• Journal of Microbiology and Biotechnology
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• v.13 no.5
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• pp.819-822
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• 2003

Polyketides are an extensive class of secondary metabolites with diverse molecular structures and biological activities. A plasmid-based minimal polyketide synthase (PKS) expression cassette was constructed using a subset of actinorhodin (act) biosynthetic genes (actI-orfl, actI-orf2, actI-orf3, actIII, actⅦ, and actIV) from Streptomyces coelicolor, which specify the construction of an orange-fluorescent anthraquinone product aloesaponarin II, a type II polyketide compound derived from one acetyl coenzyme A and 7 malonyl coenzyme A extender units. This system was designed as an indicator pathway in S. parvulus to generate a hybrid type II polyketide compound via gene-specific replacement. The act ${\beta}-ketoacyl$ synthase unit (actI-orfl and actI-orf2) in the expression cassette was specifically replaced with oxytetracycline ${\beta}-ketoacyl$ synthase otcY-orfl and otcY-orf2). This plasmid-based hybrid PKS cassette generated a novel orange-fluorescent compound structurally different from aloesaponarin II in both S. lividans and S. parvulus. In addition, several additional distinctive blue-fluorescent compounds were detected, when this hybrid PKS cassette was expressed in S. coelicolor B78 (actI-orf2 mutant), implying that the expression of plasmid-based hybrid PKS cassette in Streptomyces species should be an efficient way of generating hybrid type II polyketide compounds.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.424-433
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• 2006

This paper studies the field applicability of the Special Chemical grouting Method(SCM) in reinforcing and reducing permeability of the back of an existing continuous wall. SCM uses double rod which imposes intermediate pressure$(981\sim9,810kPa)$ to disturb, cut, discharge, and mix the ground. It is observed that a bulb is formed by using cement paste and environmentally friendly injection materials with minimal alkali leaching. Uniaxial compression tests, test for chemical properties and fish poison test are performed. Test results indicate that the method results in higher durability, less leaching through use of the environmentally friendly injection material, and faster mobilization of the strength. In addition, field tests confirm the formation of the bulb and the seepage cutoff wall.

• Asia pacific journal of information systems
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• v.13 no.1
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• pp.103-118
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• 2003

Software project planning is usually represented by a project activity network that is composed of stages of tasks to be done and precedence restrictions among them. The project network is very complex and its construction requires a vast amount of field knowledge and experience. So this study proposes a case-based reasoning approach that can generate the project network automatically based on the past cases and modification knowledge. For the case indexing, we have adopted 17 factors, each with a few alternative values. A special structure of this problem is that the modification effort can be identified by each factor independently. Thus it is manageable to identify 85 primitive modification actions(add and delete activities) and estimate its modification efforts in advance. A specific case requires a combination of primitive modifications. Based on the modification effort knowledge, we have adopted the Least Modification approach as a metric of similarity between a new project and past cases. Using the Least Modification approach and modification knowledge base, we can automatically generate the project network. To validate the performance of Least Modification approach, we have compared its performance with an ordinary minimal distance approach for 21 test cases. The experiment showed that the Least Modification approach could reduce the modification effort significantly.

• Archives of Reconstructive Microsurgery
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• v.25 no.1
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• pp.19-24
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• 2016

Urethral reconstruction is a problematic issue, thus its management can be challenging. Different methods using various materials were introduced for urethral reconstruction. The authors have made some changes in the groin flap surgery, affording more successful urethral reconstruction for defects of long urethra and penile soft tissue. A 45-year-old male requested both functional and cosmetic reconstruction of his defected penis, caused by an iatrogenic urethral injury and chronic infection following removal of paraffin self-injected on the penile shaft. The defect affected the full length of the penile urethra, corpus spongiosum, and prepuce. A groin flap was designed, measuring $28{\times}10cm$. The most distal flap was utilized for the construction of the luminal surface of the neourethra; relaxed length measuring 8 cm, and the lumen wide enough. Competent external meatus and neourethra was confirmed by retrograde cystogram and the patient voided with sufficient urine caliber up to 2 years follow-up. This operative technique has advantages. Donor sites have non-hair bearing skin for the neourethra and minimal or almost notrecognizable donor site morbidity. After surgery, the patient was relieved from voiding difficulties combined with psychological stress. The author would like to introduce a unique approach for the urethral and ventral phalloplasty using the groin flap.

• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.4
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• pp.826-839
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• 2014

Fire is a continuous threat to FPSO topside modules as large amounts of oil and gas are passing through the modules. As a conventional measure to mitigate structural failure under fire, passive fire protection (PFP) coatings are widely used on main structural members. However, an excessive use of PFP coatings can cause considerable cost for material purchase, installation, inspection and maintenance. Long installation time can be a risk since the work should be done nearly at the last fabrication stage. Thus, the minimal use of PFP can be beneficial to the reduction of construction cost and the avoidance of schedule delay. This paper presents a few case studies on how different applications of PFP have influence on collapse time of a FPSO module structure. A series of heat analysis and thermal elasto-plastic FE analysis are performed for different PFP coatings and the resultant collapse time and the amount of PFP coatings are compared with each other.

• Microbiology and Biotechnology Letters
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• v.38 no.3
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• pp.235-243
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• 2010

For decades, traditional mutation breeding technologies using spontaneous mutation, chemicals, or conventional radiation sources have contributed greatly to the improvement of crops and microorganisms of agricultural and industrial importance. However, new mutagens that can generate more diverse mutation spectra with minimal damage to the original organism are always in need. In this regard, ion beam irradiation, including proton-, helium-, and heavier-charged particle irradiation, is considered to be superior to traditional radiation mutagenesis. In particular, it has been suggested that ion beams predominantly produce strand breaks that often lead to mutations, which is not a situation frequently observed in mutagenesis induced by gamma-ray exposure. In this review, we briefly describe the general principles and history of particle accelerators, and then introduce their successful application in ion beam technology for the improvement of crops and microbes. In particular, a 100-MeV proton beam accelerator currently under construction by the Proton Engineering Frontier Project (PEFP) is discussed. The PEFP accelerator will hopefully prompt the utilization of ion beam technology for strain improvement, as well as for use in nuclear physics, medical science, biology, space technology, radiation technology and basic sciences.

• Journal of the Korea Society of Computer and Information
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• v.16 no.5
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• pp.153-162
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• 2011

The minimum cut problem is to minimize c(S,T), that is, to determine source S and sink T such that the capacity of the S-T cut is minimal. The flow-based algorithm is mostly used to find the bottleneck arcs by calculating flow network, and does not presents the minimum cut. This paper suggests an algorithm that simply includes the maximum capacity vertex to adjacent set S or T and finds the minimum cut without obtaining flow network in advance. On applying the suggested algorithm to 13 limited graphs, it can be finds the minimum cut value $_{\min}c$(S, T) with simply and correctly.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2007.11a
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• pp.73-78
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• 2007

Recently, Townhouse has emerged as a blue ocean of real estate market in Korea. In designing town houses, which are luxurious suburban houses centered around the capital area, the construction companies are using 'designer marketing' in which they hire interior designers and architects and express various styles of design in the interior space of the town houses. Therefore, this study examined the unit-family cases of Korean townhouses and analyzed the expression characteristics of design in the interior space of the town houses built after 2000 in terms of their spatial, morphological, material, and color aspect. "The extensibility of space" and "variableness of space" seem to have the same meaning, but they turned out to be not related to each other due to the particularity of houses. "The extensibility of space" turned out to show its characteristics via "the use of transparent materials." "Minimal form" utilizes the unified "achromatic and simple colors" to emphasize the simplicity and in some cases, highlights the use of original colors. The interior space of the townhouses expresses the traditional or heterosexual oriental image through "the use of natural materials," and they point out the "oriental form" through the controlled beauty expressed by using oriental components and "achromatic and simple colors."

• Korean Institute of Interior Design Journal
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• v.14 no.4 s.51
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• pp.62-69
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• 2005

This study shows the present conditions and the appraisal of Public-Toilet in ammusement park of Kangwon-Do. The areas of Public-Toilets are various from over $30m^2\;to\;230m^2$ and the construction costs are also various. The exterior designs aim at Provincial characteristics, traditional images, or modem minimal styles. The floor plans are usually symmetric forms by rectangular or circular spaces. There are some laws and manuals from related association to regulate Public-Toilet. By appraising with these laws and manuals we can notice that there are many problems to improve in Public-Toilet. As the survey, we can find that the unpreparedness of the cognition equipment about whether someone uses the public-toilet has most frequency in related laws. And by the laws about multipurpose toilet, the insufficiency of the accessing space to the chamber pot has most frequency. By the manual of related association, there are much more indications - for example, the unpreparedness of wind protection room or etiquette bell, so on - than by related laws. For the improvement of the culture In Public-Toilet, we should not only improve the related laws, but also activate the deliberation about the appropriate planning in Public-Toilet.

• Korean Journal of Remote Sensing
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• v.1 no.1
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• pp.5-27
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• 1985

A hill-sliding technique was devised to extract Gaussian clusters from the multivariate probability density estimates of sample data for the first step of iterative unsupervised classification. The underlying assumption in this approach was that each cluster possessed a unimodal normal distribution. The key idea was that a clustering function proposed could distinguish elements of a cluster under formation from the rest in the feature space. Initial clusters were extracted one by one according to the hill-sliding tactics. A dimensionless cluster compactness parameter was proposed as a universal measure of cluster goodness and used satisfactorily in test runs with Landsat multispectral scanner (MSS) data. The normalized divergence, defined by the cluster divergence divided by the entropy of the entire sample data, was utilized as a general separability measure between clusters. An overall clustering objective function was set forth in terms of cluster covariance matrices, from which the cluster compactness measure could be deduced. Minimal improvement of initial data partitioning was evaluated by this objective function in eliminating scattered sparse data points. The hill-sliding clustering technique developed herein has the potential applicability to decomposition of any multivariate mixture distribution into a number of unimodal distributions when an appropriate diatribution function to the data set is employed.