• Education of Primary School Mathematics
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• v.16 no.2
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• pp.123-145
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• 2013

This study was expected to yield the meaningful conclusions from the experimental group who took lessons based on inductive activities using GeoGebra at the beginning of proof learning and the comparison one who took traditional expository lessons based on deductive activities. The purpose of this study is to give some helpful suggestions for teaching proof to mathematically gifted elementary students. To attain the purpose, two research questions are established as follows. 1. Is there a significant difference in proof abilities between the experimental group who took inductive lessons using GeoGebra and comparison one who took traditional expository lessons? 2. Is there a significant difference in proof attitudes between the experimental group who took inductive lessons using GeoGebra and comparison one who took traditional expository lessons? To solve the above two research questions, they were divided into two groups, an experimental group of 10 students and a comparison group of 10 students, considering the results of gift and aptitude test, and the computer literacy among 20 elementary students that took lessons at some education institute for the gifted students located in K province after being selected in the mathematics. Special lesson based on the researcher's own lesson plan was treated to the experimental group while explanation-centered class based on the usual 8th grader's textbook was put into the comparison one. Four kinds of tests were used such as previous proof ability test, previous proof attitude test, subsequent proof ability test, and subsequent proof attitude test. One questionnaire survey was used only for experimental group. In the case of attitude toward proof test, the score of questions was calculated by 5-point Likert scale, and in the case of proof ability test was calculated by proper rating standard. The analysis of materials were performed with t-test using the SPSS V.18 statistical program. The following results have been drawn. First, experimental group who took proof lessons of inductive activities using GeoGebra as precedent activity before proving had better achievement in proof ability than the comparison group who took traditional proof lessons. Second, experimental group who took proof lessons of inductive activities using GeoGebra as precedent activity before proving had better achievement in the belief and attitude toward proof than the comparison group who took traditional proof lessons. Third, the survey about 'the effect of inductive activities using GeoGebra on the proof' shows that 100% of the students said that the activities were helpful for proof learning and that 60% of the reasons were 'because GeoGebra can help verify processes visually'. That means it gives positive effects on proof learning that students research constant character and make proposition by themselves justifying assumption and conclusion by changing figures through the function of estimation and drag in investigative software GeoGebra. In conclusion, this study may provide helpful suggestions in improving geometry education, through leading students to learn positive and active proof, connecting the learning processes such as induction based on activity using GeoGebra, simple deduction from induction(i.e. creating a proposition to distinguish between assumptions and conclusions), and formal deduction(i.e. proving).

• Fashion & Textile Research Journal
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• v.12 no.6
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• pp.755-763
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• 2010

This study was intended to identify the persuasion effects according to social proof message type and product type in the context of online cosmetic advertising. For the experiment, 4 stimuli were developed as experimental stimuli for the 2(social proof message type: attitudinal social proof message, behavioral social proof message)${\times}$2(product type: hedonic product, utilitarian product) factorial design. A total of 160 questionnaires allocating forty students to each group were distributed. The results were as follows. First, behavioral social proof message showed more effective than attitudinal social proof message in advertisement attention, click-through intention and purchase intention. Second, utilitarian product showed more effective than hedonic product in advertisement attention, click-through intention and purchase intention. Third, there was interaction effect according to social proof message type and product type on the aspect of click-through intention.

• Journal of Educational Research in Mathematics
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• v.19 no.2
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• pp.185-206
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• 2009

In the study, I conducted the teaching experiment designed to instruct proof to four 7th grade students by utilizing the analysis method. As the results of this study I could identified that it is effective to teach and learn to find proof methods using the analysis. The results of the study showed that four 7th grade students succeeded in finding the proof methods by utilizing the analysis and representing the proof after 15 hours of the teaching experiment. In addition to the difficulties that students faced in learning proof utilizing the analysis were related to the search for the light conditions for triangles to be congruent, symbolic representation of the proof methods, reinterpretation of drawings given in the proof problems.

• The Korean Society of Law and Medicine
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• v.9 no.1
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• pp.9-56
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• 2008

The medical practice does not always get a satisfatory result since the disease progress of patients are depended on patients' physical constitution and the doctors cannot control the outcomes about patients' physiological and biological reaction after the treatment. Moreover, the medical practice may bring wrong result fatalistically because of the unpredictablility of life. To demand for compensation of the damage to the doctors about these wrong result, the patient side holds the burden of proof that is between medical practice and demage, and there is damage from doctor's malpractice according to the accepted theory about the fundamental principle of distribution of the burden of proof. This falls not only under the liability of Tort Law, but also liability of Contract Law. However, the patient may be in difficult situation to prove the malpractice of doctors since he or she cannot recognize the facts because he or she was in unconscious while the medical practice was conducted, or they cannot judge precisely even though they recognize the facts. Nevertheless, the lawsuits against medical malpractice are the field that never achieves the equality of arms since the most of the evidence belong to the doctor's side. Hence, to maintain the principle of the equality of arms under the constitution, the theory leads to alleviate the burden of proof that patients hold. However, the doctors cannot be asked for the burden of proof that they conduct medical practice without errors. Because the doctors may experience difficulty to prove their innocence as the patients because of the unique characteristic that medical practices have. Therefore, the methods of the alleviation of the patient's burden of proof should have the equality of arms and the equal opportunity between the patients and the doctors with the evaluation of the justifiable interest from both the patients and the doctors. As the methods of the alleviation of the burden of proof, the alleviation of the demands and the degree of the burden of proof or resolutely the conversion of the burden may be considered. However, Recognizing the exception from general principle with converting the burden of proof is not proper in principle because the doctors may experience difficulty of the proof as the patients may have. If the difficulty of proof can be resolved by alleviating of the demands and the degree of the burden of proof, it is more desirable resolution rather than converting the burden of proof.

• The Korean Society of Law and Medicine
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• v.15 no.2
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• pp.435-459
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• 2014

Supreme Court of Korea has been mitigating the burden of proof on the malpractice and causal relation by a patient in accordance with the practical transfer of such burden of proof on causal relation as well as relieving a doctor's burden of proof on mistake in the civil damage claim suits on the malpractice. However, a prosecutor shall strictly prove the causal relation between malpractice and unfavorable results as well as a doctor's mistake in the criminal cases for making a doctor accept the professional negligence resulting in death or injury in accordance with In Dubio Pro Reo principles. Furthermore, it shall not be allowed to relieve the burden of proof on malpractice and causal relation which has been frequently applied in the civil proceedings. Nevertheless, it was widely known that the front-line courts accepted the malpractice and causal relation by quoting the legal principles on relieving the burden of proof on malpractice and causal relation applied in the civil cases even in criminal cases with no or insufficient proof on malpractice or causal relation. However, the latest precedents in Supreme Court explicitly declared the opinion that there was no reason to apply the legal principle to relieve the burden of proof on the malpractice and causal relation in the criminal cases requiring the proof 'which doesn't cause any reasonable doubt' on malpractice and causal relation in accordance with the legal principles 'favorable judgment for a defendant in case of any doubt' on the basis of the strict principle of 'nulla poena sine lege.' Accordingly, Supreme court definitely clarified that there would be no reason to relieve the burden of proof on malpractice and causal relation in criminal cases by reversing several original judgments accepting malpractice and causal relation even though there were no strict evidence.

• School Mathematics
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• v.5 no.4
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• pp.401-420
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• 2003

We have many problems in the teaching and learning of proof, especially in the demonstrative geometry of middle school mathematics introducing the proof for the first time. Above all, it is the serious problem that many students do not understand the meaning of proof. In this paper we intend to show that teaching the meaning of proof in terms of historic-genetic approach will be a method to improve the way of teaching proof. We investigate the development of proof which goes through three stages such as experimental, intuitional, and scientific stage as well as the development of geometry up to the completion of Euclid's Elements as Bran-ford set out, and analyze the teaching process for the purpose of looking for the way of improving the way of teaching proof through the historic-genetic approach. We conducted lessons about the angle-sum property of triangle in accordance with these three stages to the students of seventh grade. We show that the students will understand the meaning of proof meaningfully and properly through the historic-genetic approach.

• Journal of Korean Association for Spatial Structures
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• v.12 no.2
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• pp.55-63
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• 2012

This study is about earthquake-proof reinforcement through structural function evaluation of an school building. The purpose of this study is to comparatively analyze structure reinforcement measures in consideration of safety and usability through structural function evaluation of school buididng, to offer rational measures for earthquake-proof function and to provide help in maintaining safe structures against earthquake. For this purpose, was selected for this study as an existing school building, earthquake-proof function evaluation was conducted, and measures to reinforce earthquake-proof function was offered. As for the research method, the first and the second earthquake-proof function evaluations were conducted which is an existing reinforced concrete school building. Through the abovementioned methods, earthquake-proof function evaluation were conducted, the results were analyzed and the measure to reinforce earthquake-proof function were offered(Steel damper, Carbon plate stiffeners). The offered measure to reinforce earthquake-proof function was applied to the subject structure, and comprehensive results were derived from earthquake-proof function evaluation regarding before and after earthquake-proof function reinforcement.

• The Korean Journal of Community Living Science
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• v.22 no.4
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• pp.615-621
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• 2011

This study was conducted to evaluate of the protection efficiency in each part of developed pesticide-proof clothes by repeated washings. We investigated the effect of repeated laundering on mechanical properties of pesticide-proof clothes (not washed vs 5 times washed). We also examined pesticide infiltration rate into the pesticide-proof clothes by repeated laundering. The patches(TCL paper, surface area 50cm2)were attached to the inside of pesticide-proof clothes(head, chest, right upper-arm, right forearm, left thigh, left calf, back) which subjects had dressed in during pesticide spraying. The patches were detached from working clothes after work. For the extraction of pesticide in pesticide-proof clothes, sonication was applied for 30 min with methanol. The gas chromatography/mass spectrometry (GC/MS) was applied to identify the pesticide component. The results of this study are as follows: The force strength, water-vapour resistance and surface wetting resistance of pesticide-proof clothes decreased 5 times more in washed clothes. The concentration of pesticide was the highest in the head area of pesticide-proof clothes. In seven parts of TLC paper attached to the pesticide proof clothes, the concentration of pesticide was higher in the left thigh. The penetration part and concentration of pesticide increased as washing was repeated. Therefore the conclusion which can be drawn from this study is this: protection efficiency of pesticide-proof clothes decrease by repeated washings.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.19 no.6
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• pp.83-92
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• 2009

Ari Juels proposed Yoking-Proof protocol for authenticating multiple tags simultaneously using RFID system. Because common Yoking-Proof methods authenticate by using MAC (Message Authentication Code), it is difficult to apply them to inexpensive tags. It is also difficult to implement common hash functions such as MD5 in inexpensive tags. So, Ari Juels also proposed a lightweighted Yoking-Proof method with only 1 authentication. However, Minimalist MAC, which is a lightweighted MAC used in the proposed method is for single-use, and the proposed structure is vulnerable to replay attacks. Therefore, in this study, the minimalist MAC using Lamport's digital signature scheme was adopted, and a new type of Yoking-Proof protocol was proposed where it uses tags that are safe from replay attacks while being able to save multiple key values.

• School Mathematics
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• v.4 no.1
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• pp.1-13
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• 2002

The purpose of this study is to investigate the reasons and backgrounds of drawing auxiliary lines in the proof of geometry. In most of proofs in geometry, drawing auxiliary lines provide important clues, thus they play a key role in deductive proof. However, many student tend to have difficulties of drawing auxiliary lines because there seems to be no general rule to produce auxiliary lines. To alleviate such difficulties, informal activities need to be encouraged prior to draw auxiliary lines in rigorous deductive proof. Informal activities are considered to be contrasting to deductive proof, but at the same time they are connected to deductive proof because each in formal activity can be mathematically represented. For example, the informal activities such as fliping and superimposing can be mathematically translated into bisecting line and congruence. To elaborate this idea, some examples from the middle school mathematics were chosen to corroborate the relation between informal activities and deductive proof. This attempt could be a stepping stone to the discussion of how to teach auxiliary lines and deductive reasoning.