• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.257-260
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• 2008

The heat resistance of steel materials tends to weaken due to its high heat transfer properties, which might result in deteriorated strength because of rapidly rising temperature on surface in a fire. Particularly in case of CFT column that bears tensile stress of the structure on its external steel members, a numerical analysis on deterioration of strength and variation of stress shall be first carried out to ensure the structure will have sufficient fire resistance. In the study, based on values obtained from the high temperature material property test of steel materials and concrete, the test to forecast the fire behavior of CFT column was conducted using a finite element analysis method (ABAQUS). An Analysis in a bid to predict the heat transfer and the behavior characteristics by varying the strength of the concrete filled to the range of 40MPA and 50MPA was carried out. As a result of analysis of CFT column on condition of 180-minute exposure under the standard fire condition, 123mm of strain appeared with 40MPA model, while 91mm contraction with 50MPA model.

• Journal of Korean Academy of Nursing Administration
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• v.14 no.3
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• pp.229-240
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• 2008

Purpose: To develop the patient classification system based on the resource utilization for reimbursement of long-term care hospitals in Korea. Method: Health Insurance Review & Assessment Service (HIRA) conducted a survey in July 2006 that included 2,899 patients from 35 long-term care hospitals. To calculate resource utilization, we measured care time of direct care staff (physicians, nursing personnel, physical and occupational therapists, social workers). The survey of patient characteristics included ADL, cognitive and behavioral status, diseases and treatments. Major category criteria was developed by modified delphi method from 9 experts. Each category was divided into 2-3 groups by ADL using tree regression. Relative resource use was expressed as a case mix index (CMI) calculated as a proportion of mean resource use. Result: This patient classification system composed of 6 major categories (ultra high medical care, high medical care, medium medical care, behavioral problem, impaired cognition and reduced physical function) and 11 subgroups by ADL score. The differences of CMI between groups were statistically significant (p<.0001). Homogeneity of groups was examined by total coefficient of variation (CV) of CMI. The range of CV was 29.68-40.77%. Conclusions: This patient classification system is feasible for reimbursement of long-term care hospitals.

• Journal of the Korean Ceramic Society
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• v.42 no.7 s.278
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• pp.490-496
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• 2005

The electrical properties and stability of the varistors composed of ZnO-Pr$_{6}$O$_{11}$-CoO-Cr$_{2}$O$_{3}$-Dy$_{2}$O$_{3}$ system were investigated with sintering time in the range of 1$\~$3 h at 1350$^{\circ}C$ . As the sintering time was increased, the varistor voltage and leakage current increased, but the nonlinear exponent decreased. The varistors sintered for 1 h exhibited excellent nonlinearity, with a nonlinear exponent of 55.3 and a leakage current of 0.1 $\mu$A, whereas presented relatively low stability. The varistors sintered for 2 h exhibited not only high nonlinear exponent of 46.3, low leakage current of 0.3 $\mu$A, low dielectric dissipation factor of 0.0431, but also the highest stability, in which the variation rates of varistor voltage, nonlinear exponent, leakage current, dielectric constant, and dielectric dissipation factor were -3.0$\%$, -4.1$\%$, +3056.2$\%$, +5.1$\%$, and -12.5$\%$, respectively, after DC accelerated aging stress state of 0.95 V$_{1ma}$/150$^{\circ}C$/24 h. On the whole, the nonlinearity and stability of these varistors are greatly affected by the sintering time.

• Journal of Korean Society of Transportation
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• v.33 no.1
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• pp.90-99
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• 2015

The climate of Korea has clear rainy and dry season due to seasonal wind. In general, The rainy season in Korea is from early summer through to early fall. And precipitation accounted for more than half of the total annual rainfall in this period. This study is aiming to analysis of variation in saturation flow rate at signalized intersection during rainfall. The range of spatial is urban signalized intersections in Seoul and temporal is rainfall or ideal condition in daylight. Traffic data are collected through CCTV of Seoul Metropolitan Police Agency, and on-site video recordings directly. Weather condition data are collected from the Korea Meteorological Administration. In addition, the value of saturation headway and saturation flow rate, in rainfall condition, are derived through video frame analysis. As a results of analysis, decrease of saturation flow rate and increase of saturation headway during rainfall were confirmed by comparison with non-rainfall. The higher rainfall rate is, the more decreased saturation flow rate at the intersections. Rainfall rate is divided three area by the results of statistical test, and saturation flow rate decrease 7%, 17%, 21%, respectively.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.08a
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• pp.175-183
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• 2004

In hot strip rolling, a capability for precisely predicting roll force is crucial for sound process control. In the past, on-line prediction models have been developed mostly on the basis of Orowan's theory and its variation. However, the range of process conditions in which desired prediction accuracy could be achieved was rather limited, mainly due to many simplifying assumptions inherent to Orowan's theory. As far as the prediction accuracy is concerned, a rigorously formulated finite element(FE) process model is perhaps the best choice. However, a FE process model in general requires a large CPU time, rendering itself inadequate for on-line purpose. In this report, we present a FE-based on-line prediction model applicable to precision process control in a finishing mill(FM). Described was an integrated FE process model capable of revealing the detailed aspects of the thermo-mechanical behavior of the roll-strip system. Using the FE process model, a series of process simulation was conducted to investigate the effect of diverse process variables on some selected non-dimensional parameters characterizing the thermo-mechanical behavior of the strip. Then, it was shown that an on-line model for the prediction of roll force could be derived on the basis of these parameters. The prediction accuracy of the proposed model was examined through comparison with measurements from the hot strip mill.

• ALGAE
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• v.32 no.3
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• pp.171-179
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• 2017

The strictly freshwater red algal order Batrachospermales has undergone numerous taxonomic rearrangements in the recent past to rectify the paraphyly of its largest genus Batrachospermum. These systematic investigations have led to the description of new genera and species as well as re-circumscription of some taxa. Specimens collected from two locations in the southeastern USA were initially identified as being allied to Batrachospermum sensu lato, but could not be assigned to any recognized species. Representative rbcL (plastid) and COI-5P (mitochondrion) sequences showed these specimens to be similar to each other and not closely matching the previously published sequence data for other Batrachospermum taxa. Comparison of sequence variation and morphology with a broader range of batrachospermalean taxa resulted in the proposal of a new monotypic genus Lympha mucosa gen. et sp. nov. to accommodate these specimens. Lympha mucosa is sister to members of a newly described genus Volatus, but the two genera are easily distinguished based on straight versus curved, twisted or spirally coiled carpogonial branch, respectively. This new taxon has morphological similarities to Batrachospermum sections Turfosa and Virescentia, but can be differentiated based on genetic divergence in rbcL and COI-5P as well as a combination of morphological characters: dense, compressed whorls, axial carposporophytes with a single type of gonimoblast filament; cortication of the main axis closely appressed; and short, straight carpogonial branch arising from the pericentral cell and carpogonia with unstalked, lanceolate trichogynes. This new taxon adds to the freshwater red algal diversity of the southeastern USA, a region already known for biodiversity and high endemism of the aquatic flora and fauna. It is also a relevant new addition to the taxonomic knowledge of the freshwater red algal Batrachospermales.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2019.11a
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• pp.34-35
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• 2019

The objective of this study is to analyze the risk of collision accidents to the VTSOs(Vessel Traffic Service Operators) as small vessels are expanded for monitoring targets. For this purpose, the risks of accidents and quasi-incidents involving small ships in the VTS area were analyzed by the collision risk model(CoRI) from the view-point of VTSOs. In addition, by analyzing risk of whether or not small vessels are included in the monitoring target by CoRI, we will contribute to the preparation of a proper range of the vessel for monitoring taget through various case studies in the future.

• Speech Sciences
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• v.9 no.4
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• pp.187-200
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• 2002

The purpose of the present study is to see in terms of $F_{0}$ variation in Japanese how discourse focus and the lexical word accent interact with each other in realizing overall intonation patterns. Discourse focus causes prosodic restructuring of phrase structures and, as a result, largely affects pitch contours, whereas the lexical word accent is said to delimit the $F_{0}$ into a certain range. Measurement of $F_{0}$ was made of utterances of Japanese sentences to observe behavior of pitch contours with varied focus assignment and lexical accent specifications. The utterances were obtained in question-answer discourse contexts so that in a sentence, either one NP was always focused or no focus was assigned. I set four points for $F_{0}$ measurement; $F_{1s},F_{1m}, F_{2s}$, and $F_{2m}$, two for each noun phrase corresponding to $F_{0}$ at the beginning of the first syllable and that of the vocalic portion of the second syllable in the two NP's. The results of present study were as follows: (1) for all combination of lexical accent types, the $F_{0}$ rise both in NP1 and NP2 are higher when focused than when not focused. (2) NP2 starts a new accentual phrase when focused, showing even higher $F_{0}$ than NP1, the latter of which implies that in forming a new accentual phrase by focusing, catathesis does not seem to take effect on NP2 preceded by accented NP1. (3) unfocused NP2 preceded by unaccented NP1 has higher $F_{0}$ than those preceded by accented NP1.

• Journal of Biomedical Engineering Research
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• v.30 no.6
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• pp.482-488
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• 2009

Conventional devices for transanal endoscopic microsurgery that are currently used clinically for intestine or rectal cancer patients have 40 mm external diameter of rectoscope tube - induces anal damage and long-term postoperative pain for small-sized patients. In this paper, we designed rectum and rectoscope models and calculated the changing trends of operation area of the surgical tools in accordance with the step-by-step variation of design parameters of the rectoscope tube - external diameter, axial length, and distal angle. Using the results of computer simulation, we suggested an optimal set of design parameters that minimizes external diameter of the rectoscope tube and at the same time, maintains similar operation area of the surgical tools compared with commercialized devices (${\geq}\;4274.7mm^2$). The results of the simulation showed that the optimal design parameters were 35 mm external diameter, 100 mm axial length, and $45^{\circ}$ distal angle of the rectoscope tube. This result can be applied to the development of endoscopic microsurgery device that can minimize side effects to the intestine or rectal cancer patients.

• Fisheries and Aquatic Sciences
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• v.11 no.2
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• pp.98-102
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• 2008

Relationships between total length (TL) and fecundity, body weight and fecundity, ovary length and fecundity, and ovary weight and fecundity of hilsa shad, Tenualosa ilisha Hamilton, collected from Kuakata, Patuakhali, Bangladesh, were studied. During the sampling period, the fecundity of hilsa was found to range from 169,000 (fish TL=28.0cm, weight=250g) to 1,088,000 (fish TL=40.5cm, weight=955g) with a mean of $520{\pm}53{\times}1,000$. The number of eggs per gram of ovary for samples collected from the anterior, middle, and posterior regions of the ovary were also recorded, but no significant variation was found among ovary regions at the 5% level of significance. Fecundity increased with fish TL and weight. The regression equations obtained in arithmetic forms of relationships between TL and fecundity (F), body weight (BW) and fecundity, ovary length (OL) and fecundity, and ovary weight (OW) and fecundity were $F=-887,896+40,511{\times}TL(r=0.85)$, $F=67,577+755.44{\times}BW(r=0.85)$, $F=-562,070+87,668{\times}OL(r=0.75)$ and $F=124,815+6,596.7{\times}OW (r=0.84)$, respectively. The relationships between fecundity and TL, body weight, ovary length, and ovary weight were linear, and the 'r' values were highly significant (p<0.01). These results provide valuable data for the restoration of hilsa resources, which are economically important but have shown reduced productivity in nations adjacent to the Bay of Bengal.