• Title/Summary/Keyword: optimization of production

Search Result 1,617, Processing Time 0.026 seconds

Low temperature plasma deposition of microcrystalline silicon thin films for active matrix displays: opportunities and challenges

  • Cabarrocas, Pere Roca I;Abramov, Alexey;Pham, Nans;Djeridane, Yassine;Moustapha, Oumkelthoum;Bonnassieux, Yvan;Girotra, Kunal;Chen, Hong;Park, Seung-Kyu;Park, Kyong-Tae;Huh, Jong-Moo;Choi, Joon-Hoo;Kim, Chi-Woo;Lee, Jin-Seok;Souk, Jun-H.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2008.10a
    • /
    • pp.107-108
    • /
    • 2008
  • The spectacular development of AMLCDs, been made possible by a-Si:H technology, still faces two major drawbacks due to the intrinsic structure of a-Si:H, namely a low mobility and most important a shift of the transfer characteristics of the TFTs when submitted to bias stress. This has lead to strong research in the crystallization of a-Si:H films by laser and furnace annealing to produce polycrystalline silicon TFTs. While these devices show improved mobility and stability, they suffer from uniformity over large areas and increased cost. In the last decade we have focused on microcrystalline silicon (${\mu}c$-Si:H) for bottom gate TFTs, which can hopefully meet all the requirements for mass production of large area AMOLED displays [1,2]. In this presentation we will focus on the transfer of a deposition process based on the use of $SiF_4$-Ar-$H_2$ mixtures from a small area research laboratory reactor into an industrial gen 1 AKT reactor. We will first discuss on the optimization of the process conditions leading to fully crystallized films without any amorphous incubation layer, suitable for bottom gate TFTS, as well as on the use of plasma diagnostics to increase the deposition rate up to 0.5 nm/s [3]. The use of silicon nanocrystals appears as an elegant way to circumvent the opposite requirements of a high deposition rate and a fully crystallized interface [4]. The optimized process conditions are transferred to large area substrates in an industrial environment, on which some process adjustment was required to reproduce the material properties achieved in the laboratory scale reactor. For optimized process conditions, the homogeneity of the optical and electronic properties of the ${\mu}c$-Si:H films deposited on $300{\times}400\;mm$ substrates was checked by a set of complementary techniques. Spectroscopic ellipsometry, Raman spectroscopy, dark conductivity, time resolved microwave conductivity and hydrogen evolution measurements allowed demonstrating an excellent homogeneity in the structure and transport properties of the films. On the basis of these results, optimized process conditions were applied to TFTs, for which both bottom gate and top gate structures were studied aiming to achieve characteristics suitable for driving AMOLED displays. Results on the homogeneity of the TFT characteristics over the large area substrates and stability will be presented, as well as their application as a backplane for an AMOLED display.

  • PDF

Improvement of Energy Efficiency of Plants Factory by Arranging Air Circulation Fan and Air Flow Control Based on CFD (CFD 기반의 순환 팬 배치 및 유속조절에 의한 식물공장의 에너지 효율 향상)

  • Moon, Seung-Mi;Kwon, Sook-Youn;Lim, Jae-Hyun
    • Journal of Internet Computing and Services
    • /
    • v.16 no.1
    • /
    • pp.57-65
    • /
    • 2015
  • As information technology fusion is accelerated, the researches to improve the quality and productivity of crops inside a plant factory actively progress. Advanced growth environment management technology that can provide thermal environment and air flow suited to the growth of crops and considering the characteristics inside a facility is necessary to maximize productivity inside a plant factory. Currently running plant factories are designed to rely on experience or personal judgment; hence, design and operation technology specific to plant factories are not established, inherently producing problems such as uneven crop production due to the deviation of temperature and air flow and additional increases in energy consumption after prolonged cultivation. The optimization process has to be set up in advance for the arrangement of air flow devices and operation technology using computational fluid dynamics (CFD) during the design stage of a facility for plant factories to resolve the problems. In this study, the optimum arrangement and air flow of air circulation fans were investigated to save energy while minimizing temperature deviation at each point inside a plant factory using CFD. The condition for simulation was categorized into a total of 12 types according to installation location, quantity, and air flow changes in air circulation fans. Also, the variables of boundary conditions for simulation were set in the same level. The analysis results for each case showed that an average temperature of 296.33K matching with a set temperature and average air flow velocity of 0.51m/s suiting plant growth were well-maintained under Case 4 condition wherein two sets of air circulation fans were installed at the upper part of plant cultivation beds. Further, control of air circulation fan set under Case D yielded the most excellent results from Case D-3 conditions wherein air velocity at the outlet was adjusted to 2.9m/s.

Establishment of tissue culture and acclimatization method for in vitro mass propagation of Echeveria laui and Echeveria elegans (에케베리아 라우이(Echeveria laui)와 엘레강스(Echeveria elegans)의 대량증식을 위한 조직배양 및 순화 조건 확립)

  • Kim, Youn Hee;Lee, Gee Young;Kim, Hye Hyeong;Lee, Jae Hong;Jung, Jae Hong;Lee, Sang Deok
    • Journal of Plant Biotechnology
    • /
    • v.46 no.1
    • /
    • pp.22-31
    • /
    • 2019
  • The objective of this study was to investigate the suitable parts for callus induction and optimal concentrations of growth regulators contained in the medium affecting shooting and rooting Echeveria laui and Echeveria elegans for in vitro mass production. To determine the suitable plant parts for callus induction, the leaves were divided into upper, medium and bottom parts and cultured on MS medium at different concentrations with $0{\sim}2mgL^{-1}\;NAA$ and $0{\sim}4 mgL^{-1}BA$. The upper and middle parts of leaves both showed 100% callus formation rate with $NAA\;1\;mgL^{-1}$ and $BA\;1\;mgL^{-1}$ treatment in E. laui. The middle parts of leaves showed 83.3% callus formation rate at $NAA\;2\;mgL^{-1}$ and BA 4 mgL-1 treatment in E. elegans. The shoot induction rate from callus was highest at $NAA\;0.1\;mgL^{-1}$ and $BA\;3\;mgL^{-1}$ treatment in E. laui and $NAA\;0.3\;mgL^{-1}$ in E. elegans. In addition, the number of shoots formation was 10.4 shoots high in $NAA\;1\;mgL^{-1}$ and $BA\;1\;mgL^{-1}$ treatment in E. laui and 12.0 shoots in most effective $NAA\;1\;mgL^{-1}$ and $BA\;0.1\;mgL^{-1}$ treatment in E. elegans. In the case of acclimatization of regenerated plant, growth characteristics did not show any significant difference (35 ~ 55%) shading with respect to the different ratio of substrate mixture, and it was determined that would be appropriate considered plant height and appearance preference of E. laui and E. elegans. It was established that the optimization of culture condition was responsible for the mass propagation in vitro cultures of E. laui and E. elegans.

The Fermentative Characteristics of Cheonggukjang Prepared by Starter Culture of Bacillus spp. with Fibrinolytic Activity (혈전용해활성이 우수한 Bacillus spp. 스타터를 이용한 청국장의 발효특성)

  • Hwang, Jong-Hyun
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.39 no.12
    • /
    • pp.1832-1838
    • /
    • 2010
  • The objective of this study was to improve the flavor of Cheonggukjang prepared by the culture optimization of starter with the fibrinolytic activity. After 25 strains isolated from the commercial Cheonggukjang and Doenjang in different regions were compared, 7 Bacillus strains with proteolytic and slime-producing activities were selected. When the fibrin plate method for fibrinolytic activity was applied, CJJN-4 and 5 showed the higher activity in tripticase soy broth (TSB). All Cheonggukjang prepared with CJJN-4 and 5 also had the fibrinolytic activity, regardless of culture temperature or time. Especially, Cheonggukjang prepared at $40^{\circ}C$ showed higher activity than $45^{\circ}C$, and Cheonggukjang prepared with CJJN-4 for 48 hr at $40^{\circ}C$ showed the highest fibrinolytic activity. Although there was no significant difference in pH of Cheonggukjang prepared with CJJN-4 or 5 during 72 hr at $40^{\circ}C$, Cheonggukjang prepared with CJJN-4 at $45^{\circ}C$ had lower pH until 60 hr than $40^{\circ}C$ or CJJN-5. The total amino type nitrogen contents of Cheonggukjang were 1,139.6 (CJJN-4) and 1,027.6 mg% (CJJN-5) for 72 hr at $40^{\circ}C$, and their producing rates were also higher at $40^{\circ}C$ fermentation than $45^{\circ}C$. Meanwhile, the contents of ammonia type nitrogen induced unpleasant flavor were lower in Cheonggukjang with CJJN-4 and 5 at $40^{\circ}C$ than CJJN-5 at $45^{\circ}C$. Therefore, Cheonggukjang fermented with CJJN-4 starter at $40^{\circ}C$ had the improved flavor, such as change of amino or ammonia type nitrogen production, and higher fibrinolytic activity.

In vitro mass propagation and acclimatization of Haworthia truncata (하월시아 옥선(Haworthia truncata)의 기내 대량 증식 및 순화 조건 구명)

  • Kim, Youn Hee;Lee, Gee Young;Kim, Hye Hyeong;Lee, Jae Hong;Jung, Jae Hong;Lee, Sang Deok
    • Journal of Plant Biotechnology
    • /
    • v.46 no.2
    • /
    • pp.127-135
    • /
    • 2019
  • The purpose of this study was to investigate suitable parts for callus induction and optimal concentrations of growth regulators, contained in the medium affecting shoot and rooting for in vitro mass production of Haworthia truncata. Leaves and flower bud showed 100% callus formation rate at NAA $1{\sim}2mgL^{-1}$ treatment, and NAA $1mgL^{-1}$ + TDZ $2mgL^{-1}$ treatment. The flower stalk showed 75% callus formation rate, at NAA $2mgL^{-1}$ + TDZ $2mgL^{-1}$ treatment in H. truncata. While the rate of callus formation was high in leaves and flower bud, leaves were the most efficient in obtaining most culture parts. Shoot induction rate from callus was highest, at NAA $0.1mgL^{-1}$ treatment in H. truncata. Additionally, the number of shoots formation was 66.3 shoots high, in NAA $1mgL^{-1}$ + BA $0.1mgL^{-1}$ treatment in H. truncata. In the case of acclimatization of regenerated plant, growth characteristics did not show significant difference (95%) shading with respect to the different ratio of substrate mixture, and it was determined that would be appropriate, considering plant height and appearance preference of H. truncata. It was established that optimization of culture condition, was responsible for mass propagation in vitro cultures of H. truncata.

Optimization of Separation Process of Bioflavonoids and Dietary Fibers from Tangerine Peels using Hollow Fiber Membrane (중공사 막을 이용한 감귤 과피 bioflavonoids 분리 및 식이 섬유 회수 공정 최적화)

  • Lee, Eun-Young;Woo, Gun-Jo
    • Korean Journal of Food Science and Technology
    • /
    • v.30 no.1
    • /
    • pp.151-160
    • /
    • 1998
  • Tangerine peel is mostly discarded as waste in citrus processing. However, tangerine peel contains besides dietary fibers bioflavonoids such as naringin and hesperidin which act as antimicrobials and blood pressure depressants, respectively. A continuous membrane separation process was optimized for the production of bioflavonoids relative to feed flow rate, transmembrane pressure, temperature, and pH. The tangerine peel was blended with 7.5 times water volume and the extract was prefiltered through a prefiltration system. The prefiltered extract was ultrafiltered in a hollow fiber membrane system. The flux and feed flow rate didn't show any apparent correlation, but we could observe a mass-transfer controlled region of over 8 psi. When temperature increased from $9^{\circ}C\;to\;25^{\circ}C$, the flux increased about $10\;liters/m^2/min\;(LMH)$ but between $25^{\circ}C\;and\;33^{\circ}C$, the flux increased only 2 LMH. At every transmembrane pressure, the flux of pH 4.8 was the most highest and the flux at pH 3.0 was lower than that of pH 6.0, 7.0, or 9.0. Therefore, the optimum operating conditions were 49.3 L/hr. 10 psi, $25^{\circ}C$, and pH 4.8. Under the optimum conditions, the flux gradually decreased and finally reached a steady-state after 1 hr 50 min. The amount of dietary fibers in 1.0 g retentate in each separation step was analyzed and bioflavonoids concentration in each permeate was measured. The contents of total dietary fiber in the 170 mesh retentate and soluble dietary fiber in the prefiltered retentate were the highest. Naringin and hesperidin concentration in the permeate were $0.45{\sim}0.65\;mg/g\;and\;5.15{\sim}6.86\;mg/g$ respectively, being $15{\sim}22$ times and $79{\sim}93$ times higher than those in the tangerine peel. Therefore, it can be said that PM 10 hollow fiber membrane separation system may be a very effective method for the recovery of bioflavonoids from tangerine peel.

  • PDF

Economic Impact of HEMOS-Cloud Services for M&S Support (M&S 지원을 위한 HEMOS-Cloud 서비스의 경제적 효과)

  • Jung, Dae Yong;Seo, Dong Woo;Hwang, Jae Soon;Park, Sung Uk;Kim, Myung Il
    • KIPS Transactions on Computer and Communication Systems
    • /
    • v.10 no.10
    • /
    • pp.261-268
    • /
    • 2021
  • Cloud computing is a computing paradigm in which users can utilize computing resources in a pay-as-you-go manner. In a cloud system, resources can be dynamically scaled up and down to the user's on-demand so that the total cost of ownership can be reduced. The Modeling and Simulation (M&S) technology is a renowned simulation-based method to obtain engineering analysis and results through CAE software without actual experimental action. In general, M&S technology is utilized in Finite Element Analysis (FEA), Computational Fluid Dynamics (CFD), Multibody dynamics (MBD), and optimization fields. The work procedure through M&S is divided into pre-processing, analysis, and post-processing steps. The pre/post-processing are GPU-intensive job that consists of 3D modeling jobs via CAE software, whereas analysis is CPU or GPU intensive. Because a general-purpose desktop needs plenty of time to analyze complicated 3D models, CAE software requires a high-end CPU and GPU-based workstation that can work fluently. In other words, for executing M&S, it is absolutely required to utilize high-performance computing resources. To mitigate the cost issue from equipping such tremendous computing resources, we propose HEMOS-Cloud service, an integrated cloud and cluster computing environment. The HEMOS-Cloud service provides CAE software and computing resources to users who want to experience M&S in business sectors or academics. In this paper, the economic ripple effect of HEMOS-Cloud service was analyzed by using industry-related analysis. The estimated results of using the experts-guided coefficients are the production inducement effect of KRW 7.4 billion, the value-added effect of KRW 4.1 billion, and the employment-inducing effect of 50 persons per KRW 1 billion.