• 대한공업교육학회지
• /
• v.31 no.1
• /
• pp.63-85
• /
• 2006

This study was performed to deduce the constituents of competence for the practical duty in technical high school's heat treatment and tensile test practice. In order to accomplish this purpose 1) the constituents of competence for the practical duty were deduced through the job analysis and the skill hierarchy analysis of heat treatment and tensile test, 2) the deduced constituents of competence for the practical skill performance were correspond to the Mager's five performance type, that is, discrimination (knowing when to do it, knowing when it's done), problem solving (how to decide what to do it), recall (knowing what to do, knowing why to do it), manipulation (how to do it) and speech (how to say it). The results of this study will be helped to the selection of learning objective, learning content, instruction and evaluation method.

• 대한공업교육학회지
• /
• v.37 no.2
• /
• pp.99-125
• /
• 2012

The objectives of this study was to apprehend the displaying components by comparing and analyzing the ten types of construction textbooks used in Technical high schools by elaboration theory by Ferigeluth, and to supply preliminary data for the following revising textbooks. To achieve them, first, comparable units were excerpted by analyzing between the national textbooks of 7th curriculum and the new revised curriculum used in Technical high schools. Second, each five types of 7th and new curriculum textbooks were compared and analyzed by seven requisites in the Elaboration theory by Reigeluth. As the results of the study, first, elaborating process like conceptual, procedural, and theoretical elaboration has been applied to the different subjects according to their properties. Second, cognitive strategy activator among the seven strategies was widely used. Whereas, analogy was not applied to all the ten types of the text books. In addition, Learning prerequisite sequence was presented with only simple picture and explanation, and it was inadequately used in practice. Third, summary was more used in 7th curriculum text than the new revised text. Fourth, six strategy components were widely used to all texts except construction and materials in the five types of texts. Lastly synthesis of theory and practice was more used than summary in theory subjects and learner control was more used in the subject of the synthesis of theory and practice.

• Resources Recycling
• /
• v.18 no.3
• /
• pp.55-61
• /
• 2009

Dewatering process to remove water from pigment sludge was important in the diverse aspects of the improvement of product quality, curtailment of the drying cost and the transportation. It was difficult to dewater pigment particles with the mechanical forces because the size was fine under $5{\mu}m$. Thermal filter press dewatering equipment composed of squeezing plate and a fixed heating plate was developed to improve the dewaterability of pigment the sludge as supplying the heat from the fixed heating plate to the cake. Several tests that estimate the dewaterability for pigment sludge as with or without squeezing process and the difference of dewatering time was conducted with this equipment. Dewaterability of thermal dewatering under squeezing process was increased about 20% compared with non squeezing process. Under squeezing process, thermal dewatering tests changing dewatering time with 70 and 80 minute were conducted respectively. The water content of cake was more reduced at dewatering time of 80 minute compared with 70 minute, and dewatering velocity was also decreased, which caused the productivity of thermal filter press to drop. It was observed that clogging of filter cloth didn't almost occur because the liquid was discharged from cake layer easily. In this research, it was resulted that the squeezing process and long dewatering time were effective to improve the dewaterability of pigment sludge. So, this thermal filter press equipment was useful for dewatering the fine particle sludge like pigment.

• Korean Journal of Agricultural Science
• /
• v.6 no.1
• /
• pp.65-68
• /
• 1979

Water of river gets great concern about its quality, which might be polluted with pollutant from various industrial plants booming along the river sides in recent years. As a first step to prevent any applciable damage due to water pollution, survey on the water quality of Keum river at Sintanjin, Maepo, Taepyongri, Kongju, Puyeo and Kanggeng, six regions was conducted during september, 1977 through august, 1978 and the results were summarized as follow: 1. There were no significant regional and monthly difference in pH, $NO_2-N$, and $NO_3-N$ of water. 2. The BOD at Puyeo, Kanggeng was 3.9 to 5.6, 5.6 to 6.0 ppm, respectively, and those values reached the limiting level for tap water sources. 3. The BOD at Maepo, where Daejeon streams meet, was found 1.9, 3.0, and 2.1 times higher than those at Sintanjin region, during september, october and november, respectvely. 4. Content of DO was $7.6{\pm}3.8ppm$ in all surveyed regions and varied with water temperature and regional difference. 5. There were found regional difference and monthly difference in water hardness, suspended solid and $NH_3-N$.

• Management & Information Systems Review
• /
• v.36 no.3
• /
• pp.51-70
• /
• 2017

The purpose of this study is to examine the level and effectiveness of youth entrepreneurship and to analyze the relationship between entrepreneurship level and career change perceptions, And suggested ways of mutual cooperation and cooperation for activating entrepreneurship education and career education. The research hypothesis is the effect of entrepreneurship on career recognition, the mediating effect of program satisfaction on entrepreneurship and career awareness, and the difference in entrepreneurship change before and after participation in the program First, all factors such as innovativeness, risk sensitivity, entrepreneurship, autonomy, achievement desire, etc., Which are components of entrepreneurship, have positive influence on career recognition. Second, the mediating effect of program satisfaction on entrepreneurship and career recognition has positive effects on innovativeness, enthusiasm, autonomy and achievement desire. However, the risk sensitivity was not significant. Third, as a result of analyzing the difference of change before and after entrepreneurship education, all components of entrepreneurship were analyzed as positive (+). Considering these findings, it is necessary to improve the current method and content of entrepreneurship education to focus on student participation and experience. Second, it is necessary to coordinate and manage entrepreneurship education councils in government ministries with various stakeholders. Third, it is expected that future-oriented education will be possible if software education, entrepreneurship education and career education are integrated and operated in preparation for the fourth industrial revolution.

• Food Science and Preservation
• /
• v.13 no.5
• /
• pp.629-633
• /
• 2006

Pinus rigida Miller leaf extract (PRLE) showed antimicrobial activity remarkably against food pathogenic and spoilage bacteria at concentrations of $100{\sim}250{\mu}g/mL$. Alcohol-soluble PRLE had higher antimicrobial activity against Staphylococcus aureus and E-coli than any other-soluble PRLE such as butanol, ethyl acetate, ether and water. As PRLE concentration increased alcohol-soluble PRLE increased the remarkable inhibitory zone of microbial growth on the microbial media. PRLE showed good stability against temperature and pH in the range of $40{\sim}150^{\circ}C$ and $4{\sim}11$, respectively. This may indicate that PRLE can be a potential anti-microbial agent for industrial application. In addition, SEM of Listeria monocytogenes suggested that it antimicrobial component would perturb the functions of microbial cell membranes synergistically. In the feeding experiment the formaldehyde content in the serum of formalin-fed and PRLE-treated me decreased remarkably due to the lysis of formaldehyde and the rate of hemoglobin biosynthesis was recovered to the orignal state within a short breeding time.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.46 no.5
• /
• pp.57-70
• /
• 2009

A CAD design drawing based on vector data that is very important art work in industrial fields has been considered to content that the copyright protection is urgently needed. This paper presents a watermarking scheme based on k-means++ for CAD design drawing. One CAD design drawing consists of several layers and each layer consists of various geometric objects such as LINE, POLYLINE, CIRCLE, ARC, 3DFACE and POLYGON. POLYLINE with LINE, 3DFACE and ARC that are fundamental objects make up the majority in CAD design drawing. Therefore, the proposed scheme selects the target object with high distribution among POLYLINE, 3DFACE and ARC objects in CAD design drawing and then selects layers that include the most target object. Then we cluster the target objects in the selected layers by using k-means++ and embed the watermark into the geometric distribution of each group. The geometric distribution is the normalized length distribution in POLYLINE object, the normalized area distribution in 3DFACE object and the angle distribution in ARC object. Experimental results verified that the proposed scheme has the robustness against file format converting, layer attack as well as various geometric editing provided in CAD editing tools.

• Polymer(Korea)
• /
• v.37 no.4
• /
• pp.518-525
• /
• 2013

To improve the mechanical properties of polypropylene (PP) biocomposites reinforced with sulfuric acidtreated green algae (SGA), SGA/graphite nanoplatelets (GNP)/PP biocomposites were prepared and their properties were evaluated depending on the particle size and content of GNP. The flexural and impact strength of SGA/GNP/PP biocomposites decreased with the addition of GNP, whereas the flexrual and storage moduli were greatly improved with increasing GNP loading. SGA/GNP/PP biocomposites reinforced with GNP5 showed generally better mechanical properties compared to that reinforced with GNP15 mainly due to the improved dispersion of the smaller GNP. SGA/GNP/PP biocomposites reinforced with GNP5 showed a lower resistance to the thermal expansion because the relatively uniform dispersion of smaller GNP was responsible for the effective heat transfer to the polymer matrix. As a result, SGA/GNP/PP biocomposite was acceptable for the general purpose application due to the improved flexural resistance, storage moduli, and damping characteristics.

• Journal of Adhesion and Interface
• /
• v.2 no.3
• /
• pp.25-32
• /
• 2001

Ethyl cyanoacrylate (ECA) is used as an instant adhesive, and it can be readily polymerized by moisture in air without any initiator and applied for industrial products and ohome use. However, pure ECA monomer is low-viscosity liquid at room temperature that flows into substrate surface. To thicken the instant adhesive, poly(methyl methacylate)(PMMA) is often added in it commercially. Another disadvantage of instant adhesive polymer is its brittleness In this study, functional polymers including PMMA for an additive of ECA were prepared to increase viscosity of the monomer and flexibility of the adhesive atthe same time The additives, P(MMA-VAc-EVE), were synthesized by radical copolymerization of MMA with VAc and EVE having low glass transition temperature (Tg). The additives were added to ECA to get functional instant adhesives. The chemical structures of the additives and ECA polymers were confirmed by $^1H$ NMR and FTIR, and their physical and mechanical properites were also evaluated. The Tg of the obtained additives decreased with increasing the content of VAc or VAc-EVE, indicating more improved flexibility. In addition, functional instant adhesive containing the additives showed higher bonding strength than that of the existing one.

• Food Science and Preservation
• /
• v.10 no.3
• /
• pp.354-359
• /
• 2003

This study was conducted to investigate the fermentation characteristics of kimchi treated with different methods of water extracts of powdered green tea(GT). Four different kimchis, the SB-kimchi(control) which was not treatment of the extracts, SG-kimchi prepared with Chinese cabbage(CC) salted in 1％ GT containing 10％ brine, DG-kimchi prepared with CC dipped in 1％ GT for 30 min after salting, MS-kimchi prepared with the salted CC mixed with 1％ GT containing seasonings. All kimchis was fermented at 10$^{\circ}C$. The pH of treated-kimchis were maintained higher than those of control products during fermentation, but it showed no big difference between each treated groups. Total microbe of SB-kimchi(6.27-9.37 cfu/mL) was higher than those of GT-treated kimchi(5.17-9.20) during fermentation. The ratio of lactic acid bacteria against total microbe was higher than the treated kimchis. Total polyphenol content of kimchi was 52.75 mg％ in DG-kimchi, 47.71 mg％ in MS-kimchi, 44.89 mg％ in SG-kimchi, 30.70 mg％ in SB-kimchi on the 5th days of fermentation. Scores of crispy taste of SG- and DG-kimchi on the 5th days of fermentation was 4.03 and 4.01 points, respectively which was higher than control products. Scores of fishy and hot taste of GT-treated kimchi were lower than those of control products during all fermentation periods.