• 제목/요약/키워드: initial MC

검색결과 132건 처리시간 0.023초

Sensitivities of Salmonella typhimurium and Staphylococcus aureus to Ozonation in the Presence of Soluble Starch and Metal Ion Complex

  • Kim, Kee-Il;Kang, Suk-Nam;Lee, Ok-Hwan;Park, Jeong-Hyun
    • Food Science and Biotechnology
    • /
    • 제17권4호
    • /
    • pp.842-845
    • /
    • 2008
  • This study was carried out to investigate the bactericidal efficacy of concentration (0.1, 0.2, and 0.4 ppm) and exposure time (10 and 30 min) of ozone on bacterial reduction rate of Salmonella typhimurium KCTC 2541 and Staphylococcus aureus ATCC 13515 in the distilled water (DW), and DW supplemented with 0.2% soluble starch (SS), and metal ion (MC) using argentums (Ag) and copper (Cu). The significant bactericidal differences of S. aureus were showed in the treatments of DW and SS, respectively, at the concentration of ozone above 0.1 ppm for 10 min, comparing the respective initial bacterial counts. The bacterial reduction of S. aureus was more sensitive than that of S. typhimurum at the same concentration of ozone. The bacterial reduction rate of SS treatment was slightly lower than that of DW treatment at the same concentration of ozone (p<0.05), however, the bacterial reduction rate of strains improved in the MC treatment compared to the DW treatment at the same concentration of ozone.

Impact of a "TED-Style" presentation on potential patients' willingness to accept dental implant therapy: a one-group, pre-test post-test study

  • Ghanem, Henry;Afrashtehfar, Kelvin Ian;Abi-Nader, Samer;Tamimi, Faleh
    • The Journal of Advanced Prosthodontics
    • /
    • 제7권6호
    • /
    • pp.437-445
    • /
    • 2015
  • PURPOSE. A survey was conducted to assess the impact of a TED-like educational session on participants' willingness to accept dental implant therapy. MATERIALS AND METHODS. Volunteers interested in having information about dental implant therapies were recruited and asked to complete a two-part survey before and after an educational session. The initial survey elicited demographic information, self-perceived knowledge on dental implants and willingness to this kind of treatment. A "TED-style" presentation that provided information about dental implant treatments was conducted before asking the participants to complete a second set of questions assessing the impact of the session. RESULTS. The survey was completed by 104 individuals, 78.8% were women and the mean age was $66.5{\pm}10.8$. Before the educational session, 76.0% of the participants refused dental implants mainly due to lack of knowledge. After the educational session, the rejection of dental implants decreased by almost four folds to 20.2%. CONCLUSION. This study proved that an educational intervention can significantly increase willingness to accept treatment with dental implants in a segment of the population who is interested in having information about dental implant therapy. Furthermore, educational interventions, such as TED-like talks, might be useful to increase popular awareness on dental implant therapy.

미끄럼형 기계적 모델에 의한 디딤동작의 시뮬레이션 (Foot Strike Simulation by a Slider Type Mechanical Model)

  • 박해수;손웅희;윤용산
    • 대한의용생체공학회:의공학회지
    • /
    • 제10권3호
    • /
    • pp.269-278
    • /
    • 1989
  • The initial impact at foot strike is produced by a slider type mechanical model, which can be measured using a force platform to evaluate various shoes. The lower extremity and foot motion was filmed by a 16mm high speed movie camera and several points on the rear half of the shoe and those near the trochanter and the lateral epicondyle were digitized to provide the linear and angular positions and velocities during impact. With these observed kinematics, a slider type foot strike simulator composed of guide rail and sliding dummy is designed. The simulator system makes the artificial foot of the dummy with running shoe on it to follow the foot strike motion. The dummy has the relevant mass-spring-damper system modeled after McMahon's. The motion of the model is drived by the gravity force and the generated motion alone with the ground reaction forces are monitored by the same procedures afore mentioned producing the initial foot strike impact similar to the onto observed in human gait.

  • PDF

Flexural behavior of steel storage rack base-plate upright connections with concentric anchor bolts

  • Zhao, Xianzhong;Huang, Zhaoqi;Wang, Yue;Sivakumaran, Ken S.
    • Steel and Composite Structures
    • /
    • 제33권3호
    • /
    • pp.357-373
    • /
    • 2019
  • Steel storage racks are slender structures whose overall behavior and the capacity depend largely on the flexural behavior of the base-plate to upright connections and on the behavior of beam-to-column connections. The base-plate upright connection assembly details, anchor bolt position in particular, associated with the high-rise steel storage racks differ from those of normal height steel storage racks. Since flexural behavior of high-rise rack base connection is hitherto unavailable, this investigation experimentally establishes the flexural behavior of base-plate upright connections of high-rise steel storage racks. This investigation used an enhanced test setup and considered nine groups of three identical tests to investigate the influence of factors such as axial load, base plate thickness, anchor bolt size, bracket length, and upright thickness. The test observations show that the base-plate assembly may significantly influence the overall behavior of such connections. A rigid plate analytical model and an elastic plate analytical model for the overall rotations stiffness of base-plate upright connections with concentric anchor bolts were constructed, and were found to give better predictions of the initial stiffness of such connections. Analytical model based parametric studies highlight and quantify the interplay of components and provide a means for efficient maximization of overall rotational stiffness of concentrically anchor bolted high-rise rack base-plate upright connections.

벤토나이트가 포함된 자동산화 건조형 수성코팅제의 제조 및 특성 (Preparation and Properties of Autoxidation Drying Type Waterborne Coatings Containing Bentonite)

  • 이석기;구광모;이병교
    • 한국세라믹학회지
    • /
    • 제38권11호
    • /
    • pp.1067-1074
    • /
    • 2001
  • 수팽윤성 점토로서 벤토나이트(BEN), 유기금속 비누계 건조제, 아크릴계 바인더 및 코팅첨가제들을 배합하여 서로 성분이 다른 자동산화 건조형 수성코팅제(WBC-1, WBC-2, WBC-3, WBC-4) 4종류를 제조하였다. 제조한 수성코팅제(WBC)의 용액점도, 고형분, 유동학적인 성질 및 자동산화 건조성을 조사하였다. 또한 주조된 WBC 필름의 열안정성, 투명성 및 내수성을 측정하였고, WBC 필름의 표면형상을 주사탐침현미경으로 조사하였다. BEN이 포함된 WBC-2, WBC-3 및 WBC-4는 전단력에 따라 요변성이 나타남으로서 WBC의 저장안정성이 우수하였다. 자동산화형 WBC의 건조성은 건조제가 Mn/Zn/Ba=1/2/3의 비로 혼합되었을 때, 6$0^{\circ}C$에서 5초로서 최대치를 나타내었다. 또한 BEN이 포함된 WBC 필름의 초기분해온도와 투명성은 시판 WBC(MC-21W)의 필름보다 32.2~54.7$^{\circ}C$와 5.1~8.6%의 범위로 증가하였고, WBC 필름의 내수성은 MC-21W

  • PDF

IGRINS : 1st Year Operation & Future Plan

  • 이재준;김휘현;황나래;박찬;박병곤
    • 천문학회보
    • /
    • 제40권2호
    • /
    • pp.43.1-43.1
    • /
    • 2015
  • After successful commissioning observations in 2014, Immersion Grating Infrared Spectrograph (IGRINS) has been conducting its normal scientific operations on the 2.7m Harlan J. Smith telescope at the McDonald Observatory and has been producing high spectral resolution near-infrared spectroscopic data in excellent quality. We will present the current status of the instrument and its software packages, and highlight initial scientific results. In particular, we will discuss possibilities of having IGRINS on larger telescopes.

  • PDF

Laccase를 이용한 Triclosan의 처리 (Oxidative Transformation of Triclosan by Laccase)

  • 김영진
    • 한국환경보건학회지
    • /
    • 제31권1호
    • /
    • pp.61-65
    • /
    • 2005
  • The oxidative transformation of triclosan with laccase from Trametes versicolor was conducted in a closed, temperature controlled system containing phosphate buffer for pH control. The optimum pH for triclosan transformation showed about 5. Despite the observation that elevated temperatures tended to inactivate the enzyme, increased transformation of triclosan was observed up to $50^{\circ}C$. Of the mediators studied, ABTS was most successful at enhancing triclosan transformation. About 80% of the toxicity of the initial mixture was reduced after the enzymatic treatment. In the presence of 1.0 mM of anions such as sulfite, sulfide, and cyanide, triclosan transformation was greatly inhibited. Chloride and fluoride ions exhibited inhibition of triclosan transformation at 25 mM. Ferric ion substantially inhibited triclosan transformation at 1.0 mM.

GENERALISED PARAMETERS TECHNIQUE FOR IDENTIFICATION OF SEASONAL ARMA (SARMA) AND NON SEASONAL ARMA (NSARMA) MODELS

  • M. Sreenivasan;K. Sumathi
    • Journal of applied mathematics & informatics
    • /
    • 제4권1호
    • /
    • pp.135-135
    • /
    • 1997
  • Times series modeling plays an important role in the field of engineering, Statistics, Biomedicine etc. Model identification is one of crucial steps in the modeling of an AutoRegreesive Moving Average(ARMA(p, q)) process for real world problems. Many techniques have been developed in the literature (Salas et al., McLeod et al. etc.) for the identification of an ARMA(p, q) Model. In this paper, a new technique called The Generalised Parameters Technique is formulated for seasonal and non-seasonal ARMA model identification. This technique is very simple and can e applied to any given time series. Initial estimates of the AR parameters of the ARMA model are also obtained by this method. This model identification technique is validated through many theoretical and simulated examples.

결함발생 시점을 고려한 CANDU 압력관 결함의 확률론적 건전성평가 (Probabilistic Integrity Assessment of CANDU Pressure Tube for the Consideration of Flaw Generation Time)

  • 곽상록;이준성;김영진;박윤원
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2001년도 추계학술대회논문집A
    • /
    • pp.155-160
    • /
    • 2001
  • This paper describes a probabilistic fracture mechanics (PFM) analysis based on Monte Carlo (MC) simulation. In the analysis of CANDU pressure tube, it is necessary to perform the PFM analyses based on statistical consideration of flaw generation time. A depth and an aspect ratio of initial semi-elliptical surface crack, a fracture toughness value, delayed hydride cracking (DHC) velocity, and flaw generation time are assumed to be probabilistic variables. In all the analyses, degradation of fracture toughness due to neutron irradiation is considered. Also, the failure criteria considered are plastic collapse, unstable fracture and crack penetration. For the crack growth by DHC, the failure probability was evaluated in due consideration of flaw generation time.

  • PDF

염화에텐의 환원성 탈염소화 모텔을 이용한 수소 경쟁에 대한 평가

  • 이일수;배재호
    • 한국지하수토양환경학회:학술대회논문집
    • /
    • 한국지하수토양환경학회 2002년도 추계학술발표회
    • /
    • pp.117-121
    • /
    • 2002
  • A numerical model that describes the reductive dechlorination of tetrachloroethene(PCE) to ethene via cis-dichloroethene(CDCE) was developed. The model included two separated dehalogenator groups : one for PCE transformation to cDCE via TCE and the other for cDCE dehalogenation to ethene via VC, competitive inhibition between different chloroethene electron accepters, and competition for H$_2$ between dechlorination and methanogens. Model simulations suggest first, that PCE dechlorinators are better competitive with methanogens than cDCE dechlorinators. Second, not only the initial relative population size of dehalogenators and H$_2$-utilizing methanogens but also electron donor delivery strategies used greatly affects the degree of dehalogenation. As a result, all of factors in the above must be considered in order to achieve economical and successful bioremediation of contaminated soil and groundwater with chlorinated solvents.

  • PDF