• Proceedings of the Computational Structural Engineering Institute Conference
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• 1990.04a
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• pp.37-43
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• 1990

This paper develops practical models and methods for the assessment of safety and rating of damaged and/or deteriorated bridges by incorporating a system identification technique for the explicit inclusion of the degree of deterioration or damage and of the actual bridge response. And, based on the proposed model, reliability-based rating methods are proposed as LRFR(Load and Resistance Factor Rating) and system reliability-index rating criteria. The proposed limit state model explicitly accounts for the degree of deterioration or damage in terms of the damage and response factors. The damage factor in the paper is proposed as the ratio of the current stiffness to the intact stiffness. Based on the observation and the results of applications to existing bridges, it may be concluded that the proposed rating models, which explicitly account for the uncertainties and the effects of degree of deterioration or damage based on the system identification technique, provide more realistic and consistent safety-assessment and capacity-rating.

• IEMEK Journal of Embedded Systems and Applications
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• v.14 no.2
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• pp.71-78
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• 2019

As the capacity of SSDs rapidly increases, the amount of DRAM to keep a mapping table size in SSDs becomes very huge. To address a Demand-based FTL (DFTL) scheme that caches part of mapping entries in DRAM is considered to be a feasible alternative. However, owing to its unpredictable behaviors, DFTL fails to provide consistent I/O response times. In this paper, we a) analyze a root cause that results in fluctuation on read latency and b) propose a new demand-based FTL scheme that ensures guaranteed read response time with low write amplification. By preventing mapping evictions while serving reads, the proposed technique guarantees every host read requests to be done in 2 NAND read operations. Moreover, only with 25% of a cache ratio, the proposed scheme improves random write performance and random mixed performance by 1.65x and 1.15x, respectively, over the traditional DFTL.

• Structural Engineering and Mechanics
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• v.85 no.1
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• pp.55-64
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• 2023

Energy-based seismic design and evaluation methods are promising to be involved in the next generation design codes. Accordingly, determining the distribution of earthquake input energy demand among floor levels is quite imperative in order to develop an energy-based seismic design procedure. In this paper, peak floor input energy demands are achieved from relative input energy response histories of several reinforced concrete (RC) frames. A set of 22 horizontal acceleration histories selected from recorded near-fault earthquakes and scaled in time domain to be compatible with the elastic acceleration design spectra of Turkish Seismic Design Code are used in time history analyses. The distribution of the computed input energy per mass values and the arithmetic means through the height of the considered RC frames are presented as a result. It is found that spatial distribution of input energy per mass is highly affected by the number of stories. Very practical yet consistent formulation of distributing the total input energy to story levels is achieved, as a most important contribution of the study.

• Animal Systematics, Evolution and Diversity
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• v.39 no.4
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• pp.289-294
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• 2023

We discovered a halacarid mite species, Isobactrus tuberculatus Abé, 1996, inhabiting marine plastic debris on the coast of Jeju Island, Korea. The key characteristics of these Korean specimens were consistent with those in the original description of specimens from Hokkaido, Japan, including the presence of tuberculate membranous cuticles between the anterior and posterior dorsal plates, fusion of the posterior epimeral plates I and II, tibia II with a bipectinate seta, tibiae III and IV each with five setae, and a pair of subgenital setae in females. However, two small morphological differences were noted: the distance between the anterior and posterior dorsal plates was shorter than that in Japanese specimens, and the location of dorsal seta-2 was closer to the anterior dorsal plate in Korean specimens. We herein provide detailed illustrations of I. tuberculatus, based on the Korean specimens, with a brief taxonomic comment on the similarities among allied congeneric species. The genus Isobactrus is first reported in Korea.

• Computational Structural Engineering
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• v.5 no.1
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• pp.119-132
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• 1992

The objective of this study is to perform extensive parametric studies of the lateral-torsional buckling of short 1-beams under repeated loadings, and to gain a further insight into the lateral-torsional beam buckling problem. A one-dimensional geometrically (fully) nonlinear beam model is used, which includes superposed infinitesimal transverse warping deformation in addition to finite torsional warping deformation. A multiaxial cyclic plasticity model is also implemented to better represent cyclic metal plasticity in conjunction with a consistent return mapping algorithm. The general response for the lateral-torsional buckling of short I-beams under repeated loadings is examined through several parametric studies around the standard case : the material yield strength, the yield plateau, the strain hardening, the kinematic hardening, the residual stresses, the load eccentricity with respect to the shear center, the height of the load with respect to the cross-section of the beam, the location of the load along the length of the beam, the dimensions of the cross-section of the beam and the fixity of the supported end remote from the load.

• Clinical and Experimental Pediatrics
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• v.58 no.12
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• pp.484-490
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• 2015

Purpose: To determine the efficacy and safety of oral propranolol as a first-line treatment for superficially located infantile hemangioma (IH) and propose an assessment tool to measure treatment response. Methods: Patients with superficial IH under 1 year of age were prospectively recruited between May 2012 and December 2013 at the Department of Pediatrics of Chungbuk National University Hospital. Propranolol was administered to 12 infants (median age, 3.8 months) while monitoring cardiovascular and adverse metabolic effects. If a patient showed no adverse events, the dosage was gradually increased up to 3 mg/kg/day and maintained for 1 year. We used our own scoring system to assess treatment response using parameters like change in color, and longest diameter, and thickness of the IH. Results: Eleven out of 12 patients completed the protocol with consistent improvement of hemangiomas during therapy. Patients on propranolol showed a more than 50% involution in the first 3 months, with additional steady involution until 1 year. Patients with the highest scores at 1 month maintained their score and showed better responses until treatment termination. The patient with the lowest score at 1 month did not show any further regression and stopped propranolol treatment 4 months after initiation. In two children with recurrences after successful therapeutic regression, propranolol was effective after being reintroduced. Propranolol treatment was not interrupted in any patient due to adverse events. Conclusion: Oral propranolol at 3 mg/kg/day showed a consistent, rapid, and therapeutic effect on superficial IHs without significant adverse events.

• Journal of the Korean Home Economics Association
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• v.38 no.12
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• pp.29-45
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• 2000

The purposes of this study were to determine what factors influence risk perceptions of females and males for milk produced using food-related biotechnology, to test whether risk perceptions or other factors influence self-protection actions and to estimate milk demand response in light of self-protection actions and other economic and demographic factors. The expected utility model was applied to explain the way consumers would take self-protection actions regarding risk perceptions and to drive milk demand. Telephone interviews were conducted and the data were collected from households(females=1,029, males=437) nationwide in the U.S. And the data were analyzed by Heckman two-step method using the software package LIMDEP. Risk perceptions were found to be influenced not by demographic factors but by outrage factors as well as attitudinal factors in both females and males, although some factors were different. In addition, risk perceptions and labeling availability were found to significantly influence self-protection actions in both groups. Furthermore, as an important concern in this study, self-protection action was found to significantly influence milk demand in only male group, implying a consistent behavior of males. Also milk price and household size were found to significantly influence milk demand in both groups. In fact, the results did demonstrate that labeling availability significantly influenced self-protection actions. That is, in markets where labeled laternatives were present, concerned consumers were more likely to self protect by substituting to these products. A policy implication of this result is that labeling food products produced using biotechnology enhances consumer choice. Hence, consumer could express a more accurate demand response and reduce the perceived food safety risk. Furthermore, education for females might be necessary to have a consistent behavior because self-protection action did not significantly influence female's milk demand, though they have greater risk perceptions than males have.

• The Journal of the Korea Contents Association
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• v.18 no.11
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• pp.47-54
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• 2018

The purpose of this study is to explore a difference in crisis between media and parties. This research examined political crisis situation, crisis response, and media coverage using a case. Two main political parties in Korean faced the illegal fund raising case during the 16th presidential election. They used types of crisis response strategies for restoring or maintaining their reputation. This study found that a party's crisis response was consistent with news media, but another party's message was significantly different from news media. Such match or mismatch between a party and news media will influence on public evaluation toward a crisis response. This study has meaningful contribution in that the difference between an organizational crisis response message and news media coverage is significant.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.3
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• pp.213-224
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• 2019

There is an increasing frequency in the occurrence of abnormal weather phenomena such as sharp increases and decreases in temperature. Under these weather conditions, the heading time of rice changes unexpectedly, which poses problems in agriculture. Therefore, we investigated the effect of temperature on the heading response at different growth stages in rice. During the period from transplanting to heading, the plants were subjected to different temperature treatments, each for a 9-day period, to observe the heading response. For the heading date analysis, "heading date" was defined as the number of days from transplanting to the appearance of the first spikelet. We found that the influence of temperature increased in the order of rooting stage, followed by meiosis, early tillering, spikelet differentiation, and panicle initiation stage in all ecological types and cultivars. In particular, unlike the results reported previously, the effect of temperature on heading during the photo-sensitive period was very small. Meanwhile, the influence of temperature on vegetative growth response at different growth stages was not consistent with heading response. These results can be used as basic data for predicting the variation in heading date owing to temperature variation at each growth stage. In addition, we propose that the concept of day length should be included in determining the influence of temperature on the photo-sensitive period.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.14 no.4
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• pp.413-422
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• 2001

In this study, the effect of hydrodynamic masses is investigated in the dynamic characteristics and earthquake response analyses of the submerged HANARO flow tubes. First, the consistent hydrodynamic masses of the surrounding water are obtained by finite element method. Then, modal analyses and response spectrum analyses are performed and verified by comparing the results with those measured from an experiment. Arbitrary cross-sections of submerged structures and boundary conditions of the surrounding fluid can be considered by using the general benefits of a finite element method comparing with the conventional analytical methods. Practical criteria based on parametric studies are proposed to evaluate the dynamic characteristics of HANARO flow tubes including the hydrodynamic masses.