• 제목/요약/키워드: Adding-on

검색결과 6,309건 처리시간 0.037초

강섬유가 고강도 SFRC의 압축강도에 미치는 영향 (the Effect of Steel Fiber on the Compressive Strength of High Strength Steel Fiber Reinforced Cementitious Composites)

  • 강수태;박정준;고경택;김성욱;이장화
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
    • /
    • pp.308-311
    • /
    • 2004
  • Many researchers have reported that adding steel fiber to concrete improved its tensile and flexural strength significantly, but relatively few studies have been made on the compressive behavior of SFRC(steel fiber reinforced concrete). It is still less in case of high strength SFRC. The main objective of this research is to examine the effect of adding steel fiber on the compressive strength of high strength SFRC using fiber reinforcing index$(RI,\;V_f(l/d))$. It was found from the study that compressive strength was noticeably increased in proportion to RI.

  • PDF

건조된 콘크리트 재료의 포장화에 관한 기초적 연구 -가수율에 따른 콘크리트의 기초물성을 중심으로- (A Fundamental Study on Method of Packaged Dry Combined Materials for Concrete - based on physical properties of concrete according to adding-water ratio -)

  • 한다희;황병준;김제섭;박희곤;이영도;정상진
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 2003년도 가을 학술발표회 논문집
    • /
    • pp.493-496
    • /
    • 2003
  • Most concrete is recently made of an aggregate which is properly absorbed, and carried in it in order to do capability at every fields. We have been close to demand new capability of high flowing and enduring for specific concretes. That is difficult to cope with claiming the efficiency on deterioration from lack of a high quality aggregate. Therefore, for solving the problems we apply to a packing method for using dried materials. That is to say it is a kind of making into an instant. In this study, There is a purpose to present fundamental data, comparing and analyzing a phenomenon about aggregate absorption following the rate of adding water, for using existing materials.

  • PDF

CV흑연생성에 미치는 인(P) 및 보론(B) 첨가의 영향 (The Effects of Phosphorus and Boron Additions on the Formation of Compacted Vermicular Graphite Structure)

  • 박흥일;김명호;김영홍
    • 한국주조공학회지
    • /
    • 제9권5호
    • /
    • pp.389-395
    • /
    • 1989
  • The effects of phosphorus and boron additions and isothermal holding time on the residual magnesium and sulfur content, and on the resultant graphite structure of cast irons were investigated. The effective recovery ratio of magnesium showed that adding phosphorus to the melt retarded the fading rate of magnesium but adding boron accelerated it. However, the residual sulfur content was found to be decreased with isothermal holding time at the begining, and then to be increased again with holding time by resulfurization. The Mg-Equivalent for producing compacted vermicular graphite structure was found to be increased with the addition of phosphorus, whereas to be decreased with the addition of boron.

  • PDF

Effect of zinc and calcium on the intracelularly uptake of cadimium and growth of escherichia coli

  • Hong, Hyo-Bong;Brown, Lewis R.;Kim, Jong-Kyu
    • Journal of Microbiology
    • /
    • 제33권4호
    • /
    • pp.302-306
    • /
    • 1995
  • E. coli was tested for their ability to uptake cadmium intracellularly, and the effect of zinc and calcium on cadmium toxicity to E. coli was observed. In addition, the effect of zinc and calcium on the uptake of cadimium was also studied. This study showed that living E. coli cells took up more cadmium than the dead cells. E. coli in the log phase uptake cadimiumm more actively than E. coli in the stationary phase. These results suggested that there may be metabolic reactions or compounds which encourage the uptake of cadimium. This study also showed that cadimium was sequestered by cell components of which molecular weight is about 30,000. Adding of zinc and calcium chloride reduced cadmium toxicity in E. coli and encouraged intracellular uptake by E coli. However adding of heavy metal solutions helped the microorganisms to adsorb more cadmium. Extremely high or low concentrations of zinc, however, did not affect cell viability.

  • PDF

초세립 미립자로 구성된 고성능 SFRC에서 강섬유의 혼입에 따른 인장강도의 변화 (the Effect of Steel Fiber on the Tensile Strength of the High Performance Steel Fiber Reinforced Cementitious Composites)

  • 강수태;고경택;류금성;김성욱;이장화
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
    • /
    • pp.573-576
    • /
    • 2004
  • High performance SFRC composed of mira-sized ultra fine particles is characterized by high strength, high ductility and excellent durability. therefore many researches about materials based on new composition like this are performed recently. many researchers have reported that adding steel fiber to concrete improved its tensile and flexural strength significantly. the main objective of this research is to examine the effect of adding steel fiber on the tensile strength of high performance SFRC. variables considered in this study are w/c ratio and fiber volume fraction.

  • PDF

신경망을 이용한 Liner Track Cart Double Inverted Pendulum의 최적제어에 관한 연구 (The study on the Optimal Control of Linear Track Cart Double Inverted Pendulum using neural network)

  • 金成柱;李宰炫;李尙培
    • 한국지능시스템학회:학술대회논문집
    • /
    • 한국퍼지및지능시스템학회 1996년도 추계학술대회 학술발표 논문집
    • /
    • pp.227-233
    • /
    • 1996
  • The Inverted Pendulum has been one of most popular nonlinear dynamic systems for the exploration of control techniques. This paper presents a new linear optimal control techniques and nonlinear neural network learning methods. The multiayered neural networks are used to add nonlinear effects on the linear optimal regulator(LQR). The new regulator can compensate nonlinear system uncertainties that are not considered in the LQR design, and can tolerated a wider range of uncertainties than the LQR alone. The new regulator has two neural networks for modeling and control. The neural network for modeling is used to obtain a more accurate model than the given mathematical equations. The neural network for control is used to overcome deficiencies by adding corrections to the linear coefficients of the LQR and by adding nonlinear effects on the LQR. Computer simulations are performed to show the applicability and a more robust regulator than the LQR alone.

  • PDF

홍국 발효액종이 식빵반죽의 레올로지 특성에 미치는 영향 (Effects of Liquid Broth Cultured with Red Koji on the Rheological Properties of White Pan Bread Dough)

  • 김영은;백현동;김수영;이정훈;이시경
    • 한국식품과학회지
    • /
    • 제43권2호
    • /
    • pp.235-239
    • /
    • 2011
  • 홍국 배아미 5%와 10% 벌꿀용액으로 제조한 홍국 발효액종을 10-40% 첨가하여 밀가루 반죽의 레올로지 특성으로 falling number, RVA(rapid visco analyzer), farinograph, alveograph 등을 분석하였다. 홍국 발효액종 첨가량이 증가할수록 falling number 값이 낮아졌으며 10% 첨가시 $363{\pm}7.8s$, 20% 첨가시 $318{\pm}2.1s$이었다. 호화도 특성에서 홍국 발효액종 첨가량이 증가할수록 초기점도 온도와 breakdown은 상승하였고, 최고점도와 set-back값은 낮아졌다. Farinograph에서 대조구와 시험구간에 흡수율은 64.3-65.0%로 유의적 차이가 없었으나 반죽형성시간은 발효액종의 첨가량이 증가할수록 빨라졌고, 안정도는 저하되어 20% 첨가시는 9.3 min, 40% 첨가시는 3.0 min이었으며 약화도도 빨라졌다. Alveograph에서 $P_{max}(mm)$는 대조구가 158.0 mm이었으나 발효액종 첨가량이 많을수록 증가하여 40% 첨가시 190.0 mm이었다. 그러나 L, G, W 등의 값은 낮아졌다. 이상의 실험으로 홍국 발효액종을 20% 첨가까지는 반죽의 레올로지 특성인 제빵적성에 영향이 적어 빵 제조가 가능한 것으로 나타났다.

다시마 추출물이 요구르트 품질에 미치는 영향 (The Effect on the Quality of Yogurt Added Water Extracted from Sea Tangle)

  • 정은자;방병호
    • 한국식품영양학회지
    • /
    • 제16권1호
    • /
    • pp.66-71
    • /
    • 2003
  • 요구르트의 기능성을 증가시키고 동시에 요구르트의 안정성을 높일 목적으로 다시마 열수 추출액으로부터 요구르트를 제조하여 그 품질의 특성을 조사하였다. 실험구 중 0.5% 다시마 열수 추출액으로 제조한 요구르트의 적정산도가 1.89%로, 다시마 열수 추출액 무첨가구의 적정산도 1.53%보다 높은 것으로 나타났으며, 젖산균의 생육은 다시마 열수 추출액으로 촉진되어 무첨가구의 4.4$\times$$10^{8}$ CFU/$m\ell$보다 0.5%다시마 열수 추출액 첨가구가 1.4$\times$$10^{9}$ CFU/$m\ell$로 가장 높았다. 다시마 요구르트의 점도는 0.5%의 다시마에서 25 cps로, 무첨가구의 22 cps보다 높았으나 1.0% 다시마구에서는 무첨가구의 점도와 비슷한 21.5 cps로 나타났다. 7$^{\circ}C$에서 15일간의 저장시 다시마 요구르트는 pH, 산 생성 및 생균수에 거의 변화가 없어 우수한 것으로 나타났다. 커드의 침전은 0.5% 다시마 열수 추출액으로 다소 억제시킬 수 있었으며, 관능검사에서 무첨가구에 비해 1%다시마 첨가구를 가장 선호하는 것으로 나타났다.

Protease (Subtilisin Carlsberg) 가 혈액 단백질 오구의 제거에 미치는 영향(II) -헤모글로빈 오구포의 세척성- (Effect of Pretense (Subtilisin Carlsberg) on the Removal of Blood Protein Soil (II) -The Detergency of Hemoglobin from Cotton Fabics-)

  • 이정숙;김성연
    • 한국의류학회지
    • /
    • 제20권4호
    • /
    • pp.655-666
    • /
    • 1996
  • The effect of protease (subtilisin Carlsberg) on the removal of hemoglobin as protein soil was studied. The relation between the renloval and the hydrolysis of hemoglobin by subtilisin Carlsberg was discussed. The soiled babric was prepared by spotting of hemoglobin solution evenly on the cotton fabric and was denatured by steaming. The soiled fabric was washed by using Terg-0-Tometer at various conditions. The removal efficiency was evaluated by analysis of protein on the fabrics before and after washing by means of copper-Folin method. 1. The removal of hemoglobin was increased in proportion to increasing of the enzyme concentration up to a certain point, but it began to decrease above the point. 2. The hemoglobin was removed effectively by adding of subtilisin Carlsberg, and more effectively removed by adding of AOS in the enzyme solution. 3. The removal of hemoglobin deviated from the first order reaction in detergency. 4. The renloval of hemoglobin was highest at $50^{\circ}C$ in detergency, Even at low temperature the removal efficiency of enzyme was relatively higher compared with the hydrolysis of hemoglobin by the enzyme. However the removal of hemoglobin was apparently decreased with the increase of temperature over $60^{\circ}C$. 5. The removal of hemoglobin was relatively high at pH 7.0~8.0 and increased continuously with the increase of pH in detergency 6. In detergency, the removal mechanism of hemoglobin by subtilisin Carlsberg could be explained as follows: Fisrt of all, the enzyme hydrolyzed hemoglobin substrates partially by forming E-S complex at the surface of hemoglobin on the cotton fiber, and decomposed cooperative binding of hemoglobin. Subsequently, the fragments of hemoglobin were easily removed by washing. According as the enzyme penetrated to inner part of hemoglobin gradually, the hemoglobin on the cotton fiber was effectively removed by the repetition of these process. The removal of hemoglobin was more effectively increased by adding both the enzyme and AOS in the washing solution. Therefore, it was regarded that AOS molecules were adsorbed at the hydrophobic surface of denatured hemoglobin, subsequently, decomposed more effectively cooperative binding of hemoglobin, and the fragments of hemoglobin were removed more efficiently by means of the interfacial reaction of AOS.

  • PDF

Effect of Supplementary Dietary L-carnitine and Yeast Chromium on Lipid Metabolism of Laying Hens

  • Du, Rong;Qin, Jian;Wang, Jundong;Pang, Quanhai;Zhang, Chunshan;Jiang, Junfang
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제18권2호
    • /
    • pp.235-240
    • /
    • 2005
  • Two hundred and eighty-eight 21-week-old Hyline Brown laying hens were randomly allotted to 9 treatments, 32 birds for each treatment. A 3${\times}$3 (chromium${\times}$L-carnitine) factorial experiment was designed to investigate the single and interactive effects of adding yeast chromium (0, 400 and 600 ${\mu}g/kg$) and L-carnitine (0, 50 and 100 mg/kg) to corn-soybean diets on lipid metabolism of laying hens for 7 weeks. The results showed that 600 ${\mu}g/kg$ chromium or 100 mg/kg L-carnitine had significant effects on most indices of lipid metabolism (p<0.05 or 0.01). There were significant interactions on the concentration of liver triglycerides, egg yolk cholesterol, abdominal fat percentage between chromium and L-carnitine (p=0.0003-0.0500). Adding 400 ${\mu}g/kg$ chromium and 100 mg/kg Lcarnitine simultaneously was the best for reducing egg yolk cholesterol and adding 400 ${\mu}g/kg$ chromium and 50 mg/kg L-carnitine at the same time was the best for reducing abdominal fat percentage. There was no side effect on production performance of laying hens while chromium or (and) L-carnitine reduced liver lipid, abdominal fat and egg yolk cholesterol.