• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.11B no.4
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• pp.175-179
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• 2001

The switched reluctance drive exhibits higher levels of vibration and acoustic noise than that of most competing drives. The main source of vibration in the switched reluctance drive is generated by rapid change of radial force when phase current is extinguished by commutation action. A new excitation strategy for a Switched Reluctance Motor with Auxiliary Winding (SRMAW) is described and tested. This scheme has auxiliary winding with one diode which is sound to all th poles in one winding. In this scheme, auxiliary winding is used to reduce magnetic stress during commutations. The abrupt change of a phase excitation produces mechanical stresses and it results in vibration and noise. The acoustic noise is reduced remarkably through 2-stage commutation. The operational principle and a characteristic comparison to that of the conventional SRM show that this scheme has some advantages including noise reduction as well as high efficiency drive.

• English Language & Literature Teaching
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• v.12 no.3
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• pp.99-122
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• 2006

The purpose of this paper is to explain the meanings and uses of the English auxiliaries SHALL/WILL. The complexity of modern usage of SHALL/WILL has been one of the most disputable themes of traditional English grammar. The paper purported to address the study and analysis of diachronic and synchronic approach to the two auxiliaries. A general view of the figures of Fries'(1925) survey was added for further investigation. The results of the study showed that these auxiliaries express some of various modal meanings associated with the volitional or emotional attitude of the speaker without implying futurity. The findings also suggested that the use of SHALL in present-day English is restricted to non-volitional future with the first person but the practice of this use is also diminished by the expansion of the use of WILL, and the original meaning of WILL, 'to desire or wish', has generally been replaced by other verbs or modal forms. But sentences which seem to indicate futurity are often tinged with modal senses. Therefore, WILL/SHALL should be considered to act either as tense auxiliary or as modal auxiliary depending on situational contexts in which it occurs.

• The Transactions of the Korean Institute of Power Electronics
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• v.24 no.6
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• pp.389-395
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• 2019

This paper presents the sensorless position control of an auxiliary scaffolding step system for vehicles using DC motors. The designed auxiliary scaffolding step has a mechanical protector at the stop position. At this position, the scaffolding is forcibly stopped by the mechanical protector, and the motor current is dramatically increased to the stall current of the DC motor, thereby increasing the electrical damage. In this study, the estimated back EMF- and current model-based observers are proposed to estimate the motor speed and stop position. A simple V/F acceleration voltage pattern is used to operate the auxiliary scaffolding system. The estimated moving position is adopted to determine the stop position of the DC motor with the load current state. The operating current of the DC motor can be reduced by the estimated moving position and V/F acceleration pattern. At the stop position, the proposed sensorless position controller can smoothly stop the DC motor with the estimated moving position and reduced load current without any mechanical and electrical stress from the stall current from the mechanical protector. The proposed control scheme is verified by the comparison of simulations and experiments.

• Journal of the Korean Society of Safety
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• v.30 no.4
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• pp.46-50
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• 2015

This paper describes the measurement and analysis of ground impedance according to arrangement of auxiliary probe around ground grid using the fall-of-potential method and the testing techniques to minimize the measuring errors are proposed. The fall-of-potential method involves passing a current between a ground electrode and a current probe, and then measuring the voltage between a ground electrode and a potential probe. To minimize interelectrode influences due to mutual resistances, the current probe is a generally placed at a substantial distance from the ground electrode under test. In order to analyze the effects of ground impedance due to the arrangement of auxiliary probe and frequency, ground impedances were measured in case that the arrangements of auxiliary probe were straight line, perpendicular line, and horizontal line. The distance of current probe was located from 10[m] to 200[m] and the measuring frequency was ranged from 55[Hz] to 513[Hz]. As a consequence, the ground impedance increases with increasing the distance from the ground electrode to the point to be tested, but the ground impedance decreases with increasing the frequency.

• Journal of Power Electronics
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• v.4 no.3
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• pp.161-168
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• 2004

This paper presents a new circuit topology of high-frequency soft switching commutation boost type PWM chopper-fed DC-DC power converter with a loadside auxiliary passive resonant snubber. In the proposed boost type chopper-fed DC-DC power converter circuit operating under a principle of ZCS turn-on and ZVS turn-off commutation, the capacitor and inductor in the auxiliary passive resonant circuit works as the lossless resonant snubber. In addition to this, the voltage and current peak stresses of the power semiconductor devices as well as their di/dt or dv/dt dynamic stress can be effectively reduced by the single passive resonant snubber treated here. Moreover, it is proved that chopper-fed DC-DC power converter circuit topology with an auxiliary passive resonant snubber could solve some problems on the conventional boost type hard switching PWM chopper-fed DC-DC power converter. The simulation results of this converter are illustrated and discussed as compared with the experimental ones. The feasible effectiveness of this soft witching DC-DC power converter with a single passive resonant snubber is verified by the 5kW, 20kHz experimental breadboard set up to be built and tested for new energy utilization such as solar photovoltaic generators and fuel sell generators.

• Structural Engineering and Mechanics
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• v.25 no.3
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• pp.347-363
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• 2007

A novel methodology, referred to as Auxiliary Domain Method (ADM), allowing for a very efficient solution of nonlinear reliability problems is presented. The target nonlinear failure domain is first populated by samples generated with the help of a Markov Chain. Based on these samples an auxiliary failure domain (AFD), corresponding to an auxiliary reliability problem, is introduced. The criteria for selecting the AFD are discussed. The emphasis in this paper is on the selection of the auxiliary linear failure domain in the case where the original nonlinear reliability problem involves multiple objectives rather than a single objective. Each reliability objective is assumed to correspond to a particular response quantity not exceeding a corresponding threshold. Once the AFD has been specified the method proceeds with a modified subset simulation procedure where the first step involves the direct simulation of samples in the AFD, rather than standard Monte Carlo simulation as required in standard subset simulation. While the method is applicable to general nonlinear reliability problems herein the focus is on the calculation of the probability of failure of nonlinear dynamical systems subjected to Gaussian random excitations. The method is demonstrated through such a numerical example involving two reliability objectives and a very large number of random variables. It is found that ADM is very efficient and offers drastic improvements over standard subset simulation, especially when one deals with low probability failure events.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.1
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• pp.94-98
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• 2010

The auxiliary power supply for satellite should make the power safe and support it for subsystems during its operational lifetime. Several contstraints should be required to get high reliability. In this paper, the auxiliary power supply was satisifed and designed to be satisified with some contstraints. Control circuits for the auxiliary power supply used majority voter circuits to remove the single point failure. To verify majority voter circuits, proto-type auxiliary power supply was manufactured and tested.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.15 no.1
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• pp.107-113
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• 2008

Purpose: The purpose of this study was to identify the degree and relationship between self-esteem, depression, and suicidal ideation of youths in the auxiliary police force. Method: This descriptive study was conducted using a structured questionnaire from February 1 to March 25, 2007. The participants were 180 youths from 19 to 25 years old (average 20.82 years old) who were auxiliary policemen. The data were analyzed using the SPSS Win 12.0 program. Results: Six of the auxiliary police (3.34%) reported critical scores in suicidal ideation. There was a significant difference in depression according to work area. Self-esteem showed a significant negative correlation with depression (r=-0.38, p<.001) and suicidal ideation (r=-0.39, p<.001). There was a positive correlation between depression and suicidal ideation(r=0.53, p<.001). Conclusion: The findings suggest that auxiliary policemen have higher levels of depression and suicidal ideation. Therefore, further study is needed to develop and examine nursing interventions the enhance self-esteem, so that depression and suicidal ideation can be minimized.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.1
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• pp.188-195
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• 2015

This paper presents measurement error reduction technique of touch and step voltage of grounding system based on numerical analysis. When measuring touch and step voltage of grounding system, auxiliary current probes should be located at suitable places. However, the auxiliary probes can not be located at suitable places in such cases as there are buildings and pavements. Therefore, in this paper, we provided measurement error reduction technique of touch and step voltage of grounding system according to the positions of auxiliary probes and angle between auxiliary probes. Also, measurement error analyses of touch and step voltage of grounding system have been conducted using more than one current probe. Based on these analyses, recommended positions of auxiliary probes within allowable measurement errors were presented.

• Transactions of the Korean Society of Automotive Engineers
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• v.23 no.2
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• pp.230-238
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• 2015

The main purpose of this paper is to suggest opportunities for reducing $CO_2$ emission in energy conversion of a vehicle, focused on auxiliary energy improvement in the automotive field. As part of worldwide efforts to curb global warming and to protect the domestic industry as trade barriers, many countries have set goals to regulate greenhouse gas emissions. As an example, new $CO_2$ emission regulation in EU was expected to go into effect strictly in 2020. Therefore, global car-makers need to establish strategic responsiveness of the regulations. This paper shows $CO_2$ economic value by using the correct interpretation of the relevant laws and regulations. The $CO_2$ value analyzed using quantitative figures leads to the possibility of auxiliary(accessories, HVAC, electric apparatus etc.) technology for improving fuel economy. As a result, this study generalizes the meaning of electric power saving for each driving mode by auxiliary energy improvement.