• Journal of the Institute of Electronics Engineers of Korea SC
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• v.49 no.1
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• pp.47-56
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• 2012

Bicycle has a large amount of kinetic energy available for energy harvesting technology in its speedy and balanced riding movement. Systematic and realistic analysis of its dynamic property is essential to improve the efficiency of energy harvester. However, there has not been enough researches about precise measurement or analysis of bicycle dynamics on real roads. This study aims to investigate the characteristics of vibrational movement of bicycle using MEMS-based accelerometer and to develop a prototype of electromagnetic energy harvester with nonlinear behavior which is proper to the random vibrations accompanied in bicycle riding. The vibrational components have average magnitude of 1 g and turn out to be independent of riding speed. The developed prototype of energy harvester was installed on a front port of a bicycle to use this ambient vibration and generated an average electrical power of 1.5 mW which is enough to support power for most of portable sensors and short range radio-frequency communication. Further study about isolation of vibration from a rider and conversion efficiency is ongoing. The developed energy harvester is expected to be a platform technology for sustainable portable power supply for various smart IT devices and applications.

• Journal of the Korean Society for Railway
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• v.20 no.4
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• pp.529-538
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• 2017

There has been much interest in optimizing the halting patterns of high-speed trains, for example by introducing more non-stop trains to supply faster train service to the passengers, which could later bring about a discussion about introducing new high speed train service with differentiated price and service. In general, halting patterns can be considered by constructing an efficient line plan, in which all demand should be covered and the total travel time can be reduced as much as possible. In this study, we present a two-step process based on two optimization models. One is to minimize total kilometers of trains to run on each route ; this will be done using a line planning model under the assumption of all-stop patterns. Then, in the next step, the all-stop patterns are optimally decomposed into several halting patterns in order to minimize the total travel time. We applied the two-step process to the latest demand data in order to develop KTX halting patterns as well as to determine the frequency of each line and compare the current line plan with the optimized one.

• Journal of Digital Convergence
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• v.14 no.7
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• pp.403-409
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• 2016

This study is a food shopping experience of omni-channel. Food threats and healthy living concerns bring different channels in led to increase reasonable way such as various demand. Omni-channels should be premised on understanding customer behavior as well as empirical user types in which considerations including the value of experience and understanding consumer behavior. Online survey result showed that, (1)offline food shopping, major retail store with quality, buy fresh food directly 2~3 times a month (2)online food shopping, e-commerce site with costs, buy fruits & nuts 2~3 times a month. After in-depth interview with eight high quality participants, I analyzed needs for food shopping experience in regard to the four steps food purchasing journey then derived a persona with integral value 'health' and 'diet'. It is classified into two types. One is the primary persona, family and health oriented, considering household money 'saving', and other is secondary persona, work and personal oriented, looking forward to 'automatic supply'. The result of this study provided an insight that help us explore ways to resolve function and services in the context of a healthy and balanced diet for improving food shopping experience of omni-channel.

• Membrane Journal
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• v.27 no.6
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• pp.487-498
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• 2017

In this study, pervaporation performances of water/methanol and water/butanol mixture were evaluated using zeolite 4A membranes manufacutred by FINETECH by experimental works and numerical modeling. Permeation and separation characteristics, such as flux and separation factor, were analyzed by gas chromatography (TCD) and liquid nitrogen traps. Experiments have shown that water is selectively separated from a mixture of water and methanol (separation factor up to approximately 250) and water and butanol (separation factor up to approximately 1,500). Generalized Maxwell Stefan (GMS) theory was implemented to predict pervaporation behaviors of water/alcohol mixtures and diffusional coefficients of zeolite layer were obtained through parameter estimation using $MATLAB^{(R)}$ optimization toolbox. Since the pore size of zeolite 4A are much larger than kinetic diameter of water molecules and smaller than those of methanol and butanol, zeolite 4A membranes can be applied to in situ water removal process such as membrane reactors or hybrid reaction-dehydration process.

• Korean Chemical Engineering Research
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• v.56 no.1
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• pp.66-72
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• 2018

Corn stover is known as a good candidate for a functional food ingredient when the main lignocellulosic material, lignin, is used as bioactive materials as form of polyphenolic compounds. The purpose of this study was to determine the microwave extraction conditions under which total phenolic compounds (TPC) and flavonoid contents of corn stover were maximized. Microwave-assisted extracts using sulfuric acid ranging from 0 to 1.0 mol with extraction time between 40 and 240 sec were conducted by using response surface methodology (RSM). Microwave power showed significant effects (p<0.05) and the concentrations of TPC and flavonoids increased with increased level of microwave power and extraction time. The optimum conditions for corn stover extraction were determined as 698.6 W, 240 sec, and 0 mol sulfuric acid, and the predicted value of TPC and flavonoid is 82.4 mg GAE/g DM and 18.1 mg/g DM, respectively. Microwave extraction was evaluated as an economic process with low energy consumption, short extraction and high extraction yield of bioactive including TPC and flavonoids compared to conventional extractions.

• Journal of the Korean Data and Information Science Society
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• v.22 no.6
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• pp.1145-1152
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• 2011

This study was conducted to estimate genetic effects on economically important traits for genetic improvement in Hanwoo by using the real-time ultrasound measurements for longissimus dorsi muscle area (LMA), backfat thickness (BFT), and marbling score (Marb). The phenotypic data were obtained from 1,648 pedigreed cows, and general linear models were applied to test the effects of age, region, and body condition socre. The cows between 50 and 60 months of age had the greatest scores for LMA and BFT, and Marb (P<0.05). The cows in region C had the greatest scores for body condition socre, LMA and BFT, while in region J Marb was the lowest (P<0.05). There was positive relation with LMA, BFT, and Marb according to increase body condition socre. Heritabilities for LMA, BFT, and Marb were estimated as 0.136, 0.351, and 0.236, respectively. These results would provide primary information for the efficient implementation of genetic improvement schemes in Hanwoo.

• Microbiology and Biotechnology Letters
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• v.30 no.1
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• pp.51-56
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• 2002

An antitumor substance was purified from the culture filtrate of phytopathogenic fungus Alternaria brassicicola SW-3 isolated from soil of a chinese cabbage patch, and its characteristics were investigated. Antitumor activity of A. brassicicola SW-3 was measured by MTT assay. The cytotoxic activity against human cancer cell line was detected in the culture filtrate of A. brassicicola SW-3, but no activity found in mycelium. Antitumor substance was isolated from the culture broth by ethyl acetate extraction and purified by silica gel column chromatography. Structure of the purified compound was analyzed by the instrumental analysis such as $^1$H-NMR, $^{13}$ C-NMR and IR spectroscopy. The purified fungal metabolite of an A. brassicicola SW-3, consists of 11 carbon chain with two hydroxyl groups and two epoxides which is identical to depudecin. The $IC_{50}$/ values of the active compound identified as depudecin were $69\mu$g/mL and $57\mu$g/mL against mouse melanoma B16BL6 cell line, and human hepatoma SK-HEP1 cell line, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.582-593
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• 2016

This study is a qualitative one that used a phenomenological study method to provide basic data for nursing practice by understanding the essence and meaning of middle aged men's hemiplegic experience after stroke. At D hospital which is located in S city, 8 hemiplegic participants who were hospitalized between 24th November, 2014, and 6th December, 2014, participated in in-depth interviews. The experiences of the participants were categorized into 6 criteria, viz. 'Thorny path on a long journey', 'Broken brakes', 'Crossroads of the mind', 'Burden of head of household', 'Signpost that lights the darkness', and 'Route to a second life', and 16 theme clusters were included in these categories. As the sequelae and complications, such as physical pain, psychological conflict and role disorder, due to stoke in middle aged men, seriously affect their quality of life, this study attempted to understand the effect of these problems and provide new insight into nursing practice. Also, it is important to prevent the recurrence of stroke in the patients, facilitate their recovery, and help them to maintain healthy lives through the reestablishment of their role in the home and society, including through the resolution of their physical and psychological problems.

• Korean Journal of Poultry Science
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• v.20 no.4
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• pp.209-216
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• 1993

This study was conducted to classify Korean native chicken(KNC) and imported chicken by phenotypic performances and DNA fingerprinting. Two lines, KNC and White Leghorn(WL) , of chicken were maintained in the laboratory of Yeungnam University. Economic traits (body weight, sexual maturity, hen-day egg production, egg weight) and phenotypic characteristics (body-type, head, feather, shank) were checked. The DNA fingerprinting was analyzed for both breeds. The growth rate of the KNC was similar to WLS and sexual maturity of the KNC came later than WL. Hen-day egg production of the KNC was also slightly lower than the WL. The egg weight was about 10g lighter than WL. There was no difference in body weight of female KNC compared to the WL after 28 weeks. The study confirms difference between KNC and WL in DNA fingerprinting as well as its outlook. Thus, we suggest that these should be tested in nationwide districts about chickens known as the KNC using DNA fingerprinting. Then, the confirmed KNC populations should be maintained and used for the genetic improvement. Finally, only confirmed KNC should be in market which induce consumer to seek the KNC by its favorite.

• Membrane Journal
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• v.23 no.5
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• pp.352-359
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• 2013

In the present study, $CO_2$ permeation through a hydrophilic NaY zeolite membrane was studied under permeate evacuation mode for $CO_2$ single gas, $CO_2-N_2$ and $CO_2-O_2$ binary mixtures, and $CO_2-N_2-O_2$ ternary mixture. It was reconfirmed that the $CO_2$ permeation was governed by surface diffusion and the $CO_2$ selectivity was induced from blocking effect of adsorbed $CO_2$ molecules. The $CO_2$ permeance measured in permeate evacuation mode was much lower than that done in He sweeping mode, but was comparable to that obtained under feed pressurization mode. The NaY zeolite membrane showed a considerable $CO_2$ separation for $14%CO_2-80%N_2-6%O_2$ mixture : $CO_2$ permeance was about $1{\times}10^{-7}mol/m^2secPa$ and $CO_2$ selectivity was more than 10. Therefore, it was concluded that NaY zeolite membrane was one of promising membranes for post-combustion CCS process.