• Journal of Elementary Mathematics Education in Korea
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• v.14 no.1
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• pp.65-80
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• 2010

The aims of our study are to investigate the nature of mathematical reasoning and the teaching of mathematical reasoning in school mathematics. We analysed the process of shaping deduction in ancient Greek based on Netz's study, and discussed on the comparison between his study and Freudenthal's local organization. The result of our analysis shows that mathematical reasoning in elementary school has to be based on children's natural language and their intuitions, and then the mathematical necessity has to be formed. And we discussed on the sequences and implications of teaching of the sum of interior angles of polygon composed the discovery by induction, justification by intuition and logical reasoning, and generalization toward polygons.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.8
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• pp.747-752
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• 2020

This study examines cognitive impairment, which is one of the results from social exclusion and leads to logical reasoning disorders. This study also investigate how cognitive errors called abductive inference error occur due to cognitive impairment. Present study was performed with 81 college students. Participants were randomly assigned to the group who has experienced social exclusion or to the group who has not experience the social exclusion. We analyzed how the degree of error of abductive inference differs according to the social exclusion experience. The group who has experienced social exclusion showed a higher level of abductive inference error than the group who has not experience. The abductive condition inference value of the group who has experienced social exclusion was higher in the group with the deduction condition inference value of 90% than in the group with the deduction condition inference value of 10%, and the difference was also significant. This study extended the concepts of cognitive impairments, escape theory, cognitive narrowing which are used to explain addiction behavior to human cognitive bias. Also this study confirmed that social exclusion experience increased cognitive impairment and abductive inference error. Future research directions and implications were discussed and suggested.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.7
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• pp.1248-1254
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• 2010

Authors conducted a deduction of some parameters using the magnetic equivalent circuit method and a verification study of the thrust force control algorithm of a rotary-typed small-scaled linear induction motor for a railway transit. In a LIM, it is possible to express the parameters of the magnetic equivalent circuit into a function of the shape of the secondary aluminium plate and the airgap between the LIM primary core and the secondary aluminium plate. It means that the LIM properties can be changed considerably by the shape of the secondary aluminium plate and the airgap between the LIM primary core and the secondary aluminium plate. So, authors analyzed a tendency of changes of the magnetic equivalent circuit parameters and the LIM characteristics by changing of the airgap of the secondary aluminium plate of a rotary-typed small-scaled LIM. And authors conducted a verification study of the indirect vector control algorithm with constant slip frequency by using the rotary-typed small-scaled LIM tester set on the basis of the calculated LIM parameters. Finally authors accomplished a research on applicability for LIM railway transit.

• Journal of the Society of Naval Architects of Korea
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• v.47 no.6
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• pp.782-786
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• 2010

Thrust deduction related to the prediction of power performance of a ship is rather resistance increase, and as a preliminary study for it forces upon a circular cylinder in a uniform flow of ideal fluid due to singularities located behind it are investigated. The circle theorem is used to get the complex velocity potential for the flow field under consideration, and the Blasius theorem is applied to obtain forces upon the circular cylinder. As singularities sinks, point vortices and dipoles and their combinations are treated. $\varepsilon$, standing for the strength of a singularity, and $\delta$, representing the distance between the cylinder and the singularity, are important small parameters for the resistance and lateral forces. For sinks or point vortices it is shown that the dimensionless forces upon the cylinder is O($\epsilon$) if $\epsilon$= O($\delta$) is assumed, and the same holds for dipoles if $\epsilon$= O(${\delta}^3$) is supposed. Forces upon the cylinder by a symmetric pair of sinks are greater than a single sink located at the central plane since there is an additional term due to cross effects, and the same is also valid for the case of dipole. Combination of dipole and a point vortex is also considered and a few new aspects are clarified.

• Journal of the Society of Naval Architects of Korea
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• v.56 no.6
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• pp.497-506
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• 2019

Literature survey was conducted on the 2013 Interim Guidelines for determining the minimum propulsion power to maintain the manoeuvrability of ships in adverse conditions. The International Maritime Organization (IMO) Marine Environment Protection Committee (MEPC) documents related with the Guidelines were reviewed. Compatibility of the present Guidelines can be checked by two different levels: (Level 1) minimum power lines assessment and (Level 2) simplified assessment. The IHS (Information Handling Services) sea-web data on the bulk carriers and the tankers, which were built after 2000, were used to examine the Level 1 assessment. KVLCC2 was used to examine the Level 2 assessment. Regarding the Level 2 assessment, effects of the adverse weather conditions, the added resistance due to waves, the wake fractions and the thrust deduction factors were discussed.

• The KIPS Transactions:PartB
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• v.10B no.3
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• pp.273-280
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• 2003

Recommender System can help users to find products to Purchase. A representative method for recommender systems is collaborative filtering (CF). It predict products that user may like based on a group of similar users. User information is based on user's ratings for products and similarities of users are measured by ratings. As user is increasing tremendously, the performance of the pure collaborative filtering is lowed because of high dimensionality and scarcity of data. We consider the effect of dimension deduction in collaborative filtering to cope with scarcity of data experimentally. We suggest that SVD improves the performance of collaborative filtering in comparison with pure collaborative filtering.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.470-470
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• 2010

Negative ions are generated in fusion edge plasmas, material processing plasmas, ionospheric plasmas. Analytic formulas for the deduction of the absolute density of negative ions was given by using the current-voltage(IV) characteristics of two electric probes at two different pressures [1], and negative ion density has been measured by one electric probe using the current-voltage characteristics of three different pressures [2]. Ratios of ion and electron saturation currents and electron temperatures and sheath areas of different pressures are usually incorporated into two equations with two unknowns for the negative ion density. In the previous publications, the sheath factor(sheath area, sheath density, sheath velocity) and effective masses of background ions with different pressures are qualitatively incorporated for the deduction of negative density. In this presentation, the quantitative and detailed relation of negative ion density with sheath factor and effective masses are going to be given. The effect of these parameters on the change of IV characteristics will be addressed.

• The Korean Journal of Emergency Medical Services
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• v.26 no.1
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• pp.119-127
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• 2022

Purpose: This study aimed to examine the necessity of administrative compensation insurance and claims cases during the emergency medical service process among administrative compensation insurance cases and suggests problems and improvement measures. Methods: We compared the details of administrative compensation insurance claims of 15 cities and provinces, excluding Seoul and Kwangju, from 2017 to 2020 by requesting details disclosure of the comprehensive deduction for administrative compensation in 17 cities and provinces across the country. Results: A total of 69 cases were compensated through the administrative comprehensive compensation deductions. There were 53 cases of damage that occurred at the field stage, 14 cases at the transfer and hospital stage, and two other cases. Conclusion: The 119 paramedics, which are the perpetrators, should be active in field activities and free from the psychological pressure caused by increased workload and litigation. Active compensation administration is required for damage cases occurring in the firefighting activities context.

• Journal of Venture Innovation
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• v.1 no.1
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• pp.83-98
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• 2018

This paper makes a theoretical approach to the differences between transaction tax and capital gains tax when the financial instruments are traded and imposed taxes in K-OTC market, a newly emerging off-board market. Since it is difficult to reduce risk to the level which investors would like to pursue - depending on the taxation methods of portfolio-composed financial instruments - when it comes to forming a synthetic bond to hedge risk, this paper also seeks for effective taxation methods to make this applicable. First of all, to thoroughly review the taxation balance of synthetic bonds, this paper analyzed the effects of the transaction tax and capital gains tax imposed upon synthetic bonds according to the changes in final stock price and strike price in K-OTC market, and analyzed after-tax profit differences among them depending on whether income tax deduction took place or not. As a result of the research upon the tax gap in transaction tax and capital gains tax according to the changes of final stock prices, it was shown that imposing transaction tax is more likely to be effective for some level of risk hedging with replicating portfolio considering taxation policies and financial markets, since the effect of the transaction tax has a much lower tax gap than that of capital gains tax. In addition, in relation to whether income tax deduction was permitted or not, it was proved that the effect of the transaction tax and the capital gains tax vary depending on the variation in the strike price. Above all, it was shown that if the strike price is lower than the stock price, the transaction tax will be less affected by the existence of income tax deduction than the capital gains tax, while both will be equally affected by the existence of income tax deduction if the strike price is higher than the stock price. Further study would be to demonstrate the validation of this in the K-OTC market with actual financial instruments and, also, to seek for a more systematic hedging method by using a ratio analysis approach to the calculation of the option transaction tax

• The Korean Society of Law and Medicine
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• v.16 no.2
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• pp.87-130
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• 2015

In a case in which National Health Insurance Corporation (NHIC) pays medical care expenses to a victim of a traffic accident resulting in injury or death and asks the assailant for compensation of its share in the medical care expenses, as the precedent treats the subrogation of a claim set by National Health Insurance Act the same as that set by Industrial Accident Compensation Insurance Act, it draws the range of its compensation from the range of deduction, according to the principle of deduction after offsetting and acknowledges the compensation of all medical care expenses borne by the NHIC, within the amount of compensation claimed by the victim. However, both the National Health Insurance Act and the Industrial Accident Compensation Insurance Act are laws that regulate social insurance, but medical care expenses in the National Health Insurance Act have a character of 'an underinsurance that fixes the ratio of indemnification,' while insurance benefit on the Industrial Accident Compensation Insurance Act has a character of full insurance, or focuses on helping the insured that suffered an industrial accident lead a life, approximate to that in the past, regardless of the amount of damages according to its character of social insurance. Therefore, there is no reason to treat the subrogation of a claim on the National Health Insurance Act the same as that on the Industrial Accident Compensation Insurance Act. Since the insured loses the right of claim acquired by the insurer by subrogation in return for receiving a receipt, there is no benefit from receiving insurance in the range. Thus, in a suit in which the insured seeks compensation for damages from the assailant, there is no room for the application of the legal principle of offset of profits and losses, and the range of subrogation of a claim or the amount of deduction from compensation should be decided by the contract between the persons directly involved or a related law. Therefore, it is not reasonable that the precedent draws the range of the NHIC's compensation from the principle of deduction after offsetting. To interpret Clause 1, Article 58 of the National Health Insurance Act that sets the range of the NHIC's compensation uniformly and systematically in combination with Clause 2 of the same article that sets the range of exemption, if the compensation is made first, it is reasonable to fix the range of the NHIC's compensation by multiplying the medical care expenses paid by the ratio of the assailant's liability. This is contrasted with the range of the Korea Labor Welfare Corporation's compensation which covers the total amount of the claim of the insured within the insurance benefit paid in the interpretation of Clauses 1 and 2, Article 87 of the Industrial Accident Compensation Insurance Act. In the meantime, there are doubts about why the profit should be deducted from the amount of compensation claimed, though it is enough for the principle of deduction after offsetting that the precedent took as the premise in judging the range of the NHIC's compensation to deduct the profit made by the victim from the amount of damages, so as to achieve the goal of not attributing profit more than the amount of damage to a victim; whether it is reasonable to attribute all the profit made by the victim to the assailant, while the damages suffered by the victim are distributed fairly; and whether there is concrete validity in actual cases. Therefore, the legal principle of the precedent concerning the range of the NHIC's compensation and the legal principle of the precedent following the principle of deduction after offsetting should be reconsidered.