• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.2A
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• pp.188-194
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• 2007

In order to become ubiquitous world, the compatibility of wireless machines has become the significant characteristic of a communication terminal. Thus, SDR is the most necessary technology and standard. However, among the environment which has different communication protocol, it's difficult to make a terminal with only hardware using ASIC or SoC. This paper suggests the processor that can accelerate several communication protocol. It can be connected with main-processor, and it is specialized PHY layer of network The C-program that is modeled with the wireless protocol IEEE802.11a and IEEE802.11b which are based on widely used modulation way; OFDM and CDM is compiled with ARM cross compiler and done simulation and profiling with Simplescalar-Arm version. The result of profiling, most operations were Viterbi operations and complex floating point operations. According to this result we suggested a co-processor which can accelerate Viterbi operations and complex floating point operations and added instructions. These instructions are simulated with Simplescalar-Arm version. The result of this simulation, comparing with computing only one ARM core, the operations of Viterbi improved as fast as 4.5 times. And the operations of complex floating point improved as fast as twice. The operations of IEEE802.11a are 3 times faster, and the operations of IEEE802.11b are 1.5 times faster.

• Journal of KIISE:Computing Practices and Letters
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• v.6 no.4
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• pp.421-429
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• 2000

In present, ATM integrated switching system has been developed to a mixed modules that complexed switching system including maintenance, operation based on B-ISDN/LAN service and plug-in module, , which runs on workstation computer system. Meanwhile, workstation has HMI operation system feature including file system management, time management, graphic processing, TMN agent function. The workstation has communicated with between ATM switching module and clients. This computer system architecture has much burden messages communication among processes or processor. These messages communication consume system resources which are socket, message queue, IO device files, regular files, and so on. Therefore, in this paper we proposed new performance modeling with this system architecture. We will analyze the system bottleneck and improve system performance. In addition, in the future, the system has many additional features should be migrated to workstation system, we need previously to evaluate system bottleneck and redesign it. In performance model, we use queueing network model and the simulation package is used PDQ and C-program.

• Journal of Internet Computing and Services
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• v.21 no.4
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• pp.97-107
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• 2020

This study aims to conduct a comprehensive meta-study from the perspective of content analysis to explore trends in Korean academic research on the sharing economy by using the big data analytics. Comprehensive meta-analysis methodology can examine the entire set of research results historically and wholly to illuminate the tendency or properties of the overall research trend. Academic research related to the sharing economy first appeared in the year in which Professor Lawrence Lessig introduced the concept of the sharing economy to the world in 2008, but research began in earnest in 2013. In particular, between 2006 and 2008, research improved dramatically. In order to grasp the overall flow of domestic academic research of trends, 8 years of papers from 2013 to the present have been selected as target analysis papers, focusing on titles, keywords, and abstracts using database of electronic journals. Big data analysis was performed in the order of cleaning, analysis, and visualization of the collected data to derive research trends and insights by year and type of literature. We used Python3.7 and Textom analysis tools for data preprocessing, text mining, and metrics frequency analysis for key word extraction, and N-gram chart, centrality and social network analysis and CONCOR clustering visualization based on UCINET6/NetDraw, Textom program, the keywords clustered into 8 groups were used to derive the typologies of each research trend. The outcomes of this study will provide useful theoretical insights and guideline to future studies.

• Korean Journal of Construction Engineering and Management
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• v.10 no.4
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• pp.50-57
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• 2009

The Korea Standard of Estimate which has been used as the only basis of Cost estimate of public construction projects is failed to reflect the fluctuation of current construction cost. Therefore, the government decided to gradually introduce historical construction cost into cost estimate of public construction projects from 2004 and to reduce the use of Korean Standard of Estimate. This paper presents a series of process and the methodology for computing Actual Cost and analyzing the fluctuation patterns based on not only previous contract prices which made a successful bid but also all of the other bid prices. Also, this paper mainly handles a device for extracting strategic bid price such as low price bid for assuring reliable data and for predicting the construction cost which is built by Wavelet Analysis of Time series Analysis data and Neural Network. It is anticipated that the effective use of the proposed process for estimating actual unit cost would make the cost estimation more current and reasonable.

• Journal of Internet Computing and Services
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• v.17 no.4
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• pp.11-17
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• 2016

In this paper, we proposed a multi-viewer system with multiple HD cameras based AVB(Audio Video Bridge) ethernet cable using IP networking, and FPGA(Xilinx Zynq 702) for bus safety systems. This AVB (IEEE802.1BA) system can be designed for the low latency based on FPGA, and transmit real-time with HD video and audio signals in a vehicle network. The proposed multi-viewer platform can multiplex H.264 video signals from 4 wide-angle HD cameras with existed ethernet 1Gbps. and 2-wire 100Mbps cables. The design of Zynq 702 based low latency to H.264 AVC CODEC was proposed for the minimization of time-delay in the HD video transmission of car area network, too. And the performance of PSNR(Peak Signal-to-noise-ratio) was analyzed with the reference model JM for encoding and decoding results in H.264 AVC CODEC. These PSNR values can be confirmed according the theoretical and HW result from the signal of H.264 AVC CODEC based on Zynq 702 the multi-viewer with multiple cameras. As a result, proposed AVB multi-viewer platform with multiple cameras can be used for the surveillance of audio and video around a bus for the safety due to the low latency of H.264 AVC CODEC design.

• Journal of Internet Computing and Services
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• v.11 no.6
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• pp.13-20
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• 2010

This paper presents a measure to classify healthy persons and Parkinson disease patients from the foot pressure of healthy persons and that of Parkinson disease patients using gait analysis based characteristics extraction and Neural Network with Weighted Fuzzy Membership Functions (NEWFM). To extract the inputs to be used in NEWFM, in the first step, the foot pressure data provided by the PhysioBank and changes in foot pressure over time were used to extract four characteristics respectively. In the second step, wavelet coefficients were extracted from the eight characteristics extracted from the previous stage using the wavelet transform (WT). In the final step, 40 inputs were extracted from the extracted wavelet coefficients using statistical methods including the frequency distribution of signals and the amount of variability in the frequency distribution. NEWFM showed high accuracy in the case of the characteristics obtained using differences between the left foot pressure and the right food pressure and in the case of the characteristics obtained using differences in changes in foot pressure over time when healthy persons and Parkinson disease patients were classified by extracting eight characteristics from foot pressure data. Based on these results, the fact that differences between the left and right foot pressures of Parkinson disease patients who show a characteristic of dragging their feet in gaits were relatively smaller than those of healthy persons could be identified through this experiment.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.4
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• pp.65-73
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• 2008

Due to the amendment of the Act for Urban Parks in 2005, local governments have to establish long-range plans for securing and managing urban parks and green areas. This study aims to propose a method of setting priorities for green areas of land to be preserved before the development stage through the introduction of the concept of Green Infrastructure Assessment, and provide basic data to establish the network of urban parks and green areas by applying the GIA method to the city of Daejeon. The concept of GIA and the process of analysis have been drawn as a result of literature research and case studies. The results of this study show that an introduction of the GIA concept to set park and open space planning promotes the connection of the city planning process as well as presents very a reasonable source to facilitate sustainable development. Also, other results present a priority ranking for protection of parks and green areas as well as a means to manage potential focus areas. This study, does have research limitations such as a limited study area, scale, and conflicts between domestic and foreign computing data. Further studies need to set the planning process and examine the index survey to apply this method to various situations and areas.

• Journal of KIISE:Computing Practices and Letters
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• v.10 no.1
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• pp.99-113
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• 2004

A new architecture called SAN(Storage Area Network) was developed in response to the requirements of high availability of data, scalable growth, and system performance. In order to use SAN more efficiently, most of SAN operating softwares support storage virtualization concepts that allow users to view physical storage devices attached to SAN as a large volume virtually h logical volume manager plays a key role in storage virtualization. It realizes the storage virtualization by mapping logical addresses to physical addresses. A logical volume manager also supports a snapshot that preserves a volume image at certain time and on-line reorganization to allow users to add/remove storage devices to/from SAN even while the system is running. To support the snapshot and the on-line reorganization, most logical volume managers have used table based mapping methods. However, it is very difficult to manage mapping table because the mapping table is large in proportion to a storage capacity. In this paper, we design and implement an efficient and flexible hybrid mapping method based on mathematical equations. The mapping method in this paper supports a snapshot and on-line reorganization. The proposed snapshot and on-line reorganization are performed on the reserved area which is separated from data area of a volume. Due to this strategy normal I/O operations are not affected by snapshot and reorganization. Finally, we show the superiority of our proposed mapping method through various experiments.

• Journal of Internet Computing and Services
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• v.12 no.3
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• pp.27-36
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• 2011

The sensor nodes of sensor network system are capable of wireless communication with sink nodes. They also acquire and transmit sensor data in broad region where people cannot access easily. However, the transmission of redundant data from sensor nodes reduces the lifetime of the entire system and substantial amount of resulted data needs to be resorted before implementing them to the specific applications. In this paper, the mobile agent middleware to eliminate the redundant sensor data is designed and implemented. In the proposed system, the mobile agent visits the destination sensor nodes according to the migration list offered by the meta table in the name space of the naming agent, eliminates the redundant sensor data corresponding to user condition, and acquires and transmits sensor data according to the purpose and needs. Thus, the excess transmission of the sensor data is avoided and the lifetime of the entire system can be extended. Moreover, the experiments using the mobile agent middleware with the conditions and limitations that are possible in real situation ore done to verify the successful elimination of the redundant sensor data and the efficiency of the data acquisition. Also, we show the potential applicability of the mobile agent middleware in various active sensor networks through the active rule based mobile agent middleware or the interaction with the active rule system.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.9
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• pp.864-875
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• 2008

The advent of the ubiquitous environments, the sub-networks is various to offer ubiquitous environments. There are diversify sub-networks such as Jini, UPnP, DPWS. To realize ubiquitous, any users can discovery and services in any sub-networks. However, they cannot support these requirement, because they don't do interoperability with other networks. In this paper, we introduce a Jini adaptor of WSUN(Web Services on Universal Networks). The WSUN is the framework which supports interoperability through the intermediation of Web services. The Jini adaptor has there roles: Lookup Service, Jini Client, Web Service Client. It converts Jini services to Web services and registers them. to UDDI registry. In addition the Jini adaptor process the events which happening in Jini system then that is utilized when another sub-network client search a service. Because the adaptor updates a service status continuously, it is possible that provides a service discovery and use to apply the status information. In conclusion, a Jini client is able to find and use a service which exists in heterogeneous sub-network through the Jini adaptor.