• Title/Summary/Keyword: deviation of leads

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Measurement of maximum deviation of leads using partial image of SMD mounted on PCB (PCB에 장착된 SMD 의 부분영상을 이용한 리드의 최대 벗어난 양의 측정)

  • Shin, Dong-Won;You, Jun-Ho
    • Journal of Institute of Control, Robotics and Systems
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    • v.5 no.6
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    • pp.698-704
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    • 1999
  • There are several types of defects of SMDs mounted on PCB, that is, missing components, misalignment, wrong parts and poor solder joints. This research study mainly focuses on measuring of deviation of SMD leads using the partial image of component, not using the full image. This processing based on the partial image has the advantage of the reduction in calculation time compared to the full image. Since position of lead is calculated with respect of the reduction in calculation time compared to the full image. Since position of lead is calculated with respect to pad, the accuracy of the system is not dependent on percise positioning stage. The grabbed image of gray scale is converted into binary format using a cutomatic threshold. After small fragments in the image is removed by a series of morphology operations such as opening and closing, the centroids of PCB pads and SMD leads is obtained together with labeling of blobs. Translational shift and rotationial angle of SMD are succedingly estimated using above information and chip data. The expression that can calculate the maximum deviation of leads with respect to PCB pads has been derived, and inferior mounting of SMD is judged by a given criterion. Some experiments have been executed to verify this measuring scheme.

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Algorithm for Accuracy Interpretation of Multilead ECG (멀티리드 심전도의 정확한 판독 알고리즘)

  • 김민수;조영창;서희돈
    • Proceedings of the IEEK Conference
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    • 2002.06e
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    • pp.265-268
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    • 2002
  • For accurate interpretation, ECG signal is measured by using 12 leads method. We look shape of Measured ECG signal and decide whether interpretation is accurate or not. In this paper, we propose new effective fuzzy decision system which uses fuzzy rules and membership functions for more accurate of ECG wave. We used PR interval, QRS interval and QRS axis as conditional variables for designing fuzzy rules. And decision rule of conclusion variable is determined by (sinus rhythm), (sinus rhythm+left deviation), (sinus rhythm+right deviation) and (sinus rhythm+negative axis). Experimental results showed our system made numerically easy decision possible and had advantage of simple design method.

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Probabilistic stability analysis of underground structure using stochastic finite element method

  • Na, Sang-Min;Moon, Hyun-Koo
    • 한국지구물리탐사학회:학술대회논문집
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    • 2003.11a
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    • pp.192-197
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    • 2003
  • It can be said that rock mass properties are characterized not by a mean value but by values with variation due to its characteristic uncertainty. This characteristic is one of the most important parts for the design of underground structures, but yet to be fully examined. Stochastic finite element method (SFEM) has been developed in order to take the randomness of structural systems into account. Using SFEM, the response variability of structural system can be obtained and it leads probabilistic stability of structure to be analyzed. In this study, displacements response variability of circular opening with hydrostatic stress field are analyzed in terms of rock mass properties having a certain mean and a standard deviation using the SFEM. The analyzed response variability shows that the necessity of probabilistic stability analysis of underground structures using reliable mean value and standard deviation of deformation modulus.

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Exact Solutions of Fuzzy Goal Programming Problems using $\alpha-cut$ Representations

  • Hong, Dug-Hun;Hwang, Chang-Ha
    • Journal of the Korean Data and Information Science Society
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    • v.15 no.2
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    • pp.457-465
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    • 2004
  • Ramik[7] introduced a fuzzy goal programming (FGP)problem that generalizes a standard goal programming (GP) problem with fuzzy alternatives, fuzzy objective functions and fuzzy deviation functions for measuring the deviation between attained and desired goals being fuzzy. However, it is known that this FGP tends to produce an approximate solution since it uses an approximate fuzzy multiplication operation to solve the resultant fuzzy model. In this paper, we show that this FGP sometimes leads to the wrong decision. We also propose a procedure that gets the exact solution to overcome these problems. The method is based on $T_M$ (min norm)-based fuzzy operations using $\alpha-cut$ representations. We consider the same example as used in Ramik and investigate how our procedures are compared to Ramik's.

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Event-related potentials reveal neural signatures of cross-modal interaction between visual and tactile stimulation (유발전위신호(ERP)를 통한 시각과 촉각 통합작용의 신경생리적 특징 분석)

  • Ju, Yu-Mi;Lee, Kyoung-Min
    • Proceedings of the Korean Society for Cognitive Science Conference
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    • 2010.05a
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    • pp.48-54
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    • 2010
  • INTRODUCTION Interaction between temporal events at the millisecond level is important for visual and tactile interaction. OBJECT The aim of the present study is to identify any neural signature, as reflected in event-related potentials (ERP), for the integrative processes when the two sensory modalities are stimulated in synchrony as opposed to when they are stimulated separately. METHOD The basic strategy was to compare ERP signals obtained with simultaneous visual and tactile stimulation with a linear summation of ERP patterns obtained with each modality stimulated separately. Condition were presented, paired with various stimulus-onset-asynchronies (SOA) ranging from - 300 ms (tactile-first) to 300 ms (visual-first), and in trials where only one modality was stimulated alone. RESULT A positive deviation was located in observed ERP at C4 electrode (contralateral to the stimulated hand) at 200-400 ms, in comparison to the predicted ERP. The deviation was present at all SOAs other than -300ms (tactile-first) and 300 ms (visual-first). There was also a positive deviation at occipital leads at the 50-ms SOA (visual-first) trials. DISCUSSION It suggested that neural signatures of cross-modal integration occur within a limited time-window. The deviations were specifically localized at the contralateral somatosensory and visual cortices, indicating that the integration happens at or before the level of the primary cortices.

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Numerical Simulation of Failure Mechanism of Space Frame Structure by Nonlinear Dynamic Analysis (비선형 동적해석을 통한 입체라멘 교각의 파괴 메카니즘 모사)

  • 김익현
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2000.10a
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    • pp.348-355
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    • 2000
  • The characteristics on non linear behavior and the failure mechanism of RC space frame structure serving railway under seismic action have been investigated by numerical analysis in time domain. The structure concerned is modeled in 3 dimensional extent and RC frame elements with fibers are employed. Fibers are characterized as RC one and PL one to distinguish different energy release after cracking. Due to deviation of mass center and stiffness center of entire structure the complex behavior under seismic action is shown. The excessive shear force is concentrated on the pier beside flexible one relatively, which leads to failure of bridge concerned.

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Luminescence and Crystal Field Parameters of the Na₃[Eu(ODA)₃]·7H₂O Complex in Single Crystalline State

  • 강준길;윤수경;손영구;김종구
    • Bulletin of the Korean Chemical Society
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    • v.18 no.8
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    • pp.861-864
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    • 1997
  • Luminescence spectrum of Na3[Eu(ODA)3]·7H2O (ODA≡oxydiacetato) was measured at various temperatures. The characteristic band splitting within 5D0→7FJ (J = 1, 2, 3 and 4) were phenomenologically simulated by using crystal field theory. The set of crystal field parameters reproduces the emission lines in a satisfactory manner with a rms deviation of 21.4 cm-1. It leads the reliable assignment of the luminescence bands and the energy level scheme of 7FJ (J = 1, 2, 3 and 4) multiplets.

Application of Detrended Fluctuation Analysis of Electroencephalography during Sleep Onset Period (수면발생과정의 뇌파를 대상으로한 탈경향변동분석의 적용)

  • Park, Doo-Heum;Shin, Chul-Jin
    • Korean Journal of Biological Psychiatry
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    • v.19 no.1
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    • pp.65-69
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    • 2012
  • Objectives : Much is still unknown about the neurophysiological mechanisms or dynamics of the sleep onset process. Detrended fluctuation analysis (DFA) is a new tool for the analysis of electroencephalography (EEG) that may give us additional information about electrophysiological changes. The purpose of this study is to analyze long-range correlations of electroencephalographic signals by DFA and their changes in the sleep onset process. Methods : Thirty channel EEG was recorded in 61 healthy subjects (male:female=34:27, age=$27.2{\pm}3.0$ years). The scaling exponents, alpha, were calculated by DFA and compared between four kinds of 30s sleep-wakefulness states such as wakefulness, transition period, early sleep, and late sleep (stage 1). These four states were selected by the distribution of alpha and theta waves in O1 and O2 electrodes. Results : The scaling exponents, alpha, were significantly different in the four states during sleep onset periods, and also varied with the thirty leads. The interaction between the sleep states and the leads was significant. The means (${\pm}$ standard deviation) of alphas for the states were 0.94 (${\pm}0.12$), 0.98 (${\pm}0.12$), 1.10 (${\pm}0.10$), 1.07 (${\pm}0.07$) in the wakefulness, transitional period, early sleep and late sleep state respectively. The mean alpha of anterior fifteen leads was greater than that of posterior fifteen leads, and the two regions showed the different pattern of changes of the alpha during the sleep onset periods. Conclusions : The characteristic findings in the sleep onset period were the increasing pattern of scaling exponent of DFA, and the pattern was slightly but significantly different between fronto-temporal and parieto-occipital regions. It suggests that the long-range correlations of EEG have a tendency of increasing from wakefulness to early sleep, but anterior and posterior brain regions have different dynamical process. DFA, one of the nonlinear analytical methods for time series, may be a useful tool for the investigation of the sleep onset period.

Geostatistical algorithm for evaluation of primary and secondary roughness

  • Nasab, Hojat;Karimi-Nasab, Saeed;Jalalifar, Hossein
    • Geomechanics and Engineering
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    • v.24 no.4
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    • pp.359-370
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    • 2021
  • Joint roughness is combination of primary and secondary roughness. Ordinarily primary roughness is a geostatistical part of a joint surface that has a periodic nature but secondary roughness or unevenness is a statistical part of that which have a random nature. Using roughness generating algorithms is a useful method for evaluation of joint roughness. In this paper after determining geostatistical parameters of the joint profile, were presented two roughness generating algorithms using Mount-Carlo method for evaluation of primary (GJRGAP) and secondary (GJRGAS) roughness. These based on geostatistical parameters (range and sill) and statistical parameters (standard deviation of asperities height, SDH, and standard deviation of asperities angle, SDA) for generation two-dimensional joint roughness profiles. In this study different geostatistical regions were defined depending on the range and SDH. As SDH increases, the height of the generated asperities increases and asperities become sharper and at a specific range (a specific curve) relation between SDH and SDA is linear. As the range in GJRGAP becomes larger (the base of the asperities) the shape of asperities becomes flatter. The results illustrate that joint profiles have larger SDA with increase of SDH and decrease of range. Consequencely increase of SDA leads to joint roughness parameters such Z2, Z3 and RP increases. The results showed that secondary roughness or unevenness has a great influence on roughness values. In general, it can be concluded that the shape and size of asperities are appropriate parameters to approach the field scale from the laboratory scale.

Forefoot disorders and conservative treatment

  • Park, Chul Hyun;Chang, Min Cheol
    • Journal of Yeungnam Medical Science
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    • v.36 no.2
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    • pp.92-98
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    • 2019
  • Forefoot disorders are often seen in clinical practice. Forefoot deformity and pain can deteriorate gait function and decrease quality of life. This review presents common forefoot disorders and conservative treatment using an insole or orthosis. Metatarsalgia is a painful foot condition affecting the metatarsal (MT) region of the foot. A MT pad, MT bar, or forefoot cushion can be used to alleviate MT pain. Hallux valgus is a deformity characterized by medial deviation of the first MT and lateral deviation of the hallux. A toe spreader, valgus splint, and bunion shield are commonly applied to patients with hallux valgus. Hallux limitus and hallux rigidus refer to painful limitations of dorsiflexion of the first metatarsophalangeal joint. A kinetic wedge foot orthosis or rocker sole can help relieve symptoms from hallux limitus or rigidus. Hammer, claw, and mallet toes are sagittal plane deformities of the lesser toes. Toe sleeve or padding can be applied over high-pressure areas in the proximal or distal interphalangeal joints or under the MT heads. An MT off-loading insole can also be used to alleviate symptoms following lesser toe deformities. Morton's neuroma is a benign neuroma of an intermetatarsal plantar nerve that leads to a painful condition affecting the MT area. The MT bar, the plantar pad, or a more cushioned insole would be useful. In addition, patients with any of the above various forefoot disorders should avoid tight-fitting or high-heeled shoes. Applying an insole or orthosis and wearing proper shoes can be beneficial for managing forefoot disorders.