• Title/Summary/Keyword: Unit bias

Search Result 161, Processing Time 0.027 seconds

Design of 60 ㎓ Millimeter-Wave Frequency Doubler using Distributed Structure

  • Park, Won;Lee, Kang-Ho;Kim, Sam-Dong;Park, Hyung-Moo;Rhee, Jin-Koo;Koo, Kyung-Heon
    • Journal of electromagnetic engineering and science
    • /
    • v.4 no.2
    • /
    • pp.87-92
    • /
    • 2004
  • A millimeter-wave distributed frequency doubler has been designed with distributed block and frequency tunable output reflectors. The simulated conversion loss of 9.5 ㏈ to 7.7 ㏈ from 54.6 ㎓ to 62.4 ㎓ output frequencies is achieved with fundamental and third harmonic signal rejections of more than 10 ㏈c. The fabricated chip has the size of 1.2 mm${\times}$1.0 mm. Some measured results of frequency and bias dependent characteristics are presented for the fabricated PHEMT MMIC frequency doubler. The designed doubler has two transistors, and if one of the transistors fails the doubler unit still operates with reduced gain. The failure effect of the PHEMT has been simulated, and compared to the measured data of which one PHEMT is not operating properly.

Gender Wage Gap in Rural Labour Markets: An Empirical Study of North East India

  • SINGH, Salam Prakash;NINGTHOUJAM, Yaiphaba
    • The Journal of Asian Finance, Economics and Business
    • /
    • v.9 no.6
    • /
    • pp.151-158
    • /
    • 2022
  • Even after three decades of economic reforms, India's labor market is characterized by stark inter-gender differences in terms of both participation rate and working time. Identification of the causes is necessary to remove the disparity and unequal sharing of economic opportunities to make way for women's empowerment. This research attempts in that direction, examining the prevalence of these inequities in rural areas of North-East Indian states using unit-level data from the 2017-18 Periodic Labour Force Survey (PLFS). The methodology for the estimation here is based on Blinder- Oaxaca decomposition method after correcting for sample bias forwarded by Heckman. The analysis shows that in both labor force participation and the wage gap, the females in the region lag behind their male counterparts by a huge margin. Further, the analysis shows that one of the main factors leading to the difference is the disparities in human capital assets. On top of female educational enrollment being low, there is also a huge lack of higher educational attainment, while males have accomplished much better in both the parameters. Moreover, the presence of social stigma against women working and discrimination put the female labor outcomes in a gloomy state.

Is fetal nuchal cord associated with autism spectrum disorder? A meta-analysis

  • Jenabi, Ensiyeh;Ahmadi, Maryam;Maleki, Azam
    • Clinical and Experimental Pediatrics
    • /
    • v.65 no.3
    • /
    • pp.131-135
    • /
    • 2022
  • Purpose: There is inconsistent evidence about the association between fetal nuchal cord and the risk of autism spectrum disorder (ASD). We performed a meta-analysis to investigate whether fetal nuchal cord is associated with an increased risk of ASD in offspring. Methods: Three main English databases were searched until January 2021. The Newcastle-Ottawa Scale was used to assess study quality. Study heterogeneity was determined using the I 2 statistic, while publication bias was assessed using Begg and Egger tests. Results are presented as odds ratios (ORs) and relative ratios with 95% confidence intervals (CI) and were determined by a random-effects model. Results: Five articles (1 cohort, 4 case-control; 3,088 total children) were included in the present meta-analysis. Fetal nuchal cord was not a risk factor for ASD (OR, 1.11; 95% CI, 0.66-1.57). There was homogeneity among studies that reported a risk of ASD (I2=0.0%). Conclusion: Our results showed that fetal nuchal cord is not a risk factor for ASD. Future large cohort studies should confirm this finding.

Design of Indoor Space Guidance System Using LiDAR and Camera on iPhone (iPhone의 LiDAR와 Camera를 이용한 실내 공간 안내를 위한 시스템 설계)

  • Junseok Jang;Kwangjae Sung
    • Journal of the Semiconductor & Display Technology
    • /
    • v.23 no.1
    • /
    • pp.71-78
    • /
    • 2024
  • In indoor environments, since global positioning system (GPS) signals can be blocked by obstacles, such as building structure. the performance of GPS-based positioning methods can be degraded because of the loss of GPS signals. To solve this problem, various localization schemes using inertial measurement unit (IMU) sensors, such as gyroscope, accelerometer, and magnetometer, have been proposed to enhance the positioning accuracy in indoor environments. IMU-based positioning methods can estimate the location of the user by calculating the velocity and heading angle of the user without the help of GPS. However, low-cost MEMS IMUs may lead to drift error and large bias. In addition, positioning errors in IMU-based positioning approaches can be caused by the irrelevant motion of the pedestrian. In this study, we propose an enhanced indoor positioning method that provides more reliable localization results by using the camera, light detection and right (LiDAR), and ARKit framework on the iPhone. Through reliable positioning results and augmented reality (AR) experiences, our indoor positioning system can provide indoor space guidance services.

  • PDF

A new cell-direct quantitative PCR based method to monitor viable genetically modified Escherichia coli

  • Yang Qin;Bo Qu;Bumkyu Lee
    • Korean Journal of Agricultural Science
    • /
    • v.49 no.4
    • /
    • pp.795-807
    • /
    • 2022
  • The development and commercialization of industrial genetically modified (GM) organisms is actively progressing worldwide, highlighting an increased need for improved safety management protocols. We sought to establish an environmental monitoring method, using real-time polymerase chain reaction (PCR) and propidium monoazide (PMA) treatment to develop a quantitative detection protocol for living GM microorganisms. We developed a duplex TaqMan quantitative PCR (qPCR) assay to simultaneously detect the selectable antibiotic gene, ampicillin (AmpR), and the single-copy Escherichia coli taxon-specific gene, D-1-deoxyxylulose 5-phosphate synthase (dxs), using a direct cell suspension culture. We identified viable engineered E. coli cells by performing qPCR on PMA-treated cells. The theoretical cell density (true copy numbers) calculated from mean quantification cycle (Cq) values of PMA-qPCR showed a bias of 7.71% from the colony-forming unit (CFU), which was within ±25% of the acceptance criteria of the European Network of GMO Laboratories (ENGL). PMA-qPCR to detect AmpR and dxs was highly sensitive and was able to detect target genes from a 10,000-fold (10-4) diluted cell suspension, with a limit of detection at 95% confidence (LOD95%) of 134 viable E. coli cells. Compared to DNA-based qPCR methods, the cell suspension direct PMA-qPCR analysis provides reliable results and is a quick and accurate method to monitor living GM E. coli cells that can potentially be released into the environment.

Role of Big Data Technology and Whistleblowing System in Distribution of Fraud Detection

  • Idrawahyuni;Gagaring PAGALUNG;Darwis SAID;Grace T. PONTOH
    • Journal of Distribution Science
    • /
    • v.22 no.9
    • /
    • pp.1-12
    • /
    • 2024
  • Purpose: The purpose of the research is to find out and analyze the direct influence of forensic audits and auditor integrity on Fraud Detection and indirect effects through big data technology and whistleblowing systems in Indonesian BPK. The research method used is a survey research method. Surveys are primary data collection methods by asking 254 individual respondents. The unit of analysis is an individual, namely the BPK RI auditors. Results of this study found a forensic audit has a positive and significant effect on fraud detection, Auditor Integrity has a positive and significant effect on Fraud Detection; and forensic Audit has a positive and significant effect on big data technology, A forensic Audit has a positive and significant effect on the whistleblowing system, Integrity auditor has a positive and significant effect on big data technology, The whistleblowing system has a positive and significant effect on fraud detection, Big data technology has a positive and significant effect on fraud detection, The whistleblowing system has a positive and significant effect on fraud detection. Similar to how we used cross-sectional data, future research is urged to use an interview-based qualitative approach to avoid typical technique bias.

Integrated calibration weighting using complex auxiliary information (통합 칼리브레이션 가중치 산출 비교연구)

  • Park, Inho;Kim, Sujin
    • The Korean Journal of Applied Statistics
    • /
    • v.34 no.3
    • /
    • pp.427-438
    • /
    • 2021
  • Two-stage sampling allows us to estimate population characteristics by both unit and cluster level together. Given a complex auxiliary information, integrated calibration weighting would better reflect the level-wise characteristics as well as multivariate characteristics between levels. This paper explored the integrated calibration weighting methods by Estevao and Särndal (2006) and Kim (2019) through a simulation study, where the efficiency of those weighting methods was compared using an artificial population data. Two weighting methods among others are shown efficient: single step calibration at the unit level with stacked individualized auxiliary information and iterative integrated calibration at each level. Under both methods, cluster calibrated weights are defined as the average of the calibrated weights of the unit(s) within cluster. Both were very good in terms of the goodness-of-fit of estimating the population totals of mutual auxiliary information between clusters and units, and showed small relative bias and relative mean square root errors for estimating the population totals of survey variables that are not included in calibration adjustments.

Comparison of Egg Testing Devices for Internal Egg Quality Measurements (계란 할란검사장비의 성능 비교)

  • Kim, Dong Jun;Jeon, Seung Yob;Kim, Hee Won;Won, Jea Sun;Lee, Jae Cheong;Lee, Kyung-Woo
    • Korean Journal of Poultry Science
    • /
    • v.43 no.4
    • /
    • pp.229-233
    • /
    • 2016
  • This study was conducted to compare three commercially available egg testing devices for measuring egg quality. The devices used were a Laser-type (automatic), a Ultrasonic-type (automatic), and a Probe-type (manual). Fresh eggs weighing 60~68 grams were obtained from a commercial hen farm. Three trials were conducted. In Trial 1, a total of 50 eggs were successively analyzed by the three egg testing devices. In Trial 2, fresh eggs were successively analyzed by a combination of two egg testing devices. In Trial 3, a total of 600 eggs (weighing 60~68 grams) laid by same flock were selected, further divided into three sub-groups with a total of 200 eggs, and analyzed by an egg testing device. In Trials 1 and 2, no apparent difference was observed in egg weight between egg testing devices. However, albumin height was scored highest in the Ultrasonic-type egg tester followed by the Probe-type and Laser-type (Trials 1 and 2). Consequently, the Haugh unit was similarly altered. Yolk color was highest in the Laser-type egg tester followed by the Ultrasonic-type and Probe-type (Trials 1 and 2). When fresh eggs laid by a single flock were independently analyzed by three devices, egg weight did not differ, but albumin height and Haugh unit were higher (p<0.05) in the Ultrasonic-type egg tester than in the Probe-type or Laser-type testers. However, Laser-type testers produced higher (p<0.05) yolk color values than the Ultrasonic-type or Probe-type egg testers. In conclusion, the commercially available egg testing devices exhibited performance differences in measuring egg qualities, which warrants further consideration as to whether the magnitude of bias and precision between the devices could be acceptable in the egg grading system, especially when assessing eggs stored for certain durations.

A Study on the Loan Structure and Profitability of Banks (은행의 대출 구조와 수익성 변동에 관한 연구)

  • Kang, Myoung-seok;Sin, Jeong-hun
    • Journal of Venture Innovation
    • /
    • v.2 no.2
    • /
    • pp.117-126
    • /
    • 2019
  • This study conducted correlation analysis and multiple regression analysis using financial statements, loan structure, ROA and ROA volatility of domestic commercial banks, regional banks and special banks for the past five years (2012 ~ 2016). The result is as follows. First, as a result of correlation analysis, bank's ROA is positively related to household loans and SME loans, but it is negatively correlated with the ratio of loans to large companies, sector bias, and loan loss provision ratio. Second, ROA volatility was negatively related to household loans and SME loans, but it was positively correlated with large corporate loans, sector bias ratio, and loan loss provision ratio. Third, as a result of the regression analysis, the variables that have a statistically significant effect on the ROA volatility of banks were household loans, SME loans, and large enterprise loans. From these empirical results, special banks with high volatility in profits need to diversify loan types and sectors in order to achieve business performance outside of policy finance. and Especially, Suhyup Bank and Nonghyup Bank, which have a large commercial role, have a large size per unit by focusing on short-term profit and Rather than focusing on large companies or large loans that are easy to obtain financial information, it is necessary to focus management capabilities on household loans and SME loans by developing capabilities such as screening techniques.

A Comparison of Observed and Simulated Brightness Temperatures from Two Radiative Transfer Models of RTTOV and CRTM (두 복사전달모델 RTTOV와 CRTM으로부터 산출된 밝기온도와 관측된 밝기온도의 비교)

  • Kim, Ju-Hye;Kang, Jeon-Ho;Lee, Sihye
    • Journal of the Korean earth science society
    • /
    • v.35 no.1
    • /
    • pp.19-28
    • /
    • 2014
  • The radiative transfer for TIROS operational vertical sounder (RTTOV) and the community radiative transfer model (CRTM) are two fast radiative transfer models (RTM) that are used as observation operators in numerical weather prediction (NWP) systems. This study compares the basic structure and input data of the two models. With data from Advanced Microwave Sounding Unit-A (AMSU-A), which has channels of various frequencies, observed brightness temperature ($T_B$) and simulated $T_B$s from the two models are compared over the ocean surface in two cases-one where cloud information is included and the other without it. Regarding AMSU-A sounding channels (5-14), the two models produce no large significant differences in their calculated $T_B$, but RTTOV produces smaller first guess (FG) departures (i.e., better results) in window and near-surface sounding channels than does CRTM. When adding cloud water and ice particles from Unified Model (UM), the $T_B$ bias between observations and simulations are reduced in both models and the bias at 31.4 and 89 GHz is substantially decreased in CRTM compared to those of RTTOV.