• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.293-296
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• 2008

The member deflection is one of the most important considerations for the serviceability evaluation of reinforced concrete (RC) structures, and the concept of the effective moment of inertia has been generally used for its estimation. However, the actual service load applied on an existing RC beam may not be easily obtained, for which the estimation of beam deflection by existing methods can be difficult work. Therefore, based on the close relationships between cracks and deflection in a RC beam, this study proposed a method to estimate the deflection of RC beams directly from the condition of cracks not using the actual loads acting on the member as its input data. The proposed method extensively utilized the relationships among sums of crack widths, average strains, and curvatures, and modification factors obtained from regression analysis were also introduced to improve its accuracy. The deflections of members were successfully estimated by the proposed method independent from applied loads, which was also easy to apply compared to the existing methods based on the effective moment of inertia. This new method, however, has limitations in its applicability in that it is less accurate than the existing methods because the magnitude of acting load is not involved in the estimation process of member deflection, and that it requires the measurement of crack widths along the whole length of a member.

• Applied Chemistry for Engineering
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• v.21 no.2
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• pp.200-204
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• 2010

Surface properties are important for determining the functions and uses of materials. So modification of materials with polymer thin films has emerged as an important method to control the physical and chemical properties of the surface layer. We report a simple and effective method to photochemically attach thin polymeric layers to solid surface without chemical derivatization of the substrate and/or the polymer. The system is based on a photoreactive poly(4-vinylpyridine) (P4VP) thin film which is formed on the $SiO_{2}$ surface via spin coating. This substrate is then covered with another polymer film that is reacted with the benzyl radical moieties by UV irradiation. As a result of photochemical reaction, a thin layer of the later polymer is covalently bound to the surface of P4VP. Unbounded polymer is removed by sonication. The thickness of the attached film is a function of the irradiation time and the molecular weight of the polymer. Spatially defined polymer thin films can be fabricated by way of photolithography.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.49 no.3
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• pp.81-88
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• 2012

In this paper, we propose a novel speech enhancement algorithm for effective noise suppression in various noisy environments. In the proposed method, to result in improved decision performance for speech and noise segments, local speech absence probability (LSAP, local SAP) based on Teager energy of noisy speech is used as the feature parameter for voice activity detection (VAD) in each frequency subband instead of conventional LSAP. In addition, The presented method utilizes global SAP (GSAP) derived in each frame as the weighting parameter for the modification of the adopted TE operator to improve the performance of TE operator. Performances of the proposed algorithm are evaluated by objective test under various environments and better results compared with the conventional methods are obtained.

• Economic and Environmental Geology
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• v.30 no.5
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• pp.459-467
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• 1997

In order to examine the primary trends and characteristics of geological lineaments along the southwestern boundary of Okcheon zone, we carried out the analysis of geological lineament trends over six selected sub-areas using Landsat-5 TM images and digital elevation model. The trends of lineaments is determined by a minimum variance method, and the resulting geological lineament map can be obtained through generalized Hough transform. We have corrected look direction biases reduces the interpretability of remotely sensed image. An approach of histogram modification is also adopted to extract drainage pattern specifically in alluvial plains. The lineament extracting method adopted in this study is very effective to analyze geological lineaments, and that helps estimate geological trends associated various with the tectonic events. In six sub-areas, the general trends of lineaments are characterized NW, NNW, NS-NNE, and NE directions. NW trends in Cretaceous volcanic rocks and Jurassic granite areas may represent tension joints that developed by rejuvenated end of the Early Cretaceous left-lateral strike-slip motion along the Honam Shear Zone, while NE and NS-NNE trends correspond to fault directions which are parallel to the above Shear Zone. NE and NW trends in Granitic Gneiss are parallel to the direction of schitosity, and NS-NNE and NE trends are interpreted the lineation by compressive force which acted by right-lateral strike-slip fault from late Triassic to Jurassic. And in foliated Granite, NE and NNE trends are coincided with directions of ductile foliation and Honam Shear Zone, and NW-NNW trends may be interpreted direction of another compressional foliation (Triassic to Early Jurassic) or end of the Early Cretaceous tensional joints. We interpreted NS-NNE direction lineation is related with the rejuvenated Chugaryung Fault System.

• Journal of Powder Materials
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• v.10 no.6
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• pp.406-414
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• 2003

In order to produce good wear resistance powder metallurgy Al-Si alloys with high strength, addition of glass forming elements of Ni and Ce in $Al_{81}$Si$_{19}$ alloy was examined using SEM, TEM, tensile strength and wear testing. The solubility of Si in aluminum increased with increasing Ni and Ce contents for rapidly solidified powders. These bulk alloys consist of a mixed structure in which fine Si particles with a particle size below 500 nm and very fine A1$_3$Ni, A1$_3$Ce compounds with a particle size below 200 nm are homogeneously dispersed in aluminum matrix with a grain size below 600 nm. The tensile strength at room temperature for $Al_{81}$Si$_{19}$, $Al_{78}$Si$_{19}$Ni$_2$Ce$_{0.5}$, and $Al_{76}$Si$_{19}$Ni$_4$Ce$_1$ bulk alloys extruded at 674 K and ratio of 10 : 1 is 281,521, and 668 ㎫ respectively. Especially, $Al_{73}$Si$_{19}$Ni$_{7}$Ce$_1$ bulk alloy had a high tensile strength of 730 ㎫. These bulk alloys are good wear-resistance bel ter than commercial I/M 390-T6. Specially, attactability for counterpart is very little, about 15 times less than that of the I/M 390-T6. The structural refinement by adding glass forming elements such as Ni and Ce to hyper eutectic $Al_{81}$Si$_{19}$ alloy is concluded to be effective as a structural modification method.d.tion method.

• Archives of Plastic Surgery
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• v.35 no.6
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• pp.687-691
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• 2008

Purpose: An inverted nipple presents both cosmetic and functional problems. It is a source of repeated irritation and inflammation, and interferes with nursing. In addition, its abnormal appearance may cause psychological distress. With consideration of its underlying pathophysiologic components and severity, a number of techniques have been introduced for correction of this anomaly. The diversity of techniques indicates the lack of a good, sustainable, and durable solution for this quite common problem. We report our method as an alternative solution for correcting of the inverted nipple. Methods: From August 2003 to November 2007, 273 nipples in 147 patients were treated. 126 patients had bilateral inverted nipples. Patient age at the operation ranged from 21 to 63 years(mean age, 34 years). All nipples were congenital anomaly. 45 nipples were graded as grade I, 179 nipples as II, and 49 nipples as III. In the our study, we made some modification to the classic purse-string suture: (1) twice purse-string suture: (2) excision of diamond-shaped skin at the nipple neck: (3) buried suture of the breast parenchyma at the nipple base: (4) some timely release of retraction using Bovie's electrocautery dissection at inner surface of the nipple neck. Results: The operation time averaged 15 minutes. The mean follow-up period ranged from 3 to 48 months, with an average of 8.4 months. There were no complications associated with the surgery, such as infection, hematoma, permanent sensory disturbance, or total nipple necrosis except temporary sensory loss in 9 cases, partial nipple necrosis in 7 cases, and recurred inversion in 15 cases. All patients except recurred inversion were satisfied with their results. Conclusion: We believe that our modified purse-string suture is a reliable, simple, safe, and effective method for correcting the inverted nipple.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.6
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• pp.1-9
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• 2015

Transverse steel bars are used in the plastic hinge zone of columns to insure adequate confinement, prevention of longitudinal bar buckling and ductile behavior. Fabrication and placement of rectangular hoops and cross-ties in columns are difficult to construct. Details of reinforcement for rectangular section require a lot of rectangular hoops and cross-ties. In this paper, to solve these problems, the new lateral confinement method using oblong hoop is proposed for the transverse confinement of the flared column. It can be the alternative for oblong cross-section and flared column with improved workability and cost-efficiency. The final objectives of this study are to suggest appropriate oblong hoop details and to provide quantitative reference data and tendency for seismic performance or damage assessment based on the drift levels such as residual deformation, elastic strain energy. This paper describes factors of seismic performance such as ultimate displacement/drift ratio, displacement ductility, response modification factor, equivalent viscous damping ratio and effective stiffness.

• Journal of the Korea Society of Computer and Information
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• v.10 no.4 s.36
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• pp.181-189
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• 2005

Due to grammatical similarities, even a one-to-one mapping between Korean and Japanese morphemes can usually result in a high quality Korean-to-Japanese machine translation. So most of Korean-to-Japanese machine translation are based on a one-to-one mapping relation. Most of Korean '-hada' verbs, which consist of a noun and '-hada', also correspond to Japanese '-suru' verbs, which consist of a noun and '-suru', so we generally use one-to-one mapping relation between them. However, the applications only by one-to-one mapping may sometimes result in incorrect Japanese correspondences in some cases that Korean 'hada' verbs don't correspond to Japanese 'suru' verbs. In these cases, we need to handle a noun and '-hada' as one translation unit. Therefore, this paper examined the characteristics of Korean '-hada' verb and proposed transfer rules of Korean 'hada' verb, applying for various states of input sentences such as discontinuity due to inserted words between a noun and '-hada', passivization, and modification of '-hada' verb. In an experimental evaluation, the proposed method was very effective for handling '-hada' verb in a Korean-to-Japanese machine translation, showing high quality of translation results.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.1
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• pp.1-11
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• 2012

Human thermal sensation based on a human energy balance model was analyzed in the study areas, the Changwon and Nanaimo sites, on clear days during thesummer of 2009. The climatic input data were air temperature, relative humidity, wind speed and solar and terrestrial radiation. The most effective factors for human thermal sensation were direct beam solar radiation, building view factor and wind speed. Shaded locations had much lower thermal sensation, slightly warm, than sunny locations, very hot. Also, narrow streets in the Nanaimo site had higher thermal sensation than open spaces because of greater reflected solar radiation and terrestrial radiation from their surrounding buildings. Calm wind speed also produced much higher thermal sensation, which reduced sensible and latent heat loss from the human body. By adopting climatic factors into landscape architecture, the human thermal sensation analysis method promises to help create thermally comfortable outdoor areas. The method can also be used for urban heat island modification and climate change studies.

• Molecules and Cells
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• v.46 no.9
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• pp.538-544
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• 2023

The formation of uniform vitreous ice is a crucial step in the preparation of samples for cryogenic electron microscopy (cryo-EM). Despite the rapid technological progress in EM, controlling the thickness of vitreous ice on sample grids with reproducibility remains a major obstacle to obtaining high-quality data in cryo-EM imaging. The commonly employed classical blotting process faces the problem of excess water that cannot be absorbed by the filter paper, resulting in the formation of thick and heterogeneous ice. In this study, we propose a novel approach that combines the recently developed nanowire self-wicking technique with the classical blotting method to effectively control the thickness and homogeneity of vitrified ice. With simple procedures, we generated a copper oxide spike (COS) grid by inducing COSs on commercially available copper grids, which can effectively remove excess water during the blotting procedure without damaging the holey carbon membrane. The ice thickness could be controlled with good reproducibility compared to non-oxidized grids. Incorporated into other EM techniques, our new modification method is an effective option for obtaining high-quality data during cryo-EM imaging.