• Title/Summary/Keyword: Point processes

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Shopping Mall Business Process Modeling Using IDEF3 Part 1 - Front office view point (IDEF3를 이용한 쇼핑몰 업무 프로세스 모델링 Part 1 - Front office 관점)

  • Jeon, Tae-Bo
    • Journal of Industrial Technology
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    • v.25 no.A
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    • pp.105-113
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    • 2005
  • A business process flow model for an intermediary type shopping mall consisting of multiple sellers has been presented in this study. Specifically, we defined 11 essential business processes of a front office customer's view point and set up detailed process flow models using IDEF3 (Integrated DEFinition). The characteristic of this study lies in providing a dynamic model rather than static models. The results may form a conceptual framework not only for shopping mall processes but for analysis and improvement toward extended electronic business systems.

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Automatic Building Extraction Using LIDAR Data

  • Cho, Woo-Sug;Jwa, Yoon-Seok
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1137-1139
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    • 2003
  • This paper proposed a practical method for building detection and extraction using airborne laser scanning data. The proposed method consists mainly of two processes: low and high level processes. The major distinction from the previous approaches is that we introduce a concept of pseudogrid (or binning) into raw laser scanning data to avoid the loss of information and accuracy due to interpolation as well as to define the adjacency of neighboring laser point data and to speed up the processing time. The approach begins with pseudo-grid generation, noise removal, segmentation, grouping for building detection, linearization and simplification of building boundary , and building extraction in 3D vector format. To achieve the efficient processing, each step changes the domain of input data such as point and pseudo-grid accordingly. The experimental results shows that the proposed method is promising.

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PID Controller Tuning Rules for Integrating Processes with Time Delay (시간지연을 갖는 적분시스템용 PID 제어기의 동조규칙)

  • Lee, Yun-Hyung;So, Myung-Ok;Hwang, Seung-Wook;Ahn, Jong-Kap;Kim, Min-Jung;Jin, Gang-Gyoo
    • Journal of Advanced Marine Engineering and Technology
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    • v.30 no.6
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    • pp.753-759
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    • 2006
  • Integrating processes are frequently encountered in process industries. In this paper, new tuning formulae of the PID controllers for set-point tracking and load disturbance rejection are presented for integrating processes involving time delay. First, the controller parameter sets are tuned using a real-coded genetic algorithm (RCGA) such that performance criterion(IAE, ISE or ITSE) is minimized. Then, tuning rules are addressed using tuned PID parameter sets. tuning model and another RCGA. The performances of the proposed rules are tested on two processes.

AN ANALYSIS OF THE MEMORY RELATED COMMUNICATION SYSTEM

  • Lim, Jong-Seul;Park, Chin-Hong
    • Journal of applied mathematics & informatics
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    • v.16 no.1_2
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    • pp.539-550
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    • 2004
  • We consider communication or computer systems that have the average memory occupancy and congestion. A certain system may be reduced further if new processes are admitted only when the number of processes queued at the processor is below a certain threshold, run queue cutoff(RQ). We show that response time of a process is invariant with respect to RQ when processes do not communicate each other. The invariance property is considered with the evolution of the queue lengths as point processes and demonstrate it numerically using matrix-geometric methods. We illustrate the RQ invariance property.

PID Tuning Algorithm Using Reduction Model (축소 모델을 이용한 PID 동조 알고리즘)

  • Ryu, Young-Guk;Cho, Joon-Ho;Choi, Jung-Nae;Hwang, Hyung-Su
    • Proceedings of the KIEE Conference
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    • 2000.07d
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    • pp.2648-2650
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    • 2000
  • The PID tuning algorithm which can be applied generally to processes with varies dynamic characteristics is proposed by Wang[7]. However, it can be applied well to process model without zeros and with $\angle$G(jw)=-${\pi}$/2 and -${\pi}$ point in Nyquist curve, but it gives unsatisfactory tuning performance for processes with zeros and without $\angle$G(jW)=-${\pi}$/2 and -${\pi}$ in Nyquist curve. In this paper, the method which improve it using Pade reduction method is proposed. Satisfactory responses can be expected for processes with various dynamics, including those with low or high order, small or large dead time, monotonic or oscillatory responses. Simulation examples are given to show the effectiveness and flexibility of the controller in handling processes of different characteristics.

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A class of CUSUM tests using empirical distributions for tail changes in weakly dependent processes

  • Kim, JunHyeong;Hwang, Eunju
    • Communications for Statistical Applications and Methods
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    • v.27 no.2
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    • pp.163-175
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    • 2020
  • We consider a wide class of general weakly-dependent processes, called ψ-weak dependence, which unify almost all weak dependence structures of interest found in statistics under natural conditions on process parameters, such as mixing, association, Bernoulli shifts, and Markovian sequences. For detecting the tail behavior of the weakly dependent processes, change point tests are developed by means of cumulative sum (CUSUM) statistics with the empirical distribution functions of sample extremes. The null limiting distribution is established as a Brownian bridge. Its proof is based on the ψ-weak dependence structure and the existence of the phantom distribution function of stationary weakly-dependent processes. A Monte-Carlo study is conducted to see the performance of sizes and powers of the CUSUM tests in GARCH(1, 1) models; in addition, real data applications are given with log-returns of financial data such as the Korean stock price index.

Comparison of Energy Consumptions for Various Forming Processes (성형 가공 차이에 의한 에너지 소비량 비교)

  • Yin, Z.H.;Zhang, Y.J.;Chae, M.S.;Park, B.C.;Kim, Y.S.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2008.05a
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    • pp.333-336
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    • 2008
  • There are many different kinds of forming processes to make a tubular product such as hydroforming and tube drawing. However, we should consider a better forming process in view point of energy consumption and $CO_2$ emission to save our earth. In this paper we have conducted FEM simulations to the various forming processes for sheet and tubular products to compare their energy consumptions. One example is tubular product and the other for drawn cup. From the comparisons of total energy for hydrofroming and tube sinking processes, hydroforming is consumed more energy than tube drawing. Also the cup drawing from sheet metal and tube sinking for the cup with flange indicate that the tube sinking is better than cup drawing of sheet metal in energy consumption.

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Recovery of Rare Earth Metal from Used Automotive Three-Way Catalyst (자동차용 폐 삼원촉매로부터의 희귀금속 회수공정 기술 동향)

  • Hong, Yeon Ki
    • Journal of Institute of Convergence Technology
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    • v.1 no.1
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    • pp.13-17
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    • 2011
  • The car industry is one of the technological applications which more rare earth metals employes as three-way catalysts. Therefore, the recovery of rare earth metals from the used automotive three-way catalysts could be important source to obtain these metals. This work presents the analysis of market and demand for rare earth metal in automotive three-way catalyst and introduces the dry and the wet processes for the recovery of rare earth metals from used three-way catalyst. Finally, the alternative methods to conventional wet processes was simply suggested based on the economic and ecological point of view.

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Analysis of 3-D Cutting Process with Single Point Tool

  • Lee, Young-Moon;Park, Won-Sik;Song, Tae-Seong
    • International Journal of Precision Engineering and Manufacturing
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    • v.1 no.1
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    • pp.15-21
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    • 2000
  • This study presents a procedure for analyzing chip-tool friction and shear processes in 3-D cutting with a single point tool. The edge of a single point tool including a circular nose is modified to an equivalent straight edge, thereby reducing the 3-D cutting with a single point tool to the equivalent of oblique cutting. Then, by transforming the conventional coordinate systems and using the measurements of three cutting force components, the force components on the rake face and shear plane of the equivalent oblique cutting system can be obtained. As a result, the chip-tool friction and shear characteristics of 3-D cutting with a single point tool can be assessed.

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Interference and Throughput in Spectrum Sensing Cognitive Radio Networks using Point Processes

  • Busson, Anthony;Jabbari, Bijan;Babaei, Alireza;Veque, Veronique
    • Journal of Communications and Networks
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    • v.16 no.1
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    • pp.67-80
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    • 2014
  • Spectrum sensing is vital for secondary unlicensed nodes to coexist and avoid interference with the primary licensed users in cognitive wireless networks. In this paper, we develop models for bounding interference levels from secondary network to the primary nodes within a spectrum sensing framework. Instead of classical stochastic approaches where Poisson point processes are used to model transmitters, we consider a more practical model which takes into account the medium access control regulations and where the secondary Poisson process is judiciously thinned in two phases to avoid interference with the secondary as well as the primary nodes. The resulting process will be a modified version of the Mat$\acute{e}$rn point process. For this model, we obtain bounds for the complementary cumulative distribution function of interference and present simulation results which show the developed analytical bounds are quite tight. Moreover, we use these bounds to find the operation regions of the secondary network such that the interference constraint is satisfied on receiving primary nodes. We then obtain theoretical results on the primary and secondary throughputs and find the throughput limits under the interference constraint.