• Title/Summary/Keyword: Mass Efficiency

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Determination of Optimum Conditions for Mass Rearing of Cadra cautella(Walker)(Lepidoptera: Phycitidae) and Orius laevigatus(Fieber)(Hemiptera: Anthocoridae) (줄알락명나방(Cadra cautella)과 미끌애꽃노린재(Tyrophagus putrescentiae)의 증식 최적화 조건 탐색)

  • Ham, Eun Hye;Choi, Yong Seok;Lee, Jun Seok;Park, Jong Kyun
    • Journal of Sericultural and Entomological Science
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    • v.50 no.2
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    • pp.112-115
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    • 2012
  • To develop an efficient mass rearing system for Cadra cautella(Walker) and Orius laevigatus(Fieber) were investigated under the conditions of photoperiod 16L : 8D, $70{\pm}5%$ RH and $23{\pm}2^{\circ}C$. The highest efficiency rate(multiply 28.6) of C. cautella was achieved when using the rearing cage of $20{\ell}$ than $3{\ell}$. The highest efficiency rate(multiply 16.3) of O. laevigatus was achieved when using the rearing cage of $5{\ell}$ (adult 1,500, 10 pcs(10 cm) of plant of egg taking). The moth could be successfully reared with all food substrates tested, of which rice bran(43%) + chick feed(43%) + yeast(14%) assumed to be proper for mass-rearing in view of cost.

The damping efficiency of vortex-induced vibration by tuned-mass damper of a tower-supported steel stack

  • Homma, Shin;Maeda, Junji;Hanada, Naoya
    • Wind and Structures
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    • v.12 no.4
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    • pp.333-347
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    • 2009
  • Many tower-supported steel stacks have been constructed in Japan, primarily for economic reasons. However the dynamic behavior of these stacks under a strong wind is not well known and the wind load design standard for this type of a stack has not yet been formulated. In light of this situation, we carried out wind response observation of an operating tower-supported steel stack with and without a tuned-mass damper. The observation revealed the performance of the tuned-mass damper installed on the stack in order to control the wind-induced vibration. Based on the observed data, we performed a wind tunnel test of a specimen of the stack. In this paper we report the results of the wind tunnel test and some comparisons with the results of observation. Our findings are as follows: 1) the tuned-mass damper installed on the specimen in the wind tunnel test worked as well as the one on the observed stack, 2) the amplitude of the vortex-induced vibration of the specimen corresponded approximately to that of the observed stack, and 3) correlation between Scruton number and reduced amplitude, y/d, (y is amplitude, d is diameter) was confirmed by both the wind tunnel test and the observed results.

A Study on the Effects of Ignition Systems on the Heat Release Rate and Mass Fraction Burnt at a Constant Volume Combustion Chamber (정적연소기에서 점화장치가 열발생률과 잘량연소율에 미치는 영향에 관한 연구)

  • Song, Jeong-Hun;Lee, Gi-Hyeong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.24 no.11
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    • pp.1486-1496
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    • 2000
  • The initial flame kernel development and flame propagation in a constant volume combustion chamber is analyzed by the heat release rate and the mass fraction burnt. The combustion pressure is measured with a piezoelectric type pressure sensor. In order to evaluate the effects of ignition system and ignition energy on the flame propagation, four different ignition systems are designed and tested, and the ignition energy is varied by the dwell time. Several different spark plugs are also tested and examined to analysis the effects of electrodes on flame kernel development. The results show that the when the dwell time is increased, and when the spark plug gap is extended, heat release rate and the mass burnt fraction are increased. The materials and shapes of electrodes affect the flame development, because they change the energy transfer efficiency from electrical energy to chemical energy. The diameter of electrodes influences not only the heat release rate but also the mass burnt fraction as well.

Identification of Nandrolone and its Metabolite 5α-Estran-3β, 17α-Diol in Horse Urine after Chemical Derivatization by Liquid Chromatography Tandem Mass Spectrometry

  • Dubey, Saurabh;Beotra, Alka
    • Mass Spectrometry Letters
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    • v.8 no.4
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    • pp.90-97
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    • 2017
  • Androgenic anabolic steroids (AASs) are synthetic derivatives of testosterone with a common structure containing cyclopentanoperhydrophenanthrene nucleus. Their use enhances the muscle building capacity and is beneficial during performance. The AASs are one of the most abused group of substances in horse doping. Liquid chromatography tandem mass spectrometry ($LC/MS^n$) has been successfully applied to the detection of anabolic steroids in biological samples. However, the saturated hydroxysteroids viz: nandrolone, $5{\alpha}-estrane-3{\beta}$, $17{\alpha}-diol$ exhibit lower detection responses in electrospray ionisation (ESI) because of their poor ionisation efficiency. To overcome this limitation pre-column chemical derivatization has been introduced to enhance their detection responses in $LC-ESI-MS^n$ analysis. The aim of present study was to develop a sensitive method for identification and confirmation of nandrolone and its metabolite in horse urine incorporating pre-column derivatization using picolinic acid. The method consists of extraction of targeted steroid conjugates by solid phase extraction (SPE). The eluted steroid conjugates were hydrolysed by methanolysis and free steroids were recovered with liquid-liquid extraction. The resulting steroids were derivatized to form picolinoyl esters and identification was done using LC-ESI-MS/MS in positive ionization mode. The picolinated steroid adduct enhanced the detection levels in comparison to underivatized steroids.

Experimental Analysis of Mass Transfer Capability of Membrane Humidifier for PEMFC (이온 교환막 연료전지용 막 가습기의 물질전달 성능 실험)

  • Tak, Hyun-Woo;Kim, Kyung-Taek;Im, Seok-Yeon;Yu, Sang-Seok
    • Transactions of the Korean hydrogen and new energy society
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    • v.23 no.1
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    • pp.19-25
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    • 2012
  • The efficiency and life time of the Proton Exchange Membrane fuel cell (PEMFC) system is critically affected by incoming gas with humidity which should be maintained properly at normal operating conditions. Typically, incoming gas of automotive fuel cell is humidified by external humidifier but the characteristics of device is rarely reported. In this study, characteristics of water transfer in the membrane humidifiers have been experimentally investigated for flow rates of gas and for different flow arrangement under steady state condition. At first, capability of mass transfer through the membrane is examined at constant temperature. Then, the temperature distribution effect on the capability of mass transfer is tested over various inlet conditions. In summary, this research presents the mass transfer capability of hydrophilic membrane over various operating conditions.

Residence Time Distributions of Liquid pbase Flow and Mass Transfers in the Trickle Bed Reactor (점적상 반응기에서 액상흐름의 체류시간 분포 및 물질전달)

  • Kim, Ki-Chang
    • Journal of Industrial Technology
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    • v.6
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    • pp.19-31
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    • 1986
  • The residence time distribution of liquid flow in a 4.0cm diameter column packed with porous $Al_2O_3$ spheres of 0.37cm diameter were measured with pulse injections of a tracer under cocurrent trickling flow conditions. The mean residence time of liquid flow and liquid hold-up calculated by the transient curve of tracer were unaffected by gas flow rates under experimental ranges of liquid flow rates from 2.4 to $4.5(kg/m^2\;sec)$ and gas flow rates from 0 to $0.13(kg/m^2\;sec)$. The axial dispersion coefficient of liquid stream and apparent diffusivity of tracer in a micropore of solid particle were estimated from the response curve of tracer. The calculated Peclet No. were increased in ranges of 68-to 82 with a increasing of liquid mass velocity, and the external effective contacting efficiency between liquid and solid which can be expressed. by $(D_i)_{app}/D_i$ varied in ranges of 0.54 to 0.68 depending on the liquid flow rates. The gas to liquid(water) volumetric mass transfer coefficient were determined from desorption experiments with oxygen at $25^{\circ}C$ and 1 atm. The measured mass transfer coefficients were increased with liquid flow rates and the effect of gas flow rates on the mass transfer coefficient was insignificant.

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Comprehensive Analysis of Proteomic Differences between Escherichia coli K-12 and B Strains Using Multiplexed Isobaric Tandem Mass Tag (TMT) Labeling

  • Han, Mee-Jung
    • Journal of Microbiology and Biotechnology
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    • v.27 no.11
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    • pp.2028-2036
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    • 2017
  • The Escherichia coli K-12 and B strains are among the most frequently used bacterial hosts for scientific research and biotechnological applications. However, omics analyses have revealed that E. coli K-12 and B exhibit notably different genotypic and phenotypic attributes, even though they were derived from the same ancestor. In a previous study, we identified a limited number of proteins from the two strains using two-dimensional gel electrophoresis and tandem mass spectrometry (MS/MS). In this study, an in-depth analysis of the physiological behavior of the E. coli K-12 and B strains at the proteomic level was performed using six-plex isobaric tandem mass tag-based quantitative MS. Additionally, the best lysis buffer for increasing the efficiency of protein extraction was selected from three tested buffers prior to the quantitative proteomic analysis. This study identifies the largest number of proteins in the two E. coli strains reported to date and is the first to show the dynamics of these proteins. Notable differences in proteins associated with key cellular properties, including some metabolic pathways, the biosynthesis and degradation of amino acids, membrane integrity, cellular tolerance, and motility, were found between the two representative strains. Compared with previous studies, these proteomic results provide a more holistic view of the overall state of E. coli cells based on a single proteomic study and reveal significant insights into why the two strains show distinct phenotypes. Additionally, the resulting data provide in-depth information that will help fine-tune processes in the future.

A novel sensitivity method to structural damage estimation in bridges with moving mass

  • Mirzaee, Akbar;Shayanfar, Mohsenali;Abbasnia, Reza
    • Structural Engineering and Mechanics
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    • v.54 no.6
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    • pp.1217-1244
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    • 2015
  • In this research a theoretical and numerical study on a bridge damage detection procedure is presented based on vibration measurements collected from a set of accelerometers. This method, referred to as "Adjoint Variable Method", is a sensitivity-based finite element model updating method. The approach relies on minimizing a penalty function, which usually consists of the errors between the measured quantities and the corresponding predictions attained from the model. Moving mass is an interactive model and includes inertia effects between the model and mass. This interactive model is a time varying system and the proposed method is capable of detecting damage in this variable system. Robustness of the proposed method is illustrated by correct detection of the location and extension of predetermined single, multiple and random damages in all ranges of speed and mass ratio of moving vehicle. A comparative study on common sensitivity and the proposed method confirms its efficiency and performance improvement in sensitivity-based damage detection methods. In addition various possible sources of error, including the effects of measurement noise and initial assumption error in stability of method are also discussed.

A Study on the Burning Rate of Puzzle Mats (퍼즐매트의 연소속도에 관한 연구)

  • Park, Hyung-Ju
    • Journal of the Korean Society of Safety
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    • v.23 no.6
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    • pp.84-90
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    • 2008
  • The mass loss rate and heat release rate of puzzle mats were analysed using variable external irradiation level. Five samples of puzzle mat were tested in this study : Type A, B, C, D and E. Type A, B and C are all general grades whereas Type D and E are both Flame retardant grades. Incident heat fluxs of $25kW/m^2$, $35kW/m^2$, $50kW/m^2$ and $70kW/m^2$ were selected for these experiments. All samples were tested in the horizontal orientation and were wrapped in a single layer of aluminum foil. Each sample was nominally 20mm thick and 100mm square. The combustion heat and mass loss rate were carried out from Oxygen bomb calorimeter and mass loss calorimeter according to ISO 5660-1 respectively. Heat release rates were calculated using the equation ${\dot{Q}}=A_f{\dot{m}}"_X{\Delta}H_c=0.75A_f{\dot{m}}"{\Delta}H_c$. where $A_f$ is the horizontal burning area of the sample, $\dot{m}"$ is mass loss rate per unit area, ${\Delta}H_c$ is complete heat of combustion and 0.75 is combustion efficiency.

Braking Efficiency Calculation of Antiskid Brake System of a Fixed-Wing Aircraft (Dynamometer 시험을 통한 ABS 효율 계산)

  • Lee, Ki-Chang;Jeon, Jeong-Woo;Hwang, Don-Ha;Kom, Yong-Joo;Gu, Dae-Hyun
    • Proceedings of the KIEE Conference
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    • 2005.10b
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    • pp.222-224
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    • 2005
  • In the development of Antiskid Brake System(ABS) for a fixed-wing aircraft, the braking efficiency is the most essential parameters to evaluate the ABS, especially in slippery road conditions. The braking distance and landing distance of the aircraft depends on it. Since the ABS has been designed and implemented as a subsystem of the aircrafts, the braking performance was evaluated under dynamometer test, where the dynamometer emulates the aircraft mass. Under simulated wet road conditions, the dynamometer starts to be braked. This paper suggests practical braking efficiency calculation methods and the results and finally compares each method.

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