• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1997.11a
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• pp.384-391
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• 1997

The hazard assessment in which the potential hazard factors In the buildings are investigated and the scale of the hazard is analyzed should be performed first in order to prevent personal and material damages due to building fire. In this study, the building fire hazard are assessed using 822-item checklist, for the qualitative evaluation of which the main factors are classified into 10 items, yielding 100 scale points with some weighting. It is shown that present model is applicable for the assessment of all general buildings through the examination of the suitability of assessment model by actual assessment of existing building. Also, the checklist is prepared in itemized questionnaire form for easy assessment of building fire hazard. Therefore, the present model will be helpful for those working in fire prevention, who are suffering from the lack of manifest evaluation model for the fire prevention assessment so far in Korea.

• Journal of Sericultural and Entomological Science
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• v.29 no.2
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• pp.7-14
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• 1987

Extensive studies were undertaken to analyze the genetic basis of economically important quantitative characters in the silkworm by diallel crosses of four inbred lines differing widely in silk yielding ability. Some differences between the reciprocal corsses were detected in cocoon weight, cocoon shell weight, cocoon filament length and cocoon filament weight in case the parental lines were greatly differenent each other in silk yielding ability. The general combining ability (GCA) varied with the inbred lines and M242, a Chieese sexlimited larval marking variety showed high GCA value in the economic characters, such as cocoon yield, cocoon weight, cocoon filament length and weight, and raw silk percentage. The highest heterosis effect, about 13% to 14% was seen in cocoon and raw silk yield and it was low in cocoon reelability and raw silk percentage with less than 1%. It is advisable to improve highly heritable quantitative characters such as larval duration, cocoon shell weight, cocoon filament length and raw silk percentage by means of selection, and to select single crosses with high heterosis effect for cocoon weight and cocoon yield which show overdominance. Genetic correlation should be considered when more than two characters are targets for improvement and selecting high cocoon shell weight is effective to breed high silk yielding varieties. It is difficult to improve cocoon reelability because of low heritability (0.11) and its negative correlation with cocoon-silk quality.

• Vascular Specialist International
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• v.34 no.4
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• pp.94-102
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• 2018

Purpose: Aim of this study is to report real-life experience on the treatment of peripheral artery disease (PAD) with a specific drug-coated balloon (DCB), and to evaluate potential prognostic factors for outcomes. Materials and Methods: This is a retrospective study reporting outcomes in patients with PAD who were treated with the Lutonix DCB during a four-year period. Major outcomes included: all-cause mortality, amputation, clinical improvement, wound healing and target lesion revascularization (TLR). Mean follow-up was $24.2{\pm}2.3$ months. Results: Overall, 149 patients (mean age: $68.6{\pm}8.3$ years; 113 males) were treated, either for intermittent claudication (IC) (n=86) or critical limb ischemia (CLI) (n=63). More than half the target lesions (n=206 in total) were located in the superficial femoral artery and 18.0% were below-the-knee lesions. CLI patients presented more frequently with infrapopliteal (P=0.002) or multilevel disease (P=0.0004). Overall, all-cause mortality during follow-up was 10.7%, amputation-free survival was 81.2% and TLR-free survival was 96.6%. CLI patients showed higher all-cause mortality (P=0.007) and total amputation (P=0.0001) rates as well as lower clinical improvement (P=0.0002), compared to IC patients. Coronary artery disease (CAD), gangrene and infrapopliteal disease were found to be predictors for death whereas CLI and gangrene were found to be predictors for amputation, during follow-up. Conclusion: PAD treatment with Lutonix DCBs seems to be an efficient and safe endovascular strategy yielding promising results. However, CAD, gangrene, CLI and infrapopliteal lesions were found to be independent predictors for adverse outcomes. Larger series are needed to identify additional prognostic factors.

• Korean Journal of Medicinal Crop Science
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• v.16 no.1
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• pp.9-15
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• 2008

Immune-potentiation of Chicorium endivia L. were investigated on follows extracts associated with ultrasonification process at 60 kHz and showed the highest promotion of human B and T cell growth, about $10{\sim}20%$ compared to the control. The secretion of TNF-${\alpha}$ and IL-6 was also enhanced by the addition $(0.5mg/m{\ell})$ of the extracts. NK cell activation was Improved up to 1.37 times higher than the control, through adding extracts. It was also found that extracts from C. endivia L. could yield higher nitric oxide production from macrophage than Lipopolysaccaharides (LPS). It can be concluded that, in general, the extracts treated with ultrasonification has higher immune activity than others, possibly by higher yielding immune-modulatory activity than conventional extraction process. The optimum condition for the extraction of C. endivia L. is ethanol extraction at $60{\sim}100^{\circ}C$ associated with ultrasonification.

• Fire Science and Engineering
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• v.10 no.4
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• pp.29-36
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• 1996

The hazard assessment in which the potential hazard factors in the buildings are investigated and the scale of the hazard is analyzed should be performed first in order to prevent personal and material damages due to building fire. In this study, the building fire hazard are assessed using 822-item checklist, for the qualitative evaluation of which the main factors are classified into 10 items, yielding 100 scale points with some weighting. It is shown that present model is applicable for the assessment of all general buildings through the examination of the suitability of assessment model by actual assessment of existing building. Also, the checklist is prepared in itemized questionnaire form for easy assessment of building fire hazard. Therefore, the present model will be helpful for those working in fire prevention, who are suffering from the lack of manifest evaluation model for the fire prevention assessment so far in Korea.

• 제어로봇시스템학회:학술대회논문집
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• 1994.10a
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• pp.364-368
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• 1994

Algebraic matrix Riccati equations of the form, FP+PF$^{T}$ -PRP+Q=0. are analyzed with reference to the stability of closed-loop system F-PR. Here F, R and Q are n * n real matrices with R=R$^{T}$ and Q=Q$^{T}$ .geq.0 (nonnegative-definite). Such equations have been playing key roles in optimal control and filtering problems with R .geq. 0. and also in the solutions of in H$_{\infty}$ control problems with R taking the form R=H$_{1}$$^{T}$ H$_{1}$-H$_{2}$$^{T}$ H$_{2}$. In both cases an existence of stabilizing solution, i.e. the solution yielding asymptotically stable closed-loop system, is an important problem. First, we briefly review the typical results when R is of definite form, namely either R .geq. 0 as in LQG problems or R .leq. 0. They constitute two extrence cases of Riccati to the cases H$_{2}$=0 and H$_{1}$=0. Necessary and sufficient conditions are shown for the existence of nonnegative-definite or positive-definite stabilizing solution. Secondly, we focus our attention on more general case where R is only assumed to be symmetric, which obviously includes the case for H$_{\infty}$ control problems. Here, necessary conditions are established for the existence of nonnegative-definite or positive-definite stabilizing solutions. The results are established by employing consistently the so-called algebraic method based on an eigenvalue problem of a Hamiltonian matrix.x.ix.x.

• Strategy21
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• s.43
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• pp.225-247
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• 2018

The purpose of this study is to find out a significant influence of continental strategy theories on the development of maritime strategy theories. For this purpose, I examined similar and different parts of each theories and their implications when applied to different environment. In details, Chapter 2 deals with how continental strategy and maritime strategy theories are similar and different in general. In Chapter 3, I look into how Karl Clausewitz's theory that has been quoted the most by military strategy theorists had influenced over the theory of Julian Corbett, one of the representative English maritime strategy theorists. In Chapter 4, I study how the theory of Alfred Mahan that has also been quoted the most among the theories of maritime strategy had been influenced by Antoine-Henri Jomini's theory. And in Chapter 5, their contemporary implications and conclusions are drawn. According to my findings, unbelievably, the theories of maritime strategy had been influenced by existing continental strategy theories very much. Many similarities are found between them. However, at the same time, a large part of them is found significantly different from original ones especially when used to reflect the maritime distinctiveness. This means that the past maritime strategy theories and stored experience also wield influence, in many ways, yielding out much better ones in terms of applicability to changing environment. Therefore, devising new strategies with creative attitude using knowledges and experiences from both other fields and past ones is the virtue required for maritime strategists.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.807-814
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• 2004

Land seismic reflection survey has been increasingly demanded in various civil engineering works because of its own ability to delineate layers, water table, to detect cavities or fracture zones, to estimate seismic velocities of each layer. However, our shallow subsurface structures are very complex. The relatively thin layer(mostly soil) to the wavelength directly followed by a basic rock with high impedance used to generate complicated surface waves, kind of channel waves with high amplitude that is dominate in entire seismograms and hence the useful reflection events will be almost hopelessly immersed in the undesired surface waves. Thus, it would seem that the use of traditional seismic survey could not be likely to provide in itself a satisfactory information about our exploration targets. This paper hence introduces an efficient measuring strategy illustrating a properly controlled arrangement of the vertical single force sources commonly used, yielding a very sharply elongated form of P-energy with a minimum of S radiation energy, what we call, P-beam source. Abundant experiments of physical modeling showed that in that way the surface waves could be enormously reduced and the reflection events would be additive and thus reinforced. Examples of field data are also illustrated. The contribution of P-beam source will be great in civil engineering area as well as in general geological exploration area.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.4
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• pp.409-416
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• 2009

Standard procedures for a fracture toughness testing require very severe restrictions for the specimen geometry to eliminate a size effect on the measured properties. Therefore, the used standard fracture toughness data results in the integrity assessment being irrationally conservative. However, a realistic fracture in general structures, such as in nuclear power plants, may develop under the low constraint condition of a large scale yielding with a shallow surface crack. In this paper, cleavage fracture toughness tests have been made on side-grooved PCVN (precracked charpy V-notch) type specimens (10 by 10 by 55 mm) with various crack depths. The constraint effects on the crack depth ratios were evaluated quantitatively by the developed scaling method using the 3-D finite element method. After the fracture toughness correction from scaling model, the statistical size effects were also corrected according to the standard ASTM E 1921 procedure. The results were evaluated through a comparison with the $T_0$ of the standard CT specimen. The corrected $T_0$ for all of the PCVN specimens showed a good agreement to within $5.4^{\circ}C$ regardless of the crack depth, while the averaged PCVN $T_0$ was $13.4^{\circ}C$ higher than the real CT test results.

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.673-679
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• 2005

Urban conditions such as underground facilities and ambient noises due to cultural activity restrict the application of conventional geophysical techniques in general. We used the linear array microtremor technique which uses these noises as strong energy source. The result parameter of the survey is shear wave velocity profile which had been applied as an fundamental information for the determination of the rock support type in tunnel design. This study was the first case in Korea which utilized a surface geophysical technique yielding successful result in urban area especially under the existing rail ways. The quantitative relation between the shear wave velocity from this method and the rock mass rating(RMR) determined from the inspection of the cores recovered from the same boreholes showed high statistical relationship. These correlations were then used to relate the shear-wave velocity to RMR along the entire profile.