• Journal of Korean Home Economics Education Association
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• v.16 no.4 s.34
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• pp.1-8
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• 2004

The purpose of this study was to investigate as to how much of changes has occurred in the newly revised Home Economics Textbooks required by the 7th Curriculum as compared to those by the former 6th Curriculum. and to seek future policy direction which can be improved even better. if any. for further revision. To implement this proposal, this study employed 8 different textbooks published among 12 textbooks developed for the 7th Curriculum for data base. The results of this study were as follows: It was covered such areas of change and develope in the composition of category and system in the Home Economics Textbooks required by the 7th Curriculum as compared to those by the former 6th Curriculum. The whole system of textbook was composed of cover page, the inside of a book cover. the title page, introduction. table of contents. appendices. It was same in the total pages with the exception of table of contents. appendices. the inside of a book cover and it was much alike in contents of introduction. In the aspect of the unit system of the textbooks. their whole flows were similar to each other. but the writers' intention and the stress on the focal points had appeared well in topic introduction and texts for the units of the textbooks. In addition. it can be said desirable that much more middle school teachers took a participation in the development of textbooks as textbook writers than before. In the organizational aspect of the sub-area organization of textbooks in the 7th Curriculum, it was not dispersed in grade 1, 2, and 3, but was centralized in a certain grade to increase its efficiency. The number of activity and experiment & practice that students could try to do actually were drastically increased compared to the 6th Curriculum. but it showed a wide difference between textbooks.

• Korean Chemical Engineering Research
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• v.58 no.1
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• pp.44-51
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• 2020

The basic catalyst 1-benzyl-3-methyl-imidazolium hexafluoroantimonate (BMH) was synthesized and analyzed by FT-IR and ¹H-NMR. A crystalized biphenyl-based epoxy was synthesized by using tetramethyl biphenol (TMBP) and epichlorohdrine. In order to consider the curing tendency of the synthesized BMH, the mass ratio was changed to 0.5, 1.0, 2.0 wt.% under heated conditions and the curing tendency was analyzed by differential scanning calorimeter (DSC). As a result, the BMH catalyst showed a fast curing result in the stepwise heating pr℃ess of the biphenol-A epoxy and the cationic polymer. From these results, the BMH catalyst showed excellent thermal stability as a potential heat curing catalyst. In addition, we considered the application possibility of epoxy molding compound (EMC) which required a skeleton structure and a high heat resistance because the synthesized biphenyl epoxy had a characteristic of rapidly lowering viscosity at a constant temperature and a rigid skeleton structure of biphenol. As a result, it was confirmed that the TMBP-based epoxy developed in this study was composed of a crystalline structure, and a curing reaction was observed with a Novolac resin at a high temperature. In the presence of a catalyst, a curing reaction was observed around 150 ℃ and thus TMBP-based epoxy was successfully applied as a raw material of EMC.

• Korean journal of communication and information
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• v.55
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• pp.5-32
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• 2011

This paper is a comparative analysis of constitutional decisions in which the Korea Consitutional Court and the United States Supreme Court applied the void for vagueness doctrine into free expression issues. Common aspects are: both courts applied the void for vagueness doctrine on the grounds that vague laws bring chilling effect on freedom of expression. Acknowledging inevitable uncertainties in lawmaking and legal jargons, however, both courts required minimum standards in the void for vagueness doctrine. In the cases where unclear legal meanings resulted in constitutional challenges, both courts adopted the "narrowing construction" by the courts or judges based on average/ordinary person's understanding. The biggest differences between the two constitutional courts are their approach to the degrees of vagueness allowed in free expression cases. The U.S. Supreme Court underscored the necessity of narrowly drawn, reasonable and definite standards. Meanwhile, the Korea Constitutional Court relaxed its standards in some cases such as the National Security Law cases, even though it admitted the possibility of curtailing the right to free expression. The Court reasoned that those laws, though vague, brought with bigger social interests and are necessary tools in dealing with changing world.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.5
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• pp.553-568
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• 2018

Chromophoric Dissolved Organic Matter (CDOM) plays a dominant role in absorbing UV-VIS light and is also important in the biogeochemical carbon cycle due to the production of carbon dioxide from photo-oxidation at the sea surface in marine environments. Since absorption by CDOM was recently found to be responsible for increasing the energy absorbed in the mixed layer by 40 % over pure seawater, the importance of CDOM absorption in seawater for increasing sea surface temperature has come to be well recognized. We measured aCDOM and the absorption characteristics of CDOM during spring 2012 and 2014 in the southwestern East Sea. Distribution of CDOM in spring 2012 and 2014 was compared and S value was used to find the source of CDOM in the study area. As a result, the average $a_{CDOM}$ was $0.237m^{-1}$ ($0.009{\sim}0.988m^{-1}$) and the average S value was $16{\mu}m^{-1}$,which shows coastal properties. Also a positive correlation between Chl a and CDOM was observed ($r^2=0.34$), with an especially strong correlation near coastal stations. aCDOM in 2014 was about 40 % higher than aCDOM in 2012 during spring in the study area. This difference in aCDOM concentration resulted not only from annual variation but also from stratification and photobleaching in late spring 2012. This observation implies the possibility of flux of carbon dioxide into the atmosphere as a result of photo-oxidation in the East Sea.

• Korean Journal of Environment and Ecology
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• v.34 no.2
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• pp.142-156
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• 2020

This study surveyed Gyeongan Stream, a tributary of the Han River Drainage System, from April to October 2017 to investigate the characteristics of fish communities. The survey collected 40 species of 11 families from 48 survey stations using kick nets and cast nets. The dominant and subdominant species were Zacco platypus (48.0%) and Rhynchocypris oxycephalus (17.7%), respectively. The next most abundant species were Pungtungia herzi (6.8%), Z. koreanus (5.0%), Carassius auratus (4.3%), Squalidus gracilis majimae (2.7%), and Rhodeus notatus (2.5%). Among the fish collected, 14 species (35.0%) were Korean endemic species, and the exotic species were Micropterus salmoides, Lepomis macrochirus, and Cyprinus carpio (Israeli type). The land-locked species were Plecoglossus altivelis, Rhinogobius brunneus, and Cottus koreanus, while the species sensitive to climate change was C. koreanus. The community analysis showed that the dominance was higher at the uppermost stream station, whereas diversity and abundance tended to be lower at the upstream station and higher toward the downstream station. The community structure was largely divided into rivers (uppermost stream, upstream, and middle-lower stream) and lake. The river health was mostly good (23 stations, 47.9%) and fair (15 stations, 31.3%). Comparison with past surveys showed that 12 species identified in the past surveys did not appear in this survey; nine species appeared for the first time in this survey; and the ecosystem disturbance species - M. salmoides and L. macrochirus - tended to spread more widely gradually.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.21 no.1
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• pp.27-34
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• 2015

Heating patterns depending on the packaging materials were examined in order to investigate the causes of thermal deformation of packages used for ready-to-eat foods for microwave heating due to the non-uniformity of microwaves. Physical properties including tensile strength, heat-resistance and elongation of four different CPP grades were compared. High retortable CPP had higher sealing strength and heat resistance compared to the conventional CPPs. All CPP samples tested were proved to have melting temperatures around $160^{\circ}C$. However, they were all thermally deformed by microwave heating due to a limited penetration of microwave and non-uniform heating within the spicy sauce of high viscosity contained high salt, especially on the above the filling line and sealing edge of pouches. When the laminated stand-up pouches composed of G-PET/PET/PET/CPP and G-PET/PET/NY/CPP were retorted and microwaved, significant deformations were noticed in both samples after retorting. Besides, pouches contained titanium dioxide showed more intense thermal deformation than the control. When the $10{\mu}m$ aluminium foil was affixed on the pouch, small thermal deformation was observed only in the bottom layer. More studies are required to prevent the thermal deformation of packaging materials used for RTE foods during microwave heating by developing the technologies to increase the thermal stability of CPP layer and the modification of packaging design to modify the microwave access into the package.

• Journal of Chest Surgery
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• v.29 no.5
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• pp.510-516
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• 1996

Cardiopulmonary bypass cannulas are usually characterized by the French number. However this de- scription provides only the external diameter of the cannula, which gives no information about the press- ure-flow characteristics of the cannula itself. A standardized system to describe the pressure-flow characteristics of a given cannula has recently been proposed and has been termed the M-number It is reported that the pressure-flow characteristics of a particular cannula can be determined from a novo- gram or chart, if the experimentally derived M-number of the cannula is known. In this regard, we conducted an investigation to analyze correlation between experimentally and clinical y derived M-numbers using three different sizes of pediatric aortic cannulas in fifty cardiac patients on cardiopulmonary bypass. The clinical and experimental M-numbers showed a strong correlation. The clinical M-numbers were typically 0.)5 to 0.55 greater than the experimental M-numbers. The clinical M-numbers also showed an inverse relationship to the temperature change of the patient, most probably due to an increase in blood viscosity from hypothermia. This inverse clinical M-numbersltemperature re- lationship was more marked in higher M-number cannulas. The clinical data obtained in this study suggest that the experimentally derived M-numbers correlated strongly with the clinical performance of the cannula with the significant influence of the temperature.

• Food Science and Preservation
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• v.9 no.2
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• pp.212-220
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• 2002

Spray drying was used a means for microencapsulation of Aster scaber and Aster glehni. The optimum conditions of spray drying were found to be 210$^{\circ}C$ for the inlet temperature and 5 $m\ell$/min for the feeding rate. The color difference decreased by 12∼25 % far the herb extracts depending on storage temperatures. With an increase in storage temperature, color of the control changed considerably compared to microencapsulated powders. This is due to the fact that wall materials minimized effect of oxygen on the herb extracts. Microencapsulated powders in the amounts of 50 ppm and 250 ppm added to hydrogenated soybean oils led to lower acid values and conjugated diene values during 6 day storage. Compared to the control, the herb extracts displayed 16∼48% increase in antioxidation effect, while the microencapsulated powders exhibited 46∼88% increase. Extracts also showed lower conjugated dienoic acid contents than those of the control. Although antioxidation effect of the microencapsulated powders did not prevail on the significant level in the early stage of storage of oils tested, it became predominant after one week of storage as wall materials were gradually degraded under the high temperature thereby releasing core material from the microcapsule.

• Polymer(Korea)
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• v.38 no.5
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• pp.566-572
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• 2014

Maleic anhydride (MAH) grafted polypropylenes (PP) (MAH-g-PP) were prepared by changing MAH content and styrene monomer (SM)/MAH mole ratio with different type PP, using a twin screw extruder. The types of PP were isotatic PP (iPP), block PP (bPP), and random PP (rPP) and dicumyl peroxide (DCP) was used as an initiator. The graft degree of MAH was confirmed by the existence of carbonyl group (C=O) stretching peak at $3100cm^{-1}$ of FTIR spectrum. Thermal properties of MAH-g-PP and PP/MAH-g-PP/pulp composites were investigated by DSC and TGA. There was no district change in thermal properties of PP/MAH-g-PP/pulp composites. Based on tensile properties and SEM pictures for fractured surface of PP/MAH-g-PP/pulp composites, MAH-g-rPP was the best as the compatibilizer and optimum formulation was MAH content of 1.0 wt%, SM/MAH mole ratio of 1.0, and melt index (MI) of 25 g/10 min. The rheological properties of the composites were investigated by a dynamic rheometer. The complex viscosity, shear thinning effect, and water uptake incresed with pulp content.

• Weed & Turfgrass Science
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• v.4 no.4
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• pp.295-307
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• 2015

Surveys of weed species in paddy fields were conducted to identify weed occurrence on July 2013. Total 237 sites of paddy fields in 9 City/Gun, Jeonnam Provinces in Korea were investigated. From the survey, 45 weed species in 18 families were identified and classified to 33 annuals and 15 perennials. Based on the occurrence ratio, the most weed species belonged to Poaceae (9 species) and 8 and 4 weed species belonged to Cyperaceae and Scrophulariaceae, respectively. These 21 weed species in the most four families accounted for 46% of total weed occurrence. The most dominant weed species in Korean paddy fields were Echinochloa spp. (18.5%), followed by Monochoria vaginalis (12.3%), Lemna perpusilla (8.2), Eleocharis kuroguwai (5.2%) and Scirpus juncoides (5.2%). The most dominant weed species in machine transplanting paddy fields were Echinochloa spp. (14%), followed by Monochoria vaginalis (12%) and in water seeded rice paddy fields were Echinochloa spp. (25%), followed by Monochoria vaginalis (11%). This information could be useful for estimation of future weed occurrence, weed population dynamics and establishment of weed control methods in paddy fields.