• Title/Summary/Keyword: scale effect

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The Effect of Cultural Conditions on the Aflatoxin Production of Aspergillus Flavus ATCC 15517 (배양조건이 Aspergillus flavus ATCC 15517의 Aflatoxin 생성에 미치는 영향)

  • 정덕화;이용욱;김용호;김성영;김종규
    • Journal of Environmental Health Sciences
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    • v.16 no.1
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    • pp.45-53
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    • 1990
  • To investigate the effect of cultural condition on the aflatoxin production of Aspergillus flayus ATCC 15517, mixed culture with Aspergillus niger, better kind of media and size of Cultural vessels were examined. YES medium was better than SLS medium for this study. Small scale test tube culture was showed the possibility to simply examine the growth, total acidity, pH and aflatoxin production during cultivation, and also could reduce the second contamination of aflatoxin B1 from large scale broth cultured. Especially ELISA method is simple, sensitive and specific and therefore well suited to small scale of test tube culture. Mixed culture significantly reduced the aflatoxin production of Aspergillus fiavus ATCC 15517 and showed almost 95% inhibition of that level during the incubtation.

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A study on stream morphological characteristics according to effect of Map Scale (지도축척의 영향에 따른 하천형태학적 특성연구)

  • 안상진;조용진
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.23 no.1
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    • pp.64-74
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    • 1981
  • The stream morphological characteristics of watershed have important influence upon the analysis of runoff. In this study, the effect of the map scale on the stream morphological characteristics was used on the data taken from 15'(1:50, 000) and 7'30"(1 :25,000) topographic maps which could cover the whole Miho River basin This basin are the first tributary of the Geum. River. Otherwise, the longitudinal stream bed profile was calculated by Yang's theoretical stream bed profile, equilibrium profile and actual profile. In the result of this investigation the conclusion is that the resultant relationship obtained from different topographic maps in the scale on the same stream system has come upon the same result as the stream morphological characteristics. Therefore, the great amount of time and effort can be saved in studing the stream morphological charecteristics by using the 15' instead of the 7'30"map system excluding the first order streams.

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Study on the Ejected Plume from Opening Regarding Side-wall Effect in Fire (측벽효과를 고려한 개구부 분출화염 거동 연구)

  • Jeong, Jae-Gun;Shin, Yi-Chul
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2016.05a
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    • pp.219-220
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    • 2016
  • The behavior of fire plumes has not yet been clearly identified for cases where sidewalls are installed near an opening in an unconfined space. In this research, we aim to quantitatively identify the effects on fire spread when sidewalls are located on both sides of an opening. Specifically, we focus on the effects on the fire plume of the relation between the location of sidewalls and the opening, and carry out a scale-model experiment to devise a flame height model and to evaluate the temperature distribution along the central axis of the flame.

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Combustion Characteristics in Small Combustion Chamber Size about Quenching Distance (소염 거리에 근접하는 소형 연소실 환경에서의 연소특성)

  • Lee, Dae-Hoon;Choi, Kwon-Hyoung;Kwon, Se-Jin
    • Journal of the Korean Society of Combustion
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    • v.5 no.2
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    • pp.63-68
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    • 2000
  • Combustion phenomenon in scale-downed combustor is investigated. As the combustor scale decreases surface to volume ratio increases and chamber size approaches quenching distance. As the combustor scales down surface to volume ratio increases resulting increased heat loss. And this heat loss can affect quenching and instability of the flame. To investigate this effect plastic mini combustor is made. Stoichiometricaly premixed Hydrogen / air gas is used as fuel. Initial chamber pressure and chamber size are varied and the effects are evaluated. Peak pressure decreased with the decrease in chamber height. As initial chamber pressure decreases peak pressure decreases and this change is more important than scale down effect till the chamber height of 1mm. With this result and further information following the experiments design parameter for micro engine can be established.

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Free vibration investigation of FG nanoscale plate using nonlocal two variables integral refined plate theory

  • Balubaid, Mohammed;Tounsi, Abdelouahed;Dakhel, B.;Mahmoud, S.R.
    • Computers and Concrete
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    • v.24 no.6
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    • pp.579-586
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    • 2019
  • In this research paper, the free vibrational behavior of the simply supported FG nano-plate is studied using the nonlocal two variables integral refined plate theory. The present model takes into account the small scale effect. The effective's properties of the plate change according to the power law variation (P-FGM). The equations of motion of the system are determined and resolved via Hamilton's principle and Navier procedure, respectively. The validity and efficiency of the current model are confirmed by comparing the results with those given in the literature. At the last section, several numerical results are presented to show the various parameters influencing the vibrational behavior such as the small-scale effect, geometry ratio, material index and aspect ratio.

Four Case of HIVD-Lumbar Spine Patient Treated with Acupotomy (침도침 시술을 통한 요추추간판탈출증 환자 4명의 증례보고)

  • Kwak, Byung-Min;Hong, Kwon-Eui
    • Journal of Acupuncture Research
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    • v.25 no.4
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    • pp.149-156
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    • 2008
  • Objectives : The purpose of this study is to report the effect of acupotomy for patients with Lumbar intervertebral disc Herniation. Methods : We treated Four patients who have HIVD of L-spine with acupotomy. Visual analog scores(VAS) and Oswestry Low-back pain Disabiliby Index(ODI) were compared before-treatment with after-tretment. When the patients is discharged, the satisfaction of acupotomy were graded by Five-point Likert scale. Results : VAS and ODI were decreased at all case. Likert scale point were cheked as grade 4 at all case. Conclusions : This study shows acupotomy has useful effect on HIVD of L-spine.

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Effect of TiC Content on Oxidation Behavior of Sintered WC-TiC-TaC Alloys

  • Tanaka, Hiroki;Mouri, Shigeki;Nakahara, Kenji;Sano, Hideaki;Zheng, Guo Bin;Uchiyama, Yasuo
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09a
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    • pp.352-353
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    • 2006
  • The effect of TiC content on oxidation behavior of the sintered WC-TiC-TaC alloys with 2 mass% TaC and different TiC amounts of 3-45 mass% was investigated through oxidation tests in air at 973K. As a result of the tests, it was revealed that with increasing TiC content in the alloys, mass changes caused by oxidation and thickness of the scale decreased. Thus, it is considered that the main component of the scales changed gradually from $WO_3$ to $TiO_2$ with increasing TiC content in the alloys, and oxygen diffusion through the scale to the alloys was inhibited gradually.

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Effect of Fe on the High Temperature Oxidation of TiAl Alloys (TiAl 합금의 고온 산화에 미치는 Fe의 영향)

  • 김미현;이동복
    • Journal of the Korean institute of surface engineering
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    • v.33 no.4
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    • pp.281-288
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    • 2000
  • To understand the effect of Fe on the oxidation behavior of TiAl alloys, TiAl-(2, 4, 6at% )Fe were oxidized at 800 and 90$0^{\circ}C$ in air. The oxidation resistance of TiAl-Fe alloys increased with increasing an iron content. The scales formed consisted of an outer $TiO_2$ layer, an intermediate $A1_2$$O_3$ layer, and an inner mixed ($TiO_2$+$A1_2$$O_3$) layer, being similar to other common TiAl alloys. But, the scales formed on TiAl-Fe alloys were generally thin compared to those formed on pure TiAl, and contained dissolved iron. Below the oxide scale, an oxygen affected zone was formed. This beneficial effects of Fe on increasing the oxidation resistance and scale adherence of TiAl alloys were attributed to the refinement of oxide grains, increased scale adherence and the enhanced alumina-forming tendency.

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Scale effect of mechanical properties of jointed rock mass: A numerical study based on particle flow code

  • Wang, Xiao;Yuan, Wei;Yan, Yatao;Zhang, Xue
    • Geomechanics and Engineering
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    • v.21 no.3
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    • pp.259-268
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    • 2020
  • The synthetic rock mass (SRM) were used to investigate the influence of specimen size on the mechanical properties of jointed rock mass. The SRM were established based on parallel bond model (PBM) and smooth joint model (SJM) and the scaled rock specimens were sampled in two SRMs considering three sampling locations. The research results show that the smaller the initial fracture density is, the greater the uniaxial compressive strength (UCS), elastic modulus (E) is when compared with the same sampling location. The mechanical properties of rock specimens obtained by different sampling methods in different SRMs have different scale effects. The strength of rock specimens with more new cracks is not necessarily less than that of rock specimens with fewer new cracks and the failure of rock is caused by the formation of macro-fracture surface.

Effect of Modified Hyeongbangjiwhang-tang for essential tremor after total vaginal hysterectomy : Case report (전자궁적출술 후 발생한 본태성 떨림에 대한 형방지황탕 가감 투여: 증례보고)

  • Kim, Bomin;Jo, Hee-Geun
    • Journal of Sasang Constitutional Medicine
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    • v.30 no.4
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    • pp.59-66
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    • 2018
  • Objectives This case reports the effect of Modified Hyeongbangjiwhang-tang for essential tremor after total vaginal hysterectomy. Methods The patient was treated with Modified Hyeongbangjiwhang-tang three times a day. To differentiate other diseases, we took her medical history. And, we used the Verbal Numerical Rating Scale (VNRS) and Gastrointestinal Symptom Rating Scale (GSRS) to assess tremor and gastrointestinal symptoms. Results Treatment with modified Hyeongbangjiwhang-tang resulted in a decrease in the patient's complaints of symptoms. Also, VNRS and GSRS scale were improved. Adverse effects were not observed. Conclusions Modified Hyeongbangjiwhang-tang may be effective for essential tremor after total vaginal hysterectomy.