• Journal of Microbiology and Biotechnology
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• 제9권5호
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• pp.637-645
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• 1999

Two putative regulator genes, mocR and mocS, of the moc (mannityl opine catabolism) operons in pTi15955 of the octopine-/mannityl opine-type Agrobacterium tumefaciens strain 15955, were tested for their possible roles as repressors in the moc operons. The regions upstream of macC and mocD, the first structural genes in the two divergently oriented moc operons, were transcriptionally fused into the promoterless lacZ reporter gene. Each of the lacZ-fusions was introduced into Agrobacterium strain UIA5, a Ti plasmid-cured derivative, harboring either a mocR or a mocS clone. The resulting strains were grown in media containing various sugar sources, and the $\beta$-galactosidase activities were quantitatively measured. The results suggested that MocR repressed the expression of macC and macD. The expression of the fused $\beta$-galactosidase was not induced by mannopine (MOP) or possible catabolic intermediates of the opine, e.g. santhopine (SOP), glucose, mannose, or glutamine. However, the repression was significantly relieved by the supplementation of MOP and the concomitant introduction of the agcA gene encoding MOP cyclase that catalyzes the lactonization of MOP to agropine (AGR). These results suggested that AGR, rather than MOP or the other catabolic intermediates, is the inducer for the expression of the operon. On the contrary to previous report showing that the induction levels of macC and macD were lowered by the supplementation of inorganic nitrogen in media, the expression of these genes was not affected by the level of nitrogen in our reporter system. MocS did not strongly repress the expressions of macC and mocD. It is possible that MocS may be involved in the regulation of the operons present downstream of the moc operon, which are responsible for the utilization of mannopinic acid and agropinic acid.

• Environmental Engineering Research
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• 제22권1호
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• pp.95-107
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• 2017

Adsorption equilibrium and kinetic behavior of two toxic heavy metals hexavalent chromium [Cr(VI)] and mercury [Hg(II)] on mustard oil cake (MOC) was studied. Isotherm of total chromium was of concave type (S1 type) suggesting cooperative adsorption. Total chromium adsorption followed BET isotherm model. Isotherm of Hg(II) was of L3 type with monolayer followed by multilayer formation due to blockage of pores of MOC at lower concentration of Hg(II). Combined BET-Langmuir and BET-Freundlich models were appropriate to predict Hg(II) adsorption data on MOC. Boyd's model confirmed that external mass transfer was rate limiting step for both total chromium and Hg(II) adsorptions with average diffusivity of $1.09{\times}10^{-16}$ and $0.97m^2/sec$, respectively. Desorption was more than 60% with Hg(II), but poor with chromium. The optimum pH for adsorptions of total chromium and Hg(II) were 2-3 and 5, respectively. At strong acidic pH, Cr(VI) was adsorbed by ion exchange mechanism and after adsorption reduced to Cr(III) and remained on MOC surface. Hg(II) removal was achieved by complexation of $HgCl_2$ with deprotonated amine ($-NH_2$) and carboxyl (COO-) groups of MOC.

• Asian-Australasian Journal of Animal Sciences
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• 제12권5호
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• pp.715-722
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• 1999

On a urea-molasses-straw (3:15:82, UMS) based diet, effect of graded levels of mustard oil cake (MOC) supplementation on the performances of native bulls has been studied. Four cannulated adult Bos indicus bulls of $415({\pm}44.6)kg$ live weight and 80 months old, were given daily either of 0, 200, 400 or 800 g of MOC in four periods in a $4{\times}4$ latin square design. Besides, each animal also received 200 g of each of molasses and wheat bran and a mineral mixture. For unit (1 g) increase in MOC intake, total DM intake increased by 0.8 g/d ($r^2=0.88$) but no change in the straw DM intake. With the increasing levels of MOC, crude protein (CP) digestibility increased exponentially with an asymptotic value of 72%. However, MOC level had no effect on the digestibilities of DM, OM and ADF. Similarly, rumen degradability of rice straw was also not affected by the level of dietary MOC, and mean straw DM degradabilities were 15, 21. 28, 37, 47 and 51% at 8, 16, 24, 48, 72 and 96 hours of incubation respectively. Microbial N yield per kg digestible organic matter apparently fermented in the rumen were 7.46, 8.77, 6.88 and 5.96 g respectively for 0, 200, 400 or 800 g of dietary MOC. For each gram increase in dietary MOC, N intake and N balance increased by 0.054 g/d ($r^2=0.998$) and $0.59mg\;N/kg\;W^{0.75}/d$ ($r^2=0.99$) respectively. Nitrogen balance was estimated to be attained at the N intakes of $246mg\;N/kg\;W^{0.75}/d$. Thus, on a UMS-based diet supplementation of MOC up to 800 g (10% of total intake) of the dietary intake had little or no effect on intake, digestibility, rumen parameters, and microbial N yield but slightly increased the N balance. However marginal response to MOC supplementation is probably due to the high degradability of MOC protein in the rumen. Thus, any substantial positive response of MOC supplementation on a UMS-based diet can probably be achieved by reducing its protein degradability in the rumen.

• Asian-Australasian Journal of Animal Sciences
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• 제18권1호
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• pp.42-47
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• 2005

The possibility of using Moringa oleifera as a ruminant protein supplement was investigated by comparison between nutritive and anti-nutritive value of its different morphological parts with that of conventionally used Leucaena leucocephala leaf meal (LL). Parameters determined were chemical composition, rumen degradable protein (RDP), acid detergent insoluble protein (ADIP), pepsin soluble protein (PESP), non-protein nitrogen (NPN) total soluble protein (TSP) and protein potentially digested in the intestine (PDI). Total phenols (TP) and total extractable tannins (TET) were also evaluated as anti-nutritive factors. In vitro gas production characteristics were measured and organic matter digestibility (OMD) was estimated basing on 24 h-gas production. Crude protein content ranged from 265-308 g/kg DM in M. oleifera leaves (MOL) and seed cake (MOC) respectively. Leucaena leucocephala and Moringa oleifera soft twigs and leaves (MOLSTL) had CP content of 236 and 195 g/kg DM while Moringa oleifera soft twigs alone (MOST) and Moringa oleifera bucks (MOB) had 160, 114 and 69.3 g/kg DM respectively. RDP was highest in (MOC) (181 g/kg DM) followed by (MOL) (177 g/kg DM) and was lowest in MOB (40 g/kg DM). The proportion of the protein that was not available to the animal (ADIP) was (p<0.05) higher in MOL and MOC (72 and 73 g/kg DM) respectively and lowest in LL (29 g/kg DM). The PDI was high in LL (74 g/kg DM) followed by MOC (55 g/kg DM) then MOL (16 g/kg DM). PESP was highest (p<0.05) in MOC followed by MOL then LL (273, 200 and 163 g/kg DM respectively). MOC exhibited highest NPN content (116 g/kg DM) and was lowest in MOB (18 g/kg DM) (p<0.05). Highly (p<0.05) TSP was observed in MOC and MOL (308 and 265 g/kg DM respectively) followed by LL (236 g/kg DM). MOL had negligible TET (20 g/kg DM) when compared with about 70 g/kg DM in LL. Highly (p<0.05) b and a+b values were observed for MOLSTL (602 and 691 g/kg DM respectively) followed by MOL (490 and 538 g/kg DM). Highest c value was observed in MOSTL followed by MOC and MOL (0.064, 0.056 and 0.053 rate/hour) respectively. OMD was highest (p<0.05) for MOSTL followed by MOC and then MOL (579, 579 and 562 g/kg DM respectively). LL exhibited lower (p<0.05) OMD (467 g/kg DM). It was concluded from this study that the high crude protein content in MOL and MOLST could be well utilized by ruminant animals and increase animal performance however, high proportion of unavailable protein to the lower gut of animals and high rumen degradable protein due to negligible tannin content render it a relatively poor protein supplement for ruminants. MOC can be a best alternative protein supplement to leaves and leaves and soft twigs for ruminants.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 Asia Navigation Conference
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• pp.213-219
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• 2006

Planning Environment Impact Assessment is regarded as one of the most important measures to achieve sustainable development in China. Conduct environment impact assessment for port planning was prescribed by Environment impact Assessment Law of the People's Republic of China. This Paper introduces the basic concept of Planning Environment Impact Assessment and Port Planning firstly, and then discusses the assessment indicators and assessment methods adopted in the Environment Impact Assessment for port planning. At last, the application of the indicators and methods are illustrated in case studies based on the practice on Port Planning's Environment Assessment in China.

• 한국정보통신학회논문지
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• 제18권10호
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• pp.2503-2508
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• 2014

본 연구는 진공차단기 기계식 보조접점(MOC)의 구조적인 취약성을 해결하기 위해 전자식 센서 기술을 이용한 전자식 보조접점(EOC) 개발에 선행되어야할 센서의 선정 및 노이즈 시험에 관한 것으로, 기존 기계적 보조접점(MOC)에서 발생하는 반복적인 떨림 및 반동 현상에 의한 접점 오동작을 최소화하는 제품을 개발하는 것을 최종 목표로 하였다. 실험 결과, 차단기 투입 및 개방시 개방시의 써지전압 상승속도가 투입시 보다 4.2배 빠른 것으로 측정되었고, 소음크기는 각각 120dB, 110dB로 측정되었다. 상용주파과전압 60kV를 인가하였을 때 진공차단기 투입 및 개방시 센서에서 출력되는 파형은 일그러짐이 없이 정상적으로 동작됨을 알 수 있었다. 그리고 150kV $1.2{\times}50{\mu}s$의 충격파를 인가하였을 때 센서의 투입 및 개방측 출력접점의 전압파형이 일그러짐이 없이 정상상태를 유지하였으며, 2500A의 전류를 인가하였을 때 자계 잡음을 측정한 결과, 전압파형이 일그러짐이 없이 정상적으로 동작하였다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 1989년도 수공학논총 제31권
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• pp.133-143
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• 1989

단면이 급축소 되는 관에서 액체의 급속한 채움에 의한 수격현상을 연속, 운동량, 그리고 에너지 방정식들을 이용하여 해석적으로 표시하였다. 이러한 관에 기존 수학모형인 "MOC"와 "RCT"를 적용한 결과에 의하면, 이러한 관단면의 급변화에 의하여 수격작용이 예상되는 경우의 부정류해석에는 Rigid Column Method의 사용은 제한 되어야 하며 Method of Characteristics를 사용하여야 한다.teristics를 사용하여야 한다.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2005년도 춘계 학술대회논문집
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• pp.173-181
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• 2005

A fluid transient analysis for the propellant flow in a monopropellant propulsion system is conducted using the method of characteristics (MOC). Algebraic simultaneous equations method and Clamor's rule method utilized to drive the compatible and characteristic equations are reviewed to understand MOC more extensively. The identification of fluid transient phenomena of propulsion system of Koreasat 1 is carried out through parametric studies. Also this work describes the reason that the propulsion system of Koreasat 1 has no orifice to control flow transients or to limit the initial hydrazine flow rate for the first-pulse firing.

• 한국전산유체공학회지
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• 제10권2호
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• pp.69-81
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• 2005

A fluid transient analysis for the propellant flow in a monopropellant propulsion system is conducted by using the method of characteristics(MOC). It reviews algebraic simultaneous equations method and Cramer's rule method utilized to drive the compatible and characteristic equations to understand MOC extensively. The identification of fluid transient phenomena of propulsion system of Koreasat 1 is carried out through parametric studies. The valve response time is one of the dominant parameters governing the fluid transient phenomena. The results show that the shorter closing time induces the greater pressure response amplitude. And it shows that the installation of in-line orifice is effectively to limit the fluid transients in rapid valve response time and at high pressure. But it seems that the effect of orifice weakens at slow valve response time and at low pressures.

• Journal of Advanced Marine Engineering and Technology
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• 제22권5호
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• pp.693-701
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• 1998

This study presents result of comparison between two other numerical method method of char-acteristics(MOC) and Lax-Wendroff method(LWM) applied at wave action analysis of intake and exhaust pipe in terms of calculated pressure velocity and emitted noise in the time and the fre-quency domain by means of fast Fourier transform analysis. Particularly FCT(Flux Corrected Transport)scheme is appended to LWM to protest unaceptable overshoots occurring near discon-tinuity. The final conclusion of this study is that MOC should be replaced by a second order finite difference approach because of larger contributions due to high frequency components than the results from the method of characteristics. Clear benefits we can get by change are faster calcula-tion higher accuracy conservation of mass and consistent calculation method.