Simultaneous dual-frequency radio observations of S5 0716+714: A search for intraday variability with the Korean VLBI Network

This study aims to search for the existence of intraday variability (IDV) of BL Lac object S5 0716+714 at high radio frequencies for which the interstellar scintillation effect is not significant. Using the 21-meter radio telescope of the Korean VLBI Network (KVN), we present results of multi-epoch simultaneous dual-frequency radio observations. Single-dish observations of S5 0716+714 were simultaneously conducted at 21.7 GHz (K-band) and 42.4 GHz (Q-band), with a high cadence of 30-60 minute intervals.We observed four epochs between December 2009 and June 2010. Over the whole set of observation epochs, S5 0716+714 showed significant inter-month variations in flux density at both the K- and Q-bands, with modulation indices of approximately 19% for the K-band and approximately 36% for the Q-band. In all epochs, no clear intraday variability was detected at either frequency. The source shows monotonic flux density increase in epochs 1 and 3 and monotonic flux density decrease in epochs 2 and 4. In the flux density increasing phases, the flux densities at the Q-band increase more rapidly. In the decreasing phase, no significant flux density difference is seen at the two frequencies. The situation could be different close to flux density peaks that we did not witness in our observations. We find an inverted spectrum with mean spectral indices of -0.57+-0.13 in epoch 1 and -0.15+-0.11 in epoch 3. On the other hand, we find relatively steep indices of +0.24+-0.14 and +0.17+-0.18 in epochs 2 and 4, respectively. We conclude that the frequency dependence of the variability and the change of the spectral index are caused by source-intrinsic effects rather than by any extrinsic scintillation effect.Comment: 6 pages and 4 figures and 4 table

Fragility Analysis of Space Reinforced Concrete Frame Structures with Structural Irregularity in Plan

Because significant damages to structures having structural irregularity in their plans were repeatedly observed during many past earthquakes, there have been great research efforts to evaluate their seismic vulnerability. Although most of the previous studies used simplified structural representations such as one-dimensional or two-dimensional models in the fragility analysis of plan-irregular structures, simple analytical models could not represent true seismic behavior from the complicated nonlinear coupling between lateral and torsional responses as the degree of irregularity increased. For space structures with high irregularity, more realistic representations such as three-dimensional models are needed for proper seismic assessment. However, the use of computationally expensive models is not practically feasible with existing approaches of fragility analysis. Thus, in this study, a different approach is adopted that can produce vulnerability curves efficiently, even with a three-dimensional model. In this approach, an integrated computational framework is established that combines reliability analysis and structural analysis. This enables evaluation of the limit-state faction without constructing its explicit formula, and the failure probability is calculated with the first-order reliability method (FORM) to deal with the computational challenge. Under the integrated framework, this study investigates the seismic vulnerability of space reinforced concrete frame structures with varying plan irregularity. Material uncertainty is considered, and more representative seismic fragility curves are derived with their three-dimensional analytical models. The effectiveness of the adopted approach is discussed, and the significant effect of structural irregularity on seismic vulnerability is highlighted

Effects of Music Therapy on Patients with Cancer Receiving Outpatient Treatment

Patients with cancer often experience anxiety when waiting for diagnostic test results, before receiving treatment, or when informed of a recurrence. Therefore, appropriate interventions are required at each of these stages. This study determines the effects of music therapy with preferred music on anxiety, blood pressure, pulse, and the satisfaction of patients with cancer when receiving outpatient intravenous therapy in a long-term care facility. This quasi-experimental non-equivalent control-group and non-synchronized study was conducted in the outpatient injection room of a long-term care facility in South Korea. This study included 57 patients (divided into experimental and control groups) with female reproductive system/breast or digestive system cancer who received short-term intravenous vitamin C on an outpatient basis. The participants chose from a music selection table for each genre, which was based on the prior research, under the supervision of a professor experienced in music therapy. The participants selected 20 songs to listen to for 1 h while receiving intravenous therapy. The participants were surveyed for state anxiety and satisfaction to confirm the effects of music therapy, and their systolic and diastolic blood pressure and pulse were measured. The state anxiety (U=282, p=.046) and satisfaction (U=262, p=.016) scores of the experimental and control groups revealed significant differences. There were no significant differences in systolic blood pressure (U=311, p=.13), diastolic blood pressure (t=1.88, p=.065), and pulse (t=-0.5, p=.61) between the experimental and control groups. Music therapy is an effective intervention for reducing anxiety and improving satisfaction in patients with cancer when receiving short-term outpatient treatment. However, to generalize these results, a larger sample size of participants is needed with similar types of cancer