• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.4
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• pp.331-336
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• 2012

This study was carried out to evaluate the wheat cultivation system to reduce costs and mechanize wheat production. A field study was conducted for 2 years (2009 to 2010) at the National institute of crop science, Iksan, Korea. We used working system I and working system II for the experiment. Working system I is used a multiple machine attached with a spreader tractor (seeding, fertilization, seed coverage, and weed control functionality) and working system II is used a multiple machine with a tractor which works for simultaneous job when seeding step (seeding, fertilization, and seed coverage). Sowing to harvesting operation time is 118 hours/ha for mechanize with conventional planting. Working system I is a multiple machine and a combine machine with a tractor, which worked 26 hours/ha lower than conventional planting. Working system II is 18 hours/ha lower than conventional planting. The reduced work efforts of working system I and II were 78% and 85% respectively. The growth and yield of wheat according to working system I and II is lower than conventional planting. Therefore, a multiple machine needs to study for appropriate seeding rate. Mechanization cost in consideration of the mechanical break-even point when the working system I is 3.7 ha and working system II is 4.2 ha. The farm income is enhanced by working system I (778,110 won/ha) and working system II (849,930 won/ha). The results showed that application of a multiple machine lowered costs of wheat production.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.4
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• pp.347-354
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• 1999

This experiment was carried out to determine the effect of maturity at harvest and inoculants on the quality of round baled rye(Secale cereale L.) silage at the experimental field of Grassland and Forage Crops Division, National Livestock Research Institute, RDA, Suwon in 1998. The experiment was consist of split-plot design with 3 replications. The main plots were 3 harvesting stages such as boot(20 April), heading(29 April), and flowering stages(14 May). The subplots wered inoculant treatments : control (untreated), inoculant A, and inoculant B. Acid detergent fiber(ADF), neutral detergent fiber(NDF), and in vitro dry matter digestibility (IVDMD) of rye silage were significantly increased with delayed harvesting date, but there was not significant difference between inoculants. Mean silage pH at flowering stage was the lowest(4.35), but the highest at early harvest(4.91). Inoculants significantly reduced acidity of silage compared with control. Dry matter(DM) content of the control was higher than that of inoculants. Ammonia-N as proportion of total N was below 10% which was maximum level of high quality silage. The addition of inoculants reduced ammonia-N. There were significant difference in organic acid contents between harvesting stages and inoculants. Lactic acid was increased with inoculants, but acetic and butyric acids were decreased. Various treatments increased colony forming unit(CFU) of lactic acid bacteria by 2 or 3 times compared with the control and the highest at flowering stage with inoculant B treatment. Results of this study indicate that use of microbial inoculant and harvesting after heading stage will improve the silage fermentation and quality of round baled rye silage.

• Archives of design research
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• v.12 no.4
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• pp.5-14
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• 1999

From the middle of 1970s were founded new basis for the development of craft through the co-operation of the civilians and the authorities. First, Korean Culture and Art Foundation founded in 1973 held the 'Invitation Exhibition for the Craft Artists All over the Country' in 1974 and 1975 and The National Museum of Modern Art held the 'Exhibition of Modern Korean Handicraft Art' in 1975. Second, the policy emphasizing the export and tourism provided the basis for the development of design for export goods and souvenirs of tour. H\therefore the exhibitions of such goods were held by many organizations. ] In 1970s departments of craft and design were newly established in the universities so that the third generation of Korean craft was on the rise and their groups began to hold exhibitions in commercial galleries. Reflecting on such circumstances, 1970s was the period of blossom for Korean craft while 1960s was a sprouting season.

• Korean Journal of Food Science and Technology
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• v.21 no.4
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• pp.468-479
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• 1989

The oxidative stability of the ramyon prepared with rapeseed oil fortified with antioxidants or blended with palm oil was studied to explore the possibility of substituting it for Imported frying fats and oils. Natural tocopherols, butylated hydroxyanisole(BHA), tertiarybutyl hydroquinone(TBHQ), and ascorbyl palmitate with citric acid were used at a level of 0.02 percent. Blended oils were prepared by adding a palm oil to the rapeseed oil at ratios of 7:3, 5:5, and 3:7(w/w), respectively. Ramyon samples were stored at $35.0{\pm}0.5^{\circ}C$. for 90 days. The values of parameters, such as peroxide value, unsaturation ratio, and dielectric constant, of the extracted oils were regularly determined. An organoleptic test for the flavor of the samples was also performed. The oxidative stability of the samples was estimated on the basis of the changes of the parameter values. The effectiveness of the antioxidants was in the order of TBHQ ${\gg}$ ascorbyl palmitate with citric acid>BHA>natural tocopherols. The oxidative stability of the ramyon prepared with the rapeseed oil containing 0.02 percent TBHQ was almost as good as that of the ramyon prepared with the palm oil. The stability of the ramyon prepared with the blended oil containing 70 percent palm oil was also as good as that of the ramyon prepared with the palm oil.

• KSBB Journal
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• v.15 no.4
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• pp.375-379
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• 2000

Alginate derivatives possessing various lengths of alkyl amine (C8, C12, C16) chain were prepared by oxidation followed by reductive amination of alginate and the products were characterized by spectral analysis. The surface tension critical micelle concentration (c. m. c) and solubility of a hydrophobic compound azobenzene were examined. Series of synthesized alginate-derived polymeric surfactants(APSs) reduced the surface tension. The dissolving capacity of APSs toward azobenzene was about half that of SDS. In order to investigate the capacity of metal adsorption Co and Pb were selected as a representative metal. The overall removal efficiency of APSs were high compared with that of alginate at pH 3.5 and 7 respectively. Major mechanism of the heavy metal removal is the complex of metal with carboxyl group.

• Applied Chemistry for Engineering
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• v.20 no.2
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• pp.140-144
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• 2009

Triethanolamine-type cationic surfactants were synthesized and their applications were established. The production of mono-, di-, and tri-TEA-EQ (triethanol-amine-esterquater) were dependent on the molar ratio of fatty acid and triethanolamine under the controlled reaction temperature. The structures were elucidated by $H^{1}$ NMR. Long-term stability was dependent on the amount of mono- and tri-TEA-EQ. When the amount of mono-TEA-EQ was increased, long-term stability was increased. However, the more tri-TEA-EQ made long-term stability decreased. Softening was dependent on the amount of saturated fatty acid, and re-wettability was counted on the amount of unsaturated fatty acid. Softening was measured by the method of sense estimation e.g. touching to home-towel. Absorption was determined to calculate the height of water on a towel after treatment.

• Clean Technology
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• v.12 no.4
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• pp.198-204
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• 2006

The modification of biodegradable polycaprolactone was accomplished by reactive extrusion with various contents of free radical initiator. Reaction conditions were in the temperature range of $130^{\circ}C$ to $180^{\circ}C$ with initiator contents of 0.1, 0.3, 0.5 and 1.0 wt%. To characterize the modified polycaprolactone (PCL), molecular weight was measured by gel permeation chromatography(GPC) and thermal, mechanical and rheological properties as well as biodegradability were measured. The modified PCL (MPCL) with 1% of initiator showed ca. 20% increase in crystallinity and ca. 50% increase in tensile modulus. Also, a large increase in rheological properties such as complex viscosity, storage and loss modulus was observed. The biodegradability of most MPCL was higher than that of virgin PCL.

• Membrane Journal
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• v.8 no.4
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• pp.210-219
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• 1998

Sulfonated poly(ether sulfone)(SPES) of various ion exchange capacity (IEC) was prepared by heterogeneous sulfonation with chlorosulfonic acid (CSA) to make hydrophilic ultrafiltration membrane for reducing fouling. The effects of CSA concentration, reaction temperature and reaction time has been investigated. The reaction was effective when the temperature is above 10$\circ$C and the CSA concentration is over 0.05 mol, although polymer chain has been significantly degraded. The substitution of sulfonic acid groups was characterized by FTIR and $^1$H-NMR. Transport properties and fouling test have been conducted to the modified SPES ultrafiltration rnembranrs by heterogeneors method. Membranes were obtained using DCM and PVP as a non-solvent and pore forming agent, respectively. Flux reduced and rejection increased with ion exchange capacity. Finger-like structure was disappeared and the thickness of top layer was increased. Dense membrane by non-solvent DCM and porous membrane by pore forming agent PVP was prepared. Fouling was reduced with increasing ion exchange capacity because of hydrophilicity.

• Korean Journal of Comparative Education
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• v.18 no.4
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• pp.163-186
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• 2008

This study intends to understand deeply the higher education evaluation accreditation system in Taiwan. Taiwan established newly the Higher Education Evaluation & Accreditation Council in 2005, an independent organization with the exclusive responsibility to execute evaluation. Three kinds of evaluation have been accomplished, including University Program Evaluation which assesses whole university management, Academic Fields Evaluation and Performance Evaluation which compare the superiority and inferiority among universities. The Accreditation system is applied only to Academic Fields Evaluation. For evaluation, each university presents a self-evaluation report, undergoes an visiting evaluation, makes out an evaluation report and lastly is notified of the result. The evaluation is divided into three results : pass, waiting observation and non-pass. According to an announcement in June 2008, the rate of non-pass universities reached the 15.7%. The non-pass universities are supposed to receive the disadvantaged in the admission number limit and take the following evaluation in the following year. Debates still exists concerning the eliminatory nature of the system and the announcement of achievement rankings through evaluation results. Other problems include the improvement of quality of evaluation committee members and the irrational evaluation standards. These problems will be meaningful for the development of the korean higher evaluation system.

• Elastomers and Composites
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• v.40 no.4
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• pp.249-257
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• 2005

Polyurethane(PU) prepolymers were prepared from polyol and diisocyanate. Unionized PU prepolymers were synthesized from poly(propylene glycol)(PPG, MW: 1000), 2,2-bis (hydroxymethyl) propionic acid(DMPA), and isophorone diisocyanate(IPDI) by prepolymer syhthesizing process. After PU prepolymers were dispersed into water, the physical properties were investigated by changing the molar ratio of polyol and diisocyanate. The results showed a stable state with the best physical properties when the prepolymer was composed of PPG/DMPA with hard segment=40%, NCO%=3.43%, [NCO]: [OH]=1.5: 1.0 in molar ratio, and was dispersed into water with 30% solid content. PU prepolymers also were synthesized with various molar ratio of PPG and DMPA. Upon higher molar ratio of DMPA, particle size of polyurethane dispersion(PUD) gradually decreased. PU-prepolymers prepared from the various blocking agents represented characteristic initial deblocking temperatures that depended on the blocking agents, and the beginning of deblocking occured within 30 mins on all the blocking agents used.