• Journal of the Earthquake Engineering Society of Korea
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• v.23 no.4
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• pp.201-209
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• 2019

Response modification factors of school facilities for non-seismic RC moment frames with partial masonry infills in 'Manual for Seismic Performance Evaluation and Retrofit of School Facilities' published in 2018 were investigated in the preceding study. However, since previous studies are based on 2D frame analysis and limited analysis conditions, additional verification needs to be performed to further apply various conditions including orthogonal effect of seismic load. Therefore, this study is to select appropriate response modification factors of school facilities for non-seismic RC moment frames with partial masonry infills by 3D frame analysis. The results are as follows. An appropriate response modification factor for non-seismic RC moment frames with partial masonry infills is proposed as 2.5 for all cases if the period is longer than 0.6 seconds. Also if the period is less than 0.4 seconds and the ratio of shear-controlled columns is less than 30%, 2.5 is chosen too. However, if the period is less than 0.4 seconds and the ratio of shear-controlled columns is higher than 30%, the response modification factor shall be reduced to 2.0. If the period is between 0.4 and 0.6 seconds, then linearly interpolates the response correction factor.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.11
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• pp.3-12
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• 2019

This study is concerning on the Space Modification and Facilities Characteristics of the Busan Exported-cow Quarantine Service Station(1909) before and afrter on the limits of 1945. For on this purpose, National Archives & Records Service(DJB0002115), field survey, documents records and modern aged map were analysised by each period phases, 1909, 1924, 1946, 1951 and now so on. At results on this study is the discovery on the meaning of this placeness, Space Modification and Facilities Characteristics till now before the 120 years ago. And this place has been comprehenive meaning unique dwelling form and almost rarely existing refuge village of Korea War in Korea.

• Management Science and Financial Engineering
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• v.15 no.1
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• pp.1-31
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• 2009

This paper considers the value of warehousing contract under probabilistic demands. We consider a supply chain consisting of a supplier, a retailer and its third-party warehousing partner who provides the warehousing service to the retailer through an outsourcing contract. A typical contract is specified by initial space commitment and modification schedule. The retailer decides the order quantity for the supplier and space commitment for the outsourcing contract. Since there is close relationship between order quantity and space commitment to minimize the total cost including ordering cost, inventory carrying cost, shortage cost, and warehousing cost, we develop an analytical model under probabilistic demands, where the retailer can determine the optimal order size and space commitment level jointly. We found the closed-form optimum for a single-period case and the optimal conditions for a two-period case. To evaluate the value of contract flexibility for the two-period case, we compared the total cost under two policies; one with modification, under which the base commitment can be changed at the start of each period and the other without modification. From results of our numerical analysis, we showed that the modification policy is more cost-effective as the variability of demand increases.

• Korean Journal of Health Education and Promotion
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• v.15 no.2
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• pp.119-142
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• 1998

The purpose of this article is to provide a method of losing weight and early managing risky factors of geriatric diseases by having male and female obese middle school students' participate in behavioral modification and aerobic exercise, foster their own desirable behavioral habit and confidence in solving obesity and continue their living pattern all their life. In order to do this, 64, subjects over 20% obese degree obtained using the standard weight, belonging within 50% range of weight percentage per height(male:32, female:32) were grouped to 4 categories of aerobic exercise therapy, behavioral modification therapy, both therapies combinedly applied and control ones by 8 male and female students allocated to each group respectively, and they were practiced to each program for 12 weeks, and the findings between group were obtained as follows. 1. The male and female middle school students' cholesterol amount of blood fat reduced most in the combinedly performed group of aerobic exercise and behavioral modification therapy. It indicated a statistically significant difference between groups (F(3,56) =9.50, p=.000) and the measurements according to the application period of program as well (F(3,168)=554.94, p=.000). The cholesterol amount per measurement period reduced most between 8 and 12 weeks. 2. The male and female middle school students' high density fat amount increased most in the combinedly performed group of aerobic exercise therapy and behavioral therapy, its descending order of next highest rate was aerobic exercise therapy, behavioral modification therapy and control group. It indicated a statistically significant difference between the distinction of male and female sexes (F(1.56)=13.82. p=.000) and the measurements according to the application period of program (F(3,168) =55.58, p=.000). The high density fatty Quality per measurement period increased most between 8 and 12 weeks. 3. The male and female middle school students' low density fat amount reduced most in the combinedly performed group of aerobic exercise therapy and behavioral modification therapy. It indicated a statistically significant difference between groups (F(3,56)=17.35, p=.000) and the measurements according to the application period of program (F(3,168)=891.14, p=.000. The low density fat amount reduced most between 8 and 12 weeks. 4. The male and female middle school students' neutral fat amount reduced most in the combinedly performed group of aerobic exercise therapy and behavioral modification therapy. It indicated a statistically significant difference between the distinction of sexes (F(1,56)=9.54, p=.003) and groups (F(3,56) =25.57, p=.000) and the measurements according to the application period of program (F(3,168) =566.03, p=.000). The male students indicated the most reduction between 4 and 8 weeks. while the female students between 8 and 12 weeks.

• Structural Engineering and Mechanics
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• v.71 no.4
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• pp.377-390
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• 2019

A method for estimating the floor response spectra (FRS) of elastic structures under earthquake excitations is proposed. The method is established based on a previously proposed direct estimation method for single degree of freedom systems, which generally overestimates the FRS of a structure, particularly in the resonance period range. A modification factor is introduced to modify the original method; the modification factor is expressed as a function of the period ratio and is determined through regression analysis on time history analysis results. Both real and artificial ground motions are considered in the analysis, and it is found that the modification factors obtained from the real and artificial ground motions are significantly different. This suggests that the effect of ground motion should be considered in the estimation of FRS. The modified FRS estimation method is further applied to a 10-story building structure, and it is verified that the proposed method can lead to a good estimation of FRS of multi-story buildings.

• Clinical and Experimental Pediatrics
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• v.59 no.4
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• pp.165-173
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• 2016

Purpose: To identify the effects of modified parenteral nutrition (PN) and enteral nutrition (EN) regimens on the growth of very low birth weight (VLBW) infants. Methods: The study included VLBW infants weighing <1,500 g, admitted to Chungnam National University Hospital between October 2010 and April 2014, who were alive at the time of discharge. Subjects were divided according to 3 periods: period 1 (n=37); prior to the PN and EN regimen being modified, period 2 (n=50); following the PN-only regimen modification, period 3 (n=37); following both PN and EN regimen modification. The modified PN regimen provided 3 g/kg/day of protein and 1 g/kg/day of lipid on the first day of life. The modified EN regimen provided 3.5-4.5 g/kg/day of protein and 150 kcal/kg/day of energy. We investigated growth rate, anthropometric measurements at 40 weeks postconceptional age (PCA) and the incidence of extrauterine growth restriction (EUGR) at 40 weeks PCA. Results: Across the 3 periods, clinical characteristics, including gestational age, anthropometric measurements at birth, multiple births, sex, Apgar score, surfactant use and PDA treatment, were similar. Growth rates for weight and height, from time of full enteral feeding to 40 weeks PCA, were higher in period 3. Anthropometric measurements at 40 weeks PCA were greatest in period 3. Incidence of weight, height and head circumference EUGR at 40 weeks PCA decreased in period 3. Conclusion: Beginning PN earlier, with a greater supply of protein and energy during PN and EN, is advantageous for postnatal growth in VLBW infants.

• Speech Sciences
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• v.3
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• pp.132-147
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• 1998

Previously developed methods for pitch modification have not been based on the voice source model. Therefore, the synthesized speech often sounds unnatural although it may be highly intelligible. The purpose of this paper is to analyze the alteration of a voice source signal with pitch period and to establish the pitch-modification rule based on the result of this analysis. We examine the alteration of the interval of closing phase, closed phase and open phase using the excitation waveform as the pitch increases. In comparison to the previous methods which performed directly on the speech signal, the pitch modification method based on a voice source model shows high intelligibility and naturalness. This study might benefit the application to the speaker identification and the voice color conversion. Therefore the proposed method will provide high quality synthetic speech.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.4
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• pp.353-358
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• 2014

This paper reports a simple, yet effective 1-step surface modification method for stainless steel. Electrochemical etching in dilute Aqua Regia forms hierarchical micro and nanoscale structure on the surface. The surface becomes highly hydrophobic (${\sim}150^{\circ}$) as a result of the etching in terms of static contact angle (CA). However the liquid drops easily pinned on the surface because of high contact angle hysteresis (CAH), which is called a "petal effect": The petal effect occur because of gap between surface microstructures, despite of intrinsic hydrophobicity of the base material. The pore size and period of surface structure can be controlled by applied voltage during the etching. This method can be applied to wide variety of industrial demand for surface modification, while maintaining the advantageous anti-corrosion property of stainless steel.

• Earthquakes and Structures
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• v.14 no.4
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• pp.305-312
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• 2018

Significant research efforts were undertaken to evaluate seismic performance of vertically irregular buildings on flat ground. However, there is scarcity of study on seismic performance of buildings on hill slopes. The present study attempts to investigate seismic behaviour of reinforced concrete irregular stepback building frames with different configurations on sloping ground. Based on extensive regression study of free vibration results of four hundred seventeen frames with varying ground slope, number of story and span number, a modification is proposed to the code based empirical fundamental time period estimation formula. The modification to the fundamental time period estimation formula is a simplified function of ground slope and a newly introduced equivalent height parameter to reflect the effect of stiffness and mass irregularity. The derived empirical formula is successfully validated with various combinations of slope and framing configurations of buildings. The correlation between the predicted and the actual time period obtained from the free vibration analysis results are in good agreement. The various statistical parameters e.g., the root mean square error, coefficient of determination, standard average error generally used for validation of such regression equations also ensure the prediction capability of the proposed empirical relation with reasonable accuracy.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.37 no.3
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• pp.179-186
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• 2024

In this paper, a modification coefficient for equivalent single degree of freedom (SDOF), considering the plasticity range of the member subjected to shock wave type of blast load, was developed. The modification coefficient for the equivalent SDOF was determined through comparison with the analysis of a multi-degree of freedom (MDOF) system. The parameters influencing the equivalent SDOF system analysis were chosen as the boundary conditions of the member and the ratio of the duration of blast load to the natural period of the member. The modification coefficient was calculated based on the elastic load-mass transformation factor. The modification coefficient curve was derived using an elliptical equation to ensure it exists between the upper and lower parameter bounds. Using the modification coefficient on examples with varying cross sections and boundary conditions reduced the SDOF analysis error rate from 15% to 3%. This study shows that using the modification coefficient significantly improves the accuracy of SDOF analysis. The modification coefficient proposed in this study can be used for blast analysis.