• Journal of The Korean Association For Science Education
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• v.2 no.1
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• pp.31-51
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• 1980

In order to research into the devel of the concept of movement and speed in our own way and compare with the Piaget's method, and then find out the formative period of such development, we have put the 192 primary school children as the model and obtained the following results. 1. As their grade upyards, all the experimental subjects showed the gradual progress generally regardless of sex or regions, while only the relative speed showed irregular progress. 2. There was no experimental subject which showed any remarkable sexual characteristics. But in the relative movement, the lower grade boys and higher grade girls made progress. In the subjects of circulation movement, intuition of speed, relative speed and speed of simultaneous movement, the boys marked better progress, whilst the girls were advanced a little in the speed of continuous movement with, different distance and time. 3. There was no conspicuous difference between the urban and rural areas, except a slight tendency that the urban children made better progress in the change of progressing direction, native continuous procedure of periodical movement, travelling road, and the speed of continuous movement with different distance and time whereas the rural children were more advanced in the relative movement, relative speed and intuition of speed. But it should be 'taken into consideration that the rural regions in our case were relatively developed in comparison with the traditional rural communities, which may explain about little regional difference. 4. Comparing our research results with the Piaget's theory, we have reached below results. Our research reports that the formative period of the conception of the problems of diverse progressing direction and a native continuous procedure of periodical movement was simultaneous, at the Piagetian level(at the fourth grade) which coincides with Piagetian theory. The travelling road should be made up a little lower at 2A/2B according' to Piagetian Level, whereas it was formed at the 4th grade as shown in our previous research. Intuition of speed should belong to the prior stage to concrete operation, but our research shows it was formed late at the 4th grade. Composition of displacement was made at the 6th grade, and it was almost equal to the first stage of formal operation(3A). But in the subjects of relative movement relative speed, the speed of continuous movement with different distance and time, relation and preservation of invariable speed, and accelerated motion, even 6th grade children marked a poor record. Summed up, the procedure conception as a basic movement conception coincides with the Piagetion level. But as for speed intuition, relative speed and speed fixation, it was Jar behind Piagetian level. Therefore it is required that we have to concentrate on the systematic training in these parts on the spot.

• Applied Biological Chemistry
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• v.29 no.3
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• pp.324-330
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• 1986

The responses of brain acetylcholinesterase(Ach-E) and plasma cholinesterase (Ch-E) activities were studied in chicknes given oral doses of Terbufos(S-tert-butyl thiomethyl 0,0-diethyl phosphorodithioate), an organophosphorus insecticide. The acute oral $LD_{50}$ of terbufos was 1.82mg/kg. The activity of plasma Ch-E was inhibited more rapidly than that of brain Ach-E, whereas recovery of plasma Ch-E activity was more rapid than that of brain Ach-E. Recovery of brain Ach-E and plasma Ch-E was followed the model $Y=a+b(log_{10}X)$. Brain Ach-E activity and plasma Ch-E were inhibited 83% and 94%, respectively, at 60min after administered oral $LD_{50}$. Brain Ach-E and plasma Ch-E was inhibited in vitro by Terbufos

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.7
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• pp.1028-1034
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• 2005

The purposes of this study were to: (a) identify students' patronage behaviors on university foodservice, (b) evaluate customers' perception and detect complaints on food service quality, and (c) recommend new design of food service operation by identifying relative importance of university foodservice attributes. The questionnaire was developed and distributed to 400 undergraduates. Statistical data analysis was completed using SPSS/Win 12.0 for descriptive analysis and conjoint analysis. The results of this study were summarized as follows: Students were patronizing university foodservice 3.4 times per week because of 'a short distance', 'a low price' and 'speedy meals' and evaluated overall satisfaction and value as low level. Customers were dissatisfied with eight among twelve food service attributes including handling customer's complain ASAP, According to conjoint analysis, price $(37\%)$ was considered as the most important factor and atmosphere $(30\%),\;food\;(22\%)$ and distance $(11\%)$ were the next factors. Profile 2, which had 4 attributes of a location within 6-10 min, comfortable circumstances, a meal served with 4 side-dish and dessert and a meal price of \2,000 firstly, were recommend as new food service operation model.

• KSBB Journal
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• v.22 no.6
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• pp.371-377
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• 2007

Polyhydroxyalkanoates (PHAs) are a family of microbial polyesters that can be produced by fermentation from renewable resources. PHAs can be used as completely biodegradable plastics or elastomers. In this paper, novel applications of PHAs in biosensor are described. A general platform technology was developed by using the substrate binding domain (SBD) of PHA depolymerase as a fusion partner to immobilize proteins of interest on PHA surface. It could be shown that the proteins fused to the SBD of PHA depolymerase could be specifically immobilized onto PHA film, PHA microbead, and microcontact printed PHA surface. We review the results obtained for monitoring the specific interaction between the SBO and PHA by using enhanced green fluorescent protein, red fluorescent protein, single chain antibody against hepatitis B virus preS2 surface protein and severe acute respiratory syndrome coronavirus surface antigen as model proteins. Thus, this system can be efficiently used for studying protein-protein and possibly protein-biomolecule interactions for various biotechnological applications.

• Journal of Sensor Science and Technology
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• v.24 no.6
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• pp.404-411
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• 2015

A stoichiometric mixture of evaporating materials for $BaAl_2Se_4$ single crystal thin films was prepared from horizontal electric furnace. To obtain the single crystal thin films, $BaAl_2Se_4$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy (HWE) system. The source and substrate temperatures were $610^{\circ}C$ and $410^{\circ}C$, respectively. The crystalline structure of the single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD). The carrier density and mobility of $BaAl_2Se_4$ single crystal thin films measured from Hall effect by van der Pauw method are $8.29{\times}10^{-16}cm^{-3}$ and $278cm^2/vs$ at 293 K, respectively. The temperature dependence of the energy band gap of the $BaAl_2Se_4$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)=3.4205eV-(4.3112{\times}10^{-4}eV/K)T^2/(T+232 K)$. The crystal field and the spin-orbit splitting energies for the valence band of the $BaAl_2Se_4$ have been estimated to be 249.4 meV and 263.4 meV, respectively, by means of the photocurrent spectra and the Hopfield quasicubic model. These results indicate that the splitting of the ${\Delta}so$ definitely exists in the ${\Gamma}_5$ states of the valence band of the $BaAl_2Se_4/GaAs$ epilayer. The three photocurrent peaks observed at 10 K are ascribed to the $A_1$-, $B_1$-exciton for n =1 and $C_{31}$-exciton peaks for n=31.

• Journal of Animal Environmental Science
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• v.15 no.2
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• pp.131-138
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• 2009

This study was conducted to find ways to control environment with the difference between body temperature and background temperature based on swine activity, and to apply to the environment control system of swine barns based on the findings. Following are the results. 1. Swine activity related to background temperature was achieved as color images and swine activity status was categorized into cold, comfortable, and hot periods with visualization system (thermal image system). 2. Thermal image system consisted of an infrared CCD camera, an image processing board - DIF (TH3100), an main computer (400Hz, 128M, 586 Pentium model) with C++ program installed. 3. Thermal image system categorizing temperatures into cold, comfortable, and hot was applicable to the environment control system of swine barns 4. Feed intake was higher in cold temperature, and finishing weight and weight gain per day in cold temperature were lower than others (p<0.05).

• Journal of Service Research and Studies
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• v.6 no.3
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• pp.29-40
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• 2016

Since the late 20th century, there has been much effort to improve the market value of media contents which are commercialized in a digital format, by fusing digital data of video, audio, numerals, characters with IT technology together. Then by what criteria and methodologies could the market value for the drama "Sons of the Sun" or the animated film 'Frozen', often referred to in the meida, be estimated? In the circumstances there has been little or no research on the valuation framework of media contents and the status of their valuation system development to date, we propose a practical valuation models for various purposes such as contents trading, review of investment adequacy, etc., by formalizing and presenting a contents valuation framework for the four types of media of movies, online games, and broadcasting commercials, and animations. Therefore, we develope computational methods of cash flows which includes production cost by media content types, provide reference databases associated with key variables of valuation (economic life cycle, discount rates, contents contribution and royalty rates), and finally propose the valuation framework of media contents based on both income approach and relief-from-royalty method which has been applied to valuation of intangible assets so far.

• Korean Public Health Research
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• v.44 no.4
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• pp.99-109
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• 2018

Objective : Health literacy (HL) is, defined as "the degree to which individuals have the capacity to obtain, process, and understand basic health information and services needed to make appropriate health decisions." Being old is one of the main risk factors with limited health literacy. This study aims to adapt Chew's health literacy scale into the Korean language and validate the scale for the use of the elderly. Methods : Data were drawn from the '2016 Seoul Survey on Elderly Health and Functional Assessment, which includes a total of 725 people aged 60 to 79. The sample was randomly divided into two groups for reliability and validity tests of the modified Chew's scale of 8 items. The Korean version of the questionnaire was developed by group translation, expert reviews, and forward-backward translation. Exploratory and confirmatory factor analyses were conducted to assess and validate the factor structure of the scale. Results : Results suggest the two-factor structure ("Understanding" and "Applying" of HL) with 8 items. Exploratory factor analyses of the first sample (n=400) revealed that the internal reliability of the scale was high (Cronbach's ${\alpha}=.904$). Principal axis factoring extracted two factors ("Understanding" and "Applying" of HL) and explained 78.3% of total variance (KMO=.872, Bartlett's ${\chi}^2=2431.3$, df=28, p<.001). Confirmatory factor analysis of the second sample (n=325) was performed and the two-factor model was supported (GFI=.960, CFI=.979, TLI=.969, RMSEA=0.075). Conclusions : This study provides evidence for adequate criterion and validity of the health literacy scale for the community dwelling elderly in Korea.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.1-12
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• 2021

Technologies for an MVDC(medium voltage direct current) distribution system are being considered as an effective alternative to overcome the interconnection delay issues of PV systems. However, the implementation of a DC distribution system might lead to economic problems because of the development of DC devices. Therefore, this paper deals with the scale of a PV plant based on its capacity and proposes hosting-capacity models for PV systems to establish a network to evaluate the feasibility of an MVDC distribution system. The proposed models can be classified as AC and DC distribution systems by the power-supply method. PV systems with hundreds of MW, dozens of MW, and a few MW can be categorized as large-scale, medium-scale, and small-scale models, respectively. This paper also performed modeling for an economic evaluation of MVDC distribution system by considering both the cost of AC and DC network construction, converter replacement, operation, etc. The profit was composed of the SMP and REC rate of a PV plant. A simulation for economic evaluation was done for the MVDC distribution system using the present worth and equal-principal costs repayment method. The results confirmed that the proposed model is a useful tool to evaluate economic issues of a DC distribution system.

• The Korea Journal of Herbology
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• v.34 no.2
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• pp.15-23
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• 2019

Objective : Reflux esophagitis (RE) is a disease that caused gastric acid reflux and inflammation due to unstable gastroesophageal sphincter, as increasing worldwide respectively. This study was conducted to evaluate the effect of Evodiae Fructus (EF) extract on chronic reflux esophagitis in rats. Methods : The EF was measured antioxidant activity, such as total polyphenol and total flavonoid contents, 1, 1-diphenyl-2-picrylhydrazyl (DPPH) and 2, 2'-azinobis-3-ethyl-enzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity. Rats were divided into 3 groups; Nor (normal group), Con (chronic acid reflux esophagitis rats treatment with water), EF (chronic acid reflux esophagitis rat treatment with EF 200 mg/kg body weight group). A surgically-induced chronic acid reflux esophagitis (CARE) model was established in SD rats, and treated with water or EF 200 mg/kg body weight for 14 consecutive days. Results : Administration of EF to rats of induction of chronic acid reflux esophagitis was found to reduce esophagus tissues injury. Reactive oxygen species (ROS) and produces peroxynitrite ($ONOO^-$) levels of esophagus tissues were significantly decreased in EF compared to Con group. As results of esophagus protein analyses, EF effectively reduce inflammatory-related factors ($NF-{\kappa}Bp65$, $p-I{\kappa}B{\alpha}$, iNOS, $TNF-{\alpha}$, IL-6), and increase anti-oxidant enzyme (Nrf2, HO-1, SOD, catalase, GPx-1/2). Conclusions : These results suggest that EF administration comfirmed that decreased esophagus tissues injury, oxidantive stress, anti-inflammation effect, and increased anti-oxidant effect. Therefore, EF was the potential to be used as a natural therapeutic drug.