• Journal of Broadcast Engineering
• /
• v.20 no.1
• /
• pp.92-109
• /
• 2015

Broadcast encryption is a cryptographic primitive that allows a sender to securely broadcast a message to a set of receivers. The most influential broadcast encryption system was proposed in 2001 by Naor, Naor, Lotspiech, based on a pseudo-random generator and the Subset Difference (SD) method. In this paper, we suggest a new broadcast encryption system that is based on secret sharing and SD methods. On an efficiency aspect, our system achieves O(r) transmission cost, O($log^2n$) storage cost, and O(1) computational cost for the number n of users and the number r of revoked users. Compared to O(log n) computational cost in the previous SD method, our system has the advantage that it needs only constant-sized computational cost for decryption, regardless of the number n or r. On a security aspect, our system can achieve tighter security reduction than the previous SD method and the gap of security loss is about O(n log n). Moreover, our result shows that it is possible to give the effect of the SD method while using an information-theoretically secure key distribution technique as in the Complete Subtree method.

• Journal of Hospice and Palliative Care
• /
• v.12 no.2
• /
• pp.61-71
• /
• 2009

Purpose: The purpose of this study was to develop a CD program of applied logotherapy for psycho spiritual care of late adolescents with terminal cancer. Methods: Keller & Song's ARCS theory and a model for developing learning materials was applied to develop this program composed four distinct phases: planning, designing, developing, and evaluation stages. Results: This program was entitled 'Finding meaning in my life' and consisted of 5 sessions and its educational contents were made up as follows: "First Secret" is 'learning three natures of the human mind', "Second Secret" is 'learning creative values first method to find meaning of life', "Third Secret" is 'learning experiential value as second method to find meaning of life', "Fourth Secret" is 'learning attitudinal value as third method to find meaning of life', and "Fifth Secret" is 'Becoming the master of my life'. The sub-menu was made up of 'Beginning', 'Opening mind', 'Learning'. 'Laughing Song', 'Experiencing'. Conclusion: This CD program applied logotherapy with flash animation technique as an emotional and spiritual nursing intervention program for easier and more scientific application in pediatric oncology and hospice care area.

• Journal of Korea Multimedia Society
• /
• v.23 no.6
• /
• pp.738-746
• /
• 2020

In this paper, we propose an indirect PIN entry method that provides enhanced security against smudge, recording, and thermal attacks. Conventional mobile PIN entry methods use on-screen numeric keypad for both use of display and entry. Thus These methods are vulnerable to aforementioned attacks. In our method, passcode is same as that of the conventional PIN entry methods, and that is user-friendly way for mobile device users. Therefore, our method does not reduce user convenience which is one of the advantages of the conventional methods. In addition, our method is not a method of directly touching the on-screen numeric keypad for entering passcode like the conventional PIN methods. Unlike the conventional methods, our method uses an indirect passcode entry method that applied a passcode indicating key. According to the performance comparison result, proposed method provides user convenience similar to the conventional methods, and also provides a higher level of security and safety against recording, smudge, and thermal attacks than the conventional methods.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.49 no.9
• /
• pp.55-64
• /
• 2012

Until now, Side Channel Attack has been known to be effective to crack decrypt key such as smart cards, electronic passports and e-ID card based on Chip. Combination of Masking and shuffling methods have been proposed practical countermeasure. Newly, S.Tillich suggests biased-mask using template attack(TA) to attack AES with masking and shuffling. However, an additional assumption that is acquired template information previously for masking value is necessary in order to apply this method. Moreover, this method needs to know exact time position of the target masking value for higher probability of success. In this paper, we suggest new practical method called Biasing Power Analysis(BPA) to find a secret key of AES based on masking-shuffling method. In BPA, we don't use time position and template information from masking value. Actually, we do experimental works of BPA attack to 128bit secret key of AES based on masking-shuffling method performed MSP430 Chip and we succeed in finding whole secret key. The results of this study will be utilized for next-generation ID cards to verify physical safety.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.25 no.6
• /
• pp.1485-1494
• /
• 2015

Traditionally, data hiding has been done mainly in such a way that insert the data into the large-capacity multimedia files. However, the document files of the previous versions of Microsoft Office 2003 have been used as cover files as their structure are so similar to a File System that it is easy to hide data in them. If you open a compound-document file which has a secret message hidden in it with MS Office application, it is hard for users who don't know whether a secret message is hidden in the compound-document file to detect the secret message. This paper presents an analysis of Compound-File Binary Format features exploited in order to hide data and algorithms to detect the data hidden with these exploits. Studying methods used to hide data in unused area, unallocated area, reserved area and inserted streams led us to develop an algorithm to aid in the detection and examination of hidden data.

• The KIPS Transactions:PartC
• /
• v.17C no.5
• /
• pp.399-406
• /
• 2010

Many problems are arisen due to the weakness in the security and invasion to privacy by malicious attacker or internal users while various data services are available in ubiquitous network environment. The matter of controlling security for various contents and large capacity of data has appeared as an important issue to solve this problem. The allocation methods of Ito, Saito and Nishizeki based on traditional polynomial require all shares to restore the secret information shared. On the contrary, the secret information can be restored if the shares beyond the threshold value is collected. In addition, it has the effect of distributed DBMS operation which distributes and restores the data, especially the flexibility in realization by using parameters t,v,k in combinatorial design which has regularity in DB server and share selection. This paper discuss the construction of new share allocation method and data distribution/storage management with the application of matrix structure of t-(v,k,1) design for allocating share when using secret sharing in management scheme to solve the matter of allocating share.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.28 no.5
• /
• pp.1035-1045
• /
• 2018

Recently, with the development of IT technology, authentication methods of users using cloud services have been diversified. However, research on providing authentication information of a user using a cloud service securely according to authority has not been make until now. In this paper, we propose a key establishment protocol which can perform split authentication using secret key and access control key according to the role authority of user in Intra cloud environment. The proposed protocol generates the access control key and secret key of the user by using the attributes of the user and the generated random number($t_1$, $t_2$), and classifies the roles according to the user's authority after generating the key. Unnecessary operation processes can be reduced. As a result of the performance evaluation, the proposed protocol guarantees the security against various type of attacks that may occur in the cloud environment because the user is authenticated by dividing the access control key and secret key. The size of the ciphertext used to establish the key could be reduced by ${\sum}+1$ more than the existing protocol.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.29 no.1
• /
• pp.27-33
• /
• 2019

Objective: This study analyzed the status of the application of trade secrets in MSDSs according to size and type of industry. The contents of the MSDS non-public approval policy are summarized. We suggest proactive improvement requirements related to the operation of the MSDS non-public approval policy. Methods: To review this subject, we selected 153 manufacturers and six importers in such fields as organic chemical production. The trade secrets application status and ratio (%) of MSDSs by industry size and industry classification were investigated. Improvements toward a proactive system related to the operation of the MSDS non-public approval policy under the Occupational Safety and Health Act(OSHA) were summarized. Results and Conclusions: According to the results, the trade secret ratio in MSDSs by industry size was 33% in workplaces with less than 50 employees, 23.1% in workplaces with more than 50 but less than 100 workers, 73% in workplaces with more than 100 workers, and 83.4% in workplaces with 300 or more workers. For the trade secret writing rate for MSDSs by industry, the highest was MOCCP (Manufacture of ink, paint, coating and similar products) at 80.9%. MOC (Manufacture of other chemicals) was the lowest at 16.2%. We propose four proactive efforts to minimize the administrative burden of implementation of the MSDS non-public approval policy. The results of this study can be used as basic data for policy improvements to make more effective use of MSDS.

• ETRI Journal
• /
• v.37 no.3
• /
• pp.512-522
• /
• 2015

Recent developments in identity-based cryptography (IBC) have provided new solutions to problems related to the security of mobile ad hoc networks (MANETs). Although many proposals to solve problems related to the security of MANETs are suggested by the research community, there is no one solution that fits all. The interdependency cycle between secure routing and security services makes the use of IBC in MANETs very challenging. In this paper, two novel methods are proposed to eliminate the need for this cycle. One of these methods utilizes a key pool to secure routes for the distribution of cryptographic materials, while the other adopts a pairing-based key agreement method. Furthermore, our proposed methods utilize threshold cryptography for shared secret and private key generation to eliminate the "single point of failure" and distribute cryptographic services among network nodes. These characteristics guarantee high levels of availability and scalability for the proposed methods. To illustrate the effectiveness and capabilities of the proposed methods, they are simulated and compared against the performance of existing methods.

• Journal of the Korean Society of Costume
• /
• v.52 no.6
• /
• pp.71-83
• /
• 2002

The purpose of this study was to investigate the causal relationships of need, self-esteem, body satisfaction on aesthetic surgery attitude of female. The method of the study was survey research by using questionnaires. Subjects were 813 females of 10's to 40's living in Daejeon Metropolitan City and Gongju City, Chungchungnamdo. Statistical analysis methods were one-way ANOVA. Duncan's multiple range test, Pearson's correlation coefficient, and multiple regression analysis. The results of the study were as follows. Women with lower body satisfaction and self-esteem had a tendency to keep the secret of aesthetic surgery. Women in higher social class and having higher need for dominance showed also strong tendency to keep the secret of aesthetic surgery. Women with lower body satisfaction and having higher needs for achievement and exhibition appreciated the value of aesthetic surgery more. Women with lower body satisfaction and self-esteem but with higher need for exhibition and dominance were more willing to confirm the aesthetic surgery Women with higher need for dominance but with lower self-esteem and body satisfaction were more willing to undergo aesthetic surgery in spite of high cost of surgery. Women having lower self-esteem, lower need for achievement, and lower body satisfaction were more willing to admit the risk tolerance of aesthetic surgery. As a conclusion, need, self-esteem, and body satisfaction constituted important characteristics which could affect aesthetic surgery attitude directly. Women having higher need were more willing to admit the change of body shape via aesthetic surgery.