• Journal of the Korea Society of Computer and Information
• /
• v.27 no.2
• /
• pp.203-212
• /
• 2022

In this paper, we propose to identify the factors and satisfaction of the selection of University and departments of One university freshmen. Research subjects were 499 freshmen in 2021 at K University located in G city. The data were analyzed by descriptive statistics, t-test, ANOVA, Scheffe' test and pearson's correlation coefficient using SPSS WIN 18.0. The results of this study showed that the internet/SNS was the highest in university information media, the school teacher was the highest in information provider, and the employment rate had the most impact on university registration decision. The University satisfaction score was 3.43, and there was a significant difference in gender(t=5.527, p=.019) and admission type(F=5.527, p<.001). The department satisfaction was 3.86 and there was a significant difference in the admissions type(F=3.004, p=.018). Univdrsity satisfaction and Department satisfaction showed a significant positive correlation(r=5.527, p<.001). Universities should improve their competitiveness through systematic admission information system.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.13 no.4
• /
• pp.99-106
• /
• 2017

With the advent of virtual money such as bit coins, interest in the block chain is increasing. Block Chain is a technology that supports Distributed Ledger and is a versatile technology applicable to various fields. Currently, the block chain is conducting research for various applications such as virtual money, trade finance, marketplace, power market, image contents service, and IoT. The technologies that make up the block chain are smart contract, digital signature/hash function and consensus algorithm. And these technologies operate on P2P networks. In this paper, we have studied e-mail system based on the ethereum which is one of the block chain based technologies. Most legacy mail systems use SMTP and the POP3/IMAP protocol to send and receive e-mail, and e-mail use S/MIME to protect the e-mail. However, S/MIME is vulnerable to DDoS attacks because it is configured centrally. And it also does not provide non-repudiation of mail reception. To overcome these weaknesses, we proposed an e-mail system model based on ethereum. The proposed model is able to cope with DDoS attack and forgery prevention by using block chain based technology, and reliable recording and management among block chain participants are provided, so that it is possible to provide a non-repudiation function of e-mail transmission and reception.

• International journal of advanced smart convergence
• /
• v.6 no.3
• /
• pp.29-37
• /
• 2017

The current behavior recognition system don't match data formats between sensor data measured by user's sensor module or device. Therefore, it is necessary to support data processing, sharing and collaboration services between users and behavior recognition system in order to process sensor data of a large capacity, which is another formats. It is also necessary for real time interaction with users and behavior recognition system. To solve this problem, we propose fog cloud based behavior recognition system for human body sensor data processing. Fog cloud based behavior recognition system solve data standard formats in DbaaS (Database as a System) cloud by servicing fog cloud to solve heterogeneity of sensor data measured in user's sensor module or device. In addition, by placing fog cloud between users and cloud, proximity between users and servers is increased, allowing for real time interaction. Based on this, we propose behavior recognition system for user's behavior recognition and service to observers in collaborative environment. Based on the proposed system, it solves the problem of servers overload due to large sensor data and the inability of real time interaction due to non-proximity between users and servers. This shows the process of delivering behavior recognition services that are consistent and capable of real time interaction.

• 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 the Korea Society of Computer and Information
• /
• v.24 no.12
• /
• pp.119-126
• /
• 2019

Korea is rapidly becoming an aging society due to lower birth rate and longer life expectancy. As elderly diseases are of a serious concern, the number of patients with dementia has been increasing significantly. For now, it has become a nationwide problem, as dementia is difficult to manage and requires a lot of social costs. To solve this, an IoT device has been devised that efficiently screens Mild Cognitive Impairment(MCI), the early stage of dementia. To design and implement the device, the latest IoT technology is introduced, the optimized Korean Version of Hasegawa Dementia Scale Revised(K-HDS) is utilized, and convenient service scenario with user-friendly design is applied. As a result, the symptoms of MCI have been screened quickly with convenient operation, which lead to the healthier society by the prevention of dementia.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2001.05a
• /
• pp.125-128
• /
• 2001

Earlier efforts on optical access concentrated on the design of PONs for the collection and distribution portion of the access network. PON architecture is very simple but it requires MAC protocol for control of upstream traffic. This paper proposes a MAC protocol for a broadband access network using an ATM Passive Optical Network supporting CBR/rtVBR, nrtVBR, ABR aild UBR traffic. For the proposed MAC scheme, we present grant field format, minislot format, and bandwidth allocation algorithm.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2007.10a
• /
• pp.917-920
• /
• 2007

In this paper, we designed the authentication system for home network service and applied it to actual sensor nodes. SNEP protocol of SPINS provides confidentiality of data and authentication. We achieved authentication key, encryption and decryption applied RCS encryption algorithm of SNEP. In addition, we used pair-wise key pre-distribution for prevention of authentication sniffing in wireless sensor network. The experiment environment consists of a base station receiving data and sensor nodes sending data. Each sensor nodes sends both the data and encrypted authentication key to the base station. The experiences had shown that the malfunction doesn't happen in communication among other groups. And we confirmed in tests that the system is secure when a sensor having malicious propose is added.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.31 no.10B
• /
• pp.900-908
• /
• 2006

This paper studied on the future market competitive structure among mobile multimedia services that offer a variety of multimedia services and contents through wireless networks. In the past, forecasting methods based on market data would be used popularly in telecommunications industry. However, methods must focus on not market data but customer preferences. In this reason, paper use to forecast the market competitive structure and offer firm strategies and policies using a customer choice probability model.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.15 no.2
• /
• pp.617-636
• /
• 2021

This paper presents a privacy-preserving data aggregation scheme deals with the multidimensional data. It is essential that the multidimensional data is rarely mentioned in all researches on smart grid. We use the Paillier Cryptosystem and blinding factor technique to encrypt the multidimensional data as a whole and take advantage of the homomorphic property of the Paillier Cryptosystem to achieve data aggregation. Signature and efficient batch verification have also been applied into our scheme for data integrity and quick verification. And the efficient batch verification only requires 2 pairing operations. Our scheme also supports fault tolerance which means that even some smart meters don't work, our scheme can still work well. In addition, we give two extensions of our scheme. One is that our scheme can be used to compute a fixed user's time-of-use electricity bill. The other is that our scheme is able to effectively and quickly deal with the dynamic user situation. In security analysis, we prove the detailed unforgeability and security of batch verification, and briefly introduce other security features. Performance analysis shows that our scheme has lower computational complexity and communication overhead than existing schemes.

• Journal of the Korea Society of Computer and Information
• /
• v.14 no.1
• /
• pp.127-134
• /
• 2009

Recently, much research have been done on ubiquitous computing models in advanced countries as well as in Korea. Ubiquitous computing is defined as a computing environment that isn't bounded by time and space. Different kinds of computers are embedded in artifacts, devices, and environment, thus people can be connected everywhere and every time. To recognize user's emotion, facial expression, temperature, humidity, weather, and lightning factors are used for building ontology. Ontology Web Language (OWL) is adopted to implement ontology and Jena is used as an emotional inference engine. The context-awareness service infrastructure suggested in this research can be divided into several modules by their functions.