• Title/Summary/Keyword: accuracy-study

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A Study on the Development of Dredge Process Management System (준설공정관리시스템 개발에 관한 연구)

  • 정대득;이중우;조증언
    • Journal of Korean Port Research
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    • v.15 no.1
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    • pp.75-85
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    • 2001
  • Accuracy of dredging processes depends on the types of equipment used, the sediments encountered, whether the work to be performed is new or maintenance dredging, pre- and post-hydrographic surveying and so forth. Among those, position surveying accuracy which is directly determined by the control of the dredge's position and depth surveying accuracy being surveyed at the dredging point during dredging work are important factors. The purpose of this study is to develop 'Dredge Management System'for Grab dredge which is composed of 4 sub-system using LADGPS for dredge position determining system and dredging point determining system, tide gauge system and optical sensor for depth determining system and GIS and ENC for total management system. This system is installed on the grab dredge 'EUNJIN G-18'and applied to anchorage dredging work. at Pohang Harbor. The results revealed that this system is easy to operate, achieves good accuracy with only 45cm unevenness, reduces working period by 22 percent and saves cost 16.6 percent.

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A Verification of the Accuracy in BIM-Based Quantity Taking-Off - Focusing on Finishing Work (BIM 기반 물량 산출의 정확성 검증 - 마감공사 공종을 중심으로)

  • Kim, Ji-Hyun;Yoon, Su-Won
    • Journal of KIBIM
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    • v.3 no.2
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    • pp.1-9
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    • 2013
  • Currently, various studies and applications related BIM based quantity take-off have been attempted, because of the accuracy of cost estimating and reliability by using the BIM model information in automatical calculation. Finishing works that have a large number of various types and materials need the higher accuracy and reliability on the BIM-based quantity take-off. Therefore, this study compared and analyzed 2D and 3D based quantity through Test-bed and determine the cause of the quantity difference. This verified the accuracy and efficiency in the BIM-based quantity take-off for finishing works. Also this study has been proposed opinions for calculating the exact BIM-based quantity take-off.

A Study on the Accuracy of Convergent Photographs Using Non-Metric Camera (비측량용 사진기에 의한 수렴사진의 정확도에 관한 연구)

  • Yeu, Bock-Mo;Kwon, Hyon;Yu, Ki-Yun
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.7 no.2
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    • pp.63-68
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    • 1989
  • This study was to develope the methmatic prediction model of accuracy for the convergent photographs using nonmetric camera in close range photogrammetry. By analyzing positioning error on object distance and convergent angles, the validity of the new formulae for prediction of accuracy were proved. Rational design of camera systems and convergent angles according to accuracy demands in plane and height were developed using these formulae.

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Improvement of flood simulation accuracy based on the combination of hydraulic model and error correction model

  • Li, Li;Jun, Kyung Soo
    • Proceedings of the Korea Water Resources Association Conference
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    • 2018.05a
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    • pp.258-258
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    • 2018
  • In this study, a hydraulic flow model and an error correction model are combined to improve the flood simulation accuracy. First, the hydraulic flow model is calibrated by optimizing the Manning's roughness coefficient that considers spatial and temporal variability. Then, an error correction model were used to correct the systematic errors of the calibrated hydraulic model. The error correction model is developed using Artificial Neural Networks (ANNs) that can estimate the systematic simulation errors of the hydraulic model by considering some state variables as inputs. The input variables are selected using parital mutual information (PMI) technique. It was found that the calibrated hydraulic model can simulate flood water levels with good accuracy. Then, the accuracy of estimated flood levels is improved further by using the error correction model. The method proposed in this study can be used to the flood control and water resources management as it can provide accurate water level eatimation.

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Rhythmic Initiation in the respect of Information Processing approach (정보처리접근에서의 율동적 개시)

  • Choi, Jae-Won;Chung, Hyun-Ae
    • PNF and Movement
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    • v.9 no.1
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    • pp.55-63
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    • 2011
  • Purpose : This study was to investigate the application of Rhythmic Initiation(RI) in the respect of information processing in motor learning. Methods : A computer-aided literature search was performed in PubMed and adapted to the other databases and the others were in published books. The following keywords were used: Rhythmic Initiation, attention, memory, motor accuracy, feedback, motor learning, motor control, PNF, cognition. Results : The characterization of RI is rhythmic motion of limb or body through the desired range, starting with passive motion and progressing to active resisted movement. This study suggested that the relationship between of RI and motor learning through the respect of information processing, memory, attention and motor accuracy. Conclusion : Only Rhythmic Initiation, specifically focused on the effects of information processing approach, suggesting that RI can be positively influeced on sensory-perception, attention, memory, motor accuracy. however, it is unclear whether positive effects in the laboratory and field can be generalized to improve. In addition, sustainability of motor learning with RI remains uncertain.

DG-based SPO tuple recognition using self-attention M-Bi-LSTM

  • Jung, Joon-young
    • ETRI Journal
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    • v.44 no.3
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    • pp.438-449
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    • 2022
  • This study proposes a dependency grammar-based self-attention multilayered bidirectional long short-term memory (DG-M-Bi-LSTM) model for subject-predicate-object (SPO) tuple recognition from natural language (NL) sentences. To add recent knowledge to the knowledge base autonomously, it is essential to extract knowledge from numerous NL data. Therefore, this study proposes a high-accuracy SPO tuple recognition model that requires a small amount of learning data to extract knowledge from NL sentences. The accuracy of SPO tuple recognition using DG-M-Bi-LSTM is compared with that using NL-based self-attention multilayered bidirectional LSTM, DG-based bidirectional encoder representations from transformers (BERT), and NL-based BERT to evaluate its effectiveness. The DG-M-Bi-LSTM model achieves the best results in terms of recognition accuracy for extracting SPO tuples from NL sentences even if it has fewer deep neural network (DNN) parameters than BERT. In particular, its accuracy is better than that of BERT when the learning data are limited. Additionally, its pretrained DNN parameters can be applied to other domains because it learns the structural relations in NL sentences.

Using Standard Deviation with Analogy-Based Estimation for Improved Software Effort Prediction

  • Mohammad Ayub Latif;Muhammad Khalid Khan;Umema Hani
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.5
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    • pp.1356-1376
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    • 2023
  • Software effort estimation is one of the most difficult tasks in software development whereas predictability is also of equal importance for strategic management. Accurate prediction of the actual cost that will be incurred in software development can be very beneficial for the strategic management. This study discusses the latest trends in software estimation focusing on analogy-based techniques to show how they have improved the accuracy for software effort estimation. It applies the standard deviation technique to the expected value of analogy-based estimates to improve accuracy. In more than 60 percent cases the applied technique of this study helped in improving the accuracy of software estimation by reducing the Magnitude of Relative Error (MRE). The technique is simple and it calculates the expected value of cost or time and then uses different confidence levels which help in making more accurate commitments to the customers.

A study on the surface accuracy according to applied load in burnishing of steel

  • Lee, Y.C.;Yuck, K.S.
    • Journal of the Korean Society for Precision Engineering
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    • v.10 no.1
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    • pp.70-76
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    • 1993
  • Burnishing, as a micro plastic working, is a finishing process used in conjuction with or in replacement of reaming, honing, lapping, and/or grinding. The tool which is a smooth, round steel ball slightly larger than the bore is pushed through pre-machined hole, leaving a closely controlled finish. The major application of the processes is to improve the geometric and mechanical properties of surface such as (1) dimensional accuracy, (2) surface roughness, (3) bearing ratio, (4) surface hardness, (5) wear resistance, (6) fatigue and corrosion resistance, etc. Therefore, this study carried out some experiments to illustrate the theoretical formula and to investigate surface accuracy (e.g. variation of diameter, surface roughness, bearing ratio) in accordance with the applied burnishing load.

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Improvement of Robot Motion Accuracy Through Link Parameter Calibrationa (연자보정 방법을 이용한 로보트 운동 정밀도 개선)

  • 이상조;조의정
    • 제어로봇시스템학회:학술대회논문집
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    • 1988.10a
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    • pp.21-26
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    • 1988
  • The application of robot to industry is increasing and as a result the study on robot is widely being carried out. In this study, to improve the accuracy of robot motion the method which calibrates initially assumed link parameters is considered. This method calibrates 4N link parameters for N D.O.F. robot with rigid links.

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The Effect of Earnings Quality on Financial Analysts' Dividend Forecast Accuracy: Evidence from Korea

  • NAM, Hye-Jeong
    • The Journal of Asian Finance, Economics and Business
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    • v.6 no.4
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    • pp.91-98
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    • 2019
  • Dividend policy is an important business decision and is considered a channel to communicate a firm's performance to shareholders. Given the empirical findings that earnings quality significantly affects financial analysts' forecasting activities, it is predicted that higher earnings quality would positively influence forecast accuracy. Specifically, it is expected that financial analysts would forecast dividends more accurately for firms with higher earning quality. Unlike the research on financial analysts' earnings forecasts was heavily conducted, there is little study about financial analysts' dividend forecasts. This paper examines the effect of earnings quality on financial analysts' dividend forecast accuracy. We use a sample of South Korean firms for the period of 2011-2015 for multivariate regression. Earnings quality is measured by accruals quality and performance-adjusted discretionary accruals followed by prior studies. We first compare the accuracy between dividend forecasts and earnings forecasts using t-test and Wilcoxon singed-rank test. It is confirmed that financial analysts' dividend forecasts are more accurate than earnings forecasts in Korea. We find that financial analysts' dividend forecasts are more accurate for firms with higher earnings quality. We also find that the result is still valid after controlling for the accuracy of financial analysts' earnings forecasts. This confirms that earnings quality positively affects financial analysts' dividend forecasts.