• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.737-740
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• 2003

In this study, the influence of cement factor on the early strength gain and the other properties of concrete is discussed. According to the result, the setting time is faster in order of alumina cement(AC), high-early-strength cement(HSC) and ordinary Portland cement(OPC), and when OPC are replaced with HSC and AC, the final setting time is faster than when only OPC is used. At 10% replacement of AC, the instant setting happens. As the particle of cement is minute, setting time is shortened. As the properties of hardened concrete, the time when compressive strength of 5㎫, which the form can be removed, is gained is about 18 and 16 hours in the case of OPC and HSC respectively, and in the case of AC, it is about 5 hours. It also shows 16 hours at the replacing ratio of HSC of 50%, and 26 and 72 hours at the replacing ratio of AC of 5 and 10% respectively. And it shows 21, 16 and 12 hours with variation of fineness of cement, so early strength gain is fast with an increase of fineness. The coefficient of correlation between compressive strength and the rebound value is over 0.97, is very favorable. Therefore, if the rebound value of P type Schmidt hammer is more than 25, it is thought that the side forms can be removed.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.6
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• pp.641-646
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• 2014

In this paper, we propose a controller for a ball and beam system which reduces the measurement error effect under AC and DC noise. The ball and beam system measures data through a sensor. If sensor noise is included in a controller via the feedback channel, the signal is distorted and the entire system cannot work normally. Therefore, some appropriate action for the measurement error effect is essential in the controller design. Our controller is equipped with a gain-scaling factor and a compensator to reduce the effect of measurement error in the feedback signal. Effectively, our proposed controller can reduce the AC and DC noise of a feedback sensor. We analyze the proposed controller by Laplace transform technique and illustrate the improved control performance via an experiment for a ball and beam system.

• Toxicological Research
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• v.30 no.4
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• pp.297-304
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• 2014

Peppermint (Mentha piperita) is a plant native to Europe and has been widely used as a carminative and gastric stimulant worldwide. This plant also has been used in cosmetic formulations as a fragrance component and skin conditioning agent. This study investigated the effect of peppermint oil on hair growth in C57BL/6 mice. The animals were randomized into 4 groups based on different topical applications: saline (SA), jojoba oil (JO), 3% minoxidil (MXD), and 3% peppermint oil (PEO). The hair growth effects of the 4-week topical applications were evaluated in terms of hair growth, histological analysis, enzymatic activity of alkaline phosphatase (ALP), and gene expression of insulin-like growth factor-1 (IGF-1), known bio-markers for the enhanced hair growth. Of the 4 experimental groups, PEO group showed the most prominent hair growth effects; a significant increase in dermal thickness, follicle number, and follicle depth. ALP activity and IGF-1 expression also significantly increased in PEO group. Body weight gain and food efficiency were not significantly different between groups. These results suggest that PEO induces a rapid anagen stage and could be used for a practical agent for hair growth without change of body weight gain and food efficiency.

• Fisheries and Aquatic Sciences
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• v.24 no.9
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• pp.311-317
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• 2021

Inclusion effect of various levels of jack mackerel meal (JMM) acting as feed attractants and/or stimulants in diets on the growth, feed consumption, feed utilization and whole body composition of rockfish was investigated. Three hundred juvenile rockfish were randomly allocated into 15 flow-through tanks. Five experimental diets supplemented with JMM at 0%, 1%, 3%, 5%, and 10% at the expense of anchovy meal were prepared and referred to as the JMM0, JMM1, JMM3, JMM5, and JMM10 diets, respectively. Weight gain, specific growth rate (SGR) and feed consumption of fish tended to improve with dietary levels of JMM. The greatest weight gain, SGR and feed consumption were observed in fish fed the JMM10 diet, followed by the JMM5, JMM3, JMM1, and JMM0 diets, in that order. Condition factor (CF) of fish tended to improve with dietary inclusion levels of JMM. Growth performance, feed consumption and CF of fish tended to improve with dietary inclusion levels of JMM ranging from 0% to 10%.

• Journal of the Korea Society of Computer and Information
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• v.15 no.5
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• pp.13-21
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• 2010

The Optimal results of Kalman Filtering on the Inverted Pendulum System requires an effective factor such as the noise covariance matrix Q, the measurement noise covariance matrix R and the initial error covariance matrix $P_0$. We present a special case where the optimality of the filter is not destroyed and not sensitive to scaling of these covariance matrix because these factors are unknown or are known only approximately in the practical situation. Moreover, the error covariance matrices issued by this method predict errors in the state estimate consistent with the scaled covariance matrices and not the issued state estimates. Various results using the scalar gain $\delta$ are derived to described the relations among the three covariance matrices, Kalman Gain and the error covariance matrices. This paper is described as follows: Section III a brief overview of the Inverted Pendulum system. Section IV deals with the mathematical dynamic model of the system used for the computer simulation. Section V presents a various simulation results using the scalar gain.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.9
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• pp.657-662
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• 2022

In this paper, the calculation using simulation and two measurement methods for G/T of the telemetry are analyzed. Antenna gain and noise temperature are calculated by using ICARA and Antenna Noise Temperature Calculator. System G/T were calculated by using Antenna gain/noise temperature, LNA gain/noise temperature, cable loss. The first G/T measurement method is Y-factor measurement method, which is to calculate G/T by comparing LNA noise temperature and a signal level difference when an antenna and a 50ohm termination are respectively connected to an LNA input terminal Second method is Solar calibration measurement method that is to calculate G/T by comparing noise level difference when looking at the sun and lowest level point. Finally, the accuracy was reviewed by comparing the G/T calculation results with the two measurement methods, and the optimal measurement method according to antenna performance and operating environment was presented.

• Journal of Korean Biological Nursing Science
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• v.22 no.2
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• pp.119-126
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• 2020

Purpose:Weight gain after kidney transplantation is a critical factor that can lead to poor outcomes with cardiovascular complications. Many studies have been conducted to identify predictive markers of future weight changes at the time of transplant. Recently, circulating exosomes and its contents including miRNAs and proteins have attracted attention as potential biomarkers. In this pilot study, we investigated exosomal proteins and weight change after kidney transplant. Methods: Recipients (n = 10) were classified into two groups; weight gainers (n = 5, 9.7 ± 4.4kg) and weight losers (n = 5, -6.4 ± 1.8kg) based on their weight changes at 12-months posttransplant. Based on the exosomal protein profiles obtained by the LC-MS/MS, differentially expressed proteins were identified between the groups. Results: Concentration and the mean size of exosomes significantly increased at 12-months compared to the baseline (p= .009) in the total group. Eleven exosomal proteins were found at the baseline as differentially expressed between the two groups. In the weight gain group, complement proteins including HV169, C3, C4B, and C4A, were significantly upregulated. Conclusion: Our pilot study suggests that exosomal complementary proteins are associated with weight gain after kidney transplantation. Further studies are needed to clarify the role of these exosomal proteins in the underlying mechanisms of weight changes in kidney transplant recipients.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.10 no.5
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• pp.786-795
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• 1999

To detect the precise of arrival of target signal in real ocean environments, Inverse beamformnig(IBF) solutions to the Inverse beamforming integral equation are surveyed theoretically and the performance properties of the IBF are analyzed with simulations. IBF-Cardioid beamforming algorithm is proposed for port/starboard discrimination and the performance gains are studied with simulations. It is shown that IBF has a 3 dB array noise gain advantage over CBF under ideal conditions. This 3 dB array noise gain advantage is proven by theocratical studies and simulations. This array noise gain advantage leads to a minimum detectable level advantage for IBF output compared with CBF output. The fact that the IBF beamwidth is narrower than the CBF beamwidth by a factor of 0.68 proves the performance of detection and spatial resolution improvement. Comparing the simulation results of IBF-Cardioid beamforming and Conventional Cardioid beamforming, it is shown that IBF-Cardioid beamformer have performance enhancement in minimum detection level, detection accuracy and resolution.

• The Journal of the Acoustical Society of Korea
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• v.34 no.5
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• pp.403-409
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• 2015

In this paper, we propose Packet Loss Concealment (PLC) method using adaptive signal scale estimation for performance improvement of G.711 PLC. The conventional method controls a gain using 20 % attenuation factor when continuous loss occurs. However, this method lead to deterioration because that don't consider the change of signal. So, we propose gain control by adaptive signal scale estimation through before and after frame information using Least Mean Square (LMS) predictor. Performance evaluation of proposed algorithm is presented through Perceptual Evaluation of Speech Quality (PESQ) evaulation.

• Journal of Biosystems Engineering
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• v.21 no.4
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• pp.436-448
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• 1996

An earth tube soil air heat exchange system was designed, installed and operated as a single pass heat exchanger to utilize the geothermal energy as an natural energy source. This study was undertaken to investigate the potential of the heating and cooling, energy gain, heat exchange efficiency and coefficient of performance of the system. The system consisted of 30m in length and 30cm in diameter polyethylene pipes buried 2m deep in soil. Maximum heating and cooling performance were 2.51㎾ and 1.26㎾ at the air mass rate of 21cmm. Energy gain and coefficient of performance were the function of temperature difference between outside air and soil temperature. They were expressed as Q=0.33$ imes$$Delta T_{max}$+0.134(㎾) for energy gain and COP=0.44$ imes$$Delta T_{max}$+0.178 for coefficient of performance with correlation factor of 0.95. The mean of heat exchange efficiencies was 85.6%.