• Structural Engineering and Mechanics
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• v.56 no.4
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• pp.625-648
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• 2015

Modern super-tall buildings are more sensitive to strong winds. The evaluation of wind loads for the design of these buildings is of primary importance. A direct monitoring of wind forces acting on super-tall structures is quite difficult to be realized. Indirect measurements interpreted by inverse techniques are therefore favourable since dynamic response measurements are easier to be carried out. To this end, a Kalman filtering based inverse approach is developed in this study so as to estimate the wind loads on super-tall buildings based on limited structural responses. The optimum solution of Kalman filter gain by solving the Riccati equation is used to update the identification accuracy of external loads. The feasibility of the developed estimation method is investigated through the wind tunnel test of a typical super-tall building by using a Synchronous Multi-Pressure Scanning System. The effects of crucial factors such as the type of wind-induced response, the covariance matrix of noise, errors of structural modal parameters and levels of noise involved in the measurements on the wind load estimations are examined through detailed parametric study. The effects of the number of vibration modes on the identification quality are studied and discussed in detail. The made observations indicate that the proposed inverse approach is an effective tool for predicting the wind loads on super-tall buildings.

• Journal of Korean Academy of Nursing
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• v.29 no.6
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• pp.1192-1207
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• 1999

The purpose of this study was to clarify the dynamic relationships among risk factors of arteriosclerosis and to develop and examine a model which could explain this relationship clearly. Data were collected from medical records of 400 male clients who visited a university hospital located in Inchon for physical examinations, from May 1996 to December 1996. Data were analyzed using the LISREL (Linear Structural Relationship) 8 program. To test the fitness of the hypothesized model, chi-square, RMSR (root mean square residual), GFI (goodness of fit index), CN (critical number) and Q-plot were used. Most of the fitness measurements, except the chi-square showed that the hypothesized model complimented the real data. According to the results, there were trends that obesity and hyperlipidemia were prevalent in heavier smokers, higher alcohol intakers, and groups who excercised less. Also, hypertension was more prevalent in older age, higher alcohol intaker, and higher serum lipid level groups. In contrast to the hypothesis, alcohol intake did not significantly affect serum lipid levels. This might be due to the serum lipid measurements (total cholesterol and trigryceride) used in this study to estimate hyperlipidemia. The direct effect of smoking on hypertension was not significant. However, the total effect of smoking on the hypertension was significant since indirect effects of smoking on hypertension, such as obesity and hyperlipidemia, were significant. The total effect of obesity on hypertension was significant since the indirect effect of obesity on hypertension via hyperlipidemia was significant, although the direct effect of smoking on hypertension was not significant. The degree of explaining hyperlipidemia with smoking, exercise, and obesity was high (60%), however, the degree of explaining obesity with age, smoking, alcohol intake, and exercise was very low (7%). On the basis of these results, high risk factors of arteriosclerosis such as hypertension, hyperlipidemia, or obesity are either directly or indirectly correlated each other. Therefore, it is difficult to predict outcomes for increasing or decreasing the risk factors by simply modulating a factor. Smoking, alcohol, and exercise both directly and indirectly affected major risk factors of arteriosclerosis. Therefore, correcting these variables is required to decrease risk factors. Finally, the relationship among other risk factors which have been known to be related with arteriosclerosis (diet, stress or hereditary) should be clarified in further studies.

• Journal of Ocean Engineering and Technology
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• v.17 no.6
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• pp.83-90
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• 2003

This paper presents an underwater hybrid navigation system for a semi-autonomous underwater vehicle (SAUV). The navigation system consists of an inertial measurement unit (IMU), and a Doppler velocity log (DVL), accompanied by a magnetic compass. The errors of inertial measurement units increase with time, due to the bias errors of gyros and accelerometers. A navigational system model is derived, to include the scale effect and bias errors of the DVL, of which the state equation composed of the navigation states and sensor parameters is 20. The conventional extended Kalman filter was used to propagate the error covariance, update the measurement errors, and correct the state equation when the measurements are available. Simulation was performed with the 6-d.o,f equations of motion of SAUV, using a lawn-mowing survey mode. The hybrid underwater navigation system shows good tracking performance, by updating the error covariance and correcting the system's states with the measurement errors from a DVL, a magnetic compass, and a depth sensor. The error of the estimated position still slowly drifts in the horizontal plane, about 3.5m for 500 seconds, which could be eliminated with the help of additional USBL information.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.11
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• pp.969-974
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• 2003

HgGa$_2$S$_4$ single crystals were grown by the chemical transport reaction method. The HgGa$_2$S$_4$ single crystal crystallized into a defect chalcopyrite structure (I 4). The lattice constants of the single crystal were found to be a = 5.635 $\AA$ and c = 10.473 $\AA$. The direct and indirect optical energy gaps were found to be 2.84eV and 2.78eV, respectively. Photoluminescence peaks of HgGa$_2$S$_4$ single crystal were observed at 2.37 eV, 2.18 eV, and 1.81 eV. In the single crystal, the donor level of 0.25 eV, the acceptor levels of 0.97 eV and 0.41 eV were obtained by TSC, PICTS, and absorption measurements. The photoluminescence peaks were analyzed to relate to the indirect conduction band, the donor level, and the acceptor levels.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.05c
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• pp.47-52
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• 2004

$HgGa_2S_4$ single crystals were grown by the chemical transport reaction method. The $HgGa_2S_4$ single crystal crystallized into a defect chalcopyrite structure $(I\bar{4})$. The lattice constants of the single crystal were found to be a=5.635 ${\AA}$ and c=10.473 ${\AA}$. The direct and indirect optical energy gaps were found to be 2.84 eV and 2.78 eV, respectively. Photoluminescence peaks of $HgGa_2S_4$ single crystal were observed at 2.37 eV, 2.18 eV, and 1.81 eV. In the single crystal, the donor level of 0.25 eV, the acceptor levels of 0.97 eV and 0.41 eV were obtained by TSC, PICTS, and absorption measurements. The photoluminescence peaks were analyzed to relate to the indirect conduction band, the donor level, and the acceptor levels.

• Journal of electromagnetic engineering and science
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• v.17 no.2
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• pp.76-85
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• 2017

We investigate the indirect-fed magnetic resonant wireless power transfer (MR-WPT) system for wireless charging for mobile devices by rearranging the loops and coils. Conventional MR-WPT is difficult to apply to consumer electronic products because of the arrangement of the resonators. In addition, there are restrictions for charging using a wireless technology, which depend on the circumstances of the usage scenarios. For practical applications, we analyzed the transfer efficiency of the MR-WPT system with various combinations and positions of resonators. Three rearranged configurations (Out-Out, Out-In, In-In) have been considered and experimentally investigated using hollow pipe loops and wire copper coils. There were four types of loops and two types of coils; each one had a different diameter and thickness. The results of the measurements show that the trends of the transfer efficiencies for the three configurations were similar. A transfer efficiency of 82.5% was achieved at a 35-cm distance between the 60-cm diameter transmitter (Tx) and receiver (Rx) coils.

• PNF and Movement
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• v.19 no.1
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• pp.97-104
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• 2021

Purpose: The human body can experience a variety of injuries. As a result, it may be difficult to directly treat the damaged area. In such a case, indirect treatment is required. Indirect treatment is typically PNF treatment. Morphological changes in muscle have been confirmed through several previous studies; however, few studies have analyzed neurological changes. Therefore, the purpose of this study was to determine how irradiation during resistance exercise using a diagonal pattern effects neurological excitability. Methods: Electromyography was performed on 13 healthy adults. A compound muscle action potential (CMAP) was obtained through a median motor nerve conduction velocity test, which was conducted before and after performing the irradiation exercise and general exercise. Results: Compared to baseline measurements, there was no significant difference in the latency of the irradiation exercise and general exercise. The amplitude of the CMAP measured after the irradiation exercise was significantly higher than after general exercise. Conclusion: Neurological excitability was high in irradiation during resistance exercise using a diagonal pattern. When clinically direct treatment is difficult, it is thought that irradiation can be used indirectly as a technique to induce nerve excitability.

• Journal of The Korean Astronomical Society
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• v.36 no.spc1
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• pp.83-91
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• 2003

There are terrestrial signatures of the solar activity cycle in ice core data (Ram & Stoltz 1999), but the variations in the sun's irradiance over the cycle seem too small to account for the signature (Lean 1997; Goode & Dziembowski 2003). Thus, one would expect that the signature must arise from an indirect effect(s) of solar activity. Such an indirect effect would be expected to manifest itself in the earth's reflectance. Further, the earth's climate depends directly on the albedo. Continuous observations of the earthshine have been carried out from Big Bear Solar Observatory since December 1998, with some more sporadic measurements made during the years 1994 and 1995. We have determined the annual albedos both from our observations and from simulations utilizing the Earth Radiation Budget Experiment (ERBE) scene model and various datasets for the cloud cover, as well as snow and ice cover. With these, we look for inter-annual and longer-term changes in the earth's total reflectance, or Bond albedo. We find that both our observations and simulations indicate that the albedo was significantly higher during 1994-1995 (activity minimum) than for the more recent period covering 1999-2001 (activity maximum). However, the sizes of the changes seem somewhat discrepant. Possible indirect solar influences on the earth's Bond albedo are discussed to emphasize that our earthshine data are already sufficiently precise to detect, if they occur, any meaningful changes in the earth's reflectance. Still greater precision will occur as we expand our single site observations to a global network.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.11
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• pp.1495-1506
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• 2004

This study was attempted to clarify the characteristics of elderly women's foot shape by examining the various measurements of women over 60 years old as compared with those of women in twenties considered as reference group. The subjects were 321 elderly women and 181 young women. Their right feet were measured directly and indirectly by using scanner and digital camera. The anthropometric measurements were composed of 62 items. They were measured during the months of July and August in 2001. As a result of comparing actual measurements of foot between the two groups, it was found that the elderly women tended to have shorter and lower foot than those among the young women. Among the elderly women, in addition, it was revealed that many deformities related to toes or legs led to the toes concentrated to the central axis of feet resulting in relatively steeper lateral angle of toe, and the heels and legs slanting forwards. As a result of comparing index values of foot between the groups, the elderly women's foot had the relatively wide width and low height in comparison with the length, showing more elliptical flattening than those of the young women. And, the width of the inside was wider than that of the outside, and the toe width was relatively short in comparison with the foot width resulting in severe deformities on the toes or the central axis of foot. Therefore, it was found that there were several deformities including flat foot or deformed toes among elderly women. It is expected that the characteristics of elderly women's foot shown in the results mentioned above will be used as the basic data in designing the footwear for elderly women.

• 한국노년학
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• v.34 no.2
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• pp.409-429
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• 2014

The purpose of this study was to examine the ambivalence of adult children to their elderly parents. 410 adult children who married and having alive mother or father were included. First, direct measurement for asking ambivalence was developed and the relationship between direct and indirect measurements of ambivalence was tested. Next, the influences of parental, children, and relational characteristics on ambivalence were examined. Nine items were selected as direct measurement of ambivalence through the exploratory factor analysis and item response theory. The relationship between direct measure and indirect measure was from .543(p<.000) to r=.625(p<.000) based on gender and generation. The effects of indirect ambivalence on conflict was bigger than direct one for both sons and daughters and the influences of direct measurement on intimacy and relational satisfaction were bigger than indirect one. In case of sons, caregiving obligation was the biggest predictor on ambivalence for mothers and value differences was on ambivalence for fathers. For daughters, age of self was the biggest predictor on ambivalence for mothers and age of fathers was the one for fathers. These results were discussed on the meanings of ambivalence for elderly mothers and fathers in Korea comparing with Chinese and Western cultures.