• Title/Summary/Keyword: Mass bias

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The Polarization of Public Opinion and the Influential Factors on the Polarization between Pusan and Gwangju (지역과 세대 간 여론양극화와 그 영향요인에 관한 연구: 부산과 광주 지역을 대상으로)

  • Park, Sun-Hee;Han, Hye-Kyoung
    • Korean journal of communication and information
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    • v.39
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    • pp.178-223
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    • 2007
  • The polarization of public opinion by regionalism is one of biggest problems in Korean society. This study attempts to examine the polarization of public opinion between two typical cities representing regionalism and explore the factors influencing on the polarization. The results show that the polarization of public opinion is based on the perceived public opinion rather than the real public opinion. The polarization of public opinion is greater with regional issue than national issue. In general, citizens of Pusan have a conservative bias in estimating other Pusan citizens' opinion and a liberal bias in estimating Gwangju citizens' opinion, whereas citizens of Gwangju have a looking-glass perception in estimating other Gwangju citizens' opinion and a conservative bias in estimating Pusan citizens' opinion. There are no significant differences of the real public opinion and the perceived opinion across three generations. But within each generation, the tendency of public opinion polarization is found between regions and is not shown to change over generations. Regression analyses show that individual's opinion and region are highly predictable variables that explain the perceived public opinion and the perception bias such as false consensus and pluralistic ignorance.

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Improving Stability and Characteristic of Circuit and Structure with the Ceramic Process Variable of Dualband Antenna Switch Module (Dual band Antenna Switch Module의 LTCC 공정변수에 따른 안정성 및 특성 개선에 관한 연구)

  • Lee Joong-Keun;Yoo Joshua;Yoo Myung-Jae;Lee Woo-Sung
    • Journal of the Microelectronics and Packaging Society
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    • v.12 no.2 s.35
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    • pp.105-109
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    • 2005
  • A compact antenna switch module for GSM/DCS dual band applications based on multilayer low temperature co-fired ceramic (LTCC) substrate is presented. Its size is $4.5{\times}3.2{\times}0.8 mm^3$ and insertion loss is lower than 1.0 dB at Rx mode and 1.2 dB at Tx mode. To verify the stability of the developed module to the process window, each block that is diplexer, LPF's and bias circuit is measured by probing method in the variation with the thickness of ceramic layer and the correlation between each block is quantified by calculating the VSWR In the mean while, two types of bias circuits -lumped and distributed - are compared. The measurement of each block and the calculation of VSWR give good information on the behavior of full module. The reaction of diplexer to the thickness is similar to those of LPF's and bias circuit, which means good relative matching and low value of VSWR, so total insertion loss is maintained in quite wide range of the thickness of ceramic layer at both band. And lumped type bias circuit has smaller insertion itself and better correspondence with other circuit than distributed stripline structure. Evaluated ceramic module adopting lumped type bias circuit has low insertion loss and wider stability region of thickness over than 6um and this can be suitable for the mass production. Stability characterization by probing method can be applied widely to the development of ceramic modules with embedded passives in them.

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Ordinary Press Consumers' Predisposed Attitude's and Fairness Judgment (언론소비자가 갖는 이슈에 대한 태도가 언론의 공정성 판단에 미치는 영향)

  • Ahn, Cha-Su
    • Korean journal of communication and information
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    • v.46
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    • pp.323-353
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    • 2009
  • Press (un)fairness has been a social issue in Korea. The previous research focused mainly on the suggestion of fairness norms, principles, concepts, and definitions. Also, the research tried to measure the degree of fairness by analyzing press contents. This study attempted to overcome the media- and source-oriented approach proposing ordinary press consumers' perspectives. The study posited that one's fairness judgment would be greatly influenced by his or her preexisting attitudes on issue. Based on social judgment theory and hostile media perception framework, the research expected 'assimilation' bias for attitudinally congruent group and 'contrast' bias for attitudinally incongruent group. An $3\times3\times2$ experimental design was employed to test the theoretical predictions. The results found assimilation and contrast bias for strong attitude groups who read one-sided and two-sided messages. The results also implied hostile media perception occurred by selective categorization. Also the difficulty and limitation of traditional fairness judgment and media-centered approach was discussed.

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Development and validation of prediction equations for the assessment of muscle or fat mass using anthropometric measurements, serum creatinine level, and lifestyle factors among Korean adults

  • Lee, Gyeongsil;Chang, Jooyoung;Hwang, Seung-sik;Son, Joung Sik;Park, Sang Min
    • Nutrition Research and Practice
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    • v.15 no.1
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    • pp.95-105
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    • 2021
  • BACKGROUND/OBJECTIVES: The measurement of body composition, including muscle and fat mass, remains challenging in large epidemiological studies due to time constraint and cost when using accurate modalities. Therefore, this study aimed to develop and validate prediction equations according to sex to measure lean body mass (LBM), appendicular skeletal muscle mass (ASM), and body fat mass (BFM) using anthropometric measurement, serum creatinine level, and lifestyle factors as independent variables and dual-energy X-ray absorptiometry as the reference method. SUBJECTS/METHODS: A sample of the Korean general adult population (men: 7,599; women: 10,009) from the Korean National Health and Nutrition Examination Survey 2008-2011 was included in this study. The participants were divided into the derivation and validation groups via a random number generator (with a ratio of 70:30). The prediction equations were developed using a series of multivariable linear regressions and validated using the Bland-Altman plot and intraclass correlation coefficient (ICC). RESULTS: The initial and practical equations that included age, height, weight, and waist circumference had a different predictive ability for LBM (men: R2 = 0.85, standard error of estimate [SEE] = 2.7 kg; women: R2 = 0.78, SEE = 2.2 kg), ASM (men: R2 = 0.81, SEE = 1.6 kg; women: R2 = 0.71, SEE = 1.2 kg), and BFM (men: R2 = 0.74, SEE = 2.7 kg; women: R2 = 0.83, SEE = 2.2 kg) according to sex. Compared with the first prediction equation, the addition of other factors, including serum creatinine level, physical activity, smoking status, and alcohol use, resulted in an R2 that is higher by 0.01 and SEE that is lower by 0.1. CONCLUSIONS: All equations had low bias, moderate agreement based on the Bland-Altman plot, and high ICC, and this result showed that these equations can be further applied to other epidemiologic studies.

Electrospray-Mass Spectrometric Analysis of Plasma Pyrophosphates Separated on a Multi-Modal Liquid Chromatographic Column

  • Lee, Su-Hyeon;Lee, Jeong-Ae;Lee, Won-Yong;Chung, Bong-Chul;Choi, Man-Ho
    • Mass Spectrometry Letters
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    • v.2 no.4
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    • pp.92-95
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    • 2011
  • Pyrophosphates are the key intermediates in the biosynthesis of isoprenoids, and their concentrations could reveal the benefits of statins in cardiovascular diseases. Quantitative analysis of five pyrophosphates, including isopentenyl pyrophosphate (IPP), dimethylallyl pyrophosphate (DMAPP), geranyl pyrophosphate (GPP), farnesyl pyrophosphate (FPP), and geranylgeranyl pyrophosphate (GGPP), was performed using liquid chromatography-tandem mass spectrometry (LC-MS/MS) in negative ionization mode. After dilution with methanol, samples were separated on a 3 ${\mu}m$ particle multi-modal $C_{18}$ column ($50{\times}2$ mm) and quantified within 10 min. The gradient elution consists of 10 mM ammonium bicarbonate and 0.5% triethylamine (TEA) in water and 0.1% TEA in 80% acetonitrile was used at the flow rate of 0.4 mL/min. Overall recoveries were 51.4-106.6%, while the limit of quantification was 0.05 ${\mu}g$/mL for GPP and FPP and 0.1 ${\mu}g$/mL for IPP, DMAPP, and GGPP. The precision (% CV) and accuracy (% bias) of the assay were 1.9-12.3% and 89.6-111.8%, respectively, in 0.05-10 ${\mu}g$/mL calibration ranges ($R^2$ > 0.993). The devised LC-MS/MS technique with the multi-modal $C_{18}$ column can be used to estimate the biological activity of pyrophosphates in plasma and may be applicable to cardiovascular events with cholesterol metabolism as well as the drug efficacy of statins.

A Study on Improving Mass Production of the Radar Sensor Oscillator (레이더 센서용 발진기의 양산성 향상에 관한 연구)

  • Kim, Byung-Chul;Cho, Kyung-Rae;Lee, Jae-Buom;Kim, Dae-Hyung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.4
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    • pp.669-676
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    • 2012
  • In this paper, The method to improve the mass production method of the radar sensor is suggested by using the temperature compensation circuit which is composed with the thermister. The mass production became easier by decreasing the adjustment time for the exact oscillation frequency with the temperature compensation circuit that can support the proper gate bias voltage for the FET after the dielectric resonator is removed from the DRO(Dielectric Resonator Oscillator) of the radar sensor. Radar sensor with the proposed method has 15.67MHz oscillator frequency variation in the temperature range of $-20^{\circ}C-+55^{\circ}C$, 0.65dB magnitude variation, -105.47dBc phase noise characteristics at 1MHz which are better or similar temperature characteristics with the DRO whose oscillator frequency variation is 25MHz, magnitude variation is 0.42dB and phase noise is -107.40dBc in the same temperature range.

Simultaneous Quantification of Oleins (triolein, diolein and monoolein) in Mouse Feces using Liquid Chromatography-Electrospray Ionization/Mass Spectrometry

  • Lim, Jong-Hyun;Lee, Jeong-Ae;Jang, Yu-Ra;Chung, He-Sson;Lee, Won-Yong;Chung, Bong-Chul
    • Mass Spectrometry Letters
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    • v.3 no.3
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    • pp.68-73
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    • 2012
  • Fat malabsorption is an important cause of poor growth in infancy and childhood. Steatorrhea tests have been developed using various methods. Traditional measurements of stool fat, however, require large samples and it often takes as a week to complete the analysis. In this paper, a liquid chromatography-electrospray ionization/mass spectrometry (LC-ESI/MS) method was developed for simultaneous quantitative analysis of triacylglycerols, triolein, diolein and monoolein, in mouse feces. Moreover, the procedure was rapid, simple as well as compatible with LC-ESI/MS. Chloroform-isopropyl alcohol solution was used for fat-soluble sample extraction. After centrifugation and filtration, an analytical solution was prepared. Triolein, diolein and monoolein were separated using non-aqueous reversed-phase column with the mobile phase consisting of A (methanol) and B (acetone-isopropyl alcohol). The precision (% CV) and accuracy (% bias) of the assay were 3.8-14.7% and 85.2-114.9%, respectively. This method has been successfully applied to simultaneous determination of triolein, diolein and monoolein in feces from 30 mice. This method can therefore be applied to measure triacylglycerols in mouse feces accurately and precisely by LC-ESI/MS, thereby helping to predictive biomarker in fat malabsorption and diagnostic research.

Media Criticism on TV for the Last 10 Years: A Content Analysis of (TV 미디어 비평의 어제와 오늘: <미디어비평(KBS)> 10년, 내용분석)

  • Hong, Won-Sik;Kim, Eun-Jung
    • Korean journal of communication and information
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    • v.64
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    • pp.59-84
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    • 2013
  • It has been 10 years since KBS first broadcasted TV program for the purpose of expanding mutual criticism among Korean mass media. This study conducted a content analysis of KBS episodes for the last 10 years. Through the content analysis, this study explored what the program had showed us in the aspects of 'the subject of criticism', 'the ground of criticism', 'the attribution of criticism'. The content analysis could show meaningful results to the study of media criticism, because it not only provides a meta-analysis of the problems Korean mass media have had for the last 10 years but also examines the program has been consistent in the regard of criticism fairness. The result of this study showed that has pointed out the practices of unfairness, political bias and superficial and shallow reporting as the most critical problems the Korean mass media have. Also, the result showed that had not been consistent in the regards of 'the subject of criticism', 'the ground of criticism', 'the attribution of criticism'. While the program mostly focused on the problems of political bias and unfairness in the early stage, the focus of criticism moved to the problems of sensationalism and superficial reporting laster. This study discussed that the change of criticism might have a relation with the change of KBS governance.

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An Evaluation of the Accuracy of Mini-Wright Peak Flowmeters in Patients with Asthma and Chronic Obstructive Pulmonary Disease (천식 및 만성폐쇄성폐질환 환자에서 Mini-Wright Peak Flowmeter로 측정한 최대호기유속의 정확도)

  • Choi, Won-Il;Han, Seung-Beom;Jeon, Young-June
    • Tuberculosis and Respiratory Diseases
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    • v.50 no.3
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    • pp.310-319
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    • 2001
  • Background : The peak flowmeter is very useful in monitoring of out-patients as well as those in emergency departments because of its convenience and simplicity with low cost. There have been many studies aimed at determining the accuracy and reproducibility of the peak flow meter in normal population. However, there is a paucity of reports regarding its accuracy in patients with chronic obstructive pulmonary disease(COPD) or asthma. The accuracy of the peak expiratory flow(PEF) measured with a mini-Wright peak flowmeter was assessed by a comparison with the results of a mass flow sensor. Methods : The PEF measurements were performed in 108 patients aged 19-82 years presenting with either a chronic obstructive lung disease or asthma before and after inhaling salbutamol. The PEF measurements from the mini-Wright flowmeter were compared with those obtained by the calibrated mass flow sensor. Results : The average of the readings taken by the mini-Wright meter were 37-39 l/min higher than those taken by the mass flow sensor. The average percentage error of the mini-Wright meter were higher, ranging less than 300 l/min. The mean of the differences between the values obtained using both instruments (the bias)$\pm$limits of agreement(${\pm}2$ SD) were $37.1{\pm}90\;l/min$ for the PEF(p<0.001). Conclusions : The mini-Wright peak flowmeter overestimated the flows in patients with COPD or asthma. It was also found that the accuracy of the mini-Wright peak flowmeter decreased in its mid to low range. The limits of agreement are wide and the difference between the two instruments is significant. Therefore, the measurements made between the two types of machines in patients with asthma or COPD cannot be used interchangeably.

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Measurement of Cortisol in Human Serum by Isotope Dilution Liquid Chromatography/Mass Spectrometry and a Comparison through a Proficiency Testing

  • Lee, Hwa-Shim;Shin, Hye-Sun;Park, Sang-Ryoul;Park, Chang-Joon
    • Bulletin of the Korean Chemical Society
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    • v.31 no.5
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    • pp.1149-1154
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    • 2010
  • Liquid chromatography/mass spectrometry using isotope dilution method has been established as a primary method for the measurement of cortisol in human serum. Verification of this method was accomplished by the participation in Consultative Committee for Amount of Substance-Metrology in Chemistry (CCQM) pilot study. Two levels of cortisol certified reference materials were prepared and certified by the established method. They were used as sample materials for the proficiency testing. The expanded uncertainty in the measurement of cortisol in human serum was approximately 1.2% at 95% confidence level. The results of the proficiency testing showed a good precision among the participants, but some bias to the certified values. This means that commercial field laboratories should keep traceability chain to SI unit through available reference measurement procedures and/or available reference materials.