• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.4
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• pp.1223-1236
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• 2014

With the extension of wireless technology, vehicular ad hoc networks provide important services for the dissemination of general data and emergency warnings. However, since, the vehicle topology frequently changes from a dense to a sparse network depending on the speed of the moving vehicles and the time of day, vehicular ad hoc networks require a protocol that can facilitate the efficient and reliable dissemination of emergency messages in a highly mobile environment under dense or intermittent vehicular connectivity. Therefore, this paper proposes a new vehicular broadcast protocol, called BL-CAST, that can operate effectively in both dense and sparse network scenarios. As a low overhead multi-hop broadcast protocol, BL-CAST does not rely on the periodic exchange of beacons for updating location information. Instead, the location information of a vehicle is included in a broadcast message to identify the last rebroadcasting vehicle in an intermittently connected network. Simulation results show that BL-CAST outperforms the DV-CAST protocol in terms of the end-to-end delay, message delivery ratio and network overhead.

• Proceedings of the Korean Society of Computer Information Conference
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• 2015.07a
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• pp.71-72
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• 2015

WSN의 센서 노드는 제한된 자원으로 인해 보안상의 취약성을 가지며 공격자는 쉽게 임의의 데이터를 삽입하는 허위 데이터 주입 공격을 할 수 있다. WSN에서는 이러한 공격이 치명적이기 때문에 허위 데이터를 가능한 빨리 여과해야 한다. 허위 데이터 주입 공격을 탐지하는 기법으로 동적 여과 기법이 제안되었는데 이 기법은 초기 분배된 비밀키에 대한 재분배가 이루어지지 않아 같은 공격에 계속 노출될 경우 불필요한 에너지 소모가 발생한다. 본 논문에서 제안하는 기법은 효율적인 키 재분배를 통해 허위 데이터를 빨리 감지하고 에너지 효율성을 향상시킨다. 전달 노드에서 허위 데이터가 탐지되면 정의된 알람 메시지를 통해 베이스 스테이션에 보고되고 키 재분배를 수행하여 더 효율적으로 허위 데이터를 감지한다. 그러므로 제안 기법은 기존 기법과 비교하였을 때 허위 데이터를 조기에 감지하고 전체 네트워크의 에너지를 절약한다.

• Asia Marketing Journal
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• v.22 no.3
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• pp.51-69
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• 2020

This study empirically examines the link between marketing knowledge management and innovation performance focusing on the moderating role of business environmental volatility. We define marketing knowledge management as the integration of knowledge generation, knowledge dissemination and knowledge storage. Using a unique data set that consists of 439 employees at 156 firms in China, we find that knowledge dissemination and knowledge storage have a positive effect on innovation performance. Also found is the negative moderating effect of business environmental volatility on innovation performance. Our findings suggest that firms should strengthen their marketing knowledge management to improve innovation performance and stay flexible to cope with the ever-changing and often volatile market environments.

• Journal of KIISE:Databases
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• v.33 no.3
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• pp.327-341
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• 2006

As we are getting to deal with more applications that generate streaming data such as sensor network, monitoring, and SDI (selective dissemination of information), active research is being conducted to support efficient processing of queries over streaming data. The applications on the Web environment like SDI, among others, require query processing over streaming XML data, and its investigation is very important because XML has been established as the standard for data exchange on the Web. One of the major problems with the previous systems that support query processing over streaming XML data is that they cannot deal adaptively with dynamically changing stream because they rely on static query plans. On the other hand, the stream query processing systems based on relational data model have achieved adaptiveness in query processing due to query operator routing. In this paper, we propose a system of adaptive query processing over streaming XML data in which the model of adaptive query processing over streaming relational data is applied. We compare our system with YFiiter, one of the representative systems that provide XML stream query processing capability, to show efficiency of our system.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.8
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• pp.53-60
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• 2010

This paper proposes an efficient path maintaining scheme in the grid based wireless sensor networks. The proposed scheme provides the shortest path from a source node to a mobile sink node in a re-established dissemination path. The shortest path can save energy consumption to deliver data to the destination. The proposed scheme can also reduce the cost for path maintenance by reusing the existing path. The simulation results show that the proposed scheme reduces the path maintenance cost by 60% compared to the conventional schemes.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.5
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• pp.482-486
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• 2008

When we design a sensor nodes, a energy-consumption of sensor nodes centers on design concerns to prolong lifetime of sensor network. In recent year, many researches have attempted to study this issue. One of that is TTDD(Two-Tier Data Dissemination approach) proposed to support a sensor network which includes several mobile sensor nodes. But it gives rise to a problem which increasing control packet for the formation and maintenance a grid structure. Therefore, we proposed a Energy-Efficient Routing Protocol used a permanent grid structure for reducing control packets in a sensor network.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.10
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• pp.707-716
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• 2020

The study investigates the relationship between broad-scope management accounting information usage, market orientation, and the firm performance. This study employs a survey data of 149 top-level and mid-level managers working in Vietnamese tourism enterprises. To analyze research data, we employ SmartPLS 3 software. The analytical process include measurement model evaluation (evaluate the scale's validity and reliability) and structural model evaluation (test research hypotheses). The results reveal that broad-scope management accounting information usage has a positive direct effect on market orientation dimensions (include information generation, information dissemination, and responsiveness). Then, market orientation dimensions also have positive direct effects on the performance of Vietnamese tourism firms, excluding information dissemination. Moreover, this study also reveals that the market orientation dimensions mediate the relationship between broad-scope management accounting information usage and firm performance. The findings of this study suggest that tourism firms should pay more attention to the use of management accounting information in decision-making. With the increasingly fierce competition of the tourism firms today, capturing and meeting the needs of the market is a prerequisite to help firms enhance their competitiveness and improve their performance. To do that, Vietnamese tourism firms need to consider pursuing market orientation and enhancing broad-scope management accounting information usage.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.25 no.3
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• pp.210-219
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• 2018

Purpose: The purpose of this study was to investigate the effects of emergency setting visitors' knowledge and behavior patterns in relation to prevention of respiratory tract infections. Methods: A descriptive survey was used. The participants were visitors to the emergency service in 'D' general hospital in 'D' city, and the data were collected from July 1 to September 1, 2016. The collected data were analyzed using frequency analysis, t-test, ANOVA, $Scheff{\acute{e}}$ test, Pearson correlation coefficients, and multiple regression analysis. Results: Factors influencing prevention of respiratory tract infections were visitors' education level, methods of dissemination of prevention information, and participants' knowledge with regard to preventive methods. The explanatory power was found to be 35% in the regression model. Conclusion: The findings indicate that visitors' education level, knowledge of infection prevention, and the dissemination of information regarding infection prevention by the hospital play an important role in the prevention of respiratory tract infections in emergency services in the hospital. These results highlight the need for a customized education program for prevention of respiratory tract infections in emergency settings. Programs should take into consideration the educational background of visitors, and provide them with appropriate information regarding infection prevention.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.3
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• pp.1213-1237
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• 2019

Vehicular Ad-hoc Network (VANET) facilities envision future Intelligent Transporting Systems (ITSs) by providing inter-vehicle communication for metrics such as road surveillance, traffic information, and road condition. In recent years, vehicle manufacturers, researchers and academicians have devoted significant attention to vehicular communication technology because of its highly dynamic connectivity and self-organized, decentralized networking characteristics. However, due to VANET's high mobility, dynamic network topology and low communication coverage, dissemination of large data packets (e.g. multimedia content) is challenging. Clustering enhances network performance by maintaining communication link stability, sharing network resources and efficiently using bandwidth among nodes. This paper proposes a mobility-based, multi-hop clustering algorithm, (MBCA) for multimedia content broadcasting over an IEEE 802.11p-LTE-enabled hybrid VANET architecture. The OMNeT++ network simulator and a SUMO traffic generator are used to simulate a network scenario. The simulation results indicate that the proposed clustering algorithm over a hybrid VANET architecture improves the overall network stability and performance, resulting in an overall 20% increased cluster head duration, 20% increased cluster member duration, lower cluster overhead, 15% improved data packet delivery ratio and lower network delay from the referenced schemes [46], [47] and [50] during multimedia content dissemination over VANET.

• Journal of Distribution Science
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• v.20 no.5
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• pp.85-96
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• 2022

Purpose: This study aims to dissemination a new concept based on empirical research on enhancing entrepreneurship intention (EI) in the theory of planned behavior (TPB) through entrepreneurship mindset (EM) and task technology fit (TTF). The TTF is a moderating variable in strengthening the relationship between EM and EI. Research design, data, and methodology: This research design was quantitative research. The respondents were 202 students from Malaysia and Indonesia who had filled out and collected an online questionnaire in Microsoft form. Three hypotheses examined the direct influence and the indirect impact of EM on EI through antecedent variables of TPB, and the effect of TTF as moderating variable to enhance the relationship between EM and EI. The data was analyzed using the WarpPLS version 7.0. Results: The result showed that EM had a significant impact on the students' EI. The interaction of EM and TTF was significantly able to improve EI. Conclusions: The findings contributed new ideas to develop the theoretical framework of the TPB model and were able be utilized by lecturers to consider the integration of EM and TTF in the model. The novelty of this study elaborated the EM and TTF variables as an extended model of the TPB.