• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.11
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• pp.60-69
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• 1996

In this study, when the coherent detector has been developed and manufactured in the receiver of radar system, we have suggested and realized the 'Frequecny-Feedback correction (FFC)' that extracts its errors affecting the performance of radar, such as amplitude imbalances (k), phase imbalance ($\varphi$) between channels and offset votlages and corrects them to improve radar performances. Applying the FFC proposed, we analyzed sthe properties of the coherent detector and compared its perfomances after and before correction procdure. After the correction sequence, the amplitude imbalance was improved upt o 2dB and the phase imbalance over 9$^{\circ}$. The image rejection ratio (IRR), one of the figures of merit of radar system, was made better above 9 dB after correcting the coherent detector which possessed 23 dB before.

• Journal of Digital Convergence
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• v.17 no.3
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• pp.463-471
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• 2019

The purpose of this study was to investigate the effect of muscle imbalance on motion of back squat. The isokinetic muscle strength of the 8 subjects was recorded for the knee flexion/extension by the cybex 770 dynamometer. Each subject performed 3 back squats with the long barbell with an intensity of 25% body weight(BW), 50%BW, 100%BW, 125%BW. During the back squat through the recorded kinematic data the subjects' maximum flexion and extension knee angle, center of mass displacement and V-COP were calculated for evaluation of the stability of the movement. For the statistical analysis independent t-test was used. Knee flexion angle and COM displacement are dominated by the reciprocal muscle ratio. V-COP factor was dominated by bilateral extension deficit. Based on the results we can know that as the intensity of the squat increased to a level control was difficult because the muscles' imbalance influenced the movement.

• Korean Journal of Occupational Health Nursing
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• v.31 no.2
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• pp.77-85
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• 2022

Purpose: This study aimed to identify the influence of effort-reward imbalance and job satisfaction on turnover intention among hospital nurses. Methods: Data were collected from January 28 to February 10, 2022, from 237 nurses from five hospitals including clinics, general hospitals, and tertiary care hospitals located in B city. The collected data were analyzed using descriptive statistics, t-test, ANOVA, the Scheffe test, Pearson's correlation coefficients, and multiple linear regression analysis, using SPSS/WIN 26.0. Results: The average of the effort-reward ratio, an indicator of effort-reward imbalance, was 1.67±0.66, and 86.5% of the participants had a value of 1 or more. The mean job satisfaction and turnover intention were 3.32±0.48 and 3.69±0.89 on a 5-point scale, respectively. Multiple regression revealed that factors affecting turnover intention among hospital nurses included effort-reward imbalance (β=.30, p<.001) and job satisfaction (β=-.32, p<.001), and these variables explained 29.0% of turnover intention. Conclusion: These findings indicate that effort-reward imbalance and job satisfaction are associated with turnover intention. Therefore, to decrease the turnover intention of hospital nurses, interventions and policies should be prepared to resolve the nurse's effort-reward imbalance and increase job satisfaction at regional or national level hospitals.

• Journal of the Korean Geographical Society
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• v.49 no.3
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• pp.390-404
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• 2014

This study analysed the job-housing balance using the number of employees and workers data, and investigated the relationship between job-housing ratio and commuting trip in the Seoul metropolitan area. Between 2005-2010, in the central business district which functioned as urban center, the number of employees were reduced and population growth slowed. Meanwhile, the suburbanization of employment and population has advanced as the employment and population moved from Seoul to Gyeonggi-do. As the increasement of workers compared to the employees became prominent, the excess workers increased significantly. The size of excess workers acted as a factor which reduced the job-housing ratio. Job-housing imbalance worsened in Gyeonggi-do especially. While in many regions, job-housing imbalance improved in clerical, sales, and professional job sectors, but in some regions, the job-housing imbalance worsened in simple labor job and service job sectors. The number of jobs which job-housing imbalance was eased increased in the employment center. The more the job-housing ratio is high, the lower the degree of self-sufficiency of commuting trip and the proportion of internal commuters. In business centers where the number of employees exceed the number of workers, the job-housing ratio and the proportion of commuting trips coming from other regions showed decreasing trend together. The results bear important implications for regional labour market plans considering the spatial mismatch between jobs and housing.

• Journal of Korean Society on Water Environment
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• v.34 no.1
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• pp.77-83
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• 2018

This paper aims to evaluate the results of toxicity testing with Daphnia magna and Vibrio fischeri on wastewater samples which might be influenced by ion imbalance. The effluents from factories were found to be more toxic with high salinity levels than those from public wastewater treatment plant (WTP) and sewage treatment plant (SWP). Clion composition was highest in the effluent, in terms of percentage, which was followed by $Na^+$, $SO_4^{2-}$ and $Ca^{2+}$. $K^+$ and $Mg^{2+}$ ion was relatively low. The sensitivity of D. magna test results was higher than V. fischeri. Among samples which were proved by V. fischeri testing to be nontoxic, the composition ratio of each ion whether toxic samples or nontoxic samples which were decided by D. magna toxicity testing, were compared. $Na^+$, $K^+$, $Ca^{2+}$, $Mg^{2+}$ ion composition ratio showed high level in nontoxic samples whereas $SO_4^{2-}$ and $Cl^-$ ion composition ratio was high in toxic samples. Accordingly, $SO_4^{2-}$ and $Cl^-$ ion seemed to be considered the ions causing toxicity in effluent. Toxicity from some categories of industries (Mining of non-metallic minerals, Manufacture of basic organic petrochemicals, Manufacture of other basic organic chemicals, Manufacture of other chemical products etc.) seemed to be influenced by salinity. The Ion concentration in influent and effluent were similar. Concentration of $Na^+$, $Cl^-$, $K^+$, $Ca^{2+}$ ions were high in influent, however $Mg^{2+}$ and $SO_4^{2-}$ ions were high in effluent.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.2 no.1
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• pp.69-75
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• 2007

Objectives : This study was performed to find the correlation between moire topography and muscle development ratio of both lower limbs. Methods : 88-general persons who examed general health checkup were enrolled this study. Who coincided the exclusion criteria were left out. The authors practiced Moire Topography by using IBS-2000 and measured difference of contour line and interval between vertical base line of neck and pelvis. We made use of X-SCAN to analyse body component and calculate muscle development ratio of both lower limbs. Results : In this study, we found out that the more interval between vertical base line of neck and pelvis grown large, the more muscle development ratio of both lower limbs got small. So, there was correlation between imbalance of the dorsum muscle and muscle development ratio of both lower limbs.(p>0.05). But others did not have. Conclusion : According to this results, we found out there was correlation between imbalance of lumbar and gluteal region and muscle development ratio of both lower limbs. Apply to clinic, we are able to improve the efficacy of diagnosis and medical treatment.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.9
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• pp.735-738
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• 2018

The accuracy of extracting the azimuth angle of a target is significantly affected by the error in the mono-pulse ratio of the air-borne antenna hybrid mono-pulse Radar system. This error is strongly induced by the phase imbalance between the channels of the system. In this paper, a method is proposed for effectively calibrating the phase imbalance caused by physical differences between the RF channels from the antenna to the $180^{\circ}$ hybrid. Through a flight test, it was confirmed that the accuracy of the azimuth angle of the target is improved by using the proposed method.

• Korea journal of population studies
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• v.20 no.1
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• pp.65-96
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• 1997

The main purpose of this study is to explore the determinants of sex ratio imbalance at birth in Taegu which has experienced the extremely imbalanced sex ratio at birth since mid-1980s. This paper attempts to compare the determinants of sex ratio imbalance at birth, such as sex discrimination against women, son preference, prenatal sex identification followes by sex-selective induced abortions, among married women aged 25 to 44 in Taegu with those in Bay area, California in USA. The research is based on the survey data which were conducted in Taegu, Repulic of Korea and Bay area, California in USA. The findings of this analysis suggest that married women in Taegu are more likely to feel sex discrimination against women than married women in Bay area. Furthermore, the percentage of married women's effort for son bearing before pregnancy is much higher than that of married women in Bay area. We also have found that the percentage of sex-selective induced abortion in Taegu is six times higher than that of married women in Bay area. According to the logistic regression analysis, the determinants of sex-selective induced abortion among married women in Taegu are discrimination against women, son preference, prenatal sex identification. On the other hand, age is the only variable which has an important impact on sex-selective induced abortion among married women in Bay area. From the findings of this study, we can conclude that son preference based on Cofucianism is the most important impact on sex ratio imbalance at birth in Taegu where son preference is much stronger than other regions in Korea. The phenomenon of extremely imbalanced sex ratio at birth in Taegu is the result of combination of these factors, such as strong son preference, seeking to have at least one son within small family size, and prenatal sex identification followed by sex-selective induced abortion.

• Journal of Haehwa Medicine
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• v.18 no.2
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• pp.13-20
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• 2009

Objectives : In order to investigate change of isokinetic trunk muscle strength according to decrease of body composition analysis parameter after obesity treatment. Methods : 2 obese patients have been treated with oriental medical obese treatment for 1 month. One patient got the exercise treatment, another didn't. Before and after treatment, the segmental bioelectrical impedance analysis, isokinetic trunk muscle strength test were performed. Then we analyzed the relationship of data. Results : After obesity treatment, BMI(Body Mass Index), PBF(Percentage of Body Fat), WHR(Waist Hip Ratio) were decreased in all patient and LBM(Lean Body Mass) was increased. In non-exercise patient, Ext.PT(extension Peak Torque) was decreased and Flex.PT(flexion Peak Torque) was increased. In exercise patient showed the opposite results. E/F ratio became more imbalance. Conclusions: Ext.PT was decreased in non-exercise patient but increased in exercise patient. And the trunk muscle strength became imbalance in both patients, right after the treatment. So trunk muscle exercise should be carried out and it is necessary to do long term study.

• Journal of Korean Physical Therapy Science
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• v.23 no.1
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• pp.24-32
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• 2016

Purpose: Muscle imbalance around the knee region, especially quadriceps imbalance, is considered one of the main contributing factors to the development and progression of knee dysfunction based on the changes observed via electromyography (EMG). This study aimed to investigate the effect of vastus lateralis (VL) inhibition taping using non-elastic tape on the EMG activity of the vastus medialis oblique (VMO) and VL during isometric knee extension. Method: Thirty-three healthy young adults (11 males and 22 females) were recruited. With and without VL inhibition taping, the participants performed isometric knee extension in the sitting position for a total of 7 seconds. Result: VMO/VL EMG ratio significantly increased after VL inhibition taping (p<.05). Conclusion: These findings suggest that VL inhibition taping may contribute to VL inhibition and may help improve VMO/VL ratio in young adults. We expect VL inhibition taping to be useful in individuals with greater VL than VMO activity