• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.5A
• /
• pp.417-422
• /
• 2010

In this paper, we propose a new routing scheme based on the multiple layer routing strategy. This algorithm can guarantee the required QoS while maximizing energy efficiency in wireless sensor networks. The principle contributions of this work are its simplicity, scalability and responsiveness to current network situations. Simulation results indicate the superior performance of our proposed algorithm, while other existing scheme cannot offer such an attractive performance balance.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.21 no.11
• /
• pp.2089-2094
• /
• 2017

Altmetrics is the measurement index and quantitative data to complement the traditional indicators based on the citation. Altmetrics research has acquired greater importance in the past few years, partly due to the complement to the traditional bibliometrics. This paper aims to reveal the research status and trends in altmetrics research. A total of 187 articles from 2005 to 2017 are obtained and analyzed, illustrating a steady rise (S-mode) in altmetrics research since 2005. Using social network analysis and co-word analysis, the author cooperation network and keyword co-occurrence network are developed. The core scientists and eight international research groups are discovered, reflecting that researchers in this field have a low degree of cooperation. Four topics of altmetrics research are discovered by hierarchical clustering. The results can be useful for the advanced research of altmetrics.

• Journal of Internet Computing and Services
• /
• v.10 no.2
• /
• pp.153-160
• /
• 2009

One of the major challenges of designing a dissemination protocol for Wireless Sensor Networks(WSNs) is energy efficiency. Recently, this issue has received much attention from the research community, and SPMS, which outperforms the well-known protocol SPIN, specially is a representative protocol. In addition, one of many characters of SPMS is the use of the shortest path to minimize the energy consumption. However, since it repeatedly uses the same path as the shortest path, the maximizing of the network lifetime is impossible, though it reduces the energy consumption. In this paper, we propose a dissemination protocol using probability-based clustering which guarantees energy-efficient data transmission and maximizes network lifetime. The proposed protocol solves the network lifetime problem by a novel probability function, which is related to the residual energy and the transmission radius between nodes. The simulation results show that it guarantees energy-efficient transmission and moreover increases the network lifetime by approximately 78% than that of SPMS.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.11 no.1
• /
• pp.141-150
• /
• 2011

In this paper, we propose a Cross-Layer Cooperative Routing(CLCR) architecture to support transmission efficiency in mobile wireless sensor networks. The main features and contributions of the proposed architecture and method are as follows. First, the clustering which uses the location information of nodes is utilized as infrastructure. Second, a cross-layer strategy which uses the technologies of network layer, MAC layer, physical layer together to support transmission efficiency and channel efficiency for cooperative-aided routing and transmission. Third, we consider realistic approach in the view points of the mobile ad-hoc wireless sensor networks while conventional methods just consider fixed sensor network environments. The performance evaluation of the proposed method is performed via simulation using OPNET and theoretical analysis. The results of performance evaluation of the proposed CLCR show improvement of transmission efficiency by the proposed CLCR.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.42 no.12
• /
• pp.61-70
• /
• 2005

In this paper, we propose an efficient global placement algorithm which is an enhanced version of Hybrid Placer$^{[25]}$, a standard cell placement tool, which uses a middle-down approach. Combining techniques used in the well-known partitioner hMETIS and the RBLS(Relaxation Based Local Search) in Hybrid Placer improves the quality of global placements. Partitioning techniques of hMETIS is applied in a top-down manner and RBLS is used in each level of the top-down hierarchy to improve the global placement. The proposed new approach resolves the problem that Hybrid Placer seriously depends on initial placements and it speeds up without deteriorating the placement quality. Experimental results prove that solutions generated by the proposed method on the MCNC benchmarks are comparable to those by FengShui which is a well known placement tool. Compared to the results of the original Hybrid Placer, new method is 5 times faster on average and shows improvement on bigger circuits.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.17 no.11
• /
• pp.2699-2707
• /
• 2013

We proposed the context-awareness routing algorithm DDV (Dynamic Direction Vector)-hop algorithm at Mobile Ad-hoc Network(MANET). MANET has problem about dynamic topology, the lack of scalability of the network by mobile of node. By mobile of node, energy consumption rate is different. So it is important choosing routing algorithms for the minium of energy consumption rate. DDV-hop algorithms considers of the attribute of mobile node, create a cluster and maintain. And it provides a path by searching a route more energy efficient. We apply mobile of node by direction and time, the alogorighm of routning path and energy efficiency clustering is provided, it is shown the result of enery consumption that is optimized for the network.

• Journal of KIISE:Software and Applications
• /
• v.31 no.9
• /
• pp.1121-1130
• /
• 2004

This paper proposes a method for line and word segmentation for machine-printed text blocks. To separate a text region into the unit of lines, it analyses the horizontal projection profile and performs a recursive projection profile cut method. In the word segmentation, between-word gaps are identified by a hierarchical clustering method after finding gaps in the text line by using a connected component analysis. In addition, a special symbol detection technique is applied to find two types of special symbols tying between words using their morphologic features. An experiment with 84 text regions from English and Korean documents shows that the proposed method achieves 99.92% accuracy of word segmentation, while a commercial OCR software named Armi 6.0 Pro$^{TM}$ has 97.58% accuracy.y.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.23 no.1
• /
• pp.191-201
• /
• 2023

As Edutech arises which is integrating IT technology into education, many related attempts have been tried on music education area. The focus has been shifted from the teachers to the learners, and this makes the personalized learning emerge. The learner's proficiency is an essential factor to support the personalized learning. The chord fingering is an important technique in piano learning. In this paper, a personalized learning tool for piano chords has been suggested. And then, several utilization ways have been described by analyzing the chords patterns. Specifically, the difficulty of the chords and the proficiency of the learner are derived from the accumulated practicing log data of the users. More effective learning way of the chords has been presented through hierarchical clustering based on chords similarity. Furthermore, the suggested approach where only the practicing log data are used lessens the learner's burden to measure the proficiency and the chord's difficulty without additional efforts like taking tests.

• Journal of the Korea Society of Computer and Information
• /
• v.16 no.10
• /
• pp.197-203
• /
• 2011

In this paper, a new cluster configuration process is proposed. The energy consumption of sensor nodes is reduced by configuring the initial setup process only once with keeping the initial cluster. Selecting the highest power consumed node of the member nodes within the cluster to the header of next round can distribute power consumption of all nodes in the cluster evenly. With this proposed way, the lifetime of the USN is increased by the reduced energy consumption of all nodes in the cluster. Also, evenly distributed power consumptions of sensors are designed to improve the energy hole problem. The effectiveness of the proposed algorithms is confirmed through simulations.

• Journal of KIISE:Software and Applications
• /
• v.31 no.10
• /
• pp.1286-1303
• /
• 2004

Component-based Development is gaining a wide acceptance as an economical software development paradigm to develop applications by utilizing reusable software components. Well-defined interface manages coupling and cohesion between components, minimizes the effect on the user in case of component evolvement, and enhances reusability, extendibility and maintainability. Therefore, study on systematic development process and design guidelines for component interface has been required since the component has been introduced. In this paper, we propose three types of interfaces based on software architecture layers and functionality types； Provided Interface which provides functionality of a component, Required Interface which specifies required functionality that is provided by other components, and Customize Interface which tailors the component to customer's requirement. In addition, we suggest design criteria for well-designed interface, and systematic process and instructions for designing interface. We firstly cluster operations extracted from use case model and class model to identify Provided interfaces, and design Customize interfaces based on artifacts for variability. We also specify Required interfaces by identifying dependency among interfaces. Proposed interface design method provides traceability, throughout the component interface design. And furthermore, proposed guidelines support practical design for high quality component based on a case study.