• Journal of Information Processing Systems
• /
• 제14권4호
• /
• pp.837-850
• /
• 2018

Bitcoin is a decentralized crypto-currency, which is based on the peer-to-peer network, and was introduced by Satoshi Nakamoto in 2008. Bitcoin transactions are written by using a scripting language. The hash value of a transaction's script is used to identify the transaction over the network. In February 2014, a Bitcoin exchange company, Mt. Gox, claimed that they had lost hundreds of millions US dollars worth of Bitcoins in an attack known as transaction malleability. Although known about since 2011, this was the first known attack that resulted in a company loosing multi-millions of US dollars in Bitcoins. Our reason for writing this paper is to understand Bitcoin transaction malleability and to propose an efficient solution. Our solution is a softfork (i.e., it can be gradually implemented). Towards the end of the paper we present a detailed analysis of our scheme with respect to various transaction malleability-based attack scenarios to show that our simple solution can prevent future incidents involving transaction malleability from occurring. We compare our scheme with existing approaches and present an analysis regarding the computational cost and storage requirements of our proposed solution, which shows the feasibility of our proposed scheme.

• 정보보호학회논문지
• /
• 제17권5호
• /
• pp.3-14
• /
• 2007

본 논문에서는 강력한 의사난수 함수 관점에서 안전한 tweakable 전단사 함수 패밀리를 이용하여 연관키에 안전한 전단사 함수 패밀리를 설계할 수 있음을 보인다. 이를 이용하여 현재까지 알려진 것 중에 가장 빠르면서 연관키 공격에 안전한 전단사 함수 패밀리를 구성한다. 또한, 의사난수 함수 관점에서 안전한 적당한 유형의 함수 패밀리를 이용하여 연관키 공격에 안전한 전단사 함수 패밀리를 구성할 수 있음을 보인다. 이는 기존의 안전성이 증명된 MAC 알고리즘을 이용하면 연관키 공격에 안전한 스킴을 구성할 수 있음을 나타낸다. 끝으로, 본 논문에서는 연관키 공격에 대한 여러 안전성 개념(indistinguishability, non-malleability)을 정의하구 그들 사이의 관계를 살펴본다.

• PNF and Movement
• /
• 제6권2호
• /
• pp.51-57
• /
• 2008

Purpose : Mechanical stress activates signaling cascades and leading to a specific response of a network of signaling pathways. The purpose of this study is to review the effect of mechanical stress-induced adaptation in skeletal muscle involves a biological mechanisms. Methods : This is literature study with Pubmed, Medline and books. Results : Skeletal muscle tissue demonstrates a malleability and may adjust its metabilic response, vascularization and neuromuscular characteristic makeup in response to alteration in functional demands. The adaptation in skeletal muscle involoves a multitude of signalling mechanisms related with insuline-like growth factor, vascular endothelial growth factor, neurotrophins. Conclusions : The identification of the basic relationships underlying the malleability of skeletal muscle tissue is likely to be of relevance for our understanding with PNF technique.

• Child Health Nursing Research
• /
• 제6권2호
• /
• pp.132-143
• /
• 2000

The purpose of this correlational study was to find the correlation between the infant temperament, mother-infant interaction, and child-rearing environment. The subjects of this study were 37 dyads of healthy mothers and healthy infants. Data were collected from 15th of March to 3rd of September, 1999. Convenient sampling was done at Obstetric wards of one University hospital, and demographic data were collected before discharge. At one month and three month postpartum, we visited subject's home, and collected the data on the infant temperament, and also video taped the mother-infant interaction during feeding. In addition, child-rearing environment was checked by researcher according to HOME(Home Observation for Measurement of the Environment) at three months postpartum. Mother-infant interactions were rated according to the NCAST Feeding Scale later. Data were analyzed by window SPSS program, and correlations between the infant temperament, mother-infant interaction, and child-rearing environment were analyzed by Pearson's correlational coefficient. The results were as follows: 1. Infant temperament. 1) Among the subscales of infant temperament, mothers perceived cuddliness and amenability most positively at one month, and responsivity and amenability most positively at three months. 2) In subscale analysis of stability, amenability, responsivity, and persistence were stable with the time. 3) Significant relationships were found between the malleability and amenability, between the malleability and responsivity at one month, and also between the malleability and amenability, and between the malleability and cuddliness at three months. 2. Correlations of infant temperament and mother-infant interaction. 1) There was no significant relationship between the infant temperament and mother-infant interaction at one month. 2) There was a significant relationship between the infant temperament and mother-infant interaction at three months(r=.335, p<.05). In subscale analysis, there were significnt relationships between the total score of infant temperament and maternal sensitivity to infant's cues(r=.372, p<.05), and between the total score of infant temperament and maternal response to infant's distress (r=.331, p<.05). 3. Correlations of infant temperament and child-rearing environment. 1) There was no significant relationship between the total score of infant temperament at one month and total score of HOME at three months. In subscal analysis, the total score of infant temperament at one showed significant relationships with the organization of environment(r=.413, p<.05), and the emotional, verbal response at three months(r=.337, p<.05). 2) There was a significant relationship between the total score of infant temperament at three months and the total score of HOME at three months (r=.599, p<.01). In subscal analysis, the total score of infant temperament at three months showed significant relationships with the organization of environment(r=.410, p<.05), maternal involvement(r=.482, p,.01), and the emotional, verbal response(r=.695, p<.01) at three months. 4. Correlations of mother-infant interaction and child-rearing environment. There was a significant relationship between the maternal score of mother-infant interaction at one month and three months and the total score of HOME at three months (r=.474, p<.01; r=.452, p<.01). In conclusion, it was proved that infant temperament had significant relationships with mother-infant interaction and child-rearing environment, especially when the infants were getting older. This showed the possibility for changeability of infant teperament by the maternal factors.

• 정보보호학회지
• /
• 제8권4호
• /
• pp.5-14
• /
• 1998

본 논문에서는 공개키 암호 방식에 대한 안전성 개념들을 종합적으로 조사하고 분석한다. 의미론적 안전성(semantic security ), 구별불능 안전성(indistinguishable encryption), NM- 안전성(non-malleability)등에 대한 개념을 소개한다. 그리고 이들 개념에 공격(attack)관점의 안전성을 결합한 정의에 대해서 고찰하며, 소개한 개념들 사이의 수학적 관계를 규명한다.

• Journal of Pharmaceutical Investigation
• /
• 제29권2호
• /
• pp.127-136
• /
• 1999

In order to eliminate demerits of conventional dosage forms, dipotassium glycyrrhizate was formulated as a slim mucoadhesive film type dosage form. The mucoadhesive drug layer gel containing dipotassium glycyrrhizate was prepared using $Noveon^{\circledR}$ AA-1, hydroxypropylcellulose-M, ethylcellulose N 100 and citric acid, and the protective layer gel by using ethylcellulose N 100, $Eudragit^{\circledR}$ RS and castor oil. The viscosity of drug layer gel of mucoadhesive film was enhanced as the increased amount of $Noveon^{\circledR}$ AA-1 or hydroxypropyl cellulose-M. The drug content was unifonnly $1160{\pm}14.6\;{\mu}g$, and was varied within 3.5%. The optimum film dosage form showed a good fluidity and malleability of drug layer, with 179 g of thickness, pH 5.7, 411 min of in vitro adhesion time and 172 g in gravity adhesive strength. The release time of drug from the mucoadhesive film was significantly shorter but was delayed when polymers such as ethylcellulose was added. From these results, the new mucoadhesive film may be effective for the treatment of aphthous stomatitis.

• 보건교육건강증진학회지
• /
• 제23권1호
• /
• pp.125-141
• /
• 2006

Objective: Today The human need for health promotion and maintenance is increasing. Health professionals have a great responsibility for helping clients to practice good health behavior. We need to define compliance which is best fit in the philosophy of the health discipline. The purpose of this study is to clarify the concept of compliance. Methods: Concept analysis is the act of examining parts, phenomenon and the interrelated parts of a whole. The process of concept approach described by Walker and Avant (1995). Is this study, a concept analysis of compliance was performed to comprehensively understand and develop effective health intervention methods: Result & Conclusion: The defining attributes of compliance identified in this study are as follows; the ability to complete or perform what is needs, to be malleability, to take initiative, to be adaptability and to be flexibility. 1) Be gentle and easily changeable (Malleability) 2) To take the initiative, a first step, or move towards an end or aim (Initiative) 3) Be able to change their ideas and behavior in order to deal with new situation (Adaptability) 4) Be able to change easily and adapt to different conditions and circumstances (Flexibility) Finally, the implication of these findings for further research and health promotion intervention are discussed.

• 한국정보보호학회:학술대회논문집
• /
• 한국정보보호학회 2003년도 동계학술대회
• /
• pp.399-405
• /
• 2003

A new type of signature scheme, called NTRUSign, based on solving the approximately closest vector problem in an NTRU lattice was proposed in［7］,［8］. However no security proof against chosen messages attack has been made for this scheme. In this paper, we show that NTRUSign signature scheme contains the weakness of malleability. From this, one can derive new valid signatures from any previous message-signature pair which means that NTRUSign is not secure against strongly existential forgery.

• 대한치과보철학회지
• /
• 제41권3호
• /
• pp.351-359
• /
• 2003

Statement of problem: Regardless of any restoration, most of case, we used in screw connection between abutment and implant. For this reason, implant screw loosening has been remained problem in restorative practices. Purpose: The purpose of this study was to compare surface of coated/plated screw with titanium and gold alloy screw and to evaluate physical property of coated/plated material after scratch test in FESEM investigation Material and methods: GoldTite, titanium screw provided by 3i (Implant Innovation, USA) and TorqTite, titanium screw by Steri-Oss (Nobel Biocare, USA) and gold screw, titanium screw by AVANA (Osstem Implant, korea) - were selected for this study. Each abutment screw surface was observed at 100 times, and then screw crest, root, and slope were done more detailed numerical value, at 1000 times with FESEM. A micro-diamond needle was also prepared for the scratch test. Each abutment screw was fixed, micro-diamond scratch the surface of head region was made at constant load and then was observed central region and periphery of fine trace through 1000 times with FESEM. Results: The surface of GoldTite was smoother than that of other kinds of screw and had abundant ductility and malleability compared with titanium and gold screw. The scratch test also showed that teflon particles were exfoliated easily in screw coated with teflon. Titanium screw had a rough surface and low ductility. Conclusion: It was recommended that the clinical use of gold-plated screw would prevent a screw from loosening. CLINICAL IMPLICATIONS Clinical use of gold-plated screw would prevent a screw from loosening because it had abundant ductility and malleability compared with titanium and gold screw.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2008년도 추계학술대회A
• /
• pp.1193-1197
• /
• 2008

Bridge is Most from stay of Gantry structures part. In compliance with oneself weight of the bridge deflecting, this occurs drops the location precision of the work tool. Also accelerative at the time of gives a serious load to Y axial motors which transfer the bridge damages. The motor with high-speed transfer of location control which is accurate makes disrupt. The malleability of the bridge to maintain consequently and necessary to minimize a weight. This paper the structural FEM interpretations of the stone and the aluminum alloy with the material by which will be used in the bridge and static deflected and a candle precise plane X-Y stage optimal design with character the interpretation result.