• 전기의세계
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• v.28 no.3
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• pp.72-77
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• 1979

The object of this paper is to try to develope Tulular Liner Induction Motor which consists of primary stator that generates traveling magnetic field from the three-phase winding of formed-wound concentric coil, and try to identify the characteristics of starting force. To indentify the theoretical starting force formular we have quoted the conventional Maxwell's basic equation and Poisson's equation which are used in the general machines thereby having obtained the formular of the current with in the conductor and of the air gap magnetic field respectively. General starting force formular is acquired by applying the formular of the current and magnetic field which was theoretically derived above. To this theoretically starting force formula various constants and the values of magnetic flux density resulting from the experimental motor are applied to present theoretically calculated values. Comparing these theoretically caculated values experimentally weighed values, we have proved the validity of theoretical research.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.8 s.173
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• pp.136-142
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• 2005

The function of main starting valve for marine engine is to supply cylinder with the air to start marine engine. But, if the spindle, one of the main starting valve components, doesn't rotate accurately at the designated air pressure, the marine engine may have some trouble in starting. So, to resolve the problem due to spindle .elation in the main starting valve, the blocking device (blocking plate, limit switch, etc.) is installed in the upper part of spindle to constrain the rotation. So, in this paper we introduced the rotation constraining ability of blocking plate prevent the spindle from mis-working in the main starting value of the marine engine.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.8 s.239
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• pp.934-939
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• 2005

Starting pressure of a supersonic ejector with a second-throat was investigated. In case of mixing chamber length longer than a critical length, starting pressure is in proportion to length of the mixing chamber. In this study, we assumed that the ejector starts when the primary supersonic flow reaches inlet of the second-throat and the distance of the supersonic flow traveling can be expressed by multiplying an empirical factor to the first diamond shock length of overexpanded flow. To calculate the overexpanded supersonic flow, a mixing model was employed to compute secondary flow pressure and the result was applied to back pressure condition of overexpanded flow calculation. In the result, for three cases of primary nozzle area ratio, we could get accurate model of predicting the starting pressure by selecting a suitable empirical factors around 3.

• Journal of Power System Engineering
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• v.14 no.2
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• pp.12-15
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• 2010

It is requested to shorten the starting duration for idle stop function equipped cars without harmful effects on the environment. Higher cranking speeds can be achieved with high torque starter. The object of this study is to develope the high torque starter and evaluate its effect on the exhaust emissions. The test was conducted on a 1.5 L, 4-cylinder, 16 valve, multipoint-port-fuel-injection gasoline engine. Engine out emissions such as HC, CO, $CO_2$, and the excess air ratios, lambda were measured using MEXA-554JK. The result showed that a high torque starter, HTS-II shortened the starting duration and reduced engine out emissions of HC, CO and improved starting performance with larger excess air ratio than that of the original starter, Org. S and a high torque starter, HTS-I.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.6
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• pp.215-221
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• 1997

The ability of the engine starting performance of conventional ignition system being currently used in automobile gasoline engine is investigated, and the method of improving is discussed and experimented. The conventional ignition system cannot obtain high ignited voltage because its current is limited by decreasing of terminal voltage of battery at starting the engine also causes irregularity in the starting engine. This paper shows that problem can be improved practically by control of ignition energy properly according to the engine speed, consequently this experimental ignition system can eliminate to remarkable extent the function of the engine starting, and also enhance the performance of the engine at high speed.

• Journal of Navigation and Port Research
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• v.33 no.2
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• pp.127-134
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• 2009

If the research on double cycle is revitalized, crane productivity will be rapidly improved bemuse double cycle is an operational technique that can maximize equipments efficiency (Quay crane, RMG/RTG, Yard tractor). Unfortunately, it is very difficult for terminal operators to find out the starting point of double cycle bemuse the loading & unloading pattern and conditions are various. Therefore, terminal operators are apt to fail to find out the optimal starting point of double cycle to maximize its frequency. Experiencing the same mistakes in the process we made efforts to find out the optimal starting point, finally we found out the formula for it. And we verified its precision is perfect through a lot of testing. This paper on double cycling focused on making the formula to find out optimal starting point of double cycle to maximize its frequency. And it can be applied to various ships' stowages in common.

• Journal of the Korean Ceramic Society
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• v.53 no.5
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• pp.541-547
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• 2016

In developing high temperature molds with advantages of the sand and precision (investment) castings, mechanical properties of the mold were improved through homogeneous coating of starting powders with an inorganic binder and improvement of fabrication process. Beads with mullite composition were employed for properties of the mold under high temperature, which was compared with artificial sands. Precursors of silica and sodium oxide were used as starting materials for an inorganic binder to achieve homogeneous coating on the starting powders. Strength was enhanced by the glass phase converted from the inorganic binder through heat treatment process. Also, two kinds of process, wet and dry processes, were incorporated to prepare mold specimens. Consequently, fabrication process of the mold with superior strength and high temperature applicability, compared with the previous molds for sand casting, could be suggested through control of the starting material and enhancement of the vitrification efficiency.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.1030-1032
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• 2003

Single phase SRM(switched reluctance motor) can not be start by itself because positive torque is generated in limited section. Therefore single phase SRM need starting device which is place the rotor in positive torque section when motor is begun to start. The prototype of salient pole rotor type single phase SRM, fabricated in previous research, has permanent magnet starting device. It is installed in bottom of the rotor for starting by itself. But, it is affected the motor when driving and cause the decrease of torque and speed. On this paper, average torque of the prototype was measured according to installation of the starting device or not. And influence of the staring device on average torque was confirmed by comparison of the results.

• Proceedings of the KIEE Conference
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• 2003.11a
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• pp.91-94
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• 2003

A DC railway system has low feeder voltage, The fault current can be smaller than the current of load starting. So it is important to discriminate between the small fault current and the load starting current. The load starting current increases step by step but the fault current increases all at once. So the type of ${\Delta}I$ relay(50F) was developed using the different characteristics between the load starting current and the fault current. As for the load starting current, the time constant of load current at each step is much smaller than that of the fault current. First, to detect faults in DC railway systems, an algorithm using the time constant calculated by the method of least squares is presented in this paper. Secondly, to compose a protection scheme for DC railway systems is presented in this paper.

• Proceedings of the KIEE Conference
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• 2006.07e
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• pp.61-62
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• 2006

Since the starting reactor used for reducing inrush current of high voltage induction motor applies an electric current only when it is at the stage of transition, it gets lots of electrical or mechanical stress. In this aspect, the reliability on the starting reactor is very important because the reactor-relating-accident takes 80% of all the accident concerned with high voltage motor starting panel. In this study, we conducted an insulation test of starting reactor of high voltage induction motor of intake pumping station to the Seoul area And the result from this study was used as data for determining whether it's still usable or not.