• Steel and Composite Structures
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• v.27 no.6
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• pp.691-702
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• 2018

This paper presents experimental and analytical results of fiber reinforced polymer (FRP) confined steel tubular columns under transverse impact loads. Influences of applied impact energy, thickness of FRP jacket and impact position were discussed in detail, and then the impact responses of FRP confined steel tubes were compared with bare steel tubes. The test results revealed that the FRP jacket contributes to prevent outward buckling deformation of steel at the clamped end and inward buckling of steel at the impact position. For the given applied impact energy, specimens wrapped with one layer and three layers of FRP have the lower peak impact loads than those of the bare steel tubes, whereas specimens wrapped with five layers of FRP exhibit the higher peak impact loads. All the FRP confined steel tubular specimens displayed a longer duration time than the bare steel tubes under the same magnitude of impact energy, and the specimen wrapped with one layer of FRP had the longest duration time. In addition, increasing the applied impact energy leads to the increase of peak impact load and duration time, whereas increasing the distance of impact position from the clamped end results in the decrease of peak impact load and the increase of duration time. The dynamic analysis software Abaqus Explicit was used to simulate the mechanical behavior of FRP confined steel tubular columns, and the numerical results agreed well with the test data. Analytical solution for lateral displacement of an equivalent cantilever beam model subjected to impact load was derived out. Comparison of analytical and experimental results shows that the maximum displacement can be precisely predicted by the present theoretical model.

• KIEAE Journal
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• v.11 no.2
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• pp.83-90
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• 2011

This study has observed 12 parks (20 spots) in Seoul to know the number of users, gender, age groups for the units of 30 minutes from 06:00AM till 10:00PM. According to the systematic characteristic of the surveyed outdoor exercise place, the details of their users during the summer time were analyzed from the objective viewpoint. Major results of analysis are as follows: Firstly, in case of the riverside of the Han River 07:00AM marked a mini peak and 21:00PM reached the peak, and in case of sub-stream neighborhoods, 21:00PM showed only one peak. On the other hand, in case of neighborhood parks (including pocket park) no peak time was noticeable. Secondly, in case of the riverside of the Han River and the neighborhoods of sub-streams, people used the exercise equipment remarkably at night, and in case of neighborhood parks people used the exercise equipment a little bit more in the morning than in the afternoon. Thirdly, in case of nights in summer the riverside of the Han River was preferred by men, while the neighborhoods of sub-streams were preferred by women and the neighborhood parks showed no difference in the number of users among men and women. Fourthly, differently from men, women do not regard the exercise so seriously as men and their purpose of using outdoor exercise place is to use their leisure time mostly with their family members or neighbors, and women prefer light and comfortable exercises. Fifthly, in summer even those who like to exercise a lot like to exercise in the morning to avoid summer heat. Therefore, provision of shades in summer is very important.

• The Korean Journal of Nuclear Medicine
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• v.24 no.1
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• pp.24-28
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• 1990

Various urodynamic studies have been used in patients with bladder outlet obstruction in order to evaluate the degree of obstruction, the results of therapy and postprostatectomy conditions. Radionuclide urodynamic study was performed in 27 patients with bladder outlet obstruction and 30 normal controls. The parameters evaluated were voiding time, 50% voiding time, average flow rate, peak flow rate, corrected peak flow rate, ejection fraction of the bladder and residual urine. Voiding time, 50% voiding time and residual urine of patients were significantly larger than controls and average flow rate, Peak flow rate, peak corrected flow rate and ejection fraction were significantly lower in patients. This method was noninvasive procedure for determining of voiding parameters and it avoids the extraexamination needs to determine the residual urine.

• Journal of The Korean Society of Agricultural Engineers
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• v.52 no.4
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• pp.1-10
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• 2010

In this study, two estimation equations for preparing stream data for distributed storm runoff model were developed by analyzing the nonlinear relation between upstream flow-length and stream width, and between upstream flow-length and stream bed-slope. The equations for stream cell were tested in Chungjudam watershed (6,661 $km^2$) using KIMSTORM. Six storm events occurring between 2003 and 2008 were selected for the model calibration and verification before the test of equations. The average values of the Nash-Sutcliffe model efficiency (ME), the volume conservation index (VCI), the relative error of peak runoff rate (EQp), and the difference of time to peak runoff (DTp) were 0.929, 1.035, 0.037, and -0.406 hr for the calibrated four storm events and 0.956, 0.939, 0.055, and 0.729 hr for the two verified storm events respectively. The estimation equations were tested to the storm events, and compared the flood hydrograph. The test result showed that the estimation equation of stream width reduced the peak runoff and delaying the time to peak runoff, and the estimation equation of stream bed-slope showed the opposite results.

• The Korean Journal of Applied Statistics
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• v.27 no.5
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• pp.843-853
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• 2014

Accurate electricity demand forecasting for daily peak load is essential for management and planning at electrical facilities. In this paper, we rst, introduce the several time series models that forecast daily peak load and compare the forecasting performance of the models based on Mean Absolute Percentage Error(MAPE). The results show that the Reg-AR-GARCH model outperforms other competing models that consider Cooling Degree Day(CDD) and Heating Degree Day(HDD) as well as seasonal components.

• Journal of the Semiconductor & Display Technology
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• v.18 no.1
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• pp.48-52
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• 2019

The blue emitting fluorescence of $SrAl_{12}O_{19}:Ce_{0.09}{^{3+}}$, $Eu_{0.01}{^{2+}}$ phosphor includes two kinds of independent energy transfer mechanism through electric multipole interactions between donor and acceptor ions. The first energy transfer takes place between the $Ce^{3+}$ ion and the $Eu^{2+}$ion which strongly depends on the concentration $Eu^{2+}$ions. The second energy transfer occurs between the $Ce^{3+}$ ion and the $O_{Me}-Ce^{3+}$ complexes. Both energy transfer mechanisms of blue emitting peak at 410 nm were investigated by fitting of Gaussian functions. The result shows that the peak at 410 nm is two overlapping emissions originated by $Eu^{2+}$ions and $O_{Me}-Ce^{3+}$ complexes and as time elapses $Eu^{2+}$peak remains whereas $O_{Me}-Ce^{3+}$ related peak disappears.

• Nuclear Engineering and Technology
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• v.53 no.12
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• pp.4179-4188
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• 2021

This study identifies efficient earthquake intensity measures (IMs) for seismic performances and fragility evaluations of the reactor containment building (RCB) in the advanced power reactor 1400 (APR1400) nuclear power plant (NPP). The computational model of RCB is constructed using the beam-truss model (BTM) for nonlinear analyses. A total of 90 ground motion records and 20 different IMs are employed for numerical analyses. A series of nonlinear time-history analyses are performed to monitor maximum floor displacements and accelerations of RCB. Then, probabilistic seismic demand models of RCB are developed for each IM. Statistical parameters including coefficient of determination (R²), dispersion (i.e. standard deviation), practicality, and proficiency are calculated to recognize strongly correlated IMs with the seismic performance of the NPP structure. The numerical results show that the optimal IMs are spectral acceleration, spectral velocity, spectral displacement at the fundamental period, acceleration spectrum intensity, effective peak acceleration, peak ground acceleration, A95, and sustained maximum acceleration. Moreover, weakly related IMs to the seismic performance of RCB are peak ground displacement, root-mean-square of displacement, specific energy density, root-mean-square of velocity, peak ground velocity, Housner intensity, velocity spectrum intensity, and sustained maximum velocity. Finally, a set of fragility curves of RCB are developed for optimal IMs.

• Science of Emotion and Sensibility
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• v.11 no.2
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• pp.235-244
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• 2008

This study is to develop automatic extraction system of continuous blood pressure using ECG (Electrocardiogram) and PPG(Photoplethysmography) for u-health care technology. PTT (Pulse Transit Time) was determined from peak difference between ECG and PPG and its inverse made to get blood pressure. Since the peaks were vulnerable to be contaminated from noise and variation of amplitude, this study developed the adaptive algorithm for peak calculation in any noise condition. The developed method of the adaptive peak calculation was proven to make the standard deviations of PPT decrease to 28% and the detection of noise increase to 18%. Also, the correlation model such as blood pressure = -0.044 $\cdot$ PTT + 133.592 has successfully been determined for predicting the continuous pressure measured without using cuff but with using PPG and ECG, only.

• Journal of Acupuncture Research
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• v.21 no.2
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• pp.183-203
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• 2004

Objective : Tension-type headache is the most common headache. The objective of this study is to find the clinical manifestation of tension-type headache and correlation with autonomic bioelectric response. Methods : This observation was carried out on 60 patients with tension-type headache. We used headache questionnaire and the Autonomic Bioelectric Response recoder(ABR-2000) for this study. Results : 1. Distribution of sex & age : male : female=5 : 7, 50s&60s group (28.3%) 2. Duration of onset : over 5years(50%), over one years(83.4%) 3. Causes of illness : stress(58.3%), severe fatigue(53.5%), tension(33.3%) 4. Time of attack : irregular(56.7%), day time(16.7%) 5. Pattern of pain: heavy(31 people), stiffness of occipital region (27 people) tightening around the head(25 people) 6. Curve : 40%, 56.7%, 35.0% SL(Slope low) at peak 1, 2, 3/ SH&SI not found 7. Regulation : 16.7% RR(Regulation reverse) at peak 1, 25% RH(Regulation high) at peak 2, 15% RR(Regulation reverse) at peak 3 8. Graph : Activity-60.0%, 70.0%, 63.3% lowered reaction(L, LR, L!) at peak 1, 2, 3 Reactivity-83.3%, 95.0%, 93.3% lowered reaction at peak 1, 2, 3 Conclusion : We find tension-type headache has remarkable relativeness with autonomic bioelectric response.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.6
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• pp.2398-2421
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• 2020

In third world countries like Pakistan, the production of electricity has been quickly reduced in past years due to rely on the fossil fuel. According to a survey conducted in 2017, the overall electrical energy capacity was 22,797MW, since the electrical grids have gone too old, therefore the efficiency of grids, goes down to nearly 17000MW. Significant addition of fossil fuel, hydro and nuclear is 64.2%, 29% and 5.8% respectively in the total electricity production in Pakistan. In 2018, the demand crossed 20,223MW, compared to peak generation of 15,400 to 15,700MW as by the Ministry of Water and Power. Country faces a deficit of almost 4000MW to 5000MW for the duration of 2019 hot summer term. Focus on one aspect considering Demand Side Management (DSM) cannot oversea the reduction of gap between power demand and customer supply, which eventually leads to the issue of load shedding. Hence, a scheduling scheme is proposed in this paper called RPSMDSM that is based on selection of those appliances that need to be only Turned-On, on priority during peak hours consuming minimum energy. The Home Energy Management (HEM) system is integrated between consumer and utility and bidirectional flow is presented in the scheme. During peak hours of electricity, the RPSMDSM is capable to persuade less power consumption and accomplish productivity in load management. Simulations show that RPSMDSM scheme helps in scheduling the electricity loads from peak price to off-peak price hours. As a result, minimization in electricity cost as well as (Peak-to-Average Ratio) PAR are accomplished with sensible waiting time.