• Proceedings of the KIPE Conference
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• 2011.07a
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• pp.296-297
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• 2011

Many applications involving induction motors that are controlled using variable frequency drives require the ability to stop quickly. These applications include emergency stops, quick stopping of fans, centrifuges, presses, etc. The technique that is widely accepted in the industry for achieving quick stopping makes use of brake resistors in series with a power semiconductor switch. The switch-resistor combination (brake-unit) is applied across the dc bus. The fastest decelerating time achievable depends on the size of the resistors and the switch employed. In this paper, the authors propose a novel method of achieving quick stopping times without the use of any brake-unit. Experimental test results with and without this method on a large inertia motor-load combination show that the proposed stopping method is able to reduce the stopping time significantly compared to normal decelerated stop without the need for a braking unit.

• Journal of Advanced Information Technology and Convergence
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• v.8 no.2
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• pp.119-127
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• 2018

Training a very large deep neural network can be painfully slow and prone to overfitting. Many researches have done for overcoming the problem. In this paper, a combination of early stopping and ADAM based deep neural network was presented. This form of deep network is useful for handling the big data because it automatically stop the training before overfitting occurs. Also generalization ability is better than pure deep neural network model.

• Journal of Ocean Engineering and Technology
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• v.34 no.1
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• pp.13-18
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• 2020

An azimuth propeller can generate thrust in all directions by rotating its housing with an electric motor. An azimuth propeller can be operated using several methods to stop a ship. This study aims to derive an efficient method to stop a ship safely using an azimuth propeller through full-scale maneuvering trials with the research vessel "NARA" of Pukyong National University in 4.63 m/s (9 kts). Five methods with different azimuth propeller operations were tested to stop the ship. The test results confirmed that the simultaneous use of the thrust and the hydrodynamic force acting on the strut is the most effective method to stop the ship.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.7 no.4
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• pp.187-194
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• 1974

When rearing fish at recirculating filter systems, some pesticides are often used for controling various fish diseases. In this case, the pesticides are usually applied after stopping the filteration, from a view point of affecting the filtering ability of oxidation and decomposition by killing the decomposing bacteria in the filter system. Therefore, a great inconvenience is usually net. The authors carried out a series of experiments, and the influence of 3 kinds of treatments of pesticides, formalin 33 ppm+matachite green 0.15 ppm, dipterex 0.25 ppm, and furanace 0.1 ppm, to the filtering ability expressed as the consumption rate of dissolved oxygen and depletion of ammonia-nitrogen during the passing time through the filter layer was investigated, and it was found out that these pesticides with above mentioned concentrations which is normally used for controling several kinds of diseases and parasites during the time of eel culture, did not affect the filtering ability. Consequently, it can be said that these pesticides with above mentioned concentrations can he used without stopping filteration.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.98-114
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• 2002

The completion of the draft sequence of the human genome has provided us with a partial list of known and putative human genes, the total number of which is estimated between 30, 000 and 45, 000 (1, 2). These genes provide many potential targets for drugs, some of which may be useful in stopping the growth of cancers. The development of gene-targeting anticancer drugs could be greatly facilitated by the ability to narrow down the list of human genes to those that are necessary for the growth of tumor cells. (omitted)

• The KIPS Transactions:PartD
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• v.8D no.2
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• pp.175-180
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• 2001

This paper presents the optimal fraction of validation set to obtain a prediction accuracy of software failure count or failure time in the future by a neuro-fuzzy system. Given a fixed amount of training data, the most popular effective approach to avoiding underfitting and overfitting is early stopping, and hence getting optimal generalization. But there is unresolved practical issues : How many data do you assign to the training and validation set\ulcorner Rules of thumb abound, the solution is acquired by trial-and-error and we spend long time in this method. For the sake of optimal fraction of validation set, the variant specific fraction for the validation set be provided. It shows that minimal fraction of the validation data set is sufficient to achieve good next-step prediction. This result can be considered as a practical guideline in a prediction of software reliability by neuro-fuzzy system.

• Journal of the Korean Society of Safety
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• v.23 no.3
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• pp.71-78
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• 2008

This study aims to identity the age group where driving performance significantly decreases based on the data collected from the Korea Transportation Safety Authority's driver aptitude tests in 2006. The test includes following six driving simulator-based tests: estimation of moving objects' speed, estimation of stopping distance, three tests for drivers' multi-task ability, and kinetic depth perception. These six test results were utilized for the identification of the age threshold applying the CART technique, suggesting driving ability significantly be decreased over 50s. This finding was confirmed by two analyses using the accident history data containing the information of accident and non-accident drivers and the degree of accident severity. The results of this study imply that accident prevention efforts should be enhanced over a wider range of age group than the current practice where the age of 65 is generally applied for the threshold dividing senior and non-senior driver groups.

• Journal of the Korean Society of Marine Environment & Safety
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• v.8 no.2
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• pp.9-15
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• 2002

Ship operators use anchor dredging for the collision avoidance or safety of ship handling in a harbour or narrow channel. This paper clarifies the technique of the anchor dredging known as a common sense for. the seafarers A mathematical model at low speed range is established for the estimation of ship motion under the assumed environment, simulate the advance speed , and turning ability under the anchor dredging or not. The results shows good agreement with the conventional seamanship and their experiences as follows. Ahead speed used the anchor dredging is slower(speed reduction ratio:40%) than the normal ahead speed and the stopping distance is shorter (distance reduction ratio:40%)than the normal ahead distance without the anchor dredging.. Turning speed used anchor dredging is slower(speed reduction ratio:72%)than the normal ahead speed and the tactical diameter is shorter(distance reduction ratio:24%)than the diameter by the normal turning without the anchor dredging.

• The Korean Journal of Pain
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• v.24 no.2
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• pp.112-114
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• 2011

Due to its complex pathophysiology and wide spectrum of clinical manifestations, the diagnosis of CRPS is often missed in the early stage by primary care physicians. After being treated by a primary care physician for 5 months for chronic cellulitis, a 16-year-old girl was referred to our hospital with features of type-1 CRPS of the right upper extremity. Inability to diagnose early caused prolonged suffering to the girl with all the consequence of CRPS. The patient responded well with marked functional recovery from multimodal therapy. Ability to distinguish CRPS from other pain conditions, referral for specialty care at the appropriate time and full awareness of this condition and its clinical features among various healthcare professionals are essential in reducing patient suffering and stopping its progression towards difficult-to-treat situations.

• Proceedings of KOSOMES biannual meeting
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• 2002.10a
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• pp.127-134
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• 2002

Ship operators are used to dredge anchor for the collision avoidance or safety of ship handling in a harbour or narrow channel. This paper clarifies the technique using tile anchor dredging known as a common sense for the seafarers. A mathematical model at low speed range has been established for the estimation of ship motion under the assumed environment , simulate the advance speed , and turning ability under the anchor dredging or not. The results shows good agreement with the conventional seamanship and their experiences as follows. Ahead speed used the anchor dredging is slower(speed reduction ratio:40%) than the normal ahead speed and the stopping distance is shorter (distance reduction ratio:40%)than the normal ahead distance without the anchor dredging. Turning speed used anchor dredging is slower(speed reduction ratio:72%)than the normal ahead speed and the tactical diameter is shorter(distance reduction ratio:24%)than the diameter by the normal turning without the anchor dredging.