• Title/Summary/Keyword: Point processes

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STRONG CONVERGENCE THEOREM OF FIXED POINT FOR RELATIVELY ASYMPTOTICALLY NONEXPANSIVE MAPPINGS

  • Qin, Xiaolong;Kang, Shin Min;Cho, Sun Young
    • Journal of the Chungcheong Mathematical Society
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    • v.21 no.3
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    • pp.327-337
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    • 2008
  • In this paper, we prove strong convergence theorems of Halpern iteration for relatively asymptotically nonexpansive mappings in the framework of Banach spaces. Our results extend and improve the recent ones announced by [C. Martinez-Yanes, H. K. Xu, Strong convergence of the CQ method for fixed point iteration processes, Nonlinear Anal. 64 (2006), 2400-2411], [X. Qin, Y. Su, Strong convergence theorem for relatively nonexpansive mappings in a Banach space, Nonlinear Anal. 67 (2007), 1958-1965] and many others.

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Direct-Detection, Analysis of the point-detector arrays used in optical communication (직접검파, 광통신에 이용되는 Point-detector Array의 해석)

  • 성평식;김영권
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.12 no.5
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    • pp.428-438
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    • 1987
  • This paper describesl the point-detector arrays system to processes the field of signal and noise of the turbulent atmosphere or variance and covariance circuit. By using the aboves, the maximum output of direct-detection shows a little differences between experimental datas. As a whole the experimental data datas are agreed with the joint Gaussian theoretical curves.

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Solubility of Ibuprofen in Supercritical Carbon Dioxide (초임계 이산화탄소를 이용한 Ibuprofen의 용해도 측정)

  • Kim, Young Ae;Chu, Junho;Lim, Jong Sung;Kim, Hwayoung;Lee, Youn-Woo
    • Clean Technology
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    • v.11 no.3
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    • pp.147-152
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    • 2005
  • For estblishing the best technique for the micronization of Ibuprofen using supercritical fluids, the solubility should be known. The solubility of Ibuprofen in supercritical carbon dioxide was measured by observing the cloud point. The cloud point was observed using high pressure equipment equipped a variable volume view cell between temperature of 35, 40 and $45^{\circ}C$. The solubility data was correlated by the Peng-Robinson equation of state Solute physical properties, such as critical temperature (Tc), critical pressure (Pc) and acentric factor (${\omega}$) were estimated by the some group contribution method. As pressure was increased, the solubility increased at constant temperature. The retrograde phenomenon by a solute vapor pressure and a density of solvent was observed at the pressure of around 150bar. It was found that $CO_2$ can be used as a supercritical solvent in micronization of ibuprofen by RESS.

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Effective Point Dataset Removal for High-Speed 3D Scanning Processes (고속 3D 스캐닝 프로세스를 위한 효과적인 점데이터 제거)

  • Lim, Sukhyun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.26 no.11
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    • pp.1660-1665
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    • 2022
  • Recently, many industries are using three dimensional scanning technology. As the performance of the 3D scanner gradually improves, a sampling step to reduce a point data or a remove step to remove a part determined to be noise are generally performed in post processing. However, total point data by long time scanning cannot be processed at once in spite of performing such those additional processes. In general, a method using a multi threaded environment is widely used, but as the scanning process work time increases, the processing performance gradually decreases due to various environmental conditions and accumulated operations. This paper proposes a method to initially remove point data judged to be unnecessary by calculating accumulated fast point feature histogram values from coming point data of the 3D scanner in real time. The entire 3D scanning process can be reduced using this approach.

Process operation improvement methodology based on statistical data analysis (통계적 분석기법을 이용한 공정 운전 향상의 방법)

  • Hwang, Dae-Hee;Ahn, Tae-Jin;Han, Chonghun
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.1516-1519
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    • 1997
  • With disseminationof Distributed Control Systems(DCS), the huge amounts of process operation data could have been available and led to figure out process behaviors better on the statistical basis. Until now, the statistical modeling technology has been susally applied to process monitoring and fault diagnosis. however, it has been also thought that these process information, extracted from statistical analysis, might serve a great opportunity for process operation improvements and process improvements. This paper proposed a general methodolgy for process operation improvements including data analysis, backing up the result of analysis based on the methodology, and the mapping physical physical phenomena to the Principal Components(PC) which is the most distinguished feature in the methodology form traditional statistical analyses. The application of the proposed methodology to the Balst Furnace(BF) process has been presented for details. The BF process is one of the complicated processes, due to the highly nonlinear and correlated behaviors, and so the analysis for the process based on the mathematical modeling has been very difficult. So the statisitical analysis has come forward as a alternative way for the useful analysis. Using the proposed methodology, we could interpret the complicated process, the BF, better than any other mathematical methods and find the direction for process operation improvement. The direction of process operationimprovement, in the BF case, is to increase the fludization and the permeability, while decreasing the effect of tapping operation. These guide directions, with those physical meanings, could save fuel cost and process operator's pressure for proper actions, the better set point changes, in addition to the assistance with the better knowledge of the process. Open to set point change, the BF has a variety of steady state modes. In usual almost chemical processes are under the same situation with the BF in the point of multimode steady states. The proposed methodology focused on the application to the multimode steady state process such as the BF, consequently can be applied to any chemical processes set point changing whether operator intervened or not.

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Automatically Bending Process control for Shaft Straightening Machine (축교정기를 위한 자동굽힘공정제어기 설계)

  • 김승철
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1998.10a
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    • pp.54-59
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    • 1998
  • In order to minimize straightness error of deflected shafts, a automatically bending process control system is designed, fabricated, and studied. The multi-step straightening process and the three-point bending process are developed for the geometric adaptive straightness control. Load-deflection relationship, on-line identification of variations of material properties, on-line springback prediction, and studied for the three-point bending processes. Selection of a loading point supporting condition are derved form fuzzy inference and fuzzy self-learning method in the multi-step straighternign process. Automatic straightening machine is fabricated by using the develped ideas. Validity of the proposed system si verified through experiments.

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Adaptive Reconstruction of Harmonic Time Series Using Point-Jacobian Iteration MAP Estimation and Dynamic Compositing: Simulation Study

  • Lee, Sang-Hoon
    • Korean Journal of Remote Sensing
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    • v.24 no.1
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    • pp.79-89
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    • 2008
  • Irregular temporal sampling is a common feature of geophysical and biological time series in remote sensing. This study proposes an on-line system for reconstructing observation image series contaminated by noises resulted from mechanical problems or sensing environmental condition. There is also a high likelihood that during the data acquisition periods the target site corresponding to any given pixel may be covered by fog or cloud, thereby resulting in bad or missing observation. The surface parameters associated with the land are usually dependent on the climate, and many physical processes that are displayed in the image sensed from the land then exhibit temporal variation with seasonal periodicity. A feedback system proposed in this study reconstructs a sequence of images remotely sensed from the land surface having the physical processes with seasonal periodicity. The harmonic model is used to track seasonal variation through time, and a Gibbs random field (GRF) is used to represent the spatial dependency of digital image processes. The experimental results of this simulation study show the potentiality of the proposed system to reconstruct the image series observed by imperfect sensing technology from the environment which are frequently influenced by bad weather. This study provides fundamental information on the elements of the proposed system for right usage in application.

Rapid Manufacturing of Microscale Thin-walled Structures by Phase Change Workholding Method (상변화 고정방식에 의한 마이크로 박벽 구조물의 쾌속제작)

  • Shin, Bo-Sung
    • Journal of the Korean Society for Precision Engineering
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    • v.22 no.9 s.174
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    • pp.188-193
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    • 2005
  • To provide the various machining materials with excellent quality and dimensional accuracy, high -speed machining is very useful tool as one of the most effective rapid manufacturing processes. However, high-speed machining is not suitable for microscale thin-walled structures because of the lack of the structure stiffness to resist the cutting force. A new method which is able to make a very thin-walled structure rapidly will be proposed in this paper. This method is composed two processes, high-speed machining and filling process. Strong workholding force comes out of the solidification of filling materials. Low-melting point metal alloys are used in order to minimize the thermal effect during phase change and to hold arbitrary shape thin-walled structures quickly during high-speed machining. To verify the usefulness of this method, we will show some applications, for examples thin -wall cylinders and hemispherical shells, and compare the experimental results to analyze the dimensional accuracy of typical parts of the structures.

A Study on the Formability of Engine Cradle applied to Hydroforming according to Material Properties (하이드로포밍을 적용한 Engine Cradle의 소재 특성에 따른 성형성 고찰)

  • 박재헌;최이천;김경기
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2003.05a
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    • pp.249-253
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    • 2003
  • In recent years, developments of light weight vehicle are one of the most important issues in automotive makers. New materials and new processes have been studied on the point of weight saving of chassis worldwide. Associated with materials, applications of high strength steel, aluminium, magnesium are being developed. On the point of new processes, tailored welded blank and hydroforming have been applied. In this paper, focusing to both material and process, we have applied hydroforming process to the engine cradle. In addition to that, three kinds of high strength steel have been applied to the development of light weight material for hydroforming. All the studies have been carried by FEM.

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Research Trends of Collaborative Business Processes (협업 비즈니스 프로세스의 연구 동향)

  • 김선호;이석조
    • The Journal of Society for e-Business Studies
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    • v.8 no.1
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    • pp.15-33
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    • 2003
  • A business process is classified into two processes; the private process which is implemented within an enterprise and the public process which is implemented between enterprises. The public process commonly used for B2B e-business is defined as a collaborative business process. To date, the collaborative business process has been studied in various aspects. We have categorized the research trends into two viewpoints, i.e., EAI(Enterprise Application Integration) and B2Bi (business to business Integration). In this paper, research trends in inter-organizational workflow are analyzed from the EAI point of view, and research trends in message-based business process and transactions from the B2Bi point of view.

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