• Title/Summary/Keyword: OBSERVER BIAS

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Estimating the State-of-Charge of Lithium-Ion Batteries Using an H-Infinity Observer with Consideration of the Hysteresis Characteristic

  • Xie, Jiale;Ma, Jiachen;Sun, Yude;Li, Zonglin
    • Journal of Power Electronics
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    • v.16 no.2
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    • pp.643-653
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    • 2016
  • The conventional methods used to evaluate battery state-of-charge (SOC) cannot accommodate the chemistry nonlinearities, measurement inaccuracies and parameter perturbations involved in estimation systems. In this paper, an impedance-based equivalent circuit model has been constructed with respect to a LiFePO4 battery by approximating the electrochemical impedance spectrum (EIS) with RC circuits. The efficiencies of approximating the EIS with RC networks in different series-parallel forms are first discussed. Additionally, the typical hysteresis characteristic is modeled through an empirical approach. Subsequently, a methodology incorporating an H-infinity observer designated for open-circuit voltage (OCV) observation and a hysteresis model developed for OCV-SOC mapping is proposed. Thereafter, evaluation experiments under FUDS and UDDS test cycles are undertaken with varying temperatures and different current-sense bias. Experimental comparisons, in comparison with the EKF based method, indicate that the proposed SOC estimator is more effective and robust. Moreover, test results on a group of Li-ion batteries, from different manufacturers and of different chemistries, show that the proposed method has high generalization capability for all the three types of Li-ion batteries.

COGNITIVE BIASES IN INTERPRETATION, EXPECTATION AND JUDGEMENT OF SOCIALLY ANXIOUS CHILDREN (사회불안 아동의 해석, 기대 및 판단에서의 인지 편향)

  • Yang, Yoon-Ran;Oh, Kyung-Ja
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.15 no.2
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    • pp.152-159
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    • 2004
  • Objective : The present study investigated the interpretation bias and expectation and judgemental bias of performance in socially anxious children. Method : Children with high social anxiety (n=18) and low social anxiety (n=16) were recruited through self-report and peer nomination, Participants performed three tasks to assess for cognitive bias. The first task measured interpretation of ambiguous social situations. The second task measured expectations regarding performance in a three minute impromptu speech. The third task assessed for judgemental bias via comparison between post-speech self rating and observer rating. Result : Children with high social anxiety did not differ significantly from low social anxiety children on the dependent measures assessing bias in interpretation, expectation and judgement. However, a significant difference was found in the judges' rating of children's performances on the speech task, with high social anxiety children obtaining significantly lower scores compared to low social anxiety children. Conclusion : The role of cognitive biases in the development and maintenance of social anxiety in children was discussed.

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The Kaiser Rocket Effect in Cosmology

  • Bahr-Kalus, Benedict
    • The Bulletin of The Korean Astronomical Society
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    • v.46 no.2
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    • pp.43.3-43.3
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    • 2021
  • The peculiar motion of the observer, if not (or only imperfectly) accounted for, is bound to induce a well-defined clustering signal in the distribution of galaxies. This spurious signal is related to the Kaiser rocket effect. We examined the amplitude of this effect and discuss possible implications for analysis and interpretation of future cosmological surveys. We found that it can in principle bias very significantly the inference of cosmological parameters, especially for primordial non-Gaussianity.

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Evluation of the DINAMAP 8100 Automated Blood Pressure monitor ; comparison with the Mercury Sphygmomanometer (수은 혈압계와 DINAMAP 8100 자동 혈압계의 혈압측정치 비교연구)

  • Kim Mee-Yeon;Choi Hee-Kang;Kim Nam-Jin
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.3 no.1
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    • pp.96-107
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    • 1996
  • Automated blood pressure monitors have gained acceptance in many clinical settings with the increasing demand, the accurate BP measuring devices reguire the need for validation. We have evaluated the Dinamap 8100, an oscillometric automated blood pressure monitor, using the Mercury sphygmomanometer as a reference. Comparison of sphygmomanometers was conducted 60 patients (30-Normotensive group, 30-Hypertensive group at Seoul National University Hospital. Two trained observers took measure blood pressure(systolic/diastolic) at the same time using the Dinamap 8100 on one arm and the Mercury on the other. For each measurement, the device was randomly selected from a group of devices repetively used for the experiment. Mean readings for systolic pressure with the Dinamap 8100 in normotensive group were lower(mean difference ; 4.26mmHg) than the Mercury type. Mean readings for systolic pressure with the Dinamap 8100 in hypertensive group were lower(mean difference ; 9.05mmHg) than the Mercury type. Mean readings for diastolic pressure with the Dinamap 8100 in normotensive group were lower (mean difference ; 7.46mmHg) than the Mercury type. Mean readings for diastolic pressure with the Dinamap 8100 in hypertensive group were lower(mean difference ; 9.03mmHg) than the Mercury type. We have found that blood pressure readings with the Dinamap 8100 were lower than those with the Mercury type. we are using the Mercury type in clinics, although it has observer bias and terminal digit preference. But the Dinamap 8100 is readily portable, simple to use, and capable of preventing observer bias and terminal digit preference. The Dinamap 8100 is acceptable for blood pressure determination in subjects who are normotensive or hypertensive ones.

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Interrater Reliability in the Content Analysis of Preparatory Information for Mechanically Ventilated Patients (인공호흡기 사용 환자들에게 제공된 예비적 정보에 대한 내용분석의 측정자간 신뢰도)

  • Kim Hwa-Soon
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.5 no.2
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    • pp.269-279
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    • 1998
  • In nursing research that the data is collected through clinical observation, analysis of clinical recording or coding of interpersonal interaction in clinical areas, testing and reporting interrater reliability is very important to assure reliable results. Procedures for interrater reliability in these studies should follow two steps. The first step is to determine unitizing reliability, which is defined as consistency in the identification of same data elements in the record by two or more raters reviewing the same record. Unitizing reliability have been rarely reported in previous studies. Unitizing reliability should be tested before progressing to the next step as precondition. Next step is to determine interpretive reliability. Cohen's kappa is a preferable method of calculating the extent of agreement between observer or judges because it provides beyond-chance agreement. Despite its usefulness, kappa can sometimes present paradoxical conclusions and can be difficult to interpret. These difficulties result from the feature of kappa which is affected in complex ways by the presence of bias between observers and by true prevalence of certain categories. Therefore, percentage agreement should be reported with kappa for adequate interpretation of kappa. The presence of bias should be assessed using the bias index and the effect of prevalence should be assessed using the prevalence index. Researchers have been reported only global reliability reflecting the extent to which coders can consistently use the whole coding system across all categories. Category-by-category reliability also need to be reported to inform the possibility that some categories are harder to use than others.

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A Quantitative Vigilance Measuring Model by Fuzzy Sets Theory in Unlimited Monitoring Task

  • Liu, Cheng-Li;Uang, Shiaw-Tsyr;Su, Kuo-Wei
    • Industrial Engineering and Management Systems
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    • v.4 no.2
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    • pp.176-183
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    • 2005
  • The theory of signal detection has been applied to a wide range of practical situation for a long time, including sonar detection, air traffic control and so on. In general, in this theory, sensitivity parametric index d' and bias parametric index $\beta$ are used to evaluated the performance of vigilance. These indices use observer's response "hit" and "false alarm" to explain and evaluate vigilance, but not considering reaction time. However, the reaction time of detecting should be considered in measuring vigilance in some supervisory tasks such as unlimited monitoring tasks (e.g., supervisors in nuclear plant). There are some researchers have used the segments of reaction time to generate a pair of probabilities of hit and false alarm probabilities and plot the receiver operating characteristic curve. The purpose of this study was to develop a quantitative vigilance-measuring model by fuzzy sets, which combined the concepts of hit, false alarm and reaction time. The model extends two-values logic to multi-values logic by membership functions of fuzzy sets. A simulated experiment of monitoring task in nuclear plant was carried out. Results indicated that the new vigilance-measuring model is more efficient than traditional indices; the characteristics of vigilance would be realized more clearly in unlimited monitoring task.

Automatic Color Recognition System for Stockigt Sizing Test (I) - Bias of Stockigt sizing test based on observer's subjectiveness - (스테키히트 시험용 자동 발색 인지 시스템 개발을 위한 기초연구(I) - Stockigt 사이즈도 시험법에 영향을 주는 요인 분석 -)

  • 김재옥;김철환;박종열
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.36 no.1
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    • pp.1-8
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    • 2004
  • One of the most frequently used method for measurement of the degree of sizing (viz., hydrophobicity) is the Stockigt test. However, the Stockigt test was influenced by various factors such as dropping height, dropping amount, dropping speed and viewing angle. The resultant data of the sizing degree on the same specimen also varied according to different testers. Thus, the Stockigt test should be modified to be regarded as a highly reliable and reproducible standard method. For modifying the Stockigt test, it was required to quantify red coloration by reaction between 1% ferric chloride and 2% ammonium thiocyante during Stockigt testing. The cameras capturing the serial images during the red coloration process were the CMOS (Complementary Metal Oxide Semiconductor)-type and CCD (Charge Coupled Device)-type cameras. For measurement based on KS M 7025, the CCD-type camera must be used due to its high resolution, and on the other hand, for measurement based on Tappi Useful Method 429, the CMOS-type camera may be used owing to its low resolution. It was needed to covert the RGB values of a droplet image into HSV(Hue, Saturation, and Value) values because the human eyes are much closer to HSV than RGB. Among HSV values, the Hue value was accepted as the most reliable index consistent with the red coloration process by excluding the surrounding conditions such as light, tester's movement etc.

Managing Complications in Abdominoplasty: A Literature Review

  • Vidal, Pedro;Berner, Juan Enrique;Will, Patrick A.
    • Archives of Plastic Surgery
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    • v.44 no.5
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    • pp.457-468
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    • 2017
  • Background Abdominoplasty, with or without liposuction, is among the most frequently performed aesthetic procedures. Its main objective is to improve the body contour by means of excising redundant skin and fat tissue. Although abdominoplasty is considered a safe procedure with high satisfaction rates, intraoperative and postoperative complications can become a challenge for the surgical team. The aim of this article is to offer a synopsis of the most common complications arising after abdominoplasty, along with evidence-based guidelines about how to prevent and treat them. Methods A systematic MEDLINE search strategy was designed using appropriate Medical Subject Headings (MeSH) terms, and references were scanned for further relevant articles. Results According to the published case series, local complications are considerably more common than complications with systemic repercussions. Approximately 10% to 20% of patients suffer a local complication following abdominoplasty, while fewer than 1% suffer a systemic complication. Prevention and management strategies are critically discussed for complications including seroma, haematoma, infection, skin necrosis, suture extrusions, hypertrophic scars, neurological symptoms, umbilical anomalies, deep venous thrombosis and pulmonary thromboembolism, respiratory distress, and death. Conclusions The complications of abdominoplasty vary in severity and in the impact they have on the aesthetic outcomes. Recommendations for prevention and management are based on various levels of evidence, with a risk of observer bias. However, most complications can be treated appropriately following the current standards, with satisfactory results.

Blood pressure measurements and hypertension in infants, children, and adolescents: from the postmercury to mobile devices

  • Lim, Seon Hee;Kim, Seong Heon
    • Clinical and Experimental Pediatrics
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    • v.65 no.2
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    • pp.73-80
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    • 2022
  • A mercury sphygmomanometer (MS) has been the gold standard for pediatric blood pressure (BP) measurements, and diagnosing hypertension is critical. However, because of environmental issues, other alternatives are needed. Noninvasive BP measurement devices are largely divided into auscultatory and oscillometric types. The aneroid sphygmomanometer, the currently used auscultatory method, is inferior to MS in terms of limitations such as validation and regular calibration and difficult to apply to infants, in whom Korotkoff sounds are not audible. The oscillometric method uses an automatic device that eliminates errors caused by human observers and has the advantage of being easy to use; however, owing to its measurement accuracy issues, the development of an international validation protocol for children is important. The hybrid method, which combines the auscultatory and electronic methods, solves some of these problems by eliminating the observer bias of terminal digit preference while maintaining measurement accuracy; however, the auscultatory method remains limited. As the age-related characteristics of the pediatric group are heterogeneous, it is necessary to reconsider the appropriate BP measurement method suitable for this indication. In addition, the mobile application-based BP measurement market is growing rapidly with the development of smartphone applications. Although more research is still needed on their accuracy, many experts expect that mobile application-based BP measurement will effectively reduce medical costs due to increased ease of access and early BP management.

Punitiveness Toward Defendants Accused of Same-Race Crimes Revisited: Replication in a Different Culture (동인종 범죄로 기소된 피고인에 대한 엄벌주의적 판단의 재고찰: 다른 문화에서의 적용)

  • Lee, Jungwon;Khogali, Mawia;Despodova, Nikoleta M.;Penrod, Steven D.
    • Korean Journal of Forensic Psychology
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    • v.11 no.1
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    • pp.37-61
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    • 2020
  • Lee, Khogali, Despodova, and Penrod (2019) demonstrated that American participants whose races are different from a defendant and a victim rendered more punitive judgments against the defendant in a same-race crime (e.g., White observer-Black defendant-Black victim) compared to a cross-race crime (e.g., White observer-Black defendant-Hispanic victim). The aim of the current study was to test the replicability of their findings in a different country-South Korea. Study 1a failed to replicate the race-combination effect in South Korea with three new moderators-case strength, defendant's use of violence, and race salience. Study 1b was conducted with the same design of Study 1a in the United States to examine whether the failure of the replication in Study 1a was due to cultural differences between South Korea and the United States. However, Study 1b also failed to replicate the race-combination effect. Study 2 conducted a meta-analytic review of the data from Lee et al.'s (2019) study, along with the data from Study 1a and 1b and revealed that the race-salience manipulation in Study 1a and 1b might have caused the null results. We conclude that when people' races are different from both a defendant and a victim, they are likely to render more punitive judgments against the defendant in a same-race crime than a cross-race crime. However, the race-combination effect is only sustained when race-relevant issues are not salient in the crime.

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