• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.2
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• pp.121-128
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• 2003

This study was conducted to investigate the effect of tall type mixtures and tall+short type mixtures on dry matter yield, botanical composition and quality. The experimental design includes two mixture types: Tall type mixtures(TM); orchardgrass(Potomac) 40+tall fescue(Fawn) 20+Festulolium braunii (Paulita) 10+perennial ryegrass(Reveille) 10+timothy(Climax) 10+red clover(Kenland) 5+alfalfa(Vernal) 5%) and tall+short type mixtures(TSM); orchardgrass(Potomac) 40+tall fescue(Fawn) 20+Kentucky bluegrass(Newport, turf type) 10+redtop(Barricuda, turf type) 10+perennial ryegrass(Palmer III, turf type) 10+red fescue(Flyer II, turf type) 5+white clover(Regal) 5%. The dry matter(DM) yield was higher obtained in TSM than that of TM, but there was no significant difference between TM and TSM. In the chemical composition, there was no significant difference between TM and TSM, but the content of cellulose, lignin were higher in TM than those in TSM(p<0.05). Also, the content of acid detergent fiber which affected dry matter digestibility was higher in TM than that of TSM. The crude protein dry matter yield was not observed significant difference between TM and TSM, but digestible dry matter(DDM) yield was higher in TSM than that of TM. In botanical composition, tall fescue, alfalfa and orchardgrass were highly maintained in TM but white clover, tall fescue and orchardgrass were highly, and redtop, red fescue were continuously maintained in TSM. In this experiment, DM yields and quality of two mixture types were no difference. However, the tall+short type mixtures(TSM) were more effective in enhancing the dry matter digestibility and DDM yield, and in maintaining the various botanical composition.

• Korean Journal of Organic Agriculture
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• v.18 no.3
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• pp.419-432
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• 2010

This study was conducted to determine effects of applying cattle slurry and mixed sowing with legumes such as hairy vetch or forage pea on productivity, feed values and organic stock carrying capacity of whole crop barley and rye as winter forage crops, and to obtain organic forages together with higher soil fertility. Experimental plots consisted of 7 treatments, which were non-fertilizer, chemical fertilizer (containing phosphate and potassium: P+K), chemical fertilizer (containing nitrogen, phosphate and potassium: N+P+K), organic fertilizer, cattle slurry, cattle slurry application (mixture with hairy vetch), and cattle slurry application (mixture with forage pea) plots. Each treatment was triplicates, and seven treatments were allocated in a completely randomized block design. For whole crop barley or its mixture crops, annual dry matter (DM), crude protein (CP), and total digestible nutrients (TDN) yields of N+P+K plots were significantly (P<0.05) higher than other plots except for cattle slurry plots. The CP content of barley or its mixture crops was significantly higher tor N+P+K plot (9.8%) and mixture plots with legumes (8.6~9.7%) than those of other treatments. As 450 kg Hanwoo heifers were fed diets included 70% whole crop barley or 70% mixture crops with legumes, mixture plots are capable of raising average 1.7 to 1.8 heads/ha a year. For rye or its mixture crops, annual DM, CP, and TDN yields represented 6.9~7.1, 0.5~0.6 and 4.3~4.4 ton/ha, respectively. The N+P+K plot contained 10.8% CP, which was higher (P<0.05) than all other treatments. In case of 450 kg Hanwoo heifers fed diets included 70% rye or 70% mixture crops with legumes, mixture plots can rear average 1.9 heads/ha a year. When it was considered based on crop yields and organic stock carrying capacity, applying cattle slurry to whole crop barley or rye had the comparable yields and feed values to chemical fertilizer application. Moreover, whole crop barley and rye within cattle slurry plots had a greater combination with hairy vetch and forage pea, respectively, and their mixture crops with legumes had higher crude protein and TDN yields within cattle slurry plots. In conclusion, it would be expected that mixed sowing with legumes in the application of cattle slurry to grass crops could be substituted for imported organic grains as dietary protein sources in feeding organic livestock.

• Composites Research
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• v.18 no.4
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• pp.27-34
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• 2005

Salt water spray and immersion tests were experimentally conducted for over 6 months to investigate the durability of glass fabric/phenolic composites under salt water environment. Mechanical properties such as tensile properties, flexural properties, and shear properties were evaluated and thermal analysis properties such as storage shear modulus, loss shear moduls, and tan 6 were obtained through a DMA. A change in chemical structures was analyzed through a FTIR. According to the results, mechanical properties and thermal analysis properties were sensitive to salt water environment and these properties began to degrade in increasing in exposure times. However, tensile and flexural moduli started to decrease and then slightly increase as increasing in exposure times due to plasticization and crosslinking in matrix as well as physical swelling in composites. Beyond a certain exposure times, these properties began to decrease as further increasing in exposure times. Also the shape and location of peaks in FTIR curves were insensitive to exposure times, but the intensity of peaks would be. finally we found that the durability of glass fabric/phenolic composites were affected on salt water immersion environment rather than salt water spray environment.

• Applied Chemistry for Engineering
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• v.10 no.3
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• pp.374-381
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• 1999

Poly(vinyl alcohol) (PVA) membranes crosslinked with poly(styrene-maleic anhydride) (PSMAn) were prepared, and the pervaporation characteristics of the membranes were studied for the separation of water/ethanol mixtures. The prepared PVA membranes showed that the permeation rate and separation factors were increased with increasing of PSMAn contents in the feed of 92/8 wt. % ethanol/water composition. However, when the water content in the feed composition was increased highly, the overall permeation rate was increased in the order of 2%>1%>0.5% in spite of the increase of the crosslinking contents, and the separation factor was decreased due to the higher sorbed water contents and the consequent plasticization action of membrane. Also, with respect to operating temperature, the permeation rate of the membranes obeyed the Arrhenius type. Especially, in the case of 2% crosslinked membrane, it was shown based on the pervaporation characteristics that both the permeation rate and separation factor were increased with increasing operating temperature from $30^{\circ}C$( to $50^{\circ}C$. From these results, it can be known that the hydrophilic groups introduced in the membrane by PSMAn highly affected the transport of permeants.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.1
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• pp.44-49
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• 2020

This study was conducted to investigate the possibility of replacing imported Timothy hay (TH) with domestic Italian ryegrass silage (IRGS) as a horse feed considering feed quality, nutrient digestibility and feed price. Two experimental diets (TH and IRGS) were fed to six-headed Thoroughbred (body weight, 475.7±33.3kg) of the Korea Racing Authority of Wondang Stud Farm. The 3 head animals were assigned to Control group (TH) and Treatment group (IRGS), respectively. The nutrient digestibility was determined by the total collection method. IRGS is enough for using as a horse feed because its Relative feed value(RFV) was higher than TH and its fermentation quality is suitable for horses. Although no difference was observed in nutrient digestibility, Total digestible nutrients(TDN), and Digestible energy(DE) between Control and Treatment group (p>0.05), the fact that price of IRGS was much lower (53.7~62.4%) than that of TH indicates IRGS has competitive advantage over TH as a horse forage feed. The present study indicates that IRGS can be fully replaced with TH due to its superior economic value even though the similarity of its nutrient digestibility, TDN, and DE to TH.

• Applied Chemistry for Engineering
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• v.7 no.4
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• pp.605-613
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• 1996

The permeation characteristics were investigated for pure carbon dioxide and methane through asymmetric cellulose acetate(CA) membrane, composite cellulose acetate membrane and asymmetric cellulose triacetate(CTA) membrane. In particular, the effect of operating pressure on the permeation performance was examined. And the permeation behavior for a mixture of carbon dioxide and methane ($CO_2/CH_4=57.6/42.4$) was also investigated and compared to the characteristics obtained from pure gases. The experiments were run at the range of partial pressure from 25 to 125 psig, and room temperature. The permeation behaviors of the CA composite and CTA membrane were similiar to those of the CA membrane. The permeation rates of pure carbon dioxide for CA, CA composite and CTA membrane were increased slightly with an increase in upstream partial pressure, while in the case of pure methane they were independent of upstream partial pressure. For a binary mixture of carbon dioxide and methane, abnormal permeation behaviors were observed due to the plasticization of carbon dioxide and the competition effect of each gas. The separation factor and permeation rate for CTA membrane were found to be higher than those for CA membrane, but the mechanical strength of CTA membrane was very poor. And the permeation rate for CA composite membrane was higher than that for CA membrane. Consequently, it can be said that the CA composite membrane is a strong candidate for the separation of $CH_4$ and $CO_2$.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.1
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• pp.17-23
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• 2019

This experiment was carried out to evaluate the characteristic and productivity of forage corn varieties sown at the last ten days of May at Cheonan of Korea on 2017 and 2018. Forage corn varieties sown on 24th May 2017 and $25^{th}$ May 2018 were emerged in 5th and 1st June, respectively. Silking date of forage corns was different among varieties(p<0.05). Stem length of forage corns was not different among the varieties, except Kwangpyeongok(KPA) and Nero IT. Stem diameter of forage corns was not different amaong the varieties. Outbreak rate of black streaked dwarf virus was lower than 3% in all varieties. Total digestible nutrient(TDN) yield was different among corn varieties(p<0.05), which was higher in P32P75, followed by P2088, P31N27, and KPA. The TDN yield of varieties had direct correlation with stem length, stem diameter and ear yield, respectively(p<0.01). Average of TDN in all varieties was 69.8%. These results suggested that forage corn variety with late-seeding adaptability is more important for increasing the productivity of forage corn If harvesting of winter forage crops have to be finished in the middle ten days of May in middle region of Korea.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.59-59
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• 2009

현재 CMP분야는 광역 평탄화 반도체 소자의 집적화 및 소형화가 진행됨에 따라서 CMP 공정의 중요성은 날로 성장하고 있다. 하지만 이러한 CMP공정은 불가피하게도 scratch, pit, CMP residue와 같은 defect들을 발생시키고 있으며, 점점 선폭이 작아짐에 따라, 이러한 defect들이 반도체 수율에 미치는 영향은 심각해지고 있다. Defect들 중에 특히 scratch는 반도체에 치명적인 circuit failure를 일으키게 된다. 또한 반도체 내구성과 신뢰성을 감소시키게 되고, 누전전류를 증가시키는 등 바람직하지 못한 현상들이 생기게 된다. 본 연구에서는 scratch 와 같은 deflect들을 효율적으로 검출, 분석하고, scratch를 감소시키는데 그 목적이 있다. 본 실험을 위해 8" TEOS wafer와 commercial oxide slurry 및 friction polisher (Poli-500, G&P tech., Korea)를 사용하여 CMP 공정을 진행하였으며, CMP 공정조건은 각각 80rpm/80rpm/1psi(Platen speed/Head speed/Pressure)에서 1분 동안 연마를 한 후 scratch 발생 경향을 살펴보았다. CMP 후 wafer위에 오염되어 있는 slurry residue들을 제거하기 위해 SC-1, HF 세정을 이용하여 최적화된 post-CMP 공정기술을 제안하였다. Scratch 검출 및 분석을 위해 wafer surface analyzer (Surfscan 6200, Tencor, USA)와 optical microscope (LV100D, Nicon, Japan)를 사용하였다. CMP 공정 변수들에 따른 scratch 발생정도를 비교하였으며, scratch 발생 요인들에 따른 scratch 형태 및 발생정도를 살펴보았다. 최적화된 post-CMP 세정 조건은 메가소닉과 함께 SC-1 세정을 실시하여 slurry residue들을 제거한 후, HF 세정을 실시하여 잔여 오염물들을 제거하고 검출이 용이하도록 scratch를 확장시킬 수 있도록 제안하였으며, 100%의 particle removal efficiency (PRE)를 얻을 수 있었다. 실제 CMP 공정후 post-CMP 세정 단계별 scratch 개수를 측정한 결과, SC-1 세정 후 약 220개의 scratch가 검출되었으며, 검출되지 않았던 scratch가 HF 세정 후 확장되어 드러남에 따라 약 500개의 scratch 가 검출되었다.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.19-19
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• 2012

최근 산업환경 변화에 순응하는 환경 친화적 소재를 사용하여 자동차, 선박, 철도 등 수송용 인테리어 내장재를 구성하는 기술로서, 난연성 및 기계적 물성 유지 기술, 그리고 실내 쾌적감을 부여하기 위한 감성기술 및 심미적 요소를 부여하는 디자인 기술이 가미된 복합 기능화 기술개발이 구되고 있다. 기존의 자동차용 시트 제품은 대부분 PU Foam을 시트원단에 불꽃으로 Lamination 하는 방식으로 제조되었으며, 이러한 제조 방식은 많은 공정을 거치게 되고 PU Foam을 제조하는 공정 및 불꽃으로 Lamination 하는 공정에서 많은 환경유해가스가 발생하는 등 환경적으로도 많은 문제점을 감수하면서 생산하는 방식이다. 또한 각종 원단의 표피재로 많이 사용되고 있는 PU와 PVC의 경우 제조과정에서 용제와 가소제 사용 등으로 인해 환경적으로 많은 문제점이 있으며, 이를 대체하기 위한 노력이 많은 부분에서 이루어지고 있지만, 마땅히 대체할 소재를 찾지 못하고 있는 실정이다. 본 연구에서 제안하는 실리콘수지는 기존의 PU와 PVC를 대체할 수 있는 소재로서 각광받고 있으며, 응용기술 개발을 통해 충분히 적용이 가능한 소재라고 판단된다. 본 연구에서 개발하고자 하는 기술은 난연성을 가진 실리콘 내장 표피재에 불꽃으로 Lamination하는 공정을 배제한 친환경 PUD Foam을 바로 Back Coating함으로써 일체형 고 기능 친환경 제품을 개발함으로써 친환경 복합화 기술 및 SEAT 원단과 표피재의 일체형 모듈화 공법개발을 이루고자 한다.

• Applied Chemistry for Engineering
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• v.10 no.8
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• pp.1216-1220
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• 1999

Different amounts of zinc stearate were incorporated as a plasticizer into poly(styrene-co-sodium methacrylate) ionomers prepared by bulk-suspension plymerization and neutralization with sodium hydroxide and effects of the zinc stearate on the thermal and rheological properties were investigated. It was obseved that the crystallization of zinc stearate in the ionomers were partially suppressed depending on the content of ionic moieties. It is postulated that the ionic moieties dissolved zinc stearate and suppressed crystallization of the zinc stearates. We speculated that 0.4~0.6 mole of zinc stearate was dissolved by one mole of the ionic moiety. Poly(styrene-co-sodium methacrylate) containing only the dissolved zinc stearates showed typical rheological properties of homogeneous systems in Cox-Mertz plots. However, poly(styrene-co-sodium methacrylate) containing crystallizable zinc stearates as well as dissolved ones showed typical rheological properties of heterogeneous systems.