• Journal of the Korean Graphic Arts Communication Society
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• v.26 no.2
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• pp.31-43
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• 2008

The functional dyes, which has various optical characteristics that can be applicable to field of electronic, photo electronic, such as sensor or electrode, were synthesized. Physical property and optical stability was studied with preparation of conductive type film as a kind of optical filter of plasma display panel, by adapting neon cut off dye, which can selectively absorbing between 580 and 610nm wavelength. The filter was prepared with PSA resin, which has functional group of - COOH and - OH, as binder. And the characters such as spectroscopy, heat-proof / wet-proof, thermal stability and commerciality, which must be held by functional dyes, were examined. Conductive type film is the kind of film includes only neon cut off dyes. For the neon cut off dyes, cyanine dyes can be applied. And it is observed that spectrum of before and after the durability test are not changed due to stability of dyes, as the result of coating on the mesh film with PSA binder.

• Journal of Korean Critical Care Nursing
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• v.12 no.2
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• pp.26-38
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• 2019

Purpose : The aims of this study were to identify the incidence of pressure ulcers and to compare the predictive validities of pressure ulcer risk assessment scales among trauma patients. Methods : This was a prospective observational study. A total of 155 patients admitted to a trauma intensive care unit in a university hospital were enrolled. The predictive validity of the Braden, Cubbin & Jackson, and Waterlow scales were assessed based on the sensitivity, specificity, positive and negative predictive values, and area under the receiver operating characteristic curve (AUC). Results : Of the patients, 14 (9.0%) subsequently developed pressure ulcers. The sensitivity, specificity, positive predictive values, and negative predictive values were 78.6%, 75.9%, 24.4%, and 97.3%, respectively, for the Braden scale (cut-off point of 12); 85.7%, 68.8%, 21.4%, and 98.0%, respectively, for the Cubbin & Jackson scale (cut-off point of 26); and 71.4%, 87.2%, 35.7%, and 96.9%, respectively, for the Waterlow scale (cut-off point of 18). The AUCs were 0.88 (Waterlow), 0.86 (Braden), and 0.85 (Cubbin & Jackson). Conclusion : The findings indicate that the predictive validity values of the Waterlow, Braden, and Cubbin & Jackson scales were similarly high. However, further studies need to also consider clinical usefulness of the scales.

• Journal of radiological science and technology
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• v.42 no.5
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• pp.345-350
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• 2019

Liver biopsy is the gold standard for diagnosing liver fibrosis, but it is invasive and has a risk for complications. For this reason, recently, study has been actively conducted on non-invasive liver fibrosis evaluation method. But, there is no established standard for the type of diffuse liver disease. Therefore, this study was suggest the usefulness and cut-off values of Fibroscan, FIB-4, APRI and AAR of patients with hepatitis C in Korea. According to the diagnosis, 240 people in hepatitis C are classified into fatty liver, chronic hepatitis, and liver cirrhosis. The statistical analysis was performed by ANOVA to verify difference between groups. The ROC curve was analyzed to determine the usefulness and practical cut-off value. As a result, for all diseases, the AUC value for Fibroscan was 0.8 over and the APRI was 0.7 over. Cut-off value of serum based liver fibrosis markers was increased in order of fatty liver, chronic hepatitis and liver cirrhosis. If Fibroscan and serological liver fibrosis markers are applied to predict liver fibrosis, it is expected that excessive liver biopsy can be reduced.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.12
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• pp.42-48
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• 2020

Given the increasing interest in air pollution, several technologies to measure black carbon (BC) aerosol particles have been developed. As most BC aerosol particles are smaller than 1 ㎛, it is necessary to pre-separate the particles by size before a BC measuring instrument samples the aerosol particles. In this study, a miniature cyclone separator for portable BC measuring instruments was developed. A numerical approach was used to design the miniature cyclone separator with operating flow rates of 50, 100, or 150 mLPM, and then a prototype cyclone separator was manufactured for experimental validation. The numerical results of the cut-off size and pressure drop of the miniature cyclone separator agreed well with the experimental data. The cut-off sizes of the miniature cyclone separator were determined to be 2.9, 0.94, and 0.63 ㎛ for operating flow rates of 50, 100, and 150 mLPM, respectively. Thus, the miniature cyclone separator is suitable for use as a sampling inlet for the portable black carbon measuring instrument to sample BC aerosol or PM2.5 aerosol.

• Structural Engineering and Mechanics
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• v.77 no.5
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• pp.571-586
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• 2021

The present paper studies the influence of the inhomogeneous initial stresses in the bi-layered hollow cylinder and it is assumed that these stresses are caused by the hydrostatic pressures acting on the interior and outer free surfaces of the cylinder. The study is made by utilizing the version of the three-dimensional linearized theory of elastic waves in bodies with initial stresses for which the initial stress-strain state in bodies is determined within the scope of the classical linear theory of elasticity. For the solution to the corresponding eigenvalue problem, the discrete-analytical method is employed. Numerical results are presented and analyzed for concrete selected pairs of materials. According to these results and their analyses, it is established that, unlike homogeneous initial stresses, the influence of the inhomogeneous initial stresses on the torsional wave dispersion has not only quantitative but also qualitative character. For instance, in particular, it is established that as a result of the initial stresses caused by the hydrostatic pressure acting in the interior free surface of the cylinder, the cut-off frequency appears for the fundamental dispersive mode and the values of this frequency increase with the intensity of this pressure.

• The Journal of the Convergence on Culture Technology
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• v.10 no.3
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• pp.145-154
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• 2024

In order to operate predictive models utilizing administrative big data, it is crucial to consider policy changes and the characteristics of highly volatile data. Considering this scenario, this study proposes the Cut-off Voting Classifier (CVC) algorithm. This proposed algorithm prevents a sharp decline in accuracy by utilizing multiple weak classifiers. The study validates the proposed algorithm's performance through experiments. The performance evaluation demonstrates the ability to maintain stable prediction rates even in situations with a sharp decline in predictive model accuracy.

• The Korean Journal of Community Living Science
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• v.25 no.2
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• pp.261-269
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• 2014

This study evaluates the nutritional retention factors influencing beef based on different cuts and boiling. Two cuts (brisket and shin foreshank) were prepared from beef and used in this experiment. Boiling methods were applied to each cut. The fat content of the boiled shin foreshank cut (236.43%) exceeded that of the brisket cut (142.38%). The moisture content of the boiled brisket cut (47.68%) was lower than that of the shin foreshank cut (49.54%). The sodium content of the boiled shin foreshank cut (47.89%) exceeded that of the brisket cut (37.30%). The potassium content of the boiled brisket cut (41.90%) exceeded that of the shin foreshank cut (39.63%). The calcium content of the boiled brisket cut (48.43%) was lower than that off the shin foreshank cut (71.34%). The phosphorus content of the boiled brisket cut (58.09%) exceeded that of the shin foreshank cut (57.24%). The iron content of the boiled brisket cut (72.72%) was lower than that of the shin foreshank cut (87.29%). Nutritional retention factors represent output data on cooking methods with a yield (%) for each item.

• Nuclear Engineering and Technology
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• v.55 no.9
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• pp.3291-3300
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• 2023

Recently molybdenum alloys have been introduced as accident tolerating materials for cladding of fuel rods. Molybdenum element has seven stable isotopes with different neutron absorption cross section used in various fields, including nuclear physics and radioisotope production. This study presents separation approaches for all intermediate isotopes of molybdenum element by squared-off cascades using a newly developed numerical code with Salp Swarm Algorithm (SSA) optimization algorithm. The parameters of cascade including feed flow rate, feed entry stage, cascade cut, input feed flow rate to gas centrifuges (GCs), and cut of the first stage are optimized to maximize both isotope recovery and cascade capacity. The squared off and squared cascades are studied, and the efficiencies are compared. The results obtained from the optimization showed that for the selected squared off cascade, Mo⁹⁴ in four separation steps, Mo⁹⁵ in five steps, Mo⁹⁶ in six steps, Mo⁹⁷ in seven steps, and Mo⁹⁸ in two steps are separated to the desired concentrations. The highest recovery factor is obtained 63% for Mo⁹⁴ separation and lowest recovery factor is found 45% for Mo⁹⁵.

• Applied Chemistry for Engineering
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• v.30 no.4
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• pp.504-508
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• 2019

The feasibility of replacing the tope cell of pn GaInP homojunction with our GaInP/AlGaInP heterojunction structure in III-V semiconductor multijunction photovoltaic (MJPV) cells having the highest current conversion efficiency was investigated. The performance of photovoltaic (PV) cells grown on $2^{\circ}$ and $10^{\circ}$ off-oriented GaAs substrates were compared to each other. The PV cells on the $10^{\circ}$ off-cut substrate showed higher short-circuit current density ($J_{sc}$) and conversion efficiency values than that of using the $2^{\circ}$ one. For $2{\times}2mm^2$ area PV cell on $10^{\circ}$ off substrate, the $J_{sc}$ of $9.21mA/cm^2$ and the open-circuit voltage of 1.38 V were measured under 1 sun illumination. For $5{\times}5mm^2$ cell on $10^{\circ}$ off substrate, the conversion efficiency was decreased from 6.03% (1 sun) to 5.28% (20 sun) due to a decrease in fiill factor (FF).

• Journal of Korea Water Resources Association
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• v.39 no.6 s.167
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• pp.479-486
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• 2006

In this study, 2-D seepage analysis is conducted for the evaluation of Box-Culvert installation, Cut-off Wall Length, permeability reduction of soil under the Box-Culvert effects on Levee Box-Culvert safety. The result of analysis it is obtained that the safety of seepage and slope stability of levee is declined by the installation of Box-Culver. And also obtained that the piping from poor compaction and cavity around Box-Culvert Is Prevented by the Cut-off wall installation below breast wall and levee toe, so it is recommended that the Cut-off Wall below breast wall and levee toe must be installed. And the Cut-off Wall installed below levee center is considered when the safety of piping is declined for the whole levee section. On the other hand, for the realistic analysis it is recommended that the 3-D seepage analysis is more suitable for the safety evaluation of Box-Culvert installed levee when it is considered that the saturated field is dispersed to the ground.