• Journal of the Korea Organic Resources Recycling Association
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• v.29 no.2
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• pp.31-38
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• 2021

The aim of this study is to evaluate the possibility of treating slaughterhouse by-products using microbial electrolysis cells (MECs). The diluted pig liver was fed to MEC reactors with the influent COD concentrations of 772, 1,222, and 1,431 mg/L, and the applied voltage were 0.3, 0.6, and 0.9 V. The highest methane production of 5.9 mL was obtained at the influent COD concentration of 1,431 mg/L and applied voltage of 0.9 V. In all tested conditions, COD removal rate was increased as the influent COD concentration increased with average removal rate of 62.3~81.1%. The maximum methane yield of 129~229 mL/g COD was obtained, which is approximately 80% of theoretical maximum value. It might be due to the bioelectrochemical reaction greatly increased the biodegradability of pig liver. Future research is required to improve the methane yield and digestibility through optimizing the reactor design and operating conditions.

• Journal of Digital Convergence
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• v.10 no.1
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• pp.1-10
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• 2012

In this paper, we review recently emerging smart applications, and analyzed policy implications in light of digital convergence perspective. While extant literatures on smart applications mainly dealt with consumer behaviors based in technology acceptance model or innovation adoption, the research on digital management policy is rather limited. We intend to fill this research gap. As such, we first organize two categories of smart work and smart commerce, and investigate the representative service models, four service models were reviewed for each category respectively. Next, the three policy related constructs are extracted, which are QoL(Quality of Life), public impacts in both the positive and negative ways. Finally, empirical analysis following the Delphi principle was conducted to investigate the policy implications. The results offer useful insights for the further research in digital convergence related policy areas.

• Journal of Environmental Science International
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• v.30 no.9
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• pp.709-717
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• 2021

This study evaluated the growth, physiological responses and productivity based on the intercropping ratio of cherry tomato (Lycopersicon esculentum L.) with basil (Ocimum basilicum L.). on the rooftops to determine out the efficient ratio in urban agriculture. From April to September 2019, an experiment was conducted on the rooftop of Konkuk University Glocal Campus. Cherry tomato and basil were selected as companion plants for eco-friendly urban agriculture on the rooftops. Each plot was created with a width of 100 cm, length of 100 cm, and height of 25 cm. After installing drainage and waterproof layers from bottom to top, substrate was laid out with a height of 20 cm. Intercropping ratio was consisted of a single tomato plant (TC), 2:1 tomato to basil (T₂B₁), 1:1 tomato to basil (T₁B₁), 1:2 tomato to basil 2 (T₁B₂), and a single basil plant (BC), were conducted using a randomized complete plot design with five treatments and three replication (a total 15 plots). Measurements were divided into growth, physiological responses, and productivity parameters, and detailed items were investigated and analyzed by classifying them into plant height, leaf length, leaf width, number of leaves, root length, root collar caliper, chlorophyll contents, fresh weight, dry weight, number of fruit, fruit caliper, fruit weight, and sugar content. Comparative analyses of cherry tomato with basil plants by intercropping ratio, growth, physiological, and productivity responses are determined to be efficient when the ratio of cherry tomato to basil ratio is 2:1 or 1:1.

• Journal of the Korea Convergence Society
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• v.9 no.12
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• pp.295-299
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• 2018

The aim of this study was to evaluate the association between the level urine cotinine and periodontal diseases in Korea adults. The date from the 2014, 2015 Korean National Health and Nutrition Survey were used, and 5,146 subjects over 30 years were included in the analysis. Periodontal disease was assessed using the Community Periodontal Index. Binary logistic regression model was used to estimate the odds ratio with 95% confidence intervals. There was a 2.08-fold (95% CI; 1.73-2.05) increased in the odds of periodontal disease for those with any ETS exposure compared with those with non-smokers following adjustment for sex, age, education, and income. The level of urine cotinine also showed a dose-dependent increase in extent of periodontal disease. Among persons in the Korea who had never used tobacco, those exposed to ETS were more likely to have periodontal disease than were those not exposed to ETS. In the future, voluntary compliance of smokers to measures to reduce ETS exposure should be encouraged.

• Communications of the Korean Mathematical Society
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• v.12 no.3
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• pp.797-812
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• 1997

For analytic functions we give an expression for the kernel $K_n$ of the remainder terms for the Gauss-Radau and the Gauss-Lobatto rules with end points of multiplicity r and prove the convergence of the kernel we obtained. The error bound are obtained for the type $$\mid$R_n(f)$\mid$ \leq \frac{1}{\pi}l(\Gamma) max_{z \in \Gamma} $\mid$K_n(z)$\mid$ max_{z \in \Gamma} $\mid$f(z)$\mid$$, where $l(\Gamma)$ denotes the length of contour $\Gamma$.

• Journal of Convergence for Information Technology
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• v.12 no.1
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• pp.135-143
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• 2022

In this study, the antioxidant and anti-inflammatory properties of Colpomenia sinuosa extracts were identified. Antioxidant experiments included DPPH, ABTS, nitrite scavenging experiments, and FRAP, polyphenol concentration measurements, flavonoid concentration measurements. DPPH assay results showed an antioxidant function of 2.821 mg ascorbic acid/g extract. ABTS assay results showed an antioxidant function of 3.923 mg ascorbic acid/g extract. nitrite assay results showed an antioxidant function of 17.89 mg ascorbic acid/g extract. In FRAP, 1 mg of the Colpomenia sinuosa extract showed a reduction of 2.062±0.177 ㎍ of ascorbic acid. For polyphenols, 62.85±3.18 mg/g was shown. Flavonoids showed 10.01±0.24 mg/g. In the meantime, cell experiments showed cytotoxicity and anti-inflammatory functions. In cytotoxicity experiments, Colpomenia sinuosa extracts showed cytotoxicity of less than 20% and an inflammatory inhibition of 30.93±2.93% at a concentration of 100 ㎍/mL. These results indicate that Colpomenia sinuosa extract is available as functional cosmetic material.

• Health Policy and Management
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• v.32 no.2
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• pp.216-227
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• 2022

Background: Food insecurity may contribute to mental health indicators such as stress, anxiety, or depression. We investigated whether food insecurity was associated with mental health indicators and health-related quality of life (HRQoL) in a representative sample of the Korean population. Methods: This study enrolled 12,987 adults without a history of medically serious disease from the 2012, 2013, and 2015 Korea National Health and Nutrition Examination Survey. Household food security status was categorized as "food security," "mild food insecurity," and "moderate/severe food insecurity." The association between mental health and HRQoL was evaluated using a multivariate logistic regression model with food security as the reference group. Results: The adjusted odds ratio of adverse mental health or low HRQoL increased significantly in mild or moderate/severe food insecurity compared to food security. In the moderate/severe food insecurity group, it was 1.98% (95% confidence interval [CI], 1.31-2.99) higher for perceived stress, 3.58% (95% CI, 2.44-5.26) higher for depression symptoms, 4.16% (95% CI, 2.68-6.45) higher for suicidal ideation, and 2.81% (95% CI, 1.91-4.15) higher for quality of life. Conclusion: Food insecurity was strongly associated with negative mental health status and poor HRQoL. There is a need for a dietary support program that provides psychosocial support to those experiencing food insecurity.

• Journal of the Korea Convergence Society
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• v.8 no.1
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• pp.1-6
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• 2017

In this paper, we propose a new method for a correlative phase comparison direction finding(DF) which detects the arrival direction of radio waves by data fusing the calculated phase difference and the measured phase difference between the antennas when the radio waves are incident on the circular array antenna composed of 7 antennas respectively. The correlation type phase comparison method uses a uniform circular array(UCA) and a linear array method. The phase difference data calculated formally and the phase difference data measured in the test environment are fused with a correlation function, therefore, it is superior to the currently used phase comparison direction detection method. When the signal-to-noise ratio (SNR) of the received signal is 20dB and the inter-antenna distance to the wavelength of the received signal($L/{\lambda}$) is 0.5, the accuracy of the correlative DF is $1.7^{\circ}$ while measurement phase comparison's is larger than $2.5^{\circ}$, It can be used for electromagnetic signal monitoring and military direction detection.

• Journal of the Korea Convergence Society
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• v.8 no.8
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• pp.1-8
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• 2017

Recently, the technological development in the Internet of Things(IoT) field has grown rapidly worldwide and China is also expected to show a noticeable growth trend in this field. Therefore, the aim of this research is to analyze the recent trend of Chinese patents in the IoT field. China has been very active between 2010 and 2014, surpassing USA, and the this trend will accelerate in the future. The results of the analysis are as follows. First, the number of IoT-related patents in China increased rapidly from 2010 to 2014. Second, the major actors that led this quantitative increase are firms including ZTE and higher education institutes such as Nanjing University of Posts and Telecommunications. Lastly, major technological fields and the convergence networks amongst those fields were analyzed. As a result, it was found that the patenting activity in H04L was the most active and this field has led the convergence among other technological fields.

• Applied Science and Convergence Technology
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• v.23 no.5
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• pp.273-278
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• 2014

Using ab initio calculations, the effects of uniaxial, biaxial, and hydrostatic strains on the magnetocrystalline anisotropy of $L1_0$-orderd FePt and CoPt alloys were systematically investigated. Interestingly, the rates and the signs of magnetocrystalline anisotropy changes of FePt and CoPt were determined by the directions and dimensions of strains. The calculation results are consistent with the previous experimental observations and are expected to provide directions to tailor magnetic properties of various types of $L1_0$-ordered FePt and CoPt systems.