• Title/Summary/Keyword: observer effects

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Seamless Transition Strategy for Wide Speed-Range Sensorless IPMSM Drives with a Virtual Q-axis Inductance

  • Shen, Hanlin;Xu, Jinbang;Yu, Baiqiang;Tang, Qipeng;Chen, Bao;Lou, Chun;Qiao, Yu
    • Journal of Power Electronics
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    • v.19 no.5
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    • pp.1224-1234
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    • 2019
  • Hybrid rotor position estimation methods that integrate a fundamental model and high frequency (HF) signal injection are widely used for the wide speed-range sensorless control of interior permanent-magnet synchronous machines (IPMSMs). However, the direct transition of two different schemes may lead to system fluctuations or system instability since two estimated rotor positions based on two different schemes are always unequal due to the effects of parameter variations, system delays and inverter nonlinearities. In order to avoid these problems, a seamless transition strategy to define and construct a virtual q-axis inductance is proposed in this paper. With the proposed seamless transition strategy, an estimated rotor position based on a fundamental model is forced to track that based on HF signal injection before the transition by adjusting the constructed virtual q-axis inductance. Meanwhile, considering that the virtual q-axis inductance changes with rotor position estimation errors, a new observer with a two-phase phase-locked loop (TP-PLL) is developed to accurately obtain the virtual q-axis inductance online. Furthermore, IPMSM sensorless control with maximum torque per ampere (MTPA) operations can be tracked automatically by selecting the proper virtual q-axis inductance. Finally, experimental results obtained from an IPMSM demonstrate the feasibility of the proposed seamless transition strategy.

Effect of object position in the field of view and application of a metal artifact reduction algorithm on the detection of vertical root fractures on cone-beam computed tomography scans: An in vitro study

  • Nikbin, Ava;Kajan, Zahra Dalili;Taramsari, Mehran;Khosravifard, Negar
    • Imaging Science in Dentistry
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    • v.48 no.4
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    • pp.245-254
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    • 2018
  • Purpose: To assess the effects of object position in the field of view (FOV) and application of a metal artifact reduction (MAR) algorithm on the diagnostic accuracy of cone-beam computed tomography (CBCT) for the detection of vertical root fractures(VRFs). Materials and Methods: Sixty human single-canal premolars received root canal treatment. VRFs were induced in 30 endodontically treated teeth. The teeth were then divided into 4 groups, with 2 groups receiving metal posts and the remaining 2 only having an empty post space. The roots from different groups were mounted in a phantom made of cow rib bone, and CBCT scans were obtained for the 4 different groups. Three observers evaluated the images independently. Results: The highest frequency of correct diagnoses of VRFs was obtained with the object positioned centrally in the FOV, using the MAR algorithm. Peripheral positioning of the object without the MAR algorithm yielded the highest sensitivity for the first observer (66.7%). For the second and third observers, a central position improved sensitivity, with or without the MAR algorithm. In the presence of metal posts, central positioning of the object in the FOV significantly increased the diagnostic sensitivity and accuracy compared to peripheral positioning. Conclusion: Diagnostic accuracy was higher with central positioning than with peripheral positioning, irrespective of whether the MAR algorithm was applied. However, the effect of the MAR algorithm was more significant with central positioning than with peripheral positioning of the object in the FOV. The clinical experience and expertise of the observers may serve as a confounder in this respect.

A Case Study for the Improvement of Communication and Self-esteem in the Electronic device - Sexual offenders' Couple Counseling -Based on Satire's Empirical Growth Model- (전자장치부착 성폭력범죄자의 부부상담이 의사소통 및 자아존중감 향상을 위한 사례연구 -사티어 경험적 성장모델을 중심으로-)

  • Lee, Kil-ku
    • Journal of Digital Convergence
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    • v.17 no.4
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    • pp.327-334
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    • 2019
  • This study is a case study of couple counseling case applying Satir Empirical Growth Model to improve the communication and self - esteem of the sexual offenders who are attached to the electronic devices requested by the representative at the ${\bigcirc}{\bigcirc}$ Compliance Support Center. The counseling process was carried out in this center counseling room for 120 minutes from March to June 2017 once a week for 5 times in total. To validate the effects of this study, researchers and observer-centered techniques were used as subjective evaluations. Based on the results of the study, the following conclusions were obtained. The self - esteem and communication change of the subjects with sexual violence electronic devices were found to be positive. This suggests that there is a significant effect in suggesting the possibility of using the marital counseling in the practice of the correctional facility.

A Convergent Approach to Gain a Better Understanding of Alzheimer's Disease: Stereoscopic Vision (융복합적 접근을 통한 알츠하이머형 치매의 이해 증진 : 양안 지각)

  • Kim, Nam-Gyoon;Lee, Ho-Won
    • Journal of the Korea Convergence Society
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    • v.10 no.5
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    • pp.103-110
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    • 2019
  • The present study investigated the effects of AD on stereoscopic vision. Sixty participants (20 AD patients, 20 mild cognitive impairment patients, 20 healthy elderly controls) participated in the study. Two cubes, one on the left and the other on the right of the center of the monitor, appeared at varying distances from the observer with their relative distances controlled in two disparity conditions (absolute vs relative disparity) combined with two disparity directions (crossed vs uncrossed disparity). Participants identified the object that appeared closer to them. Results demonstrated comparable performance with all three groups performing accurately, suggesting that the effect of AD on stereopsis is negligible. Discussion focused on brain pathology affected by AD involving high level visual processing.

Interobserver agreement for detecting Hill-Sachs lesions on magnetic resonance imaging

  • Alkaduhimi, Hassanin;Saarig, Aimane;Amajjar, Ihsan;van der Linde, Just A.;van Wier, Marieke F.;Willigenburg, Nienke W.;van den Bekerom, Michel P.J.
    • Clinics in Shoulder and Elbow
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    • v.24 no.2
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    • pp.98-105
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    • 2021
  • Background: Our aim is to determine the interobserver reliability for surgeons to detect Hill-Sachs lesions on magnetic resonance imaging (MRI), the certainty of judgement, and the effects of surgeon characteristics on agreement. Methods: Twenty-nine patients with Hill-Sachs lesions or other lesions with a similar appearance on MRIs were presented to 20 surgeons without any patient characteristics. The surgeons answered questions on the presence of Hill-Sachs lesions and the certainty of diagnosis. Interobserver agreement was assessed using the Fleiss' kappa (κ) and percentage of agreement. Agreement between surgeons was compared using a technique similar to the pairwise t-test for means, based on large-sample linear approximation of Fleiss' kappa, with Bonferroni correction. Results: The agreement between surgeons in detecting Hill-Sachs lesions on MRI was fair (69% agreement; κ, 0.304; p<0.001). In 84% of the cases, surgeons were certain or highly certain about the presence of a Hill-Sachs lesion. Conclusions: Although surgeons reported high levels of certainty for their ability to detect Hill-Sachs lesions, there was only a fair amount of agreement between surgeons in detecting Hill-Sachs lesions on MRI. This indicates that clear criteria for defining Hill-Sachs lesions are lacking, which hampers accurate diagnosis and can compromise treatment.

Effects of Woobangja on Anti-allergic Inflammation (우방자(牛蒡子)가 항알러지 염증반응에 미치는 영향)

  • Kim, Deog-Gon;Lee, Jin-Young;Nam, Ji-Young
    • The Journal of Pediatrics of Korean Medicine
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    • v.20 no.1
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    • pp.241-255
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    • 2006
  • Objective : Allergic Inflammation is related with secretion of Cytokine. This study was performed to examine the effects of Woobangja on anti-allergic inflammation. Method : While macrophage 264.7cells was chosen as a normal group a control group was classified into three groups. One was stimulated with LPS. and another was pretreated with Woobangja for 1 hour. The third was pretreated with gydrocortisone for 1 hour. After the pretreatment, macrophage were incubated with lipopolysaccharide(LPS) 100 ng/ml for 12h and media collected and $TNF-{\alpha}$, IL-6, $IL-1{\beta}$, IL-10 concentration in supernatants were measured each by Enzyme linked immuno-sorbent assay. Woobangja were used $50\;{\mu}g/ml$, $100\;{\mu}g/ml$, $250\;{\mu}g/ml$, $500\;{\mu}g/ml$, 1 mg/ml. Hydrocortisones were used respectively $10^{-8}\;M$,$10^{-7}\;M$,$10^{-6}\;M$,$10^{-5}\;M$,$10^{-4}\;M$. Results : Woobangja showed inhibitory effect on $TNF-{\alpha}$ by LPS-stimulated macrophage 264.7. The inhibitory effect was most significant in 1mg/ml(p<0.01), and has increased according to the number of doses. Woobangja also showed inhibitory effect on IL-10 by LPS-stimulated macrophasg 264.7. The inhibitory effect was most significant in $100\;{\mu}g/ml$, and was not in a dose-dependent manner as Hydrocortisone group. Woobangja and Hydrocortison showed contrary effect on $IL-1{\beta}$ in al five concentration(p<0.01), and at the lowest concentration ($50\;{\mu}g/ml$) the level of $IL-1{\beta}$ was the lowest. On the other hand hydrocortison was observed to have inhibitory effect on $IL-1{\beta}$ in all five concentration(p<0.01). IL-6 was inhibited by hydrocortison in a roughly dose-dependent manner, but was not inhibited by Woobangja. On the contrary Woobangja obviously increased the expression of $IL-1{\beta}$ in all five concentration(p<0.01), but it was not related with concentrations. Conclusion : 1. Woobangja does significantly inhibit the expression of $TNF-{\alpha}$ by LPS-stimulated macrophage 264.7. 2. Woobangja does significantly increse the expression of IL-6 by LPS-stimulated macrophage 264.7. 3. Woobangja does significantly increse the expression of $IL-1{\beta}$ by LPS-stimulated macrophage 264.7. 4. Woobangja does significantly inhibit the expression of IL-10 by LPS-stimulated macrophage 264.7. 5. Woobangja is observer to have anti-allergic inflammatory effect through inhibiting inflammatory cytokine.

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The Implication of Bandura's Vicarious Reinforcement in Observational Learning for Christian Education (관찰학습에서의 반두라 대리강화에 대한 기독교교육적 함의)

  • Lee, Jongmin
    • Journal of Christian Education in Korea
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    • v.61
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    • pp.81-107
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    • 2020
  • This study reviews Bandura's vicarious reinforcement in observational learning process and implies this concept into Christian education in terms of spiritual role modeling. The first part of this study answers three questions: "what is vicarious reinforcement?" "how does vicarious reinforcement take place in observational learning?" and "how does vicarious reinforcement affect observer's behavior change?" Bandura conceptualizes the learning process with observational learning and imitative or non-imitative performance. Based on this concept, Bandura define the roles of vicarious reinforcement in the four steps of observational learning process: attention, retention, motor reproduction, and motivational process. Also, the three effects of vicarious reinforcements are explained in the following categories: the observational learning effect, inhibitory or disinhibitory effects, and eliciting effect. Adapting the structure of observational learning theory in terms of the effect of vicarious reinforcement and the function of role models, the second part of this study examines the biblical concept of imitation of Christ and the modeling strategy of discipleship. Especially Paul's spiritual role model serves as positive vicarious reinforcement for the Christian believers to perform the desired behaviors. Also, Paul's condemnation serves as explicit negative vicarious reinforcement. Then, the last part of this study covers the implication of these findings from observational learning and empirical studies in terms of spiritual role modeling to Christian education.

Effects of Bispectral Index Monitoring Based Sedative Administration on Conscious Sedation, Physiological Stability and Recovery Time in Patients Receiving Endoscopic Submucosal Dissection (이중분광계수 모니터기반 진정제 투여가 내시경 점막하 박리술 환자의 의식하 진정상태, 생리적 안정성 및 회복시간에 미치는 효과)

  • Lee, Mi Jeong;Hwang, Moon Sook;Lim, Hyun Sook;Park, Mi Ok;Huh, Ji Won;Kang, Ki Joo;Kim, Jae Jun;Cho, Myung Sook
    • Journal of Korean Clinical Nursing Research
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    • v.18 no.2
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    • pp.284-295
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    • 2012
  • Purpose: This study was done to clarify effects of bispectral index monitoring sedative administration, compared to MOAA/S (Modified Observer's Assessment of Alertness and Sedation), on conscious sedation, physiological stability and recovery time for patients undergoing endoscopic submucosal dissection. Methods: Participants In this study were patients who underwent endoscopic submucosal dissection because of early gastric cancer. Participants were assigned randomly to an experimental group receiving sedatives based on bispectral index monitoring or to a control group with the MOAA/S instrument. Movements, belching, memory, pain, discomfort, physiological stability (MBP, PR, $SpO_2$), and recovery time were measured during the treatment and recovery. Data were analyzed using Spearman partial correlation coefficient analysis, Mixed model and Wilcoxon rank sum test to determine differences in the parameters. Results: There were no statistically significant differences between the two groups for conscious sedation(movement, belching, memory, pain, or discomfort), physiological stability and recovery time. Conclusion: The results of this study indicate that no differences were found between the two types of monitoring. Thus, use of a bispectral index monitor in clinical practice enabling medical staff to readily assess the conscious sedation of for these patients is expected to be increasingly used as an objective assessment tool for conscious sedation for patient safety.

Effects of Butorphanol on Behavior after Intestinal Anastomosis in Dogs (Butorphanol의 투여가 장문합술 후 개의 행동에 미치는 영향)

  • Koo Ja-min;Lee Hee-chun;Chang Hong-hee;Seong Yong-jeung;Lee Hyo-jong;Yeon Seong-chan
    • Journal of Veterinary Clinics
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    • v.22 no.1
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    • pp.6-15
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    • 2005
  • This study was performed to investigate non-invasive behavioral pain assessment of dogs after surgery, and the analgesic effects of butorphanol after intestinal anastomosis in dogs. In this study, five dogs in the Control Group were anesthetized, but did not undergo surgery. Five dogs in the Analgesic Group were undergone intestinal anastomosis and treated with butorphanol. Five dogs in the Non-analgesic Group were also undergone intestinal anastomosis without analgesic treatment. The dogs in the Analgesic Group received butorphanol (0.4 mg/kg, IM) before and immediately after operation, while dogs in Control and Non-analgesic Groups received isovolumetric doses of sterile saline. The behavior of dogs were videotaped for 400 mins after anesthesia, during which time a researcher interacted with the dog once per each 80 mins. At each interaction, the researcher recorded behavioral pain score, using University of Melbourne Pain Scale. Interactive and non-interactive behaviors were observed and quantitated by a single observer using focal continuous sampling method. Vocalizations were obtained during 400 mins after anesthesia, and duration of call, intensity, pitch, 1-4 Formant were analyzed. Surgery affected an increasing of pain score. During interactions with researcher, greeting behaviors were decreased after surgery. Differences between Analgesic group given analgesic or that given a placebo drug were readily understood using quantitative behavioral measurements and vocalization. Significant difference between Analgesic group given butorphanol or that the given placebo drug was apparent(p< 0.05).

In-vivo Studies on Effect of Lipo-PGE1 on Neoangiogenesis of Composite Graft in a Rabbit Model (가토모델에서 Lipo-PGE1이 복합조직이식편의 미세혈관신생에 미치는 영향)

  • Park, Ji-Ung;Eo, Su-Rak;Cho, Sang-Hun;Choi, Jong-Sun;Kim, Eo-Jin
    • Archives of Plastic Surgery
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    • v.37 no.6
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    • pp.721-725
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    • 2010
  • Purpose: The survival of composite graft is dependent on three steps, (1) plasmatic imbibitions, (2) inosculation, and (3) neovascularization. Among the many trials to increase the survival rate of composite graft, prostaglandin E1 (PGE1) has beneficial effects on the microcirculatory level with vasodilating, antithrombotic, anti-inflammatory and neoangiogenic properties. Lipo-PGE1 which is lipid microspheres containing PGE1 had developed to compensate the systemic and local side effects of PGE1. This study was proposed to determine whether Lipo-PGE1 administration enhanced the survival of composite graft through neovascularization quantitatively in a rabbit ear model. Methods: Fourteen New Zealand White Rabbits each weighing 3~4 kg were divided in two groups: (1) intravenous Lipo-PGE1 injection group and (2) control group. A $2{\times}1\;cm$ sized, full-thickness rectangular composite graft was harvested in each auricle. Then, the graft was reaaproximated in situ using a 5-0 nylon suture. For the experimental group, $3{\mu}g$/kg/day of Lipo-PGE1 ($5{\mu}g$/mL) was administered intravenously through the marginal vein of the ear for 14 days. The control group was received no pharmacologic treatment. On the 14th postoperative day, composite graft of the ear was harvested and immunochemistry staining used Monoclonal mouse anti-CD 31 antibody was performed. Neoangiogenesis was quantified by counting the vessels that showed luminal structures surrounded by the brown color-stained epithelium and counted from 10 random high-power fields (400x) by independent blinded observer. Statistical analysis (Wilcoxon Signed Ranks test for nonparametric data) was performed using SPSS v12.0, with values of p<0.05 considered significant. Results: The mean number of the microvessels was $15.48{\pm}8.65$ in the experimental group and $9.82{\pm}7.25$ in the control group (p=0.028). Conclusion: The use of Lipo-PGE1 facilitated the neoangiogenesis, resulted in the improvement of the survival rate of graft. On the basis of this results, we could support wider application of Lipo-PGE1 for more effective therapeutic angiogenesis and successful survival in various cases of composite graft in the human.