• Title/Summary/Keyword: alternating method

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Childhood Fever Management: Current Practice vs Evidence (아동의 발열관리: 현황 및 과학적 근거)

  • Kim, Jin Sun
    • Child Health Nursing Research
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    • v.22 no.2
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    • pp.126-136
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    • 2016
  • Purpose: The purposes of this review were to address misconceptions of childhood fever and fever management practice among parents and health care providers, and to identify the scientific evidences against such misconceptions and practices. Methods: Journal databases and clinical guidelines from 2000 to 2015 were searched. The search terms were fever, fever management, misconception, myth, fiction, fact, fever phobia, child, antipyretics, tepid bath, alternating use/combined use of antipyretics, and physical cooling method. Results: There are significant gaps between current concepts and practices, and the scientific evidence. Misconceptions and unrealistic concerns about childhood fever still exist among parents and even health care providers, worldwide. The evidences suggest that antipyretics should be given carefully with the aim of relieving discomfort or pain rather than decreasing the temperature itself. Alternating use of antipyretics should be discouraged due to the risk of confusion and error. Antipyretics do not prevent febrile convulsions. Moreover, the scientific evidence does not support tepid sponge massage. Conclusion: Evidence-based childhood fever management interventions should be targeted toward parents and health care providers. By adopting an evidence-based approach to nursing interventions, pediatric nurses can ensure children receive appropriate and safe fever management.

Strength Evaluation for Crankshaft and its Oil Hole of Medium Speed Diesel Engine (중형 디젤 엔진 크랭크축 및 오일 홀에 대한 강도평가)

  • An, Sung-Chan;Son, Jong-Ho;Kim, Byung-Joo;Kim, Jong-Suk
    • Proceedings of the KSME Conference
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    • 2003.11a
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    • pp.1121-1126
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    • 2003
  • Strength evaluation was carried out for the fillet and oil hole of crankshaft of medium speed diesel HiMSEN engine to verify initial concept design. Alternating torque obtained from torsional vibration analysis and radial force due to firing pressure were applied. It was assumed that the maximum alternating torque and radial force occur simultaneously. Weak points in view of fatigue are proceeding fillet and crank pin fillet area and the minimum normalized fatigue safety factor is 1.17 at crank pin fillet. The fatigue strength of the oil hole was evaluated to verify the effect of the surface roughness of the oil hole. As results, the specific level of the inner surface roughness and the polishing depth of the oil hole for sufficient fatigue strength was suggested. The maximum stress value and stress distribution at the inner surface of the oil hole can be easily estimated at initial design stage by the newly developed method.

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Electrochemical, Antifungal, Antibacterial and DNA Cleavage Studies of Some Co(II), Ni(II), Cu(II) and Zn(II)-Copolymer Complexes

  • Dhanaraj, C. Justin;Nair, M. Sivasankaran
    • Mycobiology
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    • v.36 no.4
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    • pp.260-265
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    • 2008
  • Cyclic voltammetric measurements were performed for Co(II), Ni(II), Cu(II) and Zn(II) complexes of 1 : 1 alternating copolymer, poly(3-nitrobenzylidene-1-naphthylamine-co-succinic anhydride) (L) and Ni(II) and Cu(II) complexes of 1 : 1 alternating copolymer, poly(3-nitrobenzylidene-1-naphthylamine-co-methacrylic acid) ($L^1$). The in vitro biological screening effects of the investigated compounds were tested against the fungal species including Aspergillus niger, Rhizopus stolonifer, Aspergillus flavus, Rhizoctonia bataicola and Candida albicans and bacterial species including Staphylococcus aureus, Escherichia coli, Klebsiella pneumaniae, Proteus vulgaris and Pseudomonas aeruginosa by well diffusion method. A comparative study of inhibition values of the copolymers and their complexes indicates that the complexes exhibit higher antimicrobial activity. Copper ions are proven to be essential for the growth-inhibitor effect. The extent of inhibition appeared to be strongly dependent on the initial cell density and on the growth medium. The nuclease activity of the above metal complexes were assessed by gel electrophoresis assay and the results show that the copper complexes can cleave pUC18 DNA effectively in presence of hydrogen peroxide compared to other metal complexes. The degradation experiments using Rhodamine B dye indicate that the hydroxyl radical species are involved in the DNA cleavage reactions.

High Efficiency Alternating Current Driver for Capacitive Loads Using a Current-Balance Transformer

  • Baek, Jong-Bok;Cho, Bo-Hyung;Park, Joung-Hu
    • Journal of Power Electronics
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    • v.11 no.1
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    • pp.97-104
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    • 2011
  • This paper proposes a new alternating current driving method for highly capacitive loads such as plasma display panels or piezoelectric actuators, etc. In the proposed scheme, a current balance transformer, which has two windings with the same turn-ratio, provides not only a resonance inductance for energy recovery but also a current balance among all of the switching devices of the driver for current stress reduction. The smaller conduction loss than conventional circuits occurs due to the dual conduction paths which are parallel each other in the current balance transformer. Also, the leakage inductances of the transformer are utilized as resonant inductors for energy recovery by the series resonance to the capacitive load. Furthermore, the resonance contributes to the small switching losses of the switching devices by soft-switching operation. To confirm the validity of the proposed circuit, prototype hardware with a 12-inch mercury-free flat fluorescent lamp is implemented. The experimental results are compared with a conventional energy-recovery circuit from the perspective of luminance performances.

The Characteristics on the Change of Cerebral Cortex using Alternating Current Power Application for Transcranial Magnetic Stimulation

  • Kim, Whi-Young
    • Journal of Magnetics
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    • v.19 no.2
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    • pp.197-204
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    • 2014
  • A transcranial magnetic stimulation device is a complicated appliance that employs a switching power device designed for discharging and charging a capacitor to more than 1 kV. For a simple transcranial magnetic stimulation device, this study used commercial power and controlled the firing angle using a Triac power device. AC 220V 60 Hz, the power device was used directly on the tanscranial magnetic stimulation device. The power supply device does not require a current limiting resistance in the rectifying device, energy storage capacitor or discharge circuit. To control the output power of the tanscranial magnetic stimulation device, the pulse repetition rate was regulated at 60 Hz. The change trigger of the Triac gate could be varied from $45^{\circ}$ to $135^{\circ}$. The AVR 182 (Zero Cross Detector) Chip and AVR one chip microprocessor could control the gate signal of the Triac precisely. The stimulation frequency of 50 Hz could be implemented when the initial charging voltage Vi was 1,000 V. The amplitude, pulse duration, frequency stimulation, train duration and power consumption was 0.1-2.2T, $250{\sim}300{\mu}s$, 0.1-60 Hz, 1-100 Sec and < 1 kW, respectively. Based on the results of this study, TMS can be an effective method of treating dysfunction and improving function of brain cells in brain damage caused by ischemia.

Dynamically Alternating Power Saving Scheme for IEEE 802.16e Mobile Broadband Wireless Access Systems

  • Chang, Jau-Yang;Lin, Yu-Chen
    • Journal of Communications and Networks
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    • v.14 no.2
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    • pp.179-187
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    • 2012
  • Power saving is one of the most important features that extends the lifetime of portable devices in mobile wireless networks. The IEEE 802.16e mobile broadband wireless access system adopts a power saving mechanism with a binary truncated exponent algorithm for determining sleep intervals. When using this standard power saving scheme, there is often a delay before data packets are received at the mobile subscriber station (MSS). In order to extend the lifetime of a MSS, the battery energy must be used efficiently. This paper presents a dynamically alternating sleep interval scheduling algorithm as a solution to deal with the power consumption problem. We take into account different traffic classes and schedule a proper sequence of power saving classes. The window size of the sleep interval is calculated dynamically according to the packet arrival rate. We make a tradeoff between the power consumption and packet delay. The method achieves the goal of efficiently reducing the listening window size, which leads to increased power saving. The performance of our proposed scheme is compared to that of the standard power saving scheme. Simulation results demonstrate the superior performance of our power saving scheme and its ability to strike the appropriate performance balance between power saving and packet delay for a MSS in an IEEE 802.16e mobile broadband wireless access system.

Experimental and numerical analysis of fatigue behaviour for tubular K-joints

  • Shao, Yong-Bo;Cao, Zhen-Bin
    • Structural Engineering and Mechanics
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    • v.19 no.6
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    • pp.639-652
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    • 2005
  • In this paper, a full-scale K-joint specimen was tested to failure under cyclic combined axial and in-plane bending loads. In the fatigue test, the crack developments were monitored step by step using the alternating current potential drop (ACPD) technique. Using Paris' law, stress intensity factor, which is a fracture parameter to be frequently used by many designers to predict the integrity and residual life of tubular joints, can be obtained from experimental test results of the crack growth rate. Furthermore, a scheme of automatic mesh generation for a cracked K-joint is introduced, and numerical analysis of stress intensity factor for the K-joint specimen has then been carried out. In the finite element analysis, J-integral method is used to estimate the stress intensity factors along the crack front. The numerical stress intensity factor results have been validated through comparing them with the experimental results. The comparison shows that the proposed numerical model can produce reasonably accurate stress intensity factor values. The effects of different crack shapes on the stress intensity factors have also been investigated, and it has been found that semi-ellipse is suitable and accurate to be adopted in numerical analysis for the stress intensity factor. Therefore, the proposed model in this paper is reliable to be used for estimating the stress intensity factor values of cracked tubular K-joints for design purposes.

Electroluminescence Characteristics of OLED by Full-Wave Rectification Alternating Current Driving Method (전파 정류 교류 구동 방식에 의한 OLED의 전계발광 특성)

  • Seo, Jung-Hyun;Ju, Sung-Hoo
    • Korean Journal of Materials Research
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    • v.32 no.7
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    • pp.320-325
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    • 2022
  • Single OLED and tandem OLED was manufactured to analyze the electroluminescence characteristics of DC driving, AC driving, and full-wave rectification driving. The threshold voltage of OLED was the highest in DC driving, and the lowest in full-wave rectification driving due to an improvement of current injection characteristics. The luminance at a driving voltage lower than 10.5 V (8,534 cd/m2) of single OLED and 20 V (7,377 cd/m2) of a tandem OLED showed that the full-wave rectification drive is higher than that of DC drive. The luminous efficiency of OLED is higher in full-wave rectification driving than in DC driving at low voltage, but decrease at high voltage. The full-wave rectification power source may obtain higher current density, higher luminance, and higher current efficiency than the AC power source. In addition, it was confirmed that the characteristics of AC driving and full-wave rectification driving can be predicted from DC driving characteristics by comparing the measured values and calculated values of AC driving and full-wave rectification driving emission characteristics. From the above results, it can be seen that OLED lighting with improved electroluminescence characteristics compared to DC driving is possible using full-wave rectification driving and tandem OLED.

Estimation of structure system input force using the inverse fuzzy estimator

  • Lee, Ming-Hui
    • Structural Engineering and Mechanics
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    • v.37 no.4
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    • pp.351-365
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    • 2011
  • This study proposes an inverse estimation method for the input forces of a fixed beam structural system. The estimator includes the fuzzy Kalman Filter (FKF) technology and the fuzzy weighted recursive least square method (FWRLSM). In the estimation method, the effective estimator are accelerated and weighted by the fuzzy accelerating and weighting factors proposed based on the fuzzy logic inference system. By directly synthesizing the robust filter technology with the estimator, this study presents an efficient robust forgetting zone, which is capable of providing a reasonable trade-off between the tracking capability and the flexibility against noises. The period input of the fixed beam structure system can be effectively estimated by using this method to promote the reliability of the dynamic performance analysis. The simulation results are compared by alternating between the constant and adaptive and fuzzy weighting factors. The results demonstrate that the application of the presented method to the fixed beam structure system is successful.

A Study on the Loop Current Induced by Voltage Phase Difference Substations during Parallel Feeding under the Alternating Current AT Electric Power Feeding Method (교류 AT급전방식에서 병렬급전시 변전소간 전압위상차에 의한 루프전류에 관한 연구)

  • Park, Jae-Seok;Song, Joong-Ho
    • Proceedings of the KSR Conference
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    • 2011.10a
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    • pp.1997-2004
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    • 2011
  • The $2{\times}25kv$ AT electric power feeding method in the A.C. electric train adopts the one-phase power feeding method as the standard due to a voltage phase difference, and the distance between the two neighboring substations is 50km due to voltage drop. The one-phase power feeding method makes the system operation feasible, while making it unfavorable for power supply. Moreover, railroad involves large-capacity single-phase load, and if it is expected to continue to rise, it is necessary to research on measures to stabilize the supply of power to railroad cars with the existing facilities. In this study, a parallel power feeding method between neighboring substations is proposed to stabilize the supply of electric power to electric railroad cars under the 2*25kv AT power feeding method and the loop current induced by voltage phase difference between the two neighboring substations during parallel power feeding is investigated.

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