• Structural Engineering and Mechanics
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• v.20 no.3
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• pp.363-380
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• 2005

The cable tension plays an important role in the construction, assessment and long-term health monitoring of cable structures. The cable vibration equation is nonlinear if cable sag and bending stiffness are included. The engineering implementation of a vibration-based cable tension evaluation is mostly carried out by the simple taut string theory. However, the simple theory may cause unacceptable errors in many applications since the cable sag and bending stiffness are ignored. From the practical point of view, it is necessary to have empirical formulas if they are simple and yet accurate. Based on the solutions by means of energy method and fitting the exact solutions of cable vibration equations where the cable sag and bending stiffness are respectively taken into account, the empirical formulas are proposed in the paper to estimate cable tension based on the cable fundamental frequency only. The applicability of the proposed formulas is verified by comparing the results with those reported in the literatures and with the experimental results carried out on the stay cables in the laboratory. The proposed formulas are straightforward and they are convenient for practical engineers to fast estimate the cable tension by the cable fundamental frequency.

• Journal of the Korea Fashion and Costume Design Association
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• v.17 no.3
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• pp.207-224
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• 2015

Protective clothing for riot policewomen is worn by policewomen to protect their body at suppressing a riot. Plastic guards of Nylon 66 material are attached to the base of E.V.A. Foam material. Protective clothing for riot policewomen consists of a jacket, guards for arms and legs, upper arm braces, and thigh pads. This study was aimed to develop the base pattern of the jacket to protect the torso and to improve the body suitability and the adaptability to movements of protective clothing for riot policewomen. Since current protective clothing worn by riot policewomen is manufactured with the same design of protective clothing for riot policemen, the body suitability and the adaptability to movements are not very satisfactory for policewomen who has different body structure than from riot policemen. Therefore, the purpose of this study is to reflect the body size and characteristics of riot policewomen and develop the base pattern of protective clothing with better body suitability and adaptability to movements. In this respect, amount and place of dots on the jacket were differently designed, made and evaluated by fitting test. The base with the best evaluation was selected as the final experiment clothing to demonstrate its superiority compared with the existing protective clothing.

• KIEAE Journal
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• v.15 no.4
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• pp.37-43
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• 2015

Purpose : The study applied control strategy to reduce through optimal control and operation of pump by applying control on variable speed to the circulation pump of HVAC system in the office building. The study has the purpose to review validity of control on variable speed as ESMs(Energy Saving Measures) and establish the control technology on variable speed pump. The study performed reduction analysis of building energy and economic evaluation of pump through energy effectiveness control strategy of HVAC system. Method: The study sought possible reduction through energy control strategy which can provide proper flow fitting to building load by applying control on variable speed pump. The study applied control strategy to reduce through pressure differential set-point control and operation of pump by applying control on variable speed to the circulation pump of HVAC system in the office building. Result : The results showed that about 16-35% of pump energy could be saved by using these optimal control strategies. In the result of analysis on 10 years life cycle cost of analysis on payback period of initial investment pump, variable speed pump control showed 5.1 years.

• The Korean Journal of Community Living Science
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• v.24 no.1
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• pp.119-132
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• 2013

This study aims to understand potential gender differences in the association between job characteristics and job satisfaction among older workers. The data are from 506 males and 202 females older than 55 from the first wave of the Korean Longitudinal Study of Ageing(KLoSA). Analyses focused on examining gender differences in the influences of subjective evaluation of work characteristics measured with education and skill fits of the work, work demands, customary early retirement, as well as more objective job conditions assessed with insurances by the employer, work hours, and salary on job satisfaction. Regression analyses revealed that female workers showed higher job satisfaction while job characteristics worked differently between genders to affect job satisfaction. For males, fitting the job with education and job demands were determining factors of job satisfaction, while the job with skills and work hours appeared to be significant factors for females. Results suggest that opportunities to utilize older workers' human capital and flexible working hours, especially for females workers would be helpful in promoting older adults' employment and satisfaction about their work.

• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2471-2476
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• 2014

The aim of the present study is to explore the possibility of utilizing loess for the adsorption of total phosphorous (T-P) and total nitrogen (T-N) in water. Batch adsorption studies were performed to evaluate the influences of various factors like initial concentration, contact time and temperature on the adsorption of T-P and T-N. The adsorption data showed that loess is not effective for the adsorption of T-N. However, loess exhibited much higher adsorption capacity for T-P. At concentration of $1.0mgL^{-1}$, approximately 97% of T-P adsorption was achieved by loess. The equilibrium data were fitted well to the Langmuir isotherm model. The pseudo-second-order kinetic model appeared to be the better-fitting model because it has higher $R^2$ compared with the pseudo-first-order and intra-particle kinetic model. The theoretical adsorption equilibrium $q_{e,cal}$ from pseudo-second-order kinetic model was relatively similar to the experimental adsorption equilibrium $q_{e,exp}$. The thermodynamic parameters such as free energy ${\Delta}G$, the enthalpy ${\Delta}H$ and the entropy ${\Delta}S$ were also calculated.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2005.03a
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• pp.18-25
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• 2005

Stochastic ground-motion method is adopted to simulate horizontal PGA values for the offshore Uljin earthquake recorded at nationwide seismic stations. For this purpose, the Fourier spectra are calculated at every stations based on comprehensive results of wave propagation and site effect which were previously revealed through inversion process applied to large accumulated spectral D/B. In addition, the apparent source spectrum of the offshore Uljin earthquake is estimated by removing the path and site response from the observed spectra. The distance dependent time-duration model is revised by iteratively fitting the PGA values generated by using the raw spectra data to the observed PGA data. The stochastic ground-motion method predicts the observed PGA values within a error of ${\sigma}_{log10}=0.1$. Transfer functions of a site relative to another site are estimated based on the error residual of the inversion results and used to convert PGA values at multiple stations to expected PGA values at a reference station of TJN. The converted PGA values can be used as basic data to evaluate the ground-motion attenuation relations developed for seismic hazard analysis that concerns the large damaging earthquakes.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.1
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• pp.91-102
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• 2001

The purpose of this study is to suggest a individually fitted slacks pattern in order to help ourselves prepared for the days of the order-based production like the EC in the apparel industry. A pattern was designed to make the personal fit improved based on the present study and the analysis of the measurements and the body shapes. The main characteristics of this newly designed slacks pattern are as follows. To improve fitting, the pattern requires more detailed data such as front and back waist arc, front and back hip arc, hip depth, the gradient of hip. And for personal fitted pattern, knee girth was established in the proportion to the hip girth and the crotch curve was adjusted to the measurements after drawing and the side seam curve was changed according to the front hip type and the ease in waist and hip was established by the percentage. Slacks pattern was developed into an automatic drafting program. Through the sensory evaluation for the appearance and moving fitness, newly designed slacks pattern was turned out to be improved in personal fit espacially for the body type out of the average.

• Journal of KSNVE
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• v.9 no.1
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• pp.60-69
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• 1999

In the first paper of this research$^{(1)}$. a new time series method. directional ARMAX (dARMAX) model-based approach. was proposed for rotordynamics identification. The dARMAX processes complex-valued signals, utilizing the complex modal testing theory which enables the separation of the backward and forward modes in the two-sided frequency domain and makes effective modal parameter identification possible. to account for the dynamic characteristics inherent in rotating machinery. In this second part. an evaluation of its performance characteristics based on both simulated and experimental data is presented. Numerical simulations are carried out to show that the method. a complex time series method. successfully implements the complex modal testing in the time domain. and it is superior in nature to the conventional ARMAX and the frequency-domain methods in the estimation of the modal parameters for isotropic and weakly anisotropic rotor systems. Experiments are carried out to demonstrate the applicability and the effectiveness of the dARMAX model-based approach, following the proposed fitting strategy. for the rotordynamics identification.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.12
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• pp.1690-1694
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• 2002

Genetic parameters were estimated for birth weight and weaning weight from three year (1991-1993) data totalling 1100 records of 25 rams to 205 ewes of Indigenous Sabi flock maintained at Grasslands Research Station in Zimbabwe. AIREML procedures were used fitting an Animal Model. The statistical model included the fixed effects of year of lambing, sex of lamb, birth type and the random effect of ewe. Weight of ewe when first joined with ram was included as a covariate. Direct heritability estimates of 0.27 and 0.38, and maternal heritability estimates of 0.24 and 0.09, were obtained for birth weight and weaning weight, respectively. The total heritability estimates were 0.69 and 0.77 for birth weight and weaning weight, respectively. Direct-aternal genetic correlations were high and positive. The corresponding genetic covariance estimates between direct and maternal effects were positive and low, 0.25 and 0.18 for birth weight and weaning weight, respectively. Responses to selection were 0.8 kg and 0.14 kg for birth weight and weaning weight, respectively. The estimated expected correlated response to selection for birth weight by directly selecting for weaning weight was 0.26. Direct heritabilities were moderate; as a result selection for any of these traits should be successful. Maternal heritabilities were low for weaning weight and should have less effect on selection response. Indirect selection can give lower response than direct selection.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.8B
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• pp.760-770
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• 2002

Transmit diversity is an efficient diversity technique to improve performance and spectrum efficiency in wireless communication . Coding scheme designed for the transmit diversity is called space-time coding. In this paper, we propose a training structure to apply the transmit diversity to improve the performance of IEEE802.11a OFDM systems. Based on this training structure, we propose a channel estimation scheme using curve fitting. Also we compare and evaluate the performance of space-time codes. The performance of both diversity using space-time codes and channel estimation scheme is investigated by computer simulation in quasi-static 2-ray rayleigh fading environment.