• Title/Summary/Keyword: observational method

Search Result 317, Processing Time 0.026 seconds

Newly Developed Settlement Prediction Method on Soft Soils with Subsequent Surcharge Change (성토고 변화를 고려한 새로운 연약 지반 침하 예측 기법)

  • Chun, Sung-Ho;Kim, Han-Saem;Yune, Chan-Young;Chung, Choong-Ki
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.31 no.5C
    • /
    • pp.155-162
    • /
    • 2011
  • Settlement prediction based on field monitored data, which is used to control subsequent surcharges, is very important in construction management for soft ground improvement with the preloading method. Observational settlement prediction methods, which are suggested for an instantaneous loading, have been widely used in fields. However, they have difficulties in the settlement prediction with subsequent surcharge change. In this paper, a simple method to predict the settlement with subsequent surcharge change is suggested. The suggested method adopts assumptions to simplify the complex field condition and utilizes observational methods. The suggested method is applied to a large consolidation test result, FDM analysis results, and field monitored settlement data to confirm its practicability. From the applications, the suggested method produces reasonable prediction results with various subsequent surcharge changes.

Total Management System for Earth Retaining Structures Using Observational Method (지반굴착 흙막이공의 정보화시공 종합관리 시스템)

  • 오정환;조철현;김기웅;백영식
    • Journal of the Korean Geotechnical Society
    • /
    • v.18 no.2
    • /
    • pp.51-64
    • /
    • 2002
  • Observational results of ground movement during the construction were very different from those predicted during the analysis of design step because of the uncertainty of the numerical analysis modelling, the soil parameter, and the condition of a construction field, etc., however accurately numerical analysis method was applied for prediction of ground movement per the excavation step. Therefore, the management system through the construction field measurement should be achieved for grasping the situation during the excavation. Until now, the measurement system restricted by 'Absolute Value Management system'analyzing only the stability of present step has been executed. So, it was difficult to expect the prediction of ground movement fur the next excavation step. In this situation, this study developed 'The Management system TOMAS-EXCAV'consisted of 'Absolute value management system'analyzing the stability of present step and 'Prediction management system'expecting the ground movement of next excavation step and analyzing the stability of next excavation step by 'Back Analysis'. TOMAS-EXCAV could be applied to all the uncertainty of earth retaining structures analysis by connecting 'Forward analysis program'and 'Back analysis program'and optimizing the main design variables using SQP-MMFD optimization method through measurement results. The applicability of TOMAS-EXCAV was confirmed by back analysis selecting two earth retains construction fields.

Project Risk Management & Observational Method for soft ground improvement (연약지반을 대상으로 한 프로젝트 리스크와 현장계측의 과제와 대책)

  • Imanishi, Hajime
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2006.10a
    • /
    • pp.509-514
    • /
    • 2006
  • Considering the risk management, there are many examples and various studies for the corporation risk. However, I have never seen the project risk management that applied a construction site for practical approach. Therefore, I have developed a chart (I-Chart) for the project risk management, and also built a model (I-Chart scenario analysis) that I could use. I applied this model to container yard reclaimed land in harbor construction with approaching of geotechnical engineering.

  • PDF

Spin and shape analysis for the Mars-crossing asteroid 2078 Nanking

  • Choi, Jung-Yong;Kim, Myung-Jin;Choi, Young-Jun;Yoon, Tae Seog
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.40 no.1
    • /
    • pp.85.2-86
    • /
    • 2015
  • The YORP effect is non-gravitational force that changes the spin-status of asteroid. So far this effect has been directly detected only from the Near-Earth asteroids (Taylor et al. 2007; Lowry et al. 2007, 2014; Breiter et al. 2011; Durech et al. 2008, 2012). Pravec at el. 2008 found the evidences for changing spin rate of small asteroids (3 - 15 km) by the YORP effect in the Main-Belt and Mars-crossing asteroids. The Mars-crossing asteroids (1.3 < q < 1.66 AU) are objects that cross orbit of the Mars. The Mars-crossing asteroids are regarded as one of the main sources for the Near-Earth asteroids. We expect that rotation of Mars-crossing asteroids would be influenced by the YORP effect. We try to search observational evidence of the YORP effect for the Mars-crossing asteroid. Our target 2078 Nanking is a population of the Mars-crossing asteroid. First light-curve of 2078 Nanking was obtained from Mohamed et al. 1994, and Warner et al. 2015 recently published new observational data. We observed this asteroid on 26th Nov. 2014 and 17th Jan. 2015 using SOAO (Sobaeksan Optical Astronomy Observatory) 0.61 m telescope with 4K CCD. Using light-curve inversion method (Kaasalainen & Torppa 2001; Kaasalainen et al. 2001), we try to determine the pole orientation and shape model of this asteroid based on the combination of our light-curve and literature photometric data. Knowing spin parameters, such as rotational period and spin axis, are essential for studying the YORP effect. In this presentation, we provide some preliminary results of our recent study: light-curve and processing of shape modeling of 2078 Nanking. We plan to find observational clue for the YORP effect on the Mars-crossing asteroids.

  • PDF

A Systematic Review on Pain Assessment Tools for Intensive Care Unit Patients (중환자 통증 평가 도구에 관한 체계적 문헌고찰)

  • Kim, Eun-Jeong;Hong, Jiwon;Kang, Jiyeon;Kim, Na geong;Kim, NaRi;Maeng, Su-Youn;Park, Hye-Ryeon;Ban, Min Kyung;Yang, Gun Young;Lee, Kyung Suk;Jang, Eun Hye
    • Journal of Korean Critical Care Nursing
    • /
    • v.13 no.1
    • /
    • pp.44-62
    • /
    • 2020
  • Purpose : The purpose of this study was to systematically review the measurement tools that are used to assess the pain of intensive care unit (ICU) patients. Method : In this systematic review, the studies published between 2009 and 2018 were selected based on the PRISMA flow chart. Data sources included MEDLINE, EMBASE, CINAHL, and Cochran. We assessed the quality of pain assessment tools reported in individual studies using Terwee et al.'s the Quality Criteria for Measurement Properties. Results : We reviewed 67 studies and 12 pain assessment tools that included two self-reported, seven observational, and three multifaced tools with observations and physiological indicators. The most frequently used tool was the Critical Care Pain Observation Tool. The Multidimensional Observational Pain Assessment Tool was rated the highest quality. Nine of the ten tools that included observations reported content validity, four reported construct validity and nine reported correlation coefficient. Conclusion : It was found that observational tools are appropriate for assessing pain in ICU patients with limited communication skills. To increase the validity and reliability of pain assessment in ICU patients, further research on the physiological indicators of pain is needed.

Application of a Statistical Interpolation Method to Correct Extreme Values in High-Resolution Gridded Climate Variables (고해상도 격자 기후자료 내 이상 기후변수 수정을 위한 통계적 보간법 적용)

  • Jeong, Yeo min;Eum, Hyung-Il
    • Journal of Climate Change Research
    • /
    • v.6 no.4
    • /
    • pp.331-344
    • /
    • 2015
  • A long-term gridded historical data at 3 km spatial resolution has been generated for practical regional applications such as hydrologic modelling. However, overly high or low values have been found at some grid points where complex topography or sparse observational network exist. In this study, the Inverse Distance Weighting (IDW) method was applied to properly smooth the overly predicted values of Improved GIS-based Regression Model (IGISRM), called the IDW-IGISRM grid data, at the same resolution for daily precipitation, maximum temperature and minimum temperature from 2001 to 2010 over South Korea. We tested various effective distances in the IDW method to detect an optimal distance that provides the highest performance. IDW-IGISRM was compared with IGISRM to evaluate the effectiveness of IDW-IGISRM with regard to spatial patterns, and quantitative performance metrics over 243 AWS observational points and four selected stations showing the largest biases. Regarding the spatial pattern, IDW-IGISRM reduced irrational overly predicted values, i. e. producing smoother spatial maps that IGISRM for all variables. In addition, all quantitative performance metrics were improved by IDW-IGISRM; correlation coefficient (CC), Index Of Agreement (IOA) increase up to 11.2% and 2.0%, respectively. Mean Absolute Error (MAE) and Root Mean Square Error (RMSE) were also reduced up to 5.4% and 15.2% respectively. At the selected four stations, this study demonstrated that the improvement was more considerable. These results indicate that IDW-IGISRM can improve the predictive performance of IGISRM, consequently providing more reliable high-resolution gridded data for assessment, adaptation, and vulnerability studies of climate change impacts.

Improving CMD Areal Density Analysis: Algorithms and Strategies

  • Wilson, R.E.
    • Journal of Astronomy and Space Sciences
    • /
    • v.31 no.2
    • /
    • pp.121-130
    • /
    • 2014
  • Essential ideas, successes, and difficulties of Areal Density Analysis (ADA) for color-magnitude diagrams (CMD's) of resolved stellar populations are examined, with explanation of various algorithms and strategies for optimal performance. A CMD-generation program computes theoretical datasets with simulated observational error and a solution program inverts the problem by the method of Differential Corrections (DC) so as to compute parameter values from observed magnitudes and colors, with standard error estimates and correlation coefficients. ADA promises not only impersonal results, but also significant saving of labor, especially where a given dataset is analyzed with several evolution models. Observational errors and multiple star systems, along with various single star characteristics and phenomena, are modeled directly via the Functional Statistics Algorithm (FSA). Unlike Monte Carlo, FSA is not dependent on a random number generator. Discussions include difficulties and overall requirements, such as need for fast evolutionary computation and realization of goals within machine memory limits. Degradation of results due to influence of pixelization on derivatives, Initial Mass Function (IMF) quantization, IMF steepness, low Areal Densities ($\mathcal{A}$), and large variation in $\mathcal{A}$ are reduced or eliminated through a variety of schemes that are explained sufficiently for general application. The Levenberg-Marquardt and MMS algorithms for improvement of solution convergence are contained within the DC program. An example of convergence, which typically is very good, is shown in tabular form. A number of theoretical and practical solution issues are discussed, as are prospects for further development.

Design of a Neuro Observer for Reduction of Estimate Error (추정오차 저감을 위한 뉴로 관측기 설계)

  • Nam Moon-Hyon;Yoon Kwang-Ho
    • The Transactions of the Korean Institute of Electrical Engineers D
    • /
    • v.54 no.5
    • /
    • pp.285-290
    • /
    • 2005
  • The state observer is being used widely because it has the advantage of the guarantee of reliability on financial problem, over heating, and physical shock. However, an Luenberger observer and a Sliding observer have such problems that an experimenter needs to know dynamics and parameters of the system. And also, the high gain observer has such a problem that it has transient state at the beginning of the observation. In this paper, the Neuro observer is proposed to improve these problems. The proposed Neuro observer complement a problem that occur from increase of gain of High-gain observer in proportion to the square number of observable state variables. And also, the proposed Neuro observer can tune the gain obtained by differentiating observational error at transient state automatically by using the backpropagation training method to stabilize the observational speed. To prove a performance of the proposed observer, it is simulated that the comparison between the state estimate performance of the proposed observer and that of Sliding, High gain observer is made by using a sinusoidal input to the observer which consists of four layers in stable 2nd order system.

The Marital Interaction Coding System-Global(MICS-G): A Validation Study (포괄적 부부상호작용 코딩시스템(MICS-G) 국내 타당화 연구)

  • Park, Woochul
    • Human Ecology Research
    • /
    • v.57 no.1
    • /
    • pp.109-125
    • /
    • 2019
  • Few studies have utilized observational methods in the field of couple research even though using self-report questionnaires is prone to the subjective biases of the reporter. This study validates the Marital Interaction Coding System-Global (MICS-G), a global version of the well-established microanalytic observational coding system, Marital Interaction Coding System (MICS). Participants in the study consisted of 30 married couples with varied levels of marital adjustment who visited one of the Healthy Family and Multicultural Family Support Centers in Seoul, either for couple therapy or the "Marriage Checkup"program. Ten-minute problem-solving discussions were rated by two undergraduate student raters who were trained for 10 hours. Interobserver agreement based on percentage agreement and intraclass correlation coefficients showed a high level of agreement between raters in establishing interrater reliability. Convergent validity was established by: correlations among marital adjustment, psychological aggression, mental health, and MICS-G categories of conflicts, validation, invalidation, facilitation, and withdrawal. MICS-G categories also were successful in discriminating between distressed and nondistressed couples, which provides evidence of discriminant validity for MICS-G. This study showed that MICS-G is a promising method for researchers to observe couple interactions in a more cost-effective way. Methodological issues and practical applications are also discussed.

Study on Development of HDD Integrity Verification System using FirmOS (FirmOS를 이용한 HDD 무결성 검사 시스템 개발에 관한 연구)

  • Yeom, Jae-Hwan;Oh, Se-Jin;Roh, Duk-Gyoo;Jung, Dong-Kyu;Hwang, Ju-Yeon;Oh, Chungsik;Kim, Hyo-Ryoung;Shin, Jae-Sik
    • Journal of the Institute of Convergence Signal Processing
    • /
    • v.18 no.2
    • /
    • pp.55-61
    • /
    • 2017
  • In radio astronomy, high-capacity HDDs are being used to save huge amounts of HDDs in order to record the observational data. For VLBI observations, observational speeds increase and huge amounts of observational data must be stored as they expand to broadband. As the HDD is frequently used, the number of failures occurred, and then it takes a lot of time to recover it. In addition, if a failed HDD is continuously used, observational data loss occurs. And it costs a lot of money to buy a new HDD. In this study, we developed the integrity verification system of the Serial ATA HDD using FirmOS. The FirmOS is an OS that has been developed to function exclusively for specific purposes on a system having a general server board and CPU. The developed system performs the process of writing and reading specific patterns of data in a physical area of the SATA HDD based on a FirmOS. In addition, we introduced a method to investigate the integrity of HDD integrity by comparing it with the stored pattern data from the HDD controller. Using the developed system, it was easy to determine whether the disk pack used in VLBI observations has error or not, and it is very useful to improve the observation efficiency. This paper introduces the detail for the design, configuration, testing, etc. of the SATA HDD integrity verification system developed.

  • PDF