• Defense and Technology
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• no.2 s.228
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• pp.16-19
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• 1998

• Defense and Technology
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• no.3 s.229
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• pp.18-21
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• 1998

• Journal of Microbiology and Biotechnology
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• v.19 no.5
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• pp.439-446
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• 2009

The biosynthesis study of antibiotics saframycin (SFM) in Streptomyces lavendulae and safracin (SAC) in Pseudomonas fluorescens demonstrated that 3-hydroxy-S-methyl-O-methyltyrosine (3hSmOmTyr), a nonproteinogenic amino acid, is the precursor of the tetrahydroisoquinoline molecular core. In the biosynthetic gene cluster of SAC/SFM, sacD/sfmD encodes a protein with high homology to each other but no sequence similarity to other known enzymes; sacF/sfmM2 and sacG/sfmM3 encode methyltransferases for C-methylation and O-methylation; and sacE/sfinF encodes a small protein with significant sequence similarity to the MbtH-like proteins, which are frequently found in the biosynthetic pathways of non ribosomal peptide antibiotics and siderophores. To address their function, the biosynthetic cassette of 3h5mOmTyr was heterologously expressed in S. coelicolor and P. putida, and an in-frame deletion and complementation in trans were carried out. The results revealed that (i) SfmD catalyzes the hydroxylation of aromatic rings; (ii) sacD/sacF/sacG in the SAC gene cluster and sfmD/sfmM2/sfmM3 in the SFM cluster are sufficient for the biosynthesis of 3h5mOmTyr; and (iii) the mbtH-like gene is not required for the biosynthesis of the 3h5mOmTyr precursor.

• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.1
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• pp.62-69
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• 2008

There has been a recent trend in Korea that treatments for combustible wastes among municipal solid waste (MSW) by those methods, such as incineration and landfill are restricted as much as possible and Mechanical Biological Treatment (MBT) are encouraged actively in order to promote resource recovery. To build and operate properly these facilities, the physicochemical characteristics of MSW should be analyzed precisely beforehand. In particular, designing a crusher or separator properly which is the main process in MBT facilities of MSW. require the information on the size distribution characteristics of MSW, but they are nor sufficient in the qualities and quantities yet as of now. Accordingly, this study aims to evaluate size distribution characteristics of MSW and its physicochemical characteristics by size. The samples of MSW were collected from detached dwelling area, apartment area, business area, and commercial area of A city in Korea. According to the result of analysis, paper records 29.78~60.02% by wet weight basis, so it was the most regardless of the regions where the wastes were generated. And in terms of element analysis, Carbon(C) was 34.77~44.39%, the largest friction, and Oxygen(O) was the next occupying 19.46~33.71%. As indices of RDFs, Chlorine(Cl) was 0.39~0.83%, so it was less than the standard, 2.0%(by dry weight basis); moreover, Sulfur(S) did not exceed the standard, 0.6%, either. In the size distribution of MSW, waste fraction ranging 50~80mm in diameter was the most in combustible waste while 30~50mm was in incombustible waste.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.3
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• pp.350-357
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• 2014

MRDS is a short range missile/rocket defense system which protects a main battle tank(MBT) from threats at a short range. It is composed of 2 radars, 2 infrared trackers(IRT)s, 1 fire control computer(FCC), 2 launchers and countermeasures. In this paper, the radar and the IRT models based on sensing errors, the FCC model based on filtering errors, the launcher model based on driving errors and the countermeasure model based on flying errors are proposed to analyze the defense performance with the approaching RPG-7 and the moving MBT. The simulation results are presented to evaluate and verify the effectiveness of the proposed method.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.3
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• pp.342-349
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• 2014

MRDS is a short range missile/rocket defense system which protects a main battle tank(MBT) from threats in a short range. It is composed of 2 radars, 2 infrared trackers(IRTs), 1 fire control computer(FCC), 2 launchers and countermeasures. To guarantee the performance of the MRDS, these components have to be mounted on the vehicle with the known positions and directions and it is required to compensate the alignment errors. In this paper, a system alignment method using angular error compensation is proposed to install its components within a tolerance on the MBT. The test results are presented to evaluate and verify the effectiveness of the proposed method.

• Polymer(Korea)
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• v.37 no.3
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• pp.269-275
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• 2013

Thiuram (DPTT, TMTD), thiazole (MBT, MBTS), sulfenamide (CBS, NOBS), and zinc containing thiuram (dithiocarbamate) (ZDBC) type accelerators were added into silica and carbon black filled natural rubber (NR) compounds. Their effects on vulcanization time and rate were compared. The vulcanization rate of thiuram type accelerator added compounds showed the fastest rate, followed by thiazole and sulfenamide types. Silica filled natural rubber (NR) compounds showed a slower vulcanization time ($t_{s2}$, $t_{10}$, $t_{90}$) and lower cure rate index (CRI) than carbon black filled ones upon each accelerator.

• Korean Journal of Human Ecology
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• v.14 no.1
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• pp.209-216
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• 2005

The concentrations of organotin compounds in fish and shellfish from Guryongpo harbor were analyzed. The concentrations of TBT, DBT and MBT in fish were in the range of $15.68{\sim}52.93\;ng/g$(average 28.65 ng/g), $13.95{\sim}72.16\;ng/g$(average 26.99 ng/g) and $37.73{\sim}133.59\;ng/g$(average 85.18 ng/g), respectively. The BT compound concentrations in intestine of fish were higher than those in muscle. Overall ranges of TBT, DBT and MBT concentrations in shellfish were $42.15{\sim}56.13\;ng/g$(average 50.94 ng/g), $34.16{\sim}52.82\;ng/g$(average 42.79 ng/g) and $41.25-72.60\;ng/g$(average 53.71 ng/g), respectively. The BT compound concentrations of shellfish were higher than those of fish. The concentrations of TPT and DPT in fish were $0.47{\sim}3.90\;ng/g$(average 2.33 ng/g) and $ND{\sim}0.56\;ng/g$(average 0.15 ng/g), but MPT was not detected. The concentrations of TPT, DPT and MPT in shellfish were in the range of $10.24{\sim}21.67\;ng/g$(average 17.45 ng/g), $3.32{\sim}4.78\;ng/g$(average 3.91 ng/g) and $0.11{\sim}0.36\;ng/g$(average 0.25 ng/g), respectively. In addition, the MBT ratio was highest among BT compounds, but the TPT ratio was the highest among PT compounds. Taken together, the concentrations of organotin compounds in fish and shellfish from Guryongpo harbor was not higher than those from other harbors in Korea.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.2
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• pp.44-51
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• 2005

According to the increasing concern on the global environment, the $CO_2$ regulation has been discussed including automobile emission regulation. In order to cope with this rapid changing circumstances, the development of an ultra low emission and super fuel economy automobile is essential. Direct injection LPG engine is the one of the possible future engine to maximize the engine efficiency. This experimental study for the development of direct injection LPG engine technology is promoted with two parts; spray characteristics of high pressure swirl injector, and performance characteristics of direct injection LPG engine. Engine characteristics according to the fuel was analyzed in order to establish stratified combustion technology for LPG engine by using the DISI engine. In the engine experiment, control system was manufactured for gasoline and LPG fuel. The engine was modified 2,000 cc GDI engine (fuel supply device, fuel injection device). Through this experiment, engine operating condition, engine speed and spark timing (MBT), fuel injection position, and fuel rate were investigated.

• Elastomers and Composites
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• v.13 no.4
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• pp.277-281
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• 1978

1. A good retarder reacts fast with MBT and. forms a non-scorchy accelerator. 2. The decrease in cure rate$(k_1)$ is attributable to the slow cure rate of 2-cyclohexyldithiobenzothiazole(CDB). 3. Cyclohexyl polysulfides(CPS) and cyclohexylthioamine are believed to be also involved in the cure retardation. 4. The new retarder can stop crosslinking by intercepting the crosslink precursors. 5. Formation of cyclohexyl polysulfides and their lack of curing property may be responsible for the low state of cure when the new retarde is used. These results are schematically summarized in Figure 7.