• Journal of the Korea Concrete Institute
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• v.20 no.2
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• pp.213-219
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• 2008

The purpose of this study is to propose frame analysis method for flat plate slabs having edge beam under lateral loads. Flat plate system is defined as the system only with slab of uniform thickness and column. However, the slab system generally incorporate edge beams at exterior connection in actual design. ACI 318 (2005) allows three methods for conducting flat plate system analysis subjected to lateral loads. There are the finite element method (FEM), the equivalent frame method (EFM), and the effective beam width method (EBWM). Among methods, the EBWM enables us to analyze practically by substituting the actual slab to beam element. In this model, the beam element has a thickness equal to that of the slab, and effective beam width equal to some fraction of the slab transverse width. However, the established EBWM was generally proposed for variables of geometry or stiffness reduction factor and seldom proposed for the effect of edge beams. This study verifies that, in the case of flat plate system having edge beams at exterior connections, the lateral stiffness is considerably larger than without edge beams. Therefore it need to analysis method for considered the effect of edge beams. In this study, an analysis model is proposed for the flat plate system having edge beams under lateral loads by considering the effect of edge beams. To verify the accuracy of proposed model, this study compared results of the proposed EBWM with results of FEM of flat plate systems having edge beams under lateral loads. Also, the proposed approach is compared with experimental results of former research.

• The Journal of the Korea Contents Association
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• v.17 no.9
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• pp.99-106
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• 2017

This study focused on the issue that when a diagnostic detector is found to have a defect, a patient would be exposed to radiation and image quality would be degraded. Though dose analysis, an experiment was conducted to evaluate detector performance as Signal to Noise Ratio (SNR) and Contrast to Noise Ratio (CNR). Absorbed dose, SNR and CNR were measured using a dosimeter and a tissue equivalent phantom. The experiment was conducted to compare whether the dose value shown after being attached to the back side of the phantom matches the dose value attached behind the detector, where in the conditions of skull, chest and abdomen were set at 75 kVp, 25 mAs, 110 kVp, 8 mAs, and 80 kVp, 20 mAs, respectively. As a result, there was a difference in that the dose values attached to the back side of the detector were 0.004 mGy, 0.006 mGy, 0.003 mGy, whereas those of the back side of the phantom were 0.006 mGy, 0.016 mGy, 0.017 mGy. In order to match both values, the condition was increased and SNR and CNR also increased from 88.32, 88.10, 4.09, 1.63, 87.94, 79.97 to 93.87, 93.75, 4.91, 4.03, 92.02, 84.92. Though this study, we found that when a detector is found to have a aging, it shortens the life of equipment and increases the dose of a patient, also the improvement effect of image quality is inadequate.

• Membrane Journal
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• v.13 no.3
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• pp.162-173
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• 2003

The pseudo n-type polyaniline was prepared by doping of camphorsulfonic acid(CSA) and dodecylbenzenesulfonic acid(DBSA) as the dopants in solvent of N-methyl-2-pyrrolidinone(NMP). The dopants in polymer structure was qualitatively analyzed using FT-IR. The influence on electrochemical properties with dopant concentration of PANI film were investigated. The electrochemical characteristics of the n-type PANI electrode that coated on ITO were evaluated by cyclic voltammetry(CV) and AC impedance method. The prepared PANI were confirmed as n-type PANI from FT-IR and CV. The charge transfer resistance of film on PANI/CSA electrode were measured as 1.14{\sim}1.09k{\mu}$by AC impedance. The charge transfer resistance of PANI/DBSA electrode decreased with increasing the mole ratio of DBSA as 27.73{\sim}8.37 k{\mu}$. The double layer capacitance of PANI/CSA electrode was showed almost constant value as $13.47{\sim}14.59 {\mu}F$ and that of PANI/DBSA electrode increased with increasing mole ratio of DBSA from 0.49 to $1.20 {\mu}F$.

• Radiation Oncology Journal
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• v.4 no.2
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• pp.89-97
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• 1986

Using as assay for jejunal crypt stem cell survival, dose-response curves for the reproductive capacity of crypt stem cells of mouse jejunum exposed to multifractionated gamma-ray irradiation (single, 2, 3, 4, 5, 8, 10, 12, and 16 fractions) were analyzed and single-dose survival curve of these cells was constructed. The following conclusion were drawn: 1) Survival curves for higher numbers of dose fractions were displaced to higher dose, and characterized by increasingly shallower slopes. 2) The single-dose survival curve had broad shoulder, Dq=460 cGy, remaining near-exponential over initial dose range 0 to 300 cGy, with initial slope 1Do=474 cGy. 3) At fractionated dose En the range of 180 to 450 cGy, the average recovered dose per fraction interval was approximately $50\%$ of the dose per fraction. 4) The value of $\alpha/\beta$ ratio by using of linear regression analysis for the reciprocal dose plots was 8.3 Gy which lied in the range of 6-14 Gy for early-reacting tissues. 5) The linear-quadratic model for dose-response formula offers valid approximations for at 1 doses to be used in radiotherapy, only two parameters to be determined, and considerable convenience in practical applications.

• Tunnel and Underground Space
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• v.18 no.2
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• pp.98-106
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• 2008

When a tunnel is excavated in a rock mass of poor condition, the adjacent zone of excavation surface may be reinforced by adopting the appropriate methods such as grouting and rock bolting. The reinforced effect can be evaluated by use of various numerical approaches, where the reinforcing elements may be expressed as distinct discretizations or smeared into the equivalent material properties. In this study, a simple numerical method, which can be classified as the latter approach, was developed for the elasto-plastic analysis of a circular tunnel. If a circular tunnel in a Mohr-Coulomb rock mass is reinforced to a finite thickness, the reinforced annulus may have different material properties from the in-situ rock mass. In the proposed elasto-plastic method for assessing the reinforcing effect, Lee & Pietruszczak (2007)'s method is applied to both the reinforced annulus and the outer insitu rock mass of the fictitious tunnel, and then two results are combined by enforcing the compatibility condition. The method were verified through comparing the results with the proposed method and the commercial finite difference code FLAC. When taking the variation of deformation modulus and strength parameters in the reinforced zone into account, the distributions of stress and radial displacement were much different from those obtained with the assumption of homogeneous rock mass.

• Radiation Oncology Journal
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• v.16 no.4
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• pp.399-408
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• 1998

Purpose : This study was designed to demonstrate the potential therapeutic advantage of 3-dimensional (3-D) treatment planning over the conventional 2-dimensional (2-D) approach in patients with carcinoma of the nasopharynx. Materials and Methods : The two techniques were compared both qualitatively and quantitatively for the boost portion of the treatment (19.8 Gy of a total 70.2 Gy treatment schedule) in patient with T4. The comparisons between 2-D and 3-D plans were made using dose statistics, dose-volume histogram, tumor control probabilities, and normal tissue complication probabilities. Results : The 3-D treatment planning improved the dose homogeneity in the planning target volume. In addition, it caused the mean dose of the planning target volume to increase by 15.2$\%$ over 2-D planning. The mean dose to normal structures such as the temporal lobe, brain stem, parotid gland, and temporomandibular joint was reduced with the 3-D plan. The probability of tumor control was increased by 6$\%$ with 3-D treatment planning compared to the 2-D planning, while the probability of normal tissue complication was reduced. Conclusion : This study demonstrated the potential advantage of increasing the tumor control by using 3-D planning. but prospective studies are required to define the true clinical benefit.

• Journal of the Earthquake Engineering Society of Korea
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• v.12 no.1
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• pp.79-87
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• 2008

Seismic performance evaluation of structure requires an estimation of the structural performance in terms of displacement demand imposed by earthquakes on the structure. Incremental Dynamic Analysis(IDA) is a analysis method that has recently emerged to estimate structural performance under earthquakes. This method can obtained the entire range of structural performance from the linear elastic stage to yielding and finally collapse by subjecting the structure to increasing levels of ground acceleration. Most structures are expected to deform beyond the limit of linearly elastic behavior when subjected to strong ground motion. The nonlinear response history analysis(NRHA) among various nonlinear analysis methods is the most accurate to compute seismic performance of structures, but it is time-consuming and necessitate more efforts. The nonlinear approximate methods, which is more practical and reliable tools for predicting seismic behavior of structures, are extensively studied. The uncoupled modal response history analysis(UMRHA) is a method which can find the nonlinear reponse of the structures for ESDF from the pushover curve using NRHA or response spectrum. The direct spectrum analysis(DSA) is approximate nonlinear method to evaluate nonlinear response of structures, without iterative computations, given by the structural linear vibration period and yield strength from the pushover analysis. In this study, the practicality and the reliability of seismic performance of approximate nonlinear methods for incremental dynamic analysis of mixed building structures are to be compared.

• Journal of the Korea Convergence Society
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• v.11 no.12
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• pp.225-232
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• 2020

In This paper examines how "Kamishibai" was used for ideological education of children during the war. "Kamishibai" was proposed by the Ministry of Education as a methodology to "cultivate children's right concentricity. In particular, , which was produced based on a true story, highlights the father's love sent to children by obtaining chocolate wrappers from comrades, and the children's envy for chocolate. Kazuo's interview, saying, "I will succeed my father," showed that he has a continuous personality that comes with another sacrifice. After the Sino-Japanese War, the war situation intensified, and in 1940, a new edict decided to enact the "Army Support Corps". This is a measure to select eligible youth applicants from 15 to 17 years of age, after training for 4 years, and then appoint them to aviation soldiers and sergeants. This is a legal maintenance that can be put into the battlefield at any time according to the trend of the war. Just as Kazuo, a real character in "Chocolate and Soldiers", also became a "boy flight soldier" after his father's death, flying airplanes to boys at the time was also a dream that Japan's great citizens should have. In the , it is suggested that "the father enshrined in Yasukuni" is a great person, and that "I" will also grow and become a "good citizen". In particular, the two brothers in the work show the value of eternal sacrifices in Yasukuni as a typical model of the "great people".

• Geophysics and Geophysical Exploration
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• v.25 no.3
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• pp.99-108
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• 2022

Among induced polarization (IP) methods, spectral IP (SIP) uses alternating current as a transmission source to measure amplitudes and phase of complex electrical resistivity at each source frequency, which disperse with respect to source frequencies. The frequency dependence, which can be explained by a relaxation model such as Cole-Cole model or equivalent models, is analyzed to estimate SIP parameters from dispersion curves of complex resistivity employing multi-objective optimization (MOO). The estimation uses a generic algorithm to optimize two objective functions minimizing data misfits of amplitude and phase based on Cole-Cole model, which is most widely used to explain IP relaxation effects. The MOO-based estimation properly recovered Cole-Cole model parameters for synthetic examples but hardly fitted for the real laboratory measures ones, which have relatively smaller values of phases (less than about 10 mrad). Discrepancies between scales for data misfits of amplitude and phase, used as parameters of MOO method, and it is in necessity to employ other methods such as machine learning, which can deal with the discrepancies, to estimate SIP parameters from dispersion curves of complex resistivity.

• Journal of radiological science and technology
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• v.31 no.2
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• pp.183-188
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• 2008

Aim of this study is to investigate the feasibility of 2D ion chamber array as a substitute of the water phantom system in a periodic Linac QA. For the feasibility study, a commercial ion chamber matrix was used as a substitute of the water phantom in the measurement for a routine QA beam properties. The device used in this study was the I'm RT MatriXX (Wellhofer Dosimetrie, Germany). The MatriXX consists of a 1,020 vented ion chamber array, arranged in $24{\times}24\;cm^2$ matrix. Each ion chamber has a volume of $0.08\;cm^3$, spacing of 0.762 cm. We investigated dosimetric parameters such as dose symmetry, energy ($TPR_{20,10}$), and absolute dose for comparing with the water phantom data with a Farmer-type ionization chamber (FC65G, Wellhofer Dosimetrie, Germany). For the MatriXX measurements, we used the white polystyrene phantom (${\rho}:\;1.18\;g/cm^3$) and also considered the intrinsic layer (${\rho}:\;1.06\;g/cm^3$, t: 0.36 cm) of MatriXX to be equivalent to water depth. In the preliminary study of geometrical QA using MatriXX, the rotation axis of collimator and half beam junction test were included and compared with film measurements. Regarding the dosimetrical QA, the MatriXX has shown good agreements within ${\pm}1%$ compared to the water phantom measurements. In the geometrical test, the data from MatriXX were comparable with those from the films. In conclusion, the MatriXX is a good substitute for water phantom system and film measurements. In addition, the results indicate that the MatriXX as a cost-effective novel QA tool to reduce time and personnel power.