• 제목/요약/키워드: Various reducing conditions

검색결과 510건 처리시간 0.03초

Extractive fermentation of Monascus purpureus promotes the production of oxidized congeners of the pigment azaphilone

  • Lim, Yoon Ji;Lee, Doh Won;Park, Si-Hyung;Kwon, Hyung-Jin
    • Journal of Applied Biological Chemistry
    • /
    • 제61권4호
    • /
    • pp.327-334
    • /
    • 2018
  • Monascus is a source of food colorant with high productivity of the pigment azaphilone. Monascus azaphilone (MAz) is biosynthesized through a single non-reducing polyketide pathway, the major components of which are ankaflavin (1), monascin (2), rubropunctatin (3) and monascorubrin (4); valuable biological activities have been reported for these compounds. Thus, various culture conditions were explored to reduce the cost of culture ingredients, enhance productivity and modulate compound composition. In the present study, we examined an extractive fermentation (EF) method with Diaion HP-20 resin (HP20) in direct comparison to a previously explored method involving Triton X-100 (TX100) to explore the modulated production of the major MAzs. We employed wild-type Monascus purpureus as well as two derivative recombinant strains (${\Delta}mppG$ and ${\Delta}mppE$) that are known to have differential MAz profiles as that of the wild-type strain. The HP20 resin was capable of modulating the MAz profile in favor of orange MAzs 3 and 4, oxidized congeners in this class, as was TX100-a phenomenon not previously observed for TX100 EF with Monascus anka. These finding substantiate that HP20 can be employed for the selective production of oxidized MAz and for diversifying the culture conditions used for Az production.

인식 및 이용실태에 기반한 학교 실내 녹색공간의 효용성 분석 -수도권 중·고등학교를 중심으로- (Analysis of the Recognition and Usage of Indoor Green Space in Middle and High Schools )

  • 박준호;이주영
    • 한국환경과학회지
    • /
    • 제32권8호
    • /
    • pp.573-583
    • /
    • 2023
  • This study was conducted to verify the effectiveness of improving indoor environmental awareness, relieving stress, and improving learning efficiency in school indoor green space, and suggest desirable ways to develop indoor green space in the future. As part of the study, a survey was conducted among 225 individuals across six schools in a metropolitan area with garden and panel-type indoor gardens inside the school building. The survey comprised the current status and use of indoor green spaces, the perception of indoor green spaces, improvement measures in indoor green spaces, and basic properties. Semantic Differential (SD) was used to investigate the impression of school indoor spaces. Resultantly, the more frequent the use of green spaces in the school, the more they feel the positive effects of indoor green spaces, such as improving the school's indoor environment, reducing stress, and improving learning efficiency. In addition, it appears that the more frequent contact with the natural environment, the more they feel the positive effects provided by indoor green space at school. Therefore, it is suggested that educational conditions must be improved by revitalizing various green welfare, including indoor green areas, at the school level.

The Impact of Manual Therapy on Pain Catastrophizing in Chronic Pain Conditions: A Systematic Review and Meta-analysis

  • Hyunjoong Kim;Seungwon Lee
    • Physical Therapy Rehabilitation Science
    • /
    • 제12권2호
    • /
    • pp.177-184
    • /
    • 2023
  • Objective: Manual therapy is a commonly utilized approach in managing chronic pain, but its specific impact on pain catastrophizing remains uncertain. The objective of this systematic review and meta-analysis was to examine the effects of manual therapy on pain catastrophizing in individuals with chronic pain. Design: A systematic review and meta-analysis Methods: A comprehensive search was conducted in electronic databases to identify relevant studies published from 2014 onwards. Studies that evaluated the impact of manual therapy on pain catastrophizing in individuals with chronic pain were incorporated. The risk of bias in the selected studies was evaluated using the Cochrane tool for risk of bias in qualitative analysis. For the quantitative analysis, RevMan 5.4 software was utilized, employing a random-effects model as the analysis model. The effect measure used in the analysis was the standardized mean difference (SMD). Results: In total, 26 studies were collected, and following the screening process, three of them were incorporated into the final analysis. The included studies involved a total of 153 patients with chronic pain. The interventions comprised various manual therapy techniques targeting different areas of the body. Pain catastrophizing and pain intensity were the primary outcomes of interest. The meta-analysis revealed a significant reduction in pain catastrophizing scores following manual therapy intervention compared to control conditions (SMD = -0.91, 95% CI: -1.25 to -0.58). However, heterogeneity between the studies was observed. Conclusions: Despite the limited quantity and heterogeneity of studies, it has been demonstrated that manual therapy intervention is effective in reducing pain catastrophizing in individuals with chronic pain.

거리 기반 적응형 임계값을 활용한 강건한 3차원 물체 탐지 (Robust 3D Object Detection through Distance based Adaptive Thresholding)

  • 이은호;정민우;김종호;이경수;김아영
    • 로봇학회논문지
    • /
    • 제19권1호
    • /
    • pp.106-116
    • /
    • 2024
  • Ensuring robust 3D object detection is a core challenge for autonomous driving systems operating in urban environments. To tackle this issue, various 3D representation, including point cloud, voxels, and pillars, have been widely adopted, making use of LiDAR, Camera, and Radar sensors. These representations improved 3D object detection performance, but real-world urban scenarios with unexpected situations can still lead to numerous false positives, posing a challenge for robust 3D models. This paper presents a post-processing algorithm that dynamically adjusts object detection thresholds based on the distance from the ego-vehicle. While conventional perception algorithms typically employ a single threshold in post-processing, 3D models perform well in detecting nearby objects but may exhibit suboptimal performance for distant ones. The proposed algorithm tackles this issue by employing adaptive thresholds based on the distance from the ego-vehicle, minimizing false negatives and reducing false positives in the 3D model. The results show performance enhancements in the 3D model across a range of scenarios, encompassing not only typical urban road conditions but also scenarios involving adverse weather conditions.

PMSG 풍력 터빈의 특성을 고려한 발전 시스템 시뮬레이션 (PMSG Wind Turbine Simulation under the consideration of real characteristics)

  • 심준보;김명호;박기현;한경섭
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 한국신재생에너지학회 2010년도 추계학술대회 초록집
    • /
    • pp.182.2-182.2
    • /
    • 2010
  • A various algorism has been studied to extract possibly every energy from a wind turbine in conjunction with the increase of concern about wind power system. In order to verify these control algorism, it is essential to make the most similar conditions to the real wind turbine's environment. Therefore, using separately excited DC motor a wind turbine the most similar to the real turbine is simulated. Tower shadow effect and Wind shear effect are considered as well as inertia emulation. For the control of Back-to-Back Converter Vector current control methods and space vector pulse width modulation are used and for reducing THD of grid current LCL filter is considered. This simulation results verified the energy produced by wind all flows into the utility under the consideration of the characteristics of a wind turbine. The result of this paper is expected to be used as a basic material for analyzing the characteristics of the wind turbine generator.

  • PDF

Classical Tamil Speech Enhancement with Modified Threshold Function using Wavelets

  • Indra., J;Kasthuri., N;Navaneetha Krishnan., S
    • Journal of Electrical Engineering and Technology
    • /
    • 제11권6호
    • /
    • pp.1793-1801
    • /
    • 2016
  • Speech enhancement is a challenging problem due to the diversity of noise sources and their effects in different applications. The goal of speech enhancement is to improve the quality and intelligibility of speech by reducing noise. Many research works in speech enhancement have been accomplished in English and other European Languages. There has been limited or no such works or efforts in the past in the context of Tamil speech enhancement in the literature. The aim of the proposed method is to reduce the background noise present in the Tamil speech signal by using wavelets. New modified thresholding function is introduced. The proposed method is evaluated on several speakers and under various noise conditions including White Gaussian noise, Babble noise and Car noise. The Signal to Noise Ratio (SNR), Mean Square Error (MSE) and Mean Opinion Score (MOS) results show that the proposed thresholding function improves the speech enhancement compared to the conventional hard and soft thresholding methods.

Crossflow Fan 주변의 유동 (Flows around crossflow fan)

  • 김재원;정윤영
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2001년도 춘계학술대회논문집E
    • /
    • pp.678-683
    • /
    • 2001
  • The present work has carried out experimental study on a cross-flow fan system with a simplified vortex wall scroll casing. A cross-flow fan test rig was constructed to obtain pressure rise and volume flow rate for various fan operating conditions. The performance estimation is using a wind tunnel with a motor driven damper for flow rate control and flows are quantitatively visualized by light scattering system with a pulsed laser. Min focus on the visualization is finding a eccentric vortex inside a fan which is a major factor reducing fan efficiency. Comprehensive engineering data are prepared for industrial applications and show a good agreement with a prior work by experimental measurements.

  • PDF

유리질 결합 CBN공구 제조시 기공량 변화 (The Change of Porosity During the Fabrication of Vitreous Bonded CBN Tools)

  • 양진
    • 한국세라믹학회지
    • /
    • 제35권9호
    • /
    • pp.988-994
    • /
    • 1998
  • In the manufacturing of vitreous bonded CBN tool the porosity change associated with various processing conditions, I. e. the sintering temperature and the size and the amount of abrasive grits was observed. In the case of sintering of vitreous bond material only the specimen density reached the maximum at 950$^{\circ}C$ and then the total porosity was increased slightly with the temperature above 950$^{\circ}C$. In the sintering of a-brasive grits and the vitreous bond material together a marked increase in the total porosity was found with the temperature above 950$^{\circ}C$ Reducing the grit size at the constant volume fraction of abrasive grits showed an increase in the total porosity at whole sintering temperature. On the contrary. it was observed that increasing the volume fraction of abrasive grits with a same size showed the increased open porosity simultaneously with decreased closed porosity at whole sintering temperature.

  • PDF

마하라노비스 다구찌(Mahalanobis Taguchi) 시스템을 이용한 박판 성형 공정의 최적화 (Optimization of Sheet Metal Forming Process Using Mahalanobis Taguchi System)

  • 김경모
    • 한국기계가공학회지
    • /
    • 제15권1호
    • /
    • pp.95-102
    • /
    • 2016
  • Wrinkle, spring-back, and fracture are major defects frequently found in the sheet metal forming process, and the reduction of such defects is difficult as they are affected by uncontrollable factors, such as variations in properties of the incoming material and process parameters. Without any countermeasures against these issues, attempts to reduce defects through optimal design methods often lead to failure. In this research, a new multi-attribute robust design methodology, based on the Mahalanobis Taguchi System (MTS), is presented for reducing the possibilities of wrinkle, spring-back, and fracture. MTS performs experimentation, based on the orthogonal array under various noise conditions, uses the SN ratio of the Mahalanobis distance as a performance metric. The proposed method is illustrated through a robust design of the sheet metal forming process of a cross member of automotive body.

Vat dyeing of Wool and Cotton fabrics with Sepia Melanin

  • Kim, Su-Jin;Jang, Jin-Ho
    • 한국염색가공학회지
    • /
    • 제22권2호
    • /
    • pp.88-93
    • /
    • 2010
  • Using extracted sepia melanin powder by repeated treatments with aqueous sodium hydroxide and acetic acid solutions, vat dyeing of wool and cotton fabrics was carried out under various dyeing conditions including concentration of melanin, alkali, reducing agent and salt, as well as dyeing time and temperature. A K/S of 25.3 for wool fabrics was obtained at the optimal dyeing condition with 9% owf melanin, 0.5g/L NaOH and 56g/L $Na_2S_2O_4$ without salt at $80^{\circ}C$ for 90minutes. The vat dyeing of sepia melanin was applicable to both cotton and wool fabrics but the wool showed higher dyeability. The color fastness properties of the dyed wool and cotton fabrics were excellent to washing, rubbing and light irradiation.