• Title/Summary/Keyword: Self-bias

검색결과 304건 처리시간 0.03초

A Structural Model Development of Health Insensitivity in Korean Adult (한국인 성인의 건강불감증 구조모형 구축)

  • Lee, Dong-Suk
    • Korean Journal of Adult Nursing
    • /
    • 제16권3호
    • /
    • pp.355-365
    • /
    • 2004
  • Purpose: The aims of this study were to develope a structural model of health insensitivity and to verify the model of health insensitivity. Method: There were three theoretical variables in the hypothetical model. The endogenous variable was health insensitivity which is a concept including bluntness of health risk perception and unhealthy behavior. The exogenous variables were composed of personal factors and socio-cultural factors. In personal factors, neuroticism, external health locus of control, blunting style of information-seeking, deficit of self-efficacy, knowledge deficit related to health, health-related experience, age and education were included. Whereas socio-cultural factors include perceived group size of unhealthy behavior and stereotypes of unhealthy behavior. Result: Personal factors and sociocultural factors were significant in explanation of the health insensitivity. Relationship between personal factors and sociocultural factors was significant, too. However, the optimistic bias as part of health insensitivity was not supported by these data. GFI, AGFI and PGFI were .95, .92, .65, respectively. Therefore, this model was verified to be a good fit to the data and parsimonious. Conclusion: Nursing to change unhealthy behavior has focused on personal factors rather than sociocultural factors. Based on this result, however, the sociocultural factors should be considered as well.

  • PDF

Size and Aspect Ratio Effects on the Magnetic Properties of a Spin-Valve Multilayer by Computer Simulation

  • Lim, S.H.;Han, S.H.;Shin, K.H.;Kim, H.J.
    • Journal of Magnetics
    • /
    • 제5권3호
    • /
    • pp.90-98
    • /
    • 2000
  • The change in the magnetic properties of a spin-valve multilayer with the structure IrMn (9 m)/CoFe (4 nm)/Cu (2.6 nm)/CoFe (2 nm)/NiEe (6 nm) is investigated as a function of the size and the aspect ratio. At a fixed aspect ratio (the length/width ratio) of 2, the magnetostatic interactions begin to affect the magnetic properties substantially at a spin-valve length of 5 $\mum$, and, at a length of 1 $\mum$, they become even more dominant. In the case of a fixed multilayer size (2.4 $\mum$) which is indicated by the sum of the length and the width, magnetization change occurs by continuous spin-reversal and M-H loops are characterized by no or very small hysteresis at aspect ratios smaller than unity, At aspect ratios greater than unity, magnetization change occurs by spin-flip resulting in squared hysteresis loops. A very large changes in the coercivity and the bias field is observed, and these results are explained by two separate contributions to the total magnetostatic interactions: the coercivity by the self-demagnetizing field and the bias field by the interlayer magnetostatic interaction field.

  • PDF

Surface Modification of WC-Co and SCM415 by the Ion Bombardment Process of Filtered Vacuum Arc Plasma (자장 여과 아크 이온빔 식각 공정을 이용한 WC-Co 및 SCM415 금속 소재 표면 구조 제어 연구)

  • Lee, Seung-Hun;Yoon, Sung-Hwan;Kim, Do-Geun;Kwon, Jung-Dae;Kim, Jong-Kuk
    • Journal of the Korean institute of surface engineering
    • /
    • 제43권2호
    • /
    • pp.80-85
    • /
    • 2010
  • The surfaces of WC-Co and SCM415 were etched to form a micro size protrusion for oil based ultra low friction applications using an ion bombardment process in a filtered vacuum arc plasma. WC-Co species showed that a self-patterned surface was available by the ion bombarding process due to the difference of sputtering yield of WC and Co. And the increasing rate of roughness was 0.6 nm/min at -600 V substrate bias voltage. The increasing rate of roughness of SCM415 species was 1.5 nm/min at -800 V, but the selfpatterning effect as shown in WC-Co was not appeared. When the SCM415 species pretreated by electrical discharge machining is etched, the increasing rate of roughness increased from 1.5 nm/min to 40 nm/min at -800 V substrate bias voltage and the uniform surface treatment was available.

The applicability study and validation of TULIP code for full energy range spectrum

  • Wenjie Chen;Xianan Du;Rong Wang;Youqi Zheng;Yongping Wang;Hongchun Wu
    • Nuclear Engineering and Technology
    • /
    • 제55권12호
    • /
    • pp.4518-4526
    • /
    • 2023
  • NECP-SARAX is a neutronics analysis code system for advanced reactor developed by Nuclear Engineering Computational Physics Laboratory of Xi'an Jiaotong University. In past few years, improvements have been implemented in TULIP code which is the cross-section generation module of NECP-SARAX, including the treatment of resonance interface, considering the self-shielding effect in non-resonance energy range, hyperfine group method and nuclear library with thermal scattering law. Previous studies show that NECP-SARAX has high performance in both fast and thermal spectrum system analysis. The accuracy of TULIP code in fast and thermal spectrum system analysis is demonstrated preliminarily. However, a systematic verification and validation is still necessary. In order to validate the applicability of TULIP code for full energy range, 147 fast spectrum critical experiment benchmarks and 170 thermal spectrum critical experiment benchmarks were selected from ICSBEP and used for analysis. The keff bias between TULIP code and reference value is less than 300 pcm for all fast spectrum benchmarks. And that bias keeps within 200 pcm for thermal spectrum benchmarks with neutron-moderating materials such as polyethylene, beryllium oxide, etc. The numerical results indicate that TULIP code has good performance for the analysis of fast and thermal spectrum system.

Effects of Cognitive Behavioral Therapy on Attention Deficit Hyperactivity Disorder among School-aged Children in Korea: A Meta-Analysis (한국 학령기 ADHD 아동을 위한 인지행동중재의 효과 연구: 메타분석)

  • Park, Wan-Ju;Park, Shin-Jeong;Hwang, Sung-Dong
    • Journal of Korean Academy of Nursing
    • /
    • 제45권2호
    • /
    • pp.169-182
    • /
    • 2015
  • Purpose: This study was a meta-analysis designed to identify effects of Cognitive Behavioral Therapy (CBT) interventions in alleviating main symptoms of Attention Deficit Hyperactivity Disorder (ADHD) among school-aged children in Korea. Methods: Examination of several databases including Research Information Sharing Service, Korean Studies Information Service System, Data Base Periodical Information Academic and hand-searched article references, resulted in identification of 1,298 studies done between 2000 and 2013 of which 21 met the inclusion criteria. Comprehensive Meta-Analysis version 2.0 was used to analyze effect sizes, explore possible causes of heterogeneity, and check publication bias with a funnel plot and its trim-and-fill analysis. Results: Overall effect size of CBT intervention was large (g=1.08) along with each outcome of self-control (g=1.26), lack of attention (g=1.02), social skills (g=0.92), and hyperactivity (g=0.92). For heterogeneity, moderator analysis was performed, but no significant differences were found between the RCT (Randomized Controlled Trials) group and the NRCT (Non RCT) group. Also, meta-regression was performed using sample size, number of sessions, and length of session as predictors, but no statistically significant moderators were found. Finally, a funnel plot along with trim-and-fill analysis was produced to check for publication bias, but no significant bias was detected. Conclusion: Based on these findings, there is clear evidence that CBT intervention has significant positive effects on the main symptoms of school-aged children suffering ADHD. Further research is needed to target diverse age groups with ADHD along with more RCT studies to improve the effectiveness of the CBT intervention.

Optical Properties of Diamond Like Carbon Films Deposited by Plasma Enhanced CVD (rf PECVD법으로 증착된 DLC film의 광학적 성질)

  • Kim, Moon-Hyup;Song, Jae-Jin;Kim, Seong-Jin
    • Korean Journal of Materials Research
    • /
    • 제11권7호
    • /
    • pp.550-555
    • /
    • 2001
  • A diamond-like carbon(DLC) films were deposited on the borosilicate glass substrate by radio frequency plasma enhanced chemical deposition(rf-PECVD). The $methane(CH_4)-hydrogen(H_2)$ gas mixture was used as precursor gas. The morphologies, the structure and the optical properties of the DLC films were investigated by SEM, Raman and UV spectrometer. The deposition rate was slightly increased with the hydrogen concentration in the gas mixture and it maintained constant at over 25 sccm of the gas flow rate. The optical band gap calculated by UV spectra decreased with increase of deposition time and DC self bias, but that were not effected by hydrogen content. Most effective parameter on the transmittance of film was bias voltage, especially in the range of ultra violet and visible light.

  • PDF

A Study on Implementation and Performance Evaluation of Wideband Receiver for the INMARSAT-B Satellite Communications System (INMARSAT-B형 위성통신용 광대역 수신단 구현 및 성능평가에 관한 연구)

  • 전중성;임종근;김동일;김기문
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • 제5권1호
    • /
    • pp.166-172
    • /
    • 2001
  • A RF wideband receiver for INMARSAT-B satellite communications system was composed of low noise amplifier and high gain amplifier, The low noise amplifier used to the resistive decoupling circuit for input impedance matching and self-bias circuits for low noise. The high gain amplifier consists of matched amplifier type to improve receiver gain. The active bias circuit can be used to provide temperature stability without requiring the large voltage drop or relatively high-dissipated power needed with a bias stabilization resistor. The bandpass filter was used to reduce a spurious level. As a result, the characteristics of the receiver implemented here show more than 60 dB in gain and less than 1.8:1 in input and output voltage standing wave ratio(VSWR), especially the carrier to noise ratio which is input signal level -126.7 dB m at 1537.5 MHz is a 45.23 dB /Hz at a 1.02 kHz.

  • PDF

Design-Based Small Area Estimation for the Korean Economically Active Population Survey (시군구 실업자 총계 추정을 위한 설계기반 간접추정법)

  • 정연수;이계오;이우일
    • The Korean Journal of Applied Statistics
    • /
    • 제16권1호
    • /
    • pp.1-14
    • /
    • 2003
  • In this study, we suggest the method of small area estimation based on the Economically Active Population Survey (EAPS) data in producing unemployment statistics for the local self-government areas (LSGAs) within large areas. The small area estimators considered are design-based indirect estimators such as the synthetic and composite estimators. The jackknife mean square error was used as a measure of accuracy of such small area estimators. The total unemployed and jackknife mean square errors of the 10 LSGAs within the large area of ChoongBuk region are derived from the estimation procedure suggested in this study, using EAPS data of December 2000. The reliability of small area estimators was assessed using the relative bias values and relative root mean square errors of these estimators. We find that under the current Korean EAPS system, the composite estimator turns out to be much more stable than other estimators.

Investigation of the Scanning Tunneling Microscopy Image, the Stacking Pattern and the Bias-voltage Dependent Structural Instability of 2,2'-Bipyridine Molecules Adsorbed on Au(111) in Terms of Electronic Structure Calculations

  • Suh, Young-Sun;Park, Sung-Soo;Kang, Jin-Hee;Hwang, Yong-Gyoo;Jung, D.;Kim, Dong-Hee;Lee, Kee-Hag;Whangbo, M.-H.
    • Bulletin of the Korean Chemical Society
    • /
    • 제29권2호
    • /
    • pp.438-444
    • /
    • 2008
  • A self-assembled monolayer of 2,2'-bipyridine (22BPY) molecules on Au(111) underwent a structural phase transition when the polarity of a bias voltage was switched in scanning tunneling microscopy (STM) experiments. The nature of two bright spots representing each 22BPY molecule on Au(111) in the high-resolution STM images was identified by calculating the partial density plots for a monolayer of 22BPY molecules adsorbed on Au(111) using tight-binding electronic structure calculations. The stacking pattern of the chains of 22BPY molecules on Au(111) was explained by examining the intermolecular interactions between the 22BPY molecules based on first principles electronic structure calculations for a 22BPY dimer, (22BPY)2. The structural instability of the 22BPY molecule arrangement caused by a change in the bias voltage switch was investigated by estimating the adsorbate-surface interaction energy using a point-charge approximation for Au(111).

Analyzing Common Method Bias of the Korean Empirical Studies on Technology Acceptance Model (한국 TAM 실증연구의 동일방법편의 분석)

  • Baek, Sang-Yong
    • The Journal of Information Systems
    • /
    • 제21권1호
    • /
    • pp.1-17
    • /
    • 2012
  • Common Method Bias(CMB) may cause the potential inflation of correlations between measures assessed via the same method. The problem of CMB has been well known in behavioral sciences because the survey method with self-reporting is vulnerable to CMB. Thus, the discussion on CMB is still ongoing in the MIS research in US. However, in Korea, the MIS research has never paid attention on the CMB problem. The purpose of this study is to examine the CMB problem in the Korean MIS research. To evaluate the effect of CMB, empirical studies on Technology Acceptance Model(TAM) are selected because (1) TAM is one of the MIS research areas studied intensively, (2) TAM is a theoretical model well supported by the existing empirical studies so that the result of this study would have a great ripple effect when the CMB problem turned out to be serious, (3) CMB is domain-specific. 47 TAM samples (out of 45 studies) from three Korean Journals were selected and the relevant data were collected such as correlation matrixes and the measures of the dependent variable. To find and evaluate the size of CMB, two analytic methods (Marker-Variable Technique and Method-Method Pair Technique) are employed. The result showed that there exists CMB in the Korean studies but the problem is not so serious to distort the empirical testing, compared with that of US studies. However, considering that CMB can contaminate the testing results, Korean MIS researchers should explicitly deal with the problem in designing empirical studies and collecting data.