• The Journal of Korean Institute of Communications and Information Sciences
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• v.17 no.12
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• pp.1343-1352
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• 1992

This paper presents a new and easy method to obtain the Fourier transforms of the n-th order cosine-pulses whose maximum amplitudes are uniform. The new method is focused on deriving a formula which is recursively related following their orders and can be well applied to some numerical solutions. On the other hand, this method also offers more compact procedures in view of analytical solutions than the conventional methods because the results are consist of the sum of two functions which are easily calculated. Especially, the formula can be represented as a complete recursion by the separation of coefficients originated by the authors and the resulting difference equation is given by the sum of the original 'sinc' functions shifted by some symmetrical factors and multiplied by some constants. The constants are easily decided from the binomial coefficients and the shifting factors from the corresponding exponential differences in the expansion of $(a+b)^n$.

• Journal of the Korea Concrete Institute
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• v.16 no.2 s.80
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• pp.249-260
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• 2004

The longitudinal steel connection of reinforced concrete bridge column is sometimes practically unavoidable, however the current Korean bridge design specifications have no special provisions about lap-splices of longitudinal steel. This paper reports experimental results of a research program investigating the seismic performance of circular RC bridge columns with respect to longitudinal steel connection detailing. Twenty-one circular column specimens were tested under quasi-static test. The columns with the entire longitudinal steel lap-spliced within plastic hinge region show relatively sudden strength degradation and low ductility than the columns with continuous longitudinal steel and the columns with half of longitudinal steel lap-spliced. However, the seismic performance of the column with mechanically connected longitudinal steel is similar to that of the column with continuous longitudinal steel. The final objectives of this study are to suggest appropriate longitudinal reinforcement connection details for the limited ductility design concept and to provide quantitative reference data and tendency for performance or damage assessment based on the performance levels such as cracking, yielding, collapse, etc. Ultimate displacement/drift ratio, displacement ductility, response modification factor, equivalent viscous damping ratio, residual deformation index, and effective stiffness are investigated and discussed in this paper.

• Journal of agricultural medicine and community health
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• v.26 no.2
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• pp.193-203
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• 2001

The purpose of this study was to identify the relationship between depression and physical health of the elderly and to provide fundamental data for programs which improve the health of this population. The subjects were 168 elderly people(55 years and older) who resided at home in Taegu. They were surveyed by interview using a closed- ended questionnaire. The survey was done from September 16 to October 16 in 2000. The instruments used in this study were general characteristics, Short form Geriatric Depression Scale(SGDS), Barthel Index, Muscular skeletal symptoms scale, Northern Illinois University's Health Self Rating Scale. The data were analyzed by using descriptive statistics, t-test, ANOVA, Pearson Correlation Coefficient, multiple regression with SPSS PC 10.0 version for Windows. The findings were as follows: 1. As compared 65-74 years elderly group, 75-84 years group was significantly higher score for depression(F=3.17, p=.026). As compared elderly group who has own spouse, the group who has no own spouse was significantly higher score for depression(t=- 2.44, p=.016). 2. The aged who have more limitation of Activities of Daily Living(ADL)(t=3.93, p=.000), pain of muscular skeletal symptoms(F=5.33, p=.002) and poor perceived health state(F=17.04, p=.000) showed the higher severity of depression than the aged who have not. 3. ADL correlated negatively with depression(r=- .293, p=.000), pain of muscular skeletal symptoms correlated positively(r=.251, p=.001), perceived health status correlated negatively(r=-.522, p=.000). 4. The combination of perceived health status and ADL explained 29.1% of the varience of depression. On the basis of the above findings the following recommendations are made; 1. Developing health programs is needed considering ADL, pain of muscular skeletal symptoms, perceived health status, demographic variables (age, spouse status) which have an significant effects on depression of the elderly. 2. In the following study, the use of the various scale is needed which reflects physical status of the elderly in home.