• 제목/요약/키워드: Yield surface

검색결과 1,593건 처리시간 0.031초

Reactive Dyeing of Photografted para-Aramid Fabrics

  • Kim, Eun-Min;Jang, Jin-Ho
    • 한국염색가공학회지
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    • 제23권3호
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    • pp.155-162
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    • 2011
  • para-Aramid has limited dyeability because of its highly crystalline structure and compactness. To improve the dyeability of the para-aramid to reactive dyes of bright color in deep shade, the fabrics were photografted under continuous UV irradiation with dimethylaminopropyl methacrylamide and 4-benzoyl benzoic acid as a monomer and a hydrogen -abstractable photoinitiator respectively. A UV energy of 35J/$cm^2$ and a photoinitiator concentration of ten percent or more with respect to the monomer in the formulation was required for optimal photografting. Grafting yield increased with higher monomer application level. Surface analysis indicated significant alterations in the atomic composition of the photografted fabric surface and the fabric surface was covered with the grafted polymers. While the pristine para-aramid fabrics showed no appreciable dyeability to the ${\alpha}$-bromoacrylamide reactive dyes, the grafted para-aramid fabrics enhanced the dyeability to the reactive dyes substantially. In case of C.I. Reactive Blue 50, a K/S value of 8.7 can be obtained with the grafted para-aramid fabrics with a grafting yield of 2.3 %. Also the color fastness properties of the dyed fabrics was excellent in the conditions of washing, rubbing and light irradiation.

옥수수 섬유질로부터 검과 수용성 아라비노자일란의 수율향상을 위한 압출성형 조건의 최적화 (Optimization of Extrusion Process Conditions to Increase the Corn Fiber Gum and Soluble Arabinoxylan Yield from Corn Fiber)

  • 전수정;류기형
    • 한국식품과학회지
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    • 제47권2호
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    • pp.149-157
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    • 2015
  • 본 연구는 압출성형 된 옥수수 섬유질로부터 화학적 추출을 통해 SAX와 CFG 수율을 향상시키기 위해 반응표면분석법을 이용하여 최적의 압출성형조건을 확립하였다. 압출성형공정 조건 중 수분함량($X_1$), 스크루 회전속도($X_2$), 배럴온도($X_3$)를 독립 변수로 하고 옥수수 섬유질의 residual solid, final solution, 그리고 CFG의 수율과 각각의 SAX값을 종속 변수로 하여 화학적으로 추출 하였다. 그 결과, 수율의 경우 final solution은 EDCF가 DCF보다 낮은 경향을 보였고, residual solid와 CFG의 경우, EDCF가 DCF보다 높은 경향을 나타내었다. SAX값은 모든 조건의 EDCF가 DCF보다 높은 경향을 나타냈다. 각각의 결정된 최적의 압출성형 조건에서 분석한 결과 모든 조건에서 예측값과 결과값이 유사하여 반응표면 분석의 결과가 양호한 것으로 나타났다. 이상의 연구결과에서 반응표면 분석법이 압출성형 공정에 의한 CFG의 수율과 총 SAX값의 최적화를 위한 적절한 방법 중 하나라는 것을 보여주었다.

Statistical Optimization of Biosurfactant Production from Aspergillus niger SA1 Fermentation Process and Mathematical Modeling

  • Mansour A. Al-hazmi;Tarek A. A. Moussa;Nuha M. Alhazmi
    • Journal of Microbiology and Biotechnology
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    • 제33권9호
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    • pp.1238-1249
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    • 2023
  • In this study, we sought to investigate the production and optimization of biosurfactants by soil fungi isolated from petroleum oil-contaminated soil in Saudi Arabia. Forty-four fungal isolates were isolated from ten petroleum oil-contaminated soil samples. All isolates were identified using the internal transcribed spacer (ITS) region, and biosurfactant screening showed that thirty-nine of the isolates were positive. Aspergillus niger SA1 was the highest biosurfactant producer, demonstrating surface tension, drop collapsing, oil displacement, and an emulsification index (E24) of 35.8 mN/m, 0.55 cm, 6.7 cm, and 70%, respectively. This isolate was therefore selected for biosurfactant optimization using the Fit Group model. The biosurfactant yield was increased 1.22 times higher than in the nonoptimized medium (8.02 g/l) under conditions of pH 6, temperature 35℃, waste frying oil (5.5 g), agitation rate of 200 rpm, and an incubation period of 7 days. Model significance and fitness analysis had an RMSE score of 0.852 and a p-value of 0.0016. The biosurfactant activities were surface tension (35.8 mN/m), drop collapsing (0.7 cm), oil displacement (4.5 cm), and E24 (65.0%). The time course of biosurfactant production was a growth-associated phase. The main outputs of the mathematical model for biomass yield were Yx/s (1.18), and µmax (0.0306) for biosurfactant yield was Yp/s (1.87) and Yp/x (2.51); for waste frying oil consumption the So was 55 g/l, and Ke was 2.56. To verify the model's accuracy, percentage errors between biomass and biosurfactant yields were determined by experimental work and calculated using model equations. The average error of biomass yield was 2.68%, and the average error percentage of biosurfactant yield was 3.39%.

M-K 모델 기반의 박판금속 성형성 평가에서 물성의 영향에 대한 해석적 연구 (Analytical Study of the Effect of Material Properties on the Formability of Sheet Metals based on the M-K Model)

  • ;김석봉;허훈
    • 소성∙가공
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    • 제19권7호
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    • pp.393-398
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    • 2010
  • This paper investigates the effect of material properties on the formability of sheet metals based on the Marciniak-Kuczynski model (M-K model). The hardening behavior of the material is modeled as the Hollomon model with the strain rate effect. The yield surfaces are constructed with Hosford79 yield function. The material properties considered in this study include the R-value, the strain hardening exponent, the strain rate hardening exponent, and the crystal structure of the material. The effect of the crystal structure on formability is roughly expressed as the change of the yield surface by varying the value of the exponent in Hosford79 yield function. Results show that the R-value affects neither the magnitude nor the shape of right hand side of forming limit diagrams (FLDs). Higher strain hardening exponent and higher strain rate hardening exponent improve the formability of sheet metals because they stabilize the forming processes.

다져진 보조기층 재료의 불포화 전단강도 및 항복하중 평가 (Estimating Unsaturated Shear Strength and Yield Load of Compacted Aggregate Sub-base Materials)

  • 전혜지;박성완
    • 대한토목학회논문집
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    • 제31권4D호
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    • pp.571-576
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    • 2011
  • 일반적으로 도로구조물들은 포화상태라는 가정 하에 설계되고 있으나 실제 도로구조물의 재료인 입상지반재료는 대부분 불포화 상태에 존재하고 있다. 이러한 부분을 반영하기 위하여 본 논문에서는 다져진 입상지반재료를 대상으로 삼축압축시험과 함수특성곡선 시험 결과를 활용하여 다양한 조건에서의 불포화 전단강도를 추정하였다. 이를 바탕으로 비선형 모형을 활용한 2차원 유한요소해석을 실시하고 Mohr-Coulomb항복조건을 통하여 항복하중을 규명하였다. 또한, 입상재료의 항복하중에 대한 도로구조물 표층두께의 변화에 따른 영향을 확인하였다. 해석 결과 입상지반재료의 불포화토 이론을 고려하여 포장 혹은 비포장 도로의 지지력을 예측할 수 있음을 보여주고 있다.

전력반도체의 수율향상을 위한 최적 공정조건 결정에 관한 연구 (Process Conditions Optimizing the Yield of Power Semiconductors)

  • 고관주;김나연;김용수
    • 품질경영학회지
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    • 제47권4호
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    • pp.725-737
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    • 2019
  • Purpose: We used a data analysis method to improve semiconductor manufacturing yield. We defined and optimized important factors and applied our findings to a real-world process. The semiconductor industry is very cost-competitive; our findings are useful. Methods: We collected data on 15 independent variables and one dependent variable (yield); we removed outliers and missing values. Using SPSS Modeler ver. 18.0, we analyzed the data both continuously and discretely and identified common factors. Results: We optimized two independent variables in terms of process conditions; yield improved. We used DS Leak software to model netting and Contact CD software to model meshes. DS Leak shows smaller the better characterisrics and Contact CD shows normal the best characteristics Conclusion: Various efforts have been made to improve semiconductor manufacturing yields, and many studies have created models or analyzed various characteristics. We not only defined important factors but also showed how to control processing to improve semiconductor yield.

Numerical Implementation of Modified Coulomb-Mohr Yield Criterion for Anisotropic and Asymmetric Materials

  • Lee Myoung-Gyu;Kim Ji-Hoon;Ryou Han-Sun;Chung Kwan-Soo;Youn Jae-Ryoun;Kang Tae-Jin
    • Fibers and Polymers
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    • 제7권3호
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    • pp.276-285
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    • 2006
  • Development and numerical implementation for an elastoplastic constitutive model for anisotropic and asymmetric materials are presented in this paper. The Coulomb-Mohr yield criterion was modified to consider both the anisotropic and asymmetric properties. The modified yield criterion is an isotropic function of the principal values of a symmetric matrix which is linearly transformed from the Cauchy stress space. In addition to the constitutive equation, the numerical treatment for the singularity in the vertex region of yield surface and stress integration algorithm based on elastoplasticity were presented. In order to assess the accuracy of numerical algorithm, isoerror maps were considered. Also, extension of a strip with a circular hole was simulated and results compared with those obtained using the (smooth) Mises yield criterion to validate stress output for a complex stress state.

Growth and yield responses of rice varieties to various soil water deficit conditions under different soil types

  • Kikuta, Mayumi;Samejima, Hiroaki;Magoti, Rahab;Kimani, John M.;Yamauchi, Akira;Makihara, Daigo
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.322-322
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    • 2017
  • To avoid drought stress under rainfed upland conditions, it is important for rice to efficiently utilize water at shallow soil layers supplied by rainfall, and access to water retained in deer soil layers. The root developmental characteristics of rice, which play important role in the adaptability to drought conditions, vary depending on the variety. Moreover, water availability for plant differs depending on the soil types that have different physical properties such as water holding capacity, permeability, capillary force, penetration resistance, etc. In this study, we evaluated growth and yield responses of rice varieties to various soil water deficit conditions under three different soil types. The experiment was conducted in a plastic greenhouse at the Kenya Agricultural and Livestock Research Organization-Mwea from October 2016 to January 2017. Two upland varieties (NERICA 1 and 4) and one lowland variety (Komboka) were grown in handmade PVC pots (15.2 cm diameter and 85.0 cm height) filled with three different types of soil collected from major rice-growing areas of the country, namely black cotton (BC), red clay (RC), and sandy clay (SC). Three watering methods, 1) supplying water only from the soil surface (W1), 2) supplying water only from the bottom of the pots (W2), and 3) supplying water both from the soil surface and the bottom of pots (W3), were imposed from 40 days after sowing to maturity. Soil water content (SWC) at 20, 40, and 60 cm depths was measured regularly. At the harvesting stage, aboveground and root samples were collected to determine total dry weight (TDW), grain yield, and root length at 0-20, 20-40, 40-60, and 60-80 cm soil layers. Irrespective of the watering methods, the greatest root development was obtained in RC, while that in BC was less than other two soils. In BC, the degree of yield reduction under W1 was less than that in RC and SC, which could be attributed to the higher water holding capacity of BC. In RC, the growth and yield reduction observed in all varieties under W1 was attributed to the severe drought stress. On the other hand, under W2, SWC at the shallow soil depth in RC was maintained because of its higher capillary force compared with BC and SC. As the result, growths and yields in RC were not suppressed under W2. In SC, deep root development was not promoted by W2 irrespective of the varieties, which resulted in significant yield losses. Under W1, the rice growth and yield in SC was decreased although shallow root development was enhanced, and the stomatal conductance was maintained higher than RC. It was suspected that W1 caused nutrients leaching in SC because of its higher permeability. Under rainfed conditions, growth and yield of rice can be strongly affected by soil types because dynamics of soil water conditions change according to soil physical properties.

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반건식 세정기의 산성가스 제거성능에 관한 실험적 연구 (An Experimental Approach to Evaluate the Desulfurization Yield in Spray Drying Sorber)

  • 양현모;김상수
    • 대한기계학회논문집B
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    • 제24권4호
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    • pp.589-598
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    • 2000
  • A pilot-scale Spray Drying Sorber (SDS) system was set up to evaluate the effect of spray characteristics on the desulfurization yield. The size distribution and the Sauter Mean Diameters of slurry droplets were measured in advance using the optical size measurement system, Malvern 2600. The desulfurization yield of the drying chamber by size was measured for the conditions of inlet gas and spray injection. As a reagent, 10% limestone slurry of $Ca(OH)_2$ was treated with flue gas containing $SO_2$, and the combustion gas analyzer and gas detectors were attached to measure the $SO_2$ concentration. With a flow rate of 144 Nm3/h and a temperature range of $200{\sim}300^{\circ}C$, the experiments were performed for the Stoichiometric Ratio (SR) of 1.0 to 3.0 and droplet mean diameter of 6.5 to $34.3{\mu}m$. In case of smaller spray droplets, the desulfurization efficiency improved due to the increase of total droplet surface area, while the reduction in evaporation time reduced the contact time between the droplets and $SO_2$ gas. In some typical region of droplet diameter, this negative effect, reduction of contact time, became dominant and the desulfurization yield decreases the desulfurization yield in spite of the expansion in absorption area. These results revealed that there exists the optimal size of spray droplets for a given state, which is determined by the compromise between the total surface area of slurry droplets and the evaporation time of droplets. The measurements also indicated that the inlet temperature of flue gas changes the optimal injection condition by varying the driving force for evaporation. The results confirm that the effect of the evaporation time of slurry droplets should be considered in analyzing the desulfurization yield as well as the total surface area, for it is a significant aspect of the correlation with the capabilities of $SO_2$ absorption in wet droplets. In conclusion, the optimal condition of spray can be determined based on these results, which might be applied to design or scale-up of SDS system.

고랭지 밭의 비점오염부하 저감을 위한 지표피복재와 토양개량제의 효과 (Effects of Surface Cover and Soil Amendments on the NPS load Reduction from Alpine Fields)

  • 원철희;신민환;이수인;금동혁;임경재;최중대
    • 한국농공학회논문집
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    • 제56권3호
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    • pp.47-53
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    • 2014
  • We investigated the effect of straw mat cover and soil amendments on the reduction of runoff, non-point source pollution load and yield of a Chinese cabbage from alpine fields. Two plots on sandy loam soil were prepared. Experimental treatments were control and rice straw mat cover (3,300 kg/ha)+Polyacrylamide (PAM) (5 kg/ha)+Gypsum (1 ton/ha) (SPG). A variety of Chinese cabbage was cultivated and runoff was monitored during a growing season in 2012. Monitoring was conducted to seven times. Runoff rate of SPG plot was lower than those of control plot. The reduction rate of runoff from SPG plot was 29.4 % compared to control plot. The reduction rate of suspended solids (SS), total nitrogen (TN) and total phosphorus (TP) load of SPG plot was 86.5 %, 34.7 % and 39.1 %, respectively. Yield of a Chinese cabbage from SPG plot (39,646 kg/ha) was greater than that of control plots (28,482 kg/ha). It was concluded that the use of SPG on soil surface could not only reduce the NPS pollution loads in receiving waters but also help increase the crop yield.