• Journal of the Korean Society for Railway
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• v.13 no.3
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• pp.304-308
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• 2010

This paper presents a methodology for identifying track irregularity using a wavelet transfer function. An equivalent wavelet SISO (single-input single-output) transfer function is defined by the measured track geometry and the acceleration data measured at a bogie of a train. All the measured data with various sampling frequencies were rearranged according to the constant 25cm reference recording distance of the track recording vehicle used in the field. Before applying the wavelet transform, measured data were regressed by eliminating those out of the range. The inverse wavelet transfer function is also formulated to estimate track geometry. The closeness of the estimated track geometry to the actual one is evaluated by the coherence function and also by FRF (frequency response function). A track irregularity index is defined by comparing the variance of the estimation error from the intact condition and that from the current condition. A simulation study has been carried out to examine the proposed algorithm.

• Journal of Power Electronics
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• v.17 no.4
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• pp.1048-1057
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• 2017

An indirect matrix converter (IMC) is a modern power generation system that enables a direct ac/ac conversion without the need for any bulky and limited lifetime electrolytic capacitor. This system also allows four-quadrant operation, generation of sinusoidal output voltage waveforms with variable frequency and amplitude, and control of input power factor. This study proposes a pulse-width modulation-based sliding-mode controller to achieve unity input-power factor operation of the IMC independently of the active power exchanged with the grid, as well as a fast dynamic response. The designed equivalent control law determines, at each sampling period, the appropriate q-axis component of the modulated input current to be injected into the grid through the LC input filter. An integral term of the error is included in the expression of the sliding surface to increase the accuracy of the control method. A double space vector modulation method is used to synthesize the direction of the space vector of the input currents as required by the sliding-mode controller and the space vectors of the target output voltages. Simulation and experimental results are provided to show the effectiveness and evaluate the performance of the proposed control method.

• Biomolecules & Therapeutics
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• v.6 no.2
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• pp.213-218
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• 1998

A novel in situ-gelling and mucoadhesive acetaminophen liquid suppository was developed to improve the patient compliance of conventional solid suppository. In this study, acetaminophen liquid suppository, Likipe $n_{R}$, ［aminophen/Poloxamer 407/Poloxamer 188/so4ium alginate (5/15/19/0.6%)] with relation temperature at 30-36 "C and suitable gel strength and bioadhesive force, dissolution pattern similar to conventional solid type suppository, Suspe $n_{R}$, was developed. Furthermore, the bioequivalence of two acetaminophen products was evaluated in 16 normal male volunteers (age 22-27 yr, body weight 56-72 kg) following sidle rectal administration. Test product was Likipe $n_{R}$ suppository (Dong-Wha Pharm. Corp., Korea)and reference product was Suspe $n_{R}$204-212 suppository (Hanmi Pharm. Corp., Korea). Both products contain 125 mg of acetaminophen. Four Suppositories of the test and the reference product were administered to the volunteers, respectively, by randomized two period cross-over study (2$\times$2 Latin square method). The determination of acetaminophen was accomplished using HPLC. Average drug concentrations at each sampling time and pharmacokinetic parameters calculated were not significantly different between two products (p>0.05); the area under the curve to last sampling time (24 hr) (AU $Co_{-2}$4h/) (30.14$\pm$8.64 vs 27.98$\pm$ 6.53 $\mu$g .h/ml), maximum plasma concentration ( $C_{max}$) (3.29$\pm$0.87 vs 3.60$\pm$0.66 $\mu$g/ml) and time to maximum plasma concentration ( $T_{max}$) (2.91 $\pm$0.55 vs 2.69$\pm$0.60 h). The differences of mean AUCo $_{24h}$, C-a. and T-between the two products (7.18%, 9.58% and 7.53%, respectively) were less than 20%. The power (1-7) and treatment difference ($\Delta$) for AU $Co_{24h}$, $C_{max}$ and $T_{max}$ were more than 0.8 and less than 0.2, respectively at $\alpha$=0.1. The confidence limits for AU $Co_{24h}$, $C_{max}$ and $T_{max}$ (-0.81 ~13.55%, -1.56~ 17.60 and -3.81 ~18.87%, respectively) were less than $\pm$ 20% at $\alpha$=0.1. These results suggest that the bioavailability of Likipe $n_{R}$ suppository is not significantly different from that of Suspe $n_{R}$ suppsitory. Therefore, two products are bio-equivalent based on the current results.results.lts.sults.results.lts.

• Journal of Sensor Science and Technology
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• v.14 no.1
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• pp.33-41
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• 2005

For more convenient electrode-electrolyte interface impedance analysis in biosensor, a stand-alone impedance measurement system is required. In our study, we developed a PC-based portable system to analyze impedance of the electrochemical cell using microprocessor. The devised system consists of signal generator, programmable amplifiers, A/D converter, low pass filter, potentiostat, I/V converter, microprocessor, and PC interface. As a microprocessor, PIC16F877 which has the processing speed of 5 MIPS was used. For data acquisition, the sampling rate at 40 k samples/sec, resolution of 12 bit is used. RS-232 with 115.2 kbps speed is used for the PC communication. The square wave was used as stimuli signal for impedance analysis and voltage-controlled current measurement method of three-electrode-method were adopted. Acquired voltage and current data are calculated to multifrequency impedance signal after Fourier transform. To evaluate the implemented system, we set up the dummy cell as equivalent circuit of which was composed of resistor, parallel circuit of capacitor and resistor connected in parallel and measured the impedance of the dummy cell; the result showed that there exist accuracy within 5 % errors and reproduction within 1 % errors compared to output of Hioki LCR tester and HP impedance analyzer as a standard product. These results imply that it is possible to analyze electrode-electrolyte interface impedance quantitatively in biosensor and to implement the more portable high speed impedance analysis system compared to existing systems.

• Journal of Gifted/Talented Education
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• v.14 no.3
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• pp.41-52
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• 2004

No educational provision for the gifted and talented works in a cultural vacuum, and this is as true for out-of-school activities as for what happens in school itself. There is evidence that excellence in children's achievements can come from widely differing special provision or from no special provision at all. Cultural influences affect attitudes as to who might be gifted and talented and what might be done for them. Whatever the size and influence of special centres anywhere, there is always overlap between in-school and out-of-school activities. For all styles of provision, cooperation between the two is a vital aspect of success. The major cultural dichotomy in this field is between the perception, usually found in the Far East that 'most children have gifted potential' and the largely Western view that 'few children have gifted potential'. It is safe to say that children who are selected for aptitude and ability, and who are keen to learn, will get more from special enrichment than those who of equal potential who have not had that experience. But this does not necessarily show the provision as the best possible method for enhancing gifts and talents. In fact, I do not know of a single scientific investigation, either cross-culturally or within one country, which compares any aspect of an out-of-school programme with another. As a result it is hard to say what type of provision would be most appropriate and effective in any given situation. Outcomes are also dependent on the enthusiasm, organisation and money put into any scheme - as well as the way youngsters are chosen for it. Some of the largest and most influential out-of-school American institutions were founded on the psychological understanding of human abilities that was current in the 1920s. These early influences of seeking an IQ cut-off point (or equivalent) to identify the gifted still affect their practice. in addition, the big American Talent Searches so often select youngsters for summer-schools not only by their high-level achievements, but also by their parent's ability to pay the sometimes high fees. Opinions about the identification of the brightest children and consequential educational practice underlie all provision for their education, whether in or outside school hours. Because of cross-cultural differences, it would not seem wise to copy any action directly from one culture to another without recognising these influences and possibly modifying the model. The growing trend around the world is to offer high-level opportunities to as many youngsters as possible, so that no keen learner is turned away without even a change of sampling them.

• Journal of Hospice and Palliative Care
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• v.13 no.4
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• pp.232-242
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• 2010

Purpose: This study was done to investigate effects of foot massage and supportive communication provided by hospice volunteers on depression, anxiety, and mood of cancer patients who are going under intravenous chemotherapy at out patient department (OPD). Methods: A non-equivalent control group non-synchronized design was used. Sixty-four participants were recruited from out-patients setting in a university hospital by a convenient sampling. Two trained- hospice volunteers first provided regular hospice volunteer service to 34 patients in the control group. Subsequently, foot massage and supportive communication were provided to 30 participants in the experimental group. After the intervention, all participants answered the structured questionnaire with visual analog scales on depression, anxiety, and mood including general characteristics. Data were analyzed using descriptive statistics, two sample t-test, and paired t-test by PASW 17. Results: After the intervention, changes in negative moods, i.e. strain and powerlessness in the experimental group were significantly different from those in control group; strain and powerlessness in the experimental group were significantly decreased by foot massage and supportive communication provided by hospice volunteers. Conclusion: The current findings provide an empirical evidence of a brief and efficacious intervention for cancer patients. Further studies are warranted with larger sample size to validate the effectiveness of foot massage and supportive communication as a solid intervention for cancer patients who are undergoing intravenous chemotherapy at OPD.