of particles measured by InSitu and the number of particles measured for each sampling tube ends(Remote). Through this, the efficiency degradation problem of the sequential particle monitoring system was confirmed by a statistical method.

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