• Journal of fish pathology
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• v.21 no.2
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• pp.107-117
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• 2008

The pharmacokinetic properties of oxytetracycline (OTC) were studied after dipping and oral administration to cultured olive flounder, Paralichthys olivaceus (600 g). Plasma concentrations of OTC were determined after oral dosage (50, 100 and 200 mg/kg body weight) and dipping (50, 100 and 200 ppm, 1 h) in olive flounder (average 600 g, 23±1℃). Plasma samples were taken at 3, 5, 10, 15, 24, 32, 48, 72, 120, 168 and 240 h post-dose. In oral dosage of 50, 100 and 200 mg/kg, the peak plasma concentrations of OTC, which attained at 3 h post-dose, were 0.34, 0.44 and 1.18 ㎍/㎖, respectively. In dipping of 50, 100 and 200 ppm, those of OTC which also observed at 5 h post-dose, were 0.43, 0.38 and 0.64 ㎍/㎖, respectively. Plasma concentrations of OTC were not measurable at 240 h post-dose in all experiments. The kinetic profile of absorption, distribution and elimination of OTC in plasma were analyzed fitting to a one-compartment model by WinNonlin program. The following parameters were calculated for a single dosage of 50, 100 and 200 mg/kg body weight, respectively: AUC (the area under the concentration-time curve)=31.40, 28.07 and 32.97 ㎍∙h/㎖; T1/2 (half-life)􀆫0.89, 1.12 and 0.43 h; Tmax (time for maximum concentration)= 5.25, 3.70 and 7.30 h, Cmax (maximum concentration)=0.25, 0.38 and 0.61 ㎕/㎖. Following dipping at 50, 100 and 200 ppm, these parameters were AUC􀆫15.51, 14.63 and 19.72 ㎍∙h/㎖; T1/2= 0.75, 0.41 and 0.74 h; Tmax=4.90, 7.08 and 4.68 h, Cmax=0.40, 0.32 and 0.46 ㎕/㎖.

• Bulletin of the Society of Naval Architects of Korea
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• v.11 no.1
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• pp.27-34
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• 1974

This study is aimed at a validation of the vigilance simulation model which was proposed earlier (2). The model estimates a perceived danger value, an alertness level and the probability of detection at a given elapsed time of vigilance. Twenty-nine male and seven female subjects were given a simple task. They were asked to detect a number(four numbers out of six digits in the telephone directory which have the probability of occurrence in the range of 0.0010-0.0018) in six different experimental conditions, for periods of two to three hours. Analysis of the experiments showed that although the mean detection rate varied slightly in two hours, the within-subject variance and the number of cyclic performance fluctuations increased significantly. A primal factor that affects the performance seems to be the frequency of target occurrence. By curve fitting, the relation between the probability of detection and the percentages of danger event occurrence was derived; $y=0.50(1-{\varepsilon}^{-50x^2})+0.39$. Assuming the equation represents the normal detection rate(100% performance), the Relative Vigilance Performance Rating was calculated. This rating method could be a useful criterion in selecting and training of the vigilance personnel. The results show that the simulation model is a good estimator of human a performance when the probability of danger occurrence is greater than 0.0015; it gives a good reference for improving the vigilance system. Suggestions are made that (1) the validity of proposed functional equations over the extended range of danger probability be studied, (2) an analysis of the cyclic fluctuations of the alertness level be accomplished, and (3) the cost functions of detection reliability be included in any future model.

• Genomics & Informatics
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• v.19 no.1
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• pp.11.1-11.8
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• 2021

For the novel coronavirus disease 2019 (COVID-19), predictive modeling, in the literature, uses broadly susceptible exposed infected recoverd (SEIR)/SIR, agent-based, curve-fitting models. Governments and legislative bodies rely on insights from prediction models to suggest new policies and to assess the effectiveness of enforced policies. Therefore, access to accurate outbreak prediction models is essential to obtain insights into the likely spread and consequences of infectious diseases. The objective of this study is to predict the future COVID-19 situation of Korea. Here, we employed 5 models for this analysis; SEIR, local linear regression (LLR), negative binomial (NB) regression, segment Poisson, deep-learning based long short-term memory models (LSTM) and tree based gradient boosting machine (GBM). After prediction, model performance comparison was evelauated using relative mean squared errors (RMSE) for two sets of train (January 20, 2020-December 31, 2020 and January 20, 2020-January 31, 2021) and testing data (January 1, 2021-February 28, 2021 and February 1, 2021-February 28, 2021) . Except for segmented Poisson model, the other models predicted a decline in the daily confirmed cases in the country for the coming future. RMSE values' comparison showed that LLR, GBM, SEIR, NB, and LSTM respectively, performed well in the forecasting of the pandemic situation of the country. A good understanding of the epidemic dynamics would greatly enhance the control and prevention of COVID-19 and other infectious diseases. Therefore, with increasing daily confirmed cases since this year, these results could help in the pandemic response by informing decisions about planning, resource allocation, and decision concerning social distancing policies.

• Structural Engineering and Mechanics
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• v.69 no.6
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• pp.627-635
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• 2019

In order to study the axial compression performance of sand-lightweight concrete-filled steel tube (SLCFST) stub columns, three circular SLCFST (C-SLCFST) stub column specimens and three SLCFST square (S-SLCFST) stub column specimens were fabricated and static monotonic axial compression performance testing was carried out, using the volume ratio between river sand and ceramic sand in sand-lightweight concrete (SLC) as a varying parameter. The stress process and failure mode of the specimens were observed, stress-strain curves were obtained and analysed for the specimens, and the ultimate bearing capacity of SLCFST stub column specimens was calculated based on unified strength theory, limit equilibrium theory and superposition theory. The results show that the outer steel tubes of SLCFST stub columns buckled outward, core SLC was crushed, and the damage to the upper parts of the S-SLCFST stub columns was more serious than for C-SLCFST stub columns. Three stages can be identified in the stress-strain curves of SLCFST stub columns: an elastic stage, an elastic-plastic stage and a plastic stage. It is suggested that AIJ-1997, CECS 159:2004 or AIJ-1997, based on superposition theory, can be used to design the ultimate bearing capacity under axial compression for C-SLCFST and S-SLCFST stub columns; for varying replacement ratios of natural river sand, the calculated stress-strain curves for SLCFST stub columns under axial compression show good fitting to the test measure curves.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.172-175
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• 2016

Time of Flight(ToF) LiDAR(Light Detection And Ranging) technology has been used for distance measurement and object detection by measuring ToF time information. This technology has been evolved into higher precision measurement field such like autonomous driving car and terrain analysis since the retrieval of exact ToF time information is of prime importance. In this paper, as a accuracy indicator of the ToF time information, timing jitter was measured and analyzed through Single-Shot LiDAR system(SSLs) mainly consisting of 1.5um wavelength MOPA LASER, InGaAs Avalanche Photodiode(APD) at 31M free space environment. Additionally, we applied spline interpolation and multiple-shot averaging method on measured data through SSLs to improve ToF timing information.

• Journal of the Korea Fashion and Costume Design Association
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• v.23 no.1
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• pp.113-127
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• 2021

This study aims to analyze the style of men's suits and extract expressional words for the development of semantic differential scales of visual images according to the change in silhouette. Research methods are literature studies, case studies, and questionnaires. The stimuli were created using CLO 3D, a virtual sewing CAD. This study's results are as follows: 1) The British suit jacket has an angled shoulder line using thin pads, and a slightly higher waistline. The pants of the suit have a high waistline and two pleats, so the thighs of the pants are wide. The American suit jacket has a natural shoulder line, and the waistline is not emphasized. The width of the jacket is relaxed, and the length is long. The pants of the suit have a higher waistline, and the pants are wide as well. The Italian suit jacket has wide shoulders, and the waistline is connected lower with a soft curve, and the length is relatively short. The trousers of the suit are tapered and get narrower as it goes down to the hem. 2) Because it originated in the practices of true bespoke tailoring, traditional British suits have a far more 'fitted' silhouette than the mass-produced styles that became emblematic of the American style. By the late 1950s, a sack-style suit was standard American business attire. This technique gives the sack suit its characteristically 'boxy' silhouette. The "Continental" presented a highly tailored silhouette, with padded shoulders, a slim, tight-fitting chest, and a closely tapered waist. The story was that Italian culture valued aesthetics over all else and thus sought the 'slim' suit style as much as possible. 3) The main expressional words of visual images for men's suits differ greatly depending on the silhouette of suit. The visual images are ranked in the order of 'neat', 'classic', 'educated', 'hard', 'mature', for fitted silhouettes. The words of 'masculine', 'basic', 'comfortable', 'simple', 'mature', 'conservative', 'modern', are ranked for boxy silhouettes. And the words of 'slim', 'young', 'neat', are noted for slim silhouettes.

• Korean Journal of Optics and Photonics
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• v.33 no.6
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• pp.317-323
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• 2022

In this investigation, we describe a chromatic confocal sensor based on a geometric phase lens for measuring the thicknesses of transparent plates. In order to design a compact sensor, a geometric phase lens, which has diffractive and polarizing characteristics, is used as a device to generate chromatic aberration, and a fiber optic module is adopted. The systematic error of the sensor is reduced with wavelength peak detection by Gaussian curve fitting and the common error compensation obtained by the repeatedly consecutive experimental results. An approach to calculate the plate thickness is derived and verified with sapphire and BK7 plates. Because of the simple and compact design of the proposed sensor with rapid measurement capability, it is expected to be widely used in thickness measurements of transparent plates as an alternative to traditional approaches.

• Journal of the Institute of Convergence Signal Processing
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• v.22 no.2
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• pp.51-56
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• 2021

The brachial systolic blood pressure and pulse pressure are the predictors of cardiovascular disease in individuals over 50 years of age. As the stiffness increases, the reflex amplitude and pressure in the late systole increase, resulting in an increase in left ventricular load and myocardial oxygen demand. Therefore, it is necessary to study how stiffness affects blood pressure. In this study, the blood pressure pulse waves were measured before and after taking the drug, and the blood pressure pulse wave was measured before and after myocardial heart transplantation in patients with heart failure. The correlation between R, L, and C components of the Windkessel model was estimated by increasing blood pressure. As a result of modeling the parameters of the Windkessel model using the curve fitting method, the increase in blood pressure and decrease in systolic rise time were due to the increase in the L component in the RLC Windkessel model. Among the various mechanical characteristics of blood vessels, the most important parameter affecting high BP waveform is the inertance.

• Animal Bioscience
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• v.34 no.4
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• pp.770-782
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• 2021

Objective: The aim of the present study was to compare the effectiveness of three approaches (the seasonal auto-regressive integrated moving average [SARIMA] model, the nonlinear autoregressive exogenous [NARX] artificial neural networks and Wood's model) to the prediction of milk yield during lactation. Methods: The dataset comprised monthly test-day records from 965 Polish Holstein-Friesian Black-and-White primiparous cows. The milk yields from cows in their first lactation (from 5 to 305 days in milk) were used. Each lactation was divided into ten lactation stages of approximately 30 days. Two age groups and four calving seasons were distinguished. The records collected between 2009 and 2015 were used for model fitting and those from 2016 for the verification of predictive performance. Results: No significant differences between the predicted and the real values were found. The predictions generated by SARIMA were slightly more accurate, although they did not differ significantly from those produced by the NARX and Wood's models. SARIMA had a slightly better performance, especially in the initial periods, whereas the NARX and Wood's models in the later ones. Conclusion: The use of SARIMA was more time-consuming than that of NARX and Wood's model. The application of the SARIMA, NARX and Wood's models (after their implementation in a user-friendly software) may allow farmers to estimate milk yield of cows that begin production for the first time.

• Journal of Advanced Navigation Technology
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• v.24 no.6
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• pp.573-580
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• 2020

In this paper, the characteristics of the inductor and capacitor, which are the basic components of the circuit, are constructed in a form that can be used in the LTCC multilayer. The inductors and capacitors used for the analysis were designed with rectangular spiral structures and MIM structures inside dielectrics with a dielectric constant of 7, respectively. The measured results were extracted from each element of the equivalent circuit proposed by the curve fitting method and verified the validity of the proposed equivalent circuit based on the extracted results. The analyzed inductor and capacitor were implemented in the form of library and proved its usefulness by applying to Elliptical type 5th LPF design. The LPF was measured through practical production, and as a result, the insertion loss in the passband DC ~ 3.7 GHz was up to 1.0 dB, the return loss was 19.2 dB, and the attenuation in the rejection band was 23.9 dB, which was close to the design goal.