• Annals of Clinical Neurophysiology
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• 제19권2호
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• pp.131-135
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• 2017

Background: Neuromuscular ultrasound can be used to assess the diaphragm. Before it can be used clinically, the reference ranges of diaphragm thickness and contractility must be determined. Methods: We measured the thickness of the diaphragm and the diaphragmatic thickening fraction (DTF) in 80 healthy volunteers with ultrasound and collected their demographic information to determine if age, sex, and body mass index (BMI) influence these measures. Results: The thickness of the diaphragm at resting end expiration was $0.193{\pm}0.044cm$ on the right side and $0.187{\pm}0.039cm$ on the left. The DTF was $104.8{\pm}50.6%$ on the right side and $114.9{\pm}49.2%$ on the left. Sex, weight, height, and BMI significantly affected the thickness of the diaphragm, but had little effect on the DTF. Conclusions: Normal reference values for the diaphragm should be helpful when evaluating the diaphragm. The DTF appears more useful than resting diaphragm thickness because it is affected less by individual variation.

• Clinical and Experimental Pediatrics
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• 제57권1호
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• pp.35-40
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• 2014

Purpose: Height-specific blood pressure (BP) is the standard parameter used to diagnose childhood hypertension. However, there has been some argument that weight may be a better variable than height in the reference BP standards. Therefore, before assessing the BP status using the reference BP standards, a basic understanding of the fundamental association of weight and height with BP is required. Methods: In the present study, we analyzed the correlation of BP with height and weight in Korean adolescents (age, 10-19 years), using data from the Korean National Health and Nutrition Examination Surveys (2009-2011). Results: Systolic BP (SBP) was more closely correlated with weight than with height in the normal weight (body mass index [BMI], ${\leq}85th$ percentile) and overweight (BMI, >85th percentile) groups and in the normal waist circumference (WC, ${\leq}90th$ percentile) and high WC (>90th percentile) groups in both sexes. Diastolic BP (DBP) had a higher correlation with height than with weight in the normal weight and normal WC groups, whereas weight was more closely associated with DBP than height in the overweight and high WC groups in both boys and girls. Conclusion: In Korean adolescents, weight had a greater effect on SBP than height in both the normal weight and overweight groups. DBP was mainly affected by height in the normal weight group, whereas weight was the major determinant of DBP in the overweight group. Therefore, it may be necessary to consider weight in the establishment of reference BP standards.

• 제어로봇시스템학회논문지
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• 제22권6호
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• pp.453-462
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• 2016

This paper proposes a torque control method for surface mounted permanent magnetic synchronous motor (PMSM) driven by a 2-level voltage source driven inverter, which has fast torque response and small torque ripple. The proposed torque control method follows the finite control set model predictive control (FCS-MPC) strategy. A reference state is derived at each time step for the given time varying torque reference and the cost index is defined so that the tracking error for this reference state should be penalized. The choice of an optimal output voltage vector is made first from the 6 possible active voltage vectors of the 2-level voltage source inverter. Then a modulation factor for the chosen optimal voltage vector is obtained so that the torque ripple can be reduced further. It is shown that the proposed FCS-MPC control method yields fast torque tracking response and small torque ripple through simulation and experiments.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권5호
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• pp.2529-2543
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• 2019

Scanning electron microscopy (SEM) image can link with the microscopic world through reflecting interaction between electrons and materials. The SEM images are easily subject to blurring distortions during the imaging process. Inspired by the fact that dark channel prior captures the changes to blurred SEM images caused by the blur process, we propose a method to evaluate the SEM images sharpness based on the dark channel prior. A SEM image database is first established with mean opinion score collected as ground truth. For the quality assessment of the SEM image, the dark channel map is generated. Since blurring is typically characterized by the spread of edge, edge of dark channel map is extracted. Then noise is removed by an edge-preserving filter. Finally, the maximum gradient and the average gradient of image are combined to generate the final sharpness score. The experimental results on the SEM blurred image database show that the proposed algorithm outperforms both the existing state-of-the-art image sharpness metrics and the general-purpose no-reference quality metrics.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.194-197
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• 2007

This paper proposes a linearization technique for the 3 level NPC type inverter, which increases the linear control range of inverter up to the 6-step inverter. The overmodulation range is divided into two modes depending on the modulation index(MI), In mode I, the reference angles are derived from the Fourier series expansion of the reference voltage corresponds to the MI. In mode II, the holding angles are also derived in the same way. Therefore, it is possible to obtain the linear control and the maximized utilization of PWM inverter output voltage.

• Earthquakes and Structures
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• 제9권4호
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• pp.851-873
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• 2015

A methodology for estimation of statistical properties (viz. mean and standard deviation) of the expected seismic damage to reinforced concrete framed structures subject to corrosion of reinforcement, over a specified reference time (typically the service life of the structure) is proposed in this paper. The damage to the structure under the earthquake loading is characterised by the damage index, determined using the modified Park and Ang damage model. The reduction in area, yield strength and strain at ultimate of steel reinforcement, and the reduction in compressive strength of cover concrete due to corrosion are taken into account in the estimation of damage. The proposed methodology is illustrated through an example problem. From the results obtained, it is noted that there is an increase of about 70% in the mean value of expected seismic damage to the reinforced concrete frame considered over a reference time of 30 years when effect of corrosion is taken into consideration. This indicates that there is a need to consider the effect of corrosion of reinforcement on the estimation of expected seismic damage.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 추계학술대회 논문집
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• pp.666-669
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• 2000

Localization is the process of aligning the robot's local coordinates with the global coordinates of a map. A mobile robot's location is basically computed by a dead reckoning scheme, but this position information becomes increasingly inaccurate during navigation due to odometry errors. In this paper, the method of building a map of a robot's environment using ultrasonic sensor data and the occupancy grid map scheme is briefly presented. Then, the search and matching algorithms to compensate for the odometry error by comparing the local map with the reference map are proposed and verified by experiments. It is shown that the compensated error is not accumulated and exists within the limited range.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 추계학술대회 논문집
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• pp.439-443
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• 1996

A fuzzy teaming controller is experimentally designed to control the ball k beam system in this paper. Although most fuzzy controllers have been built just to emulate human decision-making behavior, it is necessary to construct the rule bases by using a learning method with self-improvement when it is difficult or impossible to get them only by expert's experience. The algorithm introduces a reference model to generate a desired output and minimizes a performance index function based on the error and error-rate using the gradient-decent method. In our balancing experiment of the ball ＆ beam system, this paper shows that the fuzzy control rules by learning are superior to the expert's experience.

• The Korean Journal of Ecology
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• 제15권1호
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• pp.1-7
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• 1992

The dvelopment of leaves in soybean(glycine max cv. yellow grain and glycine max cv. black grain)plant were assessed for the applicability of the plastochron index. The plastochron ages versus time in days were respectively 6.4 days in black grain and 9.6 days in yellow grain. Plots of plastochron indes(pi) versus time were linear, there were two distinct groups of regression line. when a point of intersection in the lines were upper than the reference length, pi was estimated n+(ln Ln-ln LR)/(ln Ln-ln Ln+2) or (n-1)+(ln Ln-1-ln LR)/(ln Ln-1-ln Ln+1) . When a point of intersection in the lines were less than the reference length, pl was estimated n+(ln Ln-ln LR)/(ln Ln-ln Ln+2) or (n-1)+(ln Ln-1-ln LR)/(ln Ln-1-ln Ln+1) . The growth rate of black grain plants analysed by pl was higher than yellow grain plants.

• 한국임상수의학회지
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• 제38권2호
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• pp.69-74
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• 2021

This study investigated hematological index from clinically healthy Korean Domestic Shorthair (KDSH) cats and characterized breed-specific hematological features. Blood samples from clinically healthy and FIV/FeLV-negative KDSH cats were used in this study (n = 34). After hematological analysis, reference intervals (RIs) of KDSH cats were established and compared with published feline RIs. Most of the RIs were similar to published RIs, however, the RI of MCV tends to be lower than the published RIs and the RIs of Hgb, MCH, MCHC, and CHCM were higher than the published RIs. This study suggests that breed-specific RIs, especially MCV, Hgb, MCH, MCHC, and CHCM, may be required for KDSH cats rather than applying the published RIs.