• Composites Research
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• v.31 no.2
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• pp.51-56
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• 2018

A new study was carried out to utilize a pencil drawing paper sensor (PDPS), which drew a line using a pencil on the paper, as a sensor. The sensing effect on 3 different papers based on the properties of PDPS was compared. The specimens were prepared by drawing 4B pencils on plain (A4), Hwasun, and Han papers. The silver paste was used to give good electrical contacts of the copper wires and the pencil drawn line. The chemical structures of 3 papers for PDPS by FT-IR spectrum analysis were similar and the comparative compact states of each paper were observed by optical microscope. From statistical evaluation of tensile strength using 3 papers, plain paper was chosen to be best for the PDPD. The optimum drawing number of PDPD was determined by changing the thickness of the paper with the drawing number. Electrical resistance (ER) with graphite on 3 different papers were compared. The changes in compression was observed through cyclic compressive test of composite materials, it was possible to predict the degree of strain sensing under compressive test. It leads to expectation of properties.

• Korean Journal of Agricultural Science
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• v.43 no.4
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• pp.612-622
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• 2016

The purpose of this study was to evaluate the effects of sex, birth year, birth season, and parity of sows on their progeny using the following on-farm test records: Backfat Thickness (BF), Fresh Meat Percent (FMP), Loin depth (LD), Age at 90kg (90D), and Average Daily Gain (ADG). Statistical analysis was performed using data collected from 1,178 Yorkshire and 13,395 Landrace progenies, which were born from 119 Yorkshire and 1,191 Landrace sows, respectively between 2011 and 2015. All results of the analysis were statistically significant (P < 0.05) except the birth season effect on LD. For Landrace, the highest ratings were found to be at the $5^{th}$ parity (BF), at the $3^{rd}$ parity (FMP and LD), at the $2^{nd}$ parity (90D and ADG). For Yorkshire, the highest ratings were at the $2^{nd}$ parity (BF and FMP), at the $3^{rd}$ parity (LD), and at the $4^{th}$ parity (90D and ADG). Although the ratings of carcass traits of progeny appear to be higher between the maternal sow's $2^{nd}$ and $4^{th}$ progenitor, no significant relations to parity were found. Based on these results, we concluded that maternal parity is not significantly affect carcass traits of progeny and thus that the best slaughtering age of sows should not be determined solely based on maternal parity but also in consideration of other factors such as unit costs of production. The results of this study would provide fundamental information to future studies on the effect of economical parity on sows and swine breeding.

• Journal of Korean Ophthalmic Optics Society
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• v.15 no.3
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• pp.287-291
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• 2010

Purpose: The aim of this study was to compare binocular functions such as near point of convergence (NPC), AC/A ratios, heterophoria, accommodation, accommodation lag, positive relative accommodation (PRA), negative relative accommodation (NRA), positive relative convergence (PRC), negative relative convergence (NRC) in normal subjects and convergence insufficiency. Methods: 86 subject (male n=45, female n=41, mean $age{\pm}SD=23.27{\pm}2.85$ years) without amblyopia, strabismus, and ocular pathology were studied. Forty three patients each group were classified as normal subjects and convergence insufficiency group based on AC/A ratio and far and near phoria. Binocular function of the two groups was measured using phoropter. r. Results: The values between normal subjects and convergence insufficiency were 5.71 cm and 7.07 cm for NPC, 5.28 and 2.81 for Heterophria AC/A, 0.92 exo/3.36 exo and 2.17 exo/10.84 exo for far and near phoria, 15.49/23.30/13.30 and 13.50/20.02/9.09 for PRC, respectively. However, there were no significant differences between normal subjects and convergence insufficiency for accommodative amplitude, accommodative lag, PRA, NRA, BI vergence test, BO vergence test, NRC. Conclusions: Both groups were a significant difference for cover test, NPC, Heterophria AC/A, far and near phoria, break point of PRC, and recovery point of PRC.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.167-170
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• 2005

We performed field test and analyzed results of field test in variable HFC(Hybrid Fiber Coaxial) network environments. And we investigated whether the test results is satisfied in DOCSIS(Data-over-Cable Service Interface Specification) 2.0 and OpenCable standard. Also, we propose HFC improvement problem for HFC Network quality as BcN(Broadband convergence Network) access network. We tested three sample areas. The sample areas represent various type of SO(System Operator) in korea. The field test was to measure signal level about digital channels. In results of multiple digital channels, in case of "Equalizer ON", we could be obtained very good test results. The results of field test were shown in satisfying recommended values in DOCSIS 2.0 and OpenCable. So, we could have confidence through field test that BcN will be possible to be adapted to environment of korea HFC network.

• Journal of the Korean Society of Industry Convergence
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• v.24 no.3
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• pp.315-321
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• 2021

In this study, the natural frequency analysis of the fuel pipe and vibration test jig was performed as a basic study to determine the vibration characteristics of the vehicle's fuel pipe and the stability analysis of fatigue failure of the pipe. The natural frequencies of the fuel pipe and the fuel pipe with the test jig were calculated and the results were compared. As a result of the analysis, it was found that the natural frequency of the fuel pipe and the natural frequency of the test jig differed about 7 times, so that the vibration of the test jig did not affect the vibration of the fuel pipe. In addition, as a result of the natural frequency analysis of the fuel pipe itself and the pipe with the test jig attached, the maximum error is less than about 1%. In the future, it was suggested that the analysis of the design changed fuel pipe may be performed without a test jig.

• Journal of the Korea Convergence Society
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• v.7 no.4
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• pp.51-58
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• 2016

The purpose of this study was to examine the effects of clinical convergence self-directedness practice learning program on self-directedness and competency in fundamental nursing skills in undergraduate nursing students. The study design was a non-equivalent pre-post quasi-experimental design. The participants were 80 nursing students in D city. The experimental and control groups were randomly assigned with 40 participants in each group. Interventions for the experimental group were visiting clinical practice, video recording and students' self-debriefing of what they did over the 5 days. Self-directedness and competency in fundamental nursing skills were measured 2 times (pre-, and post-intervention) over the 5 days. Independent t-test, Mann-Whitney U test and chi-square test were used for data analyses. There was statistically significant difference for self-directedness(t=12.93, p=.001) and competency in fundamental nursing skills(t=8.34, p=.021). Results indicate that self-debriefing method using video recording is an effective learning way to improve Self-directedness and competency in fundamental nursing skills in nursing students.

• East Asian Economic Review
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• v.20 no.1
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• pp.37-65
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• 2016

This research intends to investigate the progress made in East Asian bond market integration thus far. Price-based measures (AAD indicator and beta-convergence measure), quantity-based measures and econometric techniques (co-integration test, error correction model based Granger causality test) are employed in the analysis. Even though East Asian government bond markets have become more integrated since 2001, the differentials among the markets still remain significantly high. The bond market integration process seems slow. The convergence of bond markets sped up in 2003 and after the 2008 world financial crisis, implying the important role of government policies in integrating the regional bond markets. East Asian bond market integration may need more government-directed measures.

• Journal of Convergence for Information Technology
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• v.11 no.10
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• pp.68-73
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• 2021

This study was to identify the effects of using Gratitude Diary Writing on self-esteem and internal-external locus of control to adolescent. A randomized controlled experimental design was used. There were 20 participants in the experimental group, and 19 in the control group. Data were analyzed using Chi-square test, Fisher's exact test, t-test. The results of self-esteem(t=5.142, p=<.001) and internal-external locus of control(t=5.821 p=<.001)l showed statistically significant differences between the two groups. Using thank journal writing is effective in improving adolescents self-esteem and internal-external locus of control. If the gratitude diary writing effect of gratitude is verified by selecting a wide sample, it is expected that it will be helpful for generalize activities.

• Composites Research
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• v.31 no.6
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• pp.392-397
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• 2018

In this study, the development purpose is to replace steel Tie Rod of commercial vehicle to the carbon composite by a braiding process. CFRP tie rod was designed to meet the performance requirements of existing products by designing the cross section of the core for braiding weaving and the structural design of the joint between the core and the carbon fiber. The specimens were fabricated by braiding method and applied to structural analysis through test evaluation. The manufacturing process proceeded from braiding to infusion through post-curing process. The test evaluation of the final product was satisfactorily carried out by sequentially performing tensile test, torsion test, compression test and fatigue test. In addition, the weight of CFRP tie rod could be reduced by about 37% compared to existing products.

• Proceedings of the Korean Statistical Society Conference
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• 2003.05a
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• pp.191-197
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• 2003

This paper considers the independence test for two stationary infinite order autoregressive processes. For a test, we follow the empirical process method devised by Hoeffding (1948) and Blum, Kiefer and Rosenblatt (1961), and construct the Cram${\acute{e}}$r-von Mises type test statistics based on the least squares residuals. It is shown that the proposed test statistics behave asymptotically the same as those based on true errors.