• Title/Summary/Keyword: Square pulse

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Effects of Nurse Presence Program on Anxiety and Physiological Indicators in Patients with Gynecological Surgery (Nurse Presence 프로그램이 산부인과 수술환자의 불안 및 생리적 지수에 미치는 효과)

  • Kim, Yun Jeong;Jo, Kae Hwa
    • Journal of Korean Biological Nursing Science
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    • v.16 no.4
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    • pp.326-333
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    • 2014
  • Purpose: This study was to examine the effects of Nurse Presence (NP) program on anxiety and physiological indicators in patients with gynecological surgery. Methods: This study used a randomized control group pre-test, post-test design. The patients were 25-65 years old who had undergone gynecological surgery with general anesthesia. The subjects were divided into an experimental group (n=30) and the control group (n=30). SPSS 21.0 was used to analyze the data with Chi-square, Fisher's exact test, t-test, and one sample t-test. Results: The results show that there were significant differences in anxiety and heart rate and were no significant differences in systolic pressure or peripheral oxygen saturation of the experimental group which received the NP program. Conclusion: Nurse Presence program decreased pulse rate which is a physiological indicator by relieving the anxiety of the patients before gynecological surgery. Thus, this intervention is effective to relieve anxiety of the patients before gynecological surgery and should be utilized in clinics.

Development of Electrical Stimulator for Auditory Stimulation (청각 자극용 전기자극기 개발)

  • Heo, Seung-Deok;Jung, Dong-Keun;Kim, Lee-Suk;Kim, Gwang-Nyeon;Kang, Myung-Koo;Kim, Jae-Ryong;Kim, Gi-Ryon
    • Speech Sciences
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    • v.11 no.3
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    • pp.201-211
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    • 2004
  • This paper introduces a development of an electrical stimulator for auditory stimulation. The electrical stimulator is useful in neurotological diagnosis, audiological evaluation, candidate selection for cochlear implantation, optimal device selection and decision making of MAP strategy for severe-to-profound hearing impaired persons. The development was based on sound parameters of auditory brainstem responses and auditory electrophysiological characteristic such as effective firing of auditory nerve and recording evoked potentials during refractory period of neuron. Besides pulse parameter could adjustable by programming for more varied electrical stimulation evoked response audiometry. Using the electrical stimulator, electrical square pulse was applied to promontory, and electrically evoked auditory brainstem response and electrically middle latency response were successfully recorded in cats.

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Cavity and Interface effect of PI-Film on Charge Accumulation and PD Activity under Bipolar Pulse Voltage

  • Akram, Shakeel;Wu, Guangning;Gao, GuoQiang;Liu, Yang
    • Journal of Electrical Engineering and Technology
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    • v.10 no.5
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    • pp.2089-2098
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    • 2015
  • With the continuous development in insulation of electrical equipment design, the reliability of the system has been enhanced. However, in the manufacturing process and during operation under continues stresses introduce local defects, such as voids between interfaces that can responsible to occurrence of partial discharge (PD), electric field distortion and accumulation of charges. These defects may lead to localize corrosion and material degradation of insulation system, and a serious threat to the equipment. A model of three layers of PI film with air gap is presented to understand the influence of interface and voids on exploitation conditions such as strong electrical field, PD activity and charge movement. The analytical analysis, and experimental results are good agreement and show that the lose contact between interfaces accumulate more residual charges and in consequences increase the electric field intensity and accelerates internal discharges. These residual charges are trapped charges, injected by the electrodes has often same polarity, so the electric field in cavities increases significantly and thus partial discharge inception voltage (PDIV) decreases. Contrary, number of PD discharge quantity increases due to interface. Interfacial polarization effect has opposite impact on electric field and PDIV as compare to void.

Carrier Phase-Shift PWM to Reduce Common-Mode Voltage for Three-Level T-Type NPC Inverters

  • Nguyen, Tuyen D.;Phan, Dzung Quoc;Dao, Dat Ngoc;Lee, Hong-Hee
    • Journal of Power Electronics
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    • v.14 no.6
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    • pp.1197-1207
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    • 2014
  • Common-mode voltage (CMV) causes overvoltage stress to winding insulation and damages AC motors. CMV with high dv/dt causes leakage currents, which create noise problems for equipment installed near the converter. This study proposes a new pulse-width modulation (PWM) strategy for three-level T-type NPC inverters. This strategy substantially eliminates CMV. The principle for selecting suitable triangle carrier signals for the three-level T-type NPC is described. The proposed method can mitigate the peak value of CMV by 50% compared with the phase disposition pulse-width modulation method. Furthermore, the proposed method exhibits better harmonic spectrum and lower root mean square value for the CMV than those of the reduced-CMV method on the basis of the phase opposition disposition PWM scheme with modulation index higher than 0.5. The proposed modulation can easily be implemented using software without any additional hardware modifications. Both simulation and experimental results demonstrate that the proposed carrier phase-shift PWM method has good output waveform performance and reduces CMV.

Back Massage to Decrease State Anxiety, Cortisol Level, Blood Prsessure, Heart Rate and Increase Sleep Quality in Family Caregivers of Patients with Cancer: A Randomised Controlled Trial

  • Pinar, Rukiye;Afsar, Fisun
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.18
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    • pp.8127-8133
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    • 2016
  • Background: The objective of this study was to evaluate the effect of back massage on the anxiety state, cortisol level, systolic/diastolic blood pressure, pulse rate, and sleep quality in family caregivers of patients with cancer. Materials and Methods: Forty-four family caregivers were randomly assigned to either the experimental or control group (22 interventions, 22 controls) after they were matched on age and gender. The intervention consisted of back massage for 15 minutes per day for a week. Main research outcomes were measured at baseline (day I) and follow-up (day 7). Unpaired t-test, paired t test and chi-square test were used to analyse data. Results: The majority of the caregivers were women, married, secondary school educated and housewife. State anxiety (p<0.001), cortisol level (p<0.05), systolic/diastolic blood pressure (p<0.001, p<0.01 respectively), and pulse rate (p<0.01) were significantly decreased, and sleep quality (p<0.001) increased after back massage intervention. Conclusions: The study results show that family caregivers for patients with cancer can benefit from back massage to improve state anxiety, cortisol level, blood pressure and heart rate, and sleep quality. Oncology nurses can take advantage of back massage, which is non-pharmacologic and easily implemented method, as an independent nursing action to support caregivers for patients with cancer.

The Effects of Aroma Foot Massage on the Anxiety, Pain and Sleep Satisfaction during Colonoscopy under Conscious Sedation (아로마 발마사지가 수면대장내시경 대상자의 불안과 통증 및 수면만족도에 미치는 효과)

  • Sung, Ki-Wol;Kim, Myung-Hee
    • Research in Community and Public Health Nursing
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    • v.17 no.1
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    • pp.91-101
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    • 2006
  • Purpose: This research is to know whether aroma foot massage has influence on the relief of anxiety and pain during colonoscopy under conscious sedation. Method: This research was designed as a quasi-experiment of non-equivalent control group pretest-posttest. Data were collected from April 1 2005 to August 30 2005. The subjects were divided into three groups (control group, foot massage group and aroma foot massage group) with 30 persons each. Anxiety was evaluated with Visual Analogue Scale (VAS), blood pressure and pulse. Pain response was measured with VAS and non-verbal pain behavior score. Sleep satisfaction was measured with a graphic rating scale. Data were analyzed through Chi-square test, t-test and repeated measure ANOVA. Results: Systolic blood pressure, pulse, subjective anxiety and pain scores from the aroma foot massage group decreased significantly. Sleep satisfaction score of the aroma foot massage group increased significantly. Diastolic blood pressure from the aroma foot massage group did not decrease. Conclusion: The results show that aroma foot massage with refined oils can increase sleep satisfaction and decrease anxiety and pain during colonoscopy under conscious sedation.

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Experimental Study of Second Harmonic Ultrasound imaging with a Weighted Chirp Signal (가중 쳐프 신호를 사용한 초음파 고조파 영상 기법의 실험적 고찰)

  • 김동열;이종철;송태경
    • Proceedings of the IEEK Conference
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    • 2001.06d
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    • pp.151-154
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    • 2001
  • In this Paper, a new harmonic imaging technique is proposed and evaluated experimentally. In the proposed method, a weighted chin signal with a hanning window is transmitted. The RF samples obtained on each array element are individually compressed by correlating with the reference signal defined as the 2nd harmonic (2f0) component of a transmitted chirp signal generated in a square-law system. The proposed method uses the compressed 2f0 component to form an image, for which the crosscorrelation term with f0 component should be suppressed below at least -60dB. After experiment, the 6dB pulse width and peak sidelobe level of the compressed 2f0 component were 0.7us and -60dB, respectively. This result shows that the proposed method can successfully eliminate the f0 component with a single transmit-receive event and therefore is more efficient than the conventional pulse inversion (PI) method in terms of frame rate. We also observed that the 2nd harmonic compont starts to decrease for source pressure higher than 210kPa in water, which implies that SNR of the 2nd harmonic imaging using short pulses cnanot be incresed beyond a certain limit.

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Residual Vibration Suppression of a Beam-Mass-Cart System by Input Reshaping with a Robust Inernal-loop Compensator (강인한 내부 루프 보상기를 입력성형법에 의한 유연보-부하-대차 시스템의 잔류진동 억제)

  • Park, Sangdeok;Kim, Bong-Keun;Chung, Wan-Kyun;Yeom, Yeong-Il
    • Journal of Institute of Control, Robotics and Systems
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    • v.7 no.3
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    • pp.198-208
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    • 2001
  • In this paper, vibration suppression of an elastic beam fixed on a moving cart and carrying a fixed or moving mass is considered. A modified pulse sequence method with RIC(Robust Internal-loop Compensator) is proposed to suppress the single model residual vibration and to get accurate positioning of the beam-mass-cart system. The performance of the proposed input preshaping method is compared with that of the previous ones through simulations and experiments. Using the proposed method, it is able to suppress the initial vibration of the beam-mass-cart system carrying a concentrated mass. Accurate PTP(point-to-point) positioning of the moving mass without residual vibration is also obtained experimentally by modifying the proposed pulse sequence method. Finally, the proposed input preshaping method is applied successfully to the system to follow square trajectories of the moving mass without residual vibration.

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New Reset Waveform for a Large-Sustain-Gap Structure in AC PDPs (AC PDP의 장방전 구조의 구동을 위한 새로운 리셋파형)

  • Kim, Sun;Kim, Dong-Hun;Song, Tae-Yong;Kim, Ji-Yong;Lee, Seok-Hyun;Seo, Jeong-Hyun
    • Proceedings of the KIEE Conference
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    • 2006.07c
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    • pp.1544-1545
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    • 2006
  • In this paper, we present a new reset waveform for a large-sustain-gap structure in at PDPs. In the driving of the large-sustain-gap structure with a conventional ramp reset waveform, we cannot avoid the condition of an address being a cathode, which causes lots of trouble in stabilizing a reset discharge. To solve these problems, we use the square pulse instead of the conventional rising ramp pulse. Before making a strong discharge between the address (cathode) and scan (anode) electrodes, we make a priming discharge between the address (anode) and the scan (cathode) electrodes to stabilize the strong discharge in which the address electrodes are the cathode. With this scheme, we obtained 60V minimum address voltage and 145V maximum address voltage in $250{\mu}m$ and $350{\mu}m$ gap structures.

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전자기 성형에서의 테이퍼진 지속집중기의 자기압력에 관한 연구

  • Choe, Jae-Chan;Jo, Yong-Cheol;Lee, Jong-Su;Hwang, Un-Seok;Kim, Nam-Hwan
    • Journal of the Korean Society for Precision Engineering
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    • v.7 no.2
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    • pp.14-27
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    • 1990
  • Electromagnetic Pulse Forming is the one of the high velocity forming method. When the electric energy which is charged in the capacitor bank is suddenly discharged into the electromagnetic coil, the high magnetic field occurs at the airgap between the electromagnetic coil and workpiece. Thus we can obtain the high electromagnetic pressure, which is proportional to the square of magnetic flux density. This is the basic principle of the electromagnetic pulse forming. In this paper, the equivalent L-R-C circuit is derived by computing the magnetic field and its loss of the total system. Thus, the values of the magnetic flux density and pressure can be obtained from the equation of this circuit. As a result, the computed and measured values of the maximum magnetic flux density and pressure are compared and the characteristics of the tapered field shaper are further discussed as follows; 1) The strength of magnetic flux density and pressure can be controlled by the charged energy and the size of the airgap between the inner field shaper and the workpiece. 2) During the design of the tapered field shaper, the penetration of the magnetic flux through the sharp edge should be considered.

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