• Journal of KIISE:Computer Systems and Theory
• /
• v.30 no.3_4
• /
• pp.117-129
• /
• 2003

In this paper, we propose advanced parallel join algorithm to efficiently process join operation on hypercube systems. This algorithm uses a broadcasting method in processing relation R which is compatible with hypercube structure. Hence, we can present optimized parallel join algorithm for that hypercube structure. The proposed algorithm has a complete solution of two essential problems - load balancing problem and data skew problem - in parallelization of join operation. In order to solve these problems, we made good use of the characteristics of clustering effect in the algorithm. As a result of this, performance is improved on the whole system than existing algorithms. Moreover. new algorithm has an advantage that can implement non-equijoin operation easily which is difficult to be implemented in hash based algorithm. Finally, according to the cost model analysis. this algorithm showed better performance than existing parallel join algorithms.

• Journal of Korea Entertainment Industry Association
• /
• v.15 no.7
• /
• pp.249-257
• /
• 2021

Recently, interest and demand for facial information processing technology that can provide non-face-to-face identity authentication and access management service using smart devices, which is an essential environmental improvement for multi-use facilities, is increasing as a way to prevent the spread of infectious diseases worldwide and to cope with social measures. This study defines a multi-use facility classification system and applied service field to establish a continuous access control system, and measures to improve the usability of the service platform considering scalability through a dual access control system and personal/measurement information type analysis, and accordingly We would like to propose a service roadmap. In addition, it aims to improve the physical access management system service platform, which is a multi-use facility application service that requires one-time and multiple-use authentication according to usage. It is expected that the methodology of this study can be applied as a service platform of a logical access control system type in the future.

• Journal of KIISE:Computing Practices and Letters
• /
• v.8 no.5
• /
• pp.583-589
• /
• 2002

The Internet is absolutely contributed to information telecommunication revolution nowadays. Realizing local network at the various type of buildings such as a company and a university, ethernet is used for subnet and FDDI, ATM are used for backbone mainly in order to get internet services. Processing TCP/IP protocol suite and analyzing the protocol exactly is essential to detecting the problem occurring in the network and developing communication equipment. This paper presents implementation of ethernet LAN protocol analyser which monitors and simulates ICP/IP protocol suite carrying the Internet and non-Internet protocol such as Netware and NetBIOS. MS window98 and visual C are used for development environment and application program operates on the NDIS firmware. The performance analysis on the proposed system is carried out as monitoring and simulating the traffic over LAN of a university. In the result of monitoring the system, the processing time of a packet captured over the LAN is about 1.5ms. In case of simulating the system, the processing time to be taken carrying out TCP connection and disconnection once is packet is about 8.6ms. The performance analysis of monitoring and simulation results satisfies with 10 Mbps ethernet LAN environment.

• The KIPS Transactions:PartD
• /
• v.15D no.1
• /
• pp.121-130
• /
• 2008

In line with the enhanced weight and variety of electronic commerce in business activities, new type of payment settlement and banking system which will enable to store, create and transfer values from the existing method of payment settlement is highly required. Cyber Banking system draws strong attention being the solution of there requirements. The existing Cyber Banking system has the difficulty of operation, administration, in addition to the problem of initial facility investment of big amount, resulted from the usage of the current business process. As the existing Cyber Bank system is unable to carry out the function of storing, creating, and transferring values due to the adoption conventional credit card system instead of the application of non-stop payment system between the seller and buyer. As a result, current Cyber Bank system still imply the deficiency of non-performing cash payment function on internet. This paper describes (1) an integrated application process, One Process One Input (OPOI) which is essential for software development of the Cyber Bank, (2) an application process of payment settlement system to be applied to the electronic commerce in Internet. And then, with these for a basis, (3) design and implementation of payment settlement system through CyberBank for Electronic Commerce. Consequently, by means of this suggested process, we could attempt to solve the problem of existing Cyber Bank system and further to explore the possibility of advanced Cyber Banking being the non-stop payment settlement system. The effectiveness of this suggested system has been practically confirmed.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.21 no.8
• /
• pp.1540-1546
• /
• 2017

Digital image processing is widely used in various fields including the military, medical, image recognition system, robot and commercial sectors. But in the process of acquiring and transmitting digital images, noise is generated by various external causes. There are various types of general noise depending on the cause and form, but AWGN and impulse noise is one of the leading methods. Removing noise during image processing is essential to the pre-treatment process such as segmentation, image recognition and characteristic extraction. As such, this paper suggests an algorithm that distinguishes the non-edge area and edge area using the Canny edge to apply different filters to different areas in order to effectively remove noise from the image. To verify the effectiveness of the suggested algorithm, it was compared against existing methods using zoom images, edge images and PSNR(peak signal to noise ratio).

• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.44 no.5
• /
• pp.45-54
• /
• 2007

Time/frequency analysis has been extensively used in biomedical signal processing. By extracting some essential features from the electro-physiological signals, these methods are able to determine the clinical pathology mechanisms of some diseases. However, this method assumes that the signal should be stationary, which limits its application in non-stationary system. In this paper, we develop a new signal processing method using Hilbert-Huang Transform to perform analysis of the nonlinear and non-stationary ventricular fibrillation(VF). Hilbert-Huang Transform combines two major analytical theories: Empirical Mode Decomposition(EMD) and the Hilbert Transform. Hilbert-Huang Transform can be used to decompose natural data into independent Intrinsic Mode Functions using the theories of EMD. Furthermore, Hilbert-Huang Transform employs Hilbert Transform to determine instantaneous frequency and amplitude, and therefore can be used to accurately describe the local behavior of signals. This paper studied for Return Of Spontaneous Circulation(ROSC) and non-ROSC prediction performance by Support Vector Machine and three parameters(EMD-IF, EMD-FFT) extracted from ventricular fibrillation ECG waveform using Hilbert-Huang transform. On the average results of sensitivity and specificity were 87.35% and 76.88% respectively. Hilbert-Huang Transform shows that it enables us to predict the ROSC of VF more precisely.

• KIPS Transactions on Computer and Communication Systems
• /
• v.10 no.1
• /
• pp.15-28
• /
• 2021

As the social distance has been strengthened by the COVID-19 Pandemics, telecommuting has spread, and government agencies have also begun telecommuting since March and are still maintaining a certain level. The Government's remote work service, Government Virtual Private Network (GVPN), which is essential to telecommuting of government agencies, is expected to cause a number of problems with the rapid increase in users in a short period of time. Therefore, a survey and statistical analysis were conducted to analyze the impact of the quality factors of GVPN on the users' satisfaction to the public officials of the government departments who are directly using it, and based on these results, we intend to derive the implications necessary for the improvement of GVPN for remote work in preparation for the full-fledged spread of the non-contact era.

• The KIPS Transactions:PartC
• /
• v.15C no.4
• /
• pp.245-252
• /
• 2008

An emergency service over Voice over IP (VoIP) network is an essential condition, like the existing telecommunication services. To support for the emergency services, standardization works have been performed. The National Emergency Number Association (NENA) has been developing the framework and procedures for an emergency service for Non-IP based network, rather than protocols. In contrast, the Internet Engineering Task Force (IETF) has been only focused on end-to-end IP-based emergency calls. The NENA architecture is incompatible with the IETF protocols. To solve the problem, we design and implement a SIP-based VoIP emergency system by adopting the NENA architecture and by applying IETF protocols, for both IP-based Pubic Safety Answering Point (PSAP) and PSTN-based PSAP. It is implemented and tested under UNIX environment.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.27 no.7
• /
• pp.1038-1043
• /
• 2021

Guaranteed seafarer wage payment is essential to ensure a stable supply of seafarers. However, disputes over non-payment of wages to seafarers often occur. In this study, an automatic wage payment system was designed using a blockchain-based smart contract to resolve the problem of seafarers' wage arrears. The designed system consists of an information register, a matching processing unit, a review rating management unit, and wage remittance before deploying smart contracts. The matching process was designed to send an automatic notification to seafarers and shipowners if the sum of the weight of the four variables, namely wages, ship type/fishery, position, and license, exceeded a pre-defined threshold. In addition, a review rating management system, based on a combination of mean and median, was presented to serve as a medium to mutually fulfill the normal working conditions. The smart contract automatically fulfills the labor contract between the parties without an intermediary. This system will naturally resolve problems such as fraudulent advance payment to seafarers, embezzlement by unregistered employment agencies, overdue wages, and forgery of seafarers' books. If this system design is commercialized and institutionally activated, it is expected that stable wages will be guaranteed to seafarers, and in turn, the difficulties in human resources supply will be solved. We plan to test it in a local environment for further developing this system.

• KIPS Transactions on Computer and Communication Systems
• /
• v.10 no.6
• /
• pp.173-180
• /
• 2021

Non Orthogonal Multiple Access (NOMA) is a technology to guarantee the explosively increased Quality of Service(QoS) of users in 5G networks. NOMA can remove the frequent orthogonality in Orthogonal Multiple Access (OMA) while allocating the power differentially to classify user signals. NOMA can guarantee higher communication speed than OMA. However, the NOMA has one disadvantage; it consumes a more energy power when the distance increases. To solve this problem, relay nodes are employed to implement the cooperative NOMA control idea. In a cooperative NOMA network, relay node participations for cooperative communications are essential. In this paper, a new bandwidth allocation scheme is proposed for cooperative NOMA platform. By employing the idea of Vickrey-Clarke-Groves (VCG) mechanism, the proposed scheme can effectively prevent selfishly actions of relay nodes in the cooperative NOMA network. Especially, base stations can pay incentives to relay nodes as much as the contributes of relay nodes. Therefore, the proposed scheme can control the selfish behavior of relay nodes to improve the overall system performance.