• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.1B
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• pp.9-14
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• 2012

The neighbor discovery using directional antennas in mmWave band is a prerequisite for communications and this issue is crucial and urgent. In this paper, the synchronized, direct, two-way directional neighbor discovery process is analyzed mathematically for mmWave WPANs. The analysis is based on the values which are derived from the effect of using directional antennas. The neighbor discovery probability for a given amount of time is considered and several performance measures such as the optimal sojourn time are derived in closed forms. Numerical results are obtained using parameters based on the IEEE 802.15.3c. The mathematical analysis provides the theoretical basis for the directional neighbor discovery process.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.6
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• pp.17-29
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• 2021

Recently, as social distancing have been raised due to the re-spread of COVID-19, the number of serial entrepreneurs who are closing their business is rapidly increasing. Learning from failure is a source of success, but business failure can result in psychological and economic losses and negative emotions of the serial entrepreneur. At this point, it is very important to find a way to recover the negative emotions caused by business failures of serial entrepreneurs. Recently, a strategic model has emerged to deal with the negative emotions of grief caused by business failures of serial entrepreneurs. This study identified the recovery factors from the grief of business failures of serial entrepreneurs and analyzed Shepherd's(2003) three areas: loss orientation, restoration orientation, and dual process. To this end, individual in-depth interviews were conducted with 12 small business serial entrepreneurs who challenged re-startup to identify the attributes of recovery factors that were not identified with quantitative data. As a result of the study, first, recovery factors were investigated in three areas: individual orientation, family orientation, and network orientation. It was found to help improve recovery in nine categories: self-esteem, persistence, personal competence, hobbies, self-confidence, family support, networks, religion, and social support. Second, recovery obstacle factors were investigated in three areas: psychological, economic, and environmental factors. Nine categories including family, health, social network, business partner, competitor, partner, fund, external environment, and government policy were found to persist negative emotions. Third, the emotional processing process for grief was investigated in three areas: loss orientation, restoration orientation, and dual process. Ten categories such as family, partner support, social member support, government support, hobbies, networks, change of business field, moving, third-party perspective, and meditation were confirmed to enhance rapid recovery in the emotional processing process for grief. The implications of this study are as follows. The process of recovering from the grief caused by business failures of serial entrepreneurs was attempted by a qualitative study. By extending the theory of Shepherd(2003), This study can be applied to help with recovery research. In addition, conceptual models and propositions for future empirical research were presented, which can be discussed in carious academic ways.

• The Magazine of the IEIE
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• v.33 no.2 s.261
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• pp.62-71
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• 2006

SDR 시스템의 구조는 개방상, 분산성, 객체지향성, 소프트웨어 제어성을 제공하는 구조이어야 한다. 이러한 조건을 만족하는 SDR 시스템에 사용된 SDR시스템의 소프트웨어는 단일 하드웨어 플랫폼에서 독립적으로 동작이 가능한 개방성을 확보하는 것이다. 이 방법은 모듈화를 지향하며, 재사용성을 증대시키고, 개발 시에도 많은 유연성을 확보 할 수 있을 뿐만 아니라 시스템을 재구성하여 운용 할 수 있도록 해 준다. 본 논문은 SDR기반 스마트안테나 기지국 시스템에서 SDR 네트워크가 추구하는 개방형, 객체지향성 및 제어성 등을 확보 할 수 있도록 하고 SDR 네트워크와 유연하게 연동 할 수 있도록 기지국 시스템 내의 각 소프트웨어 모듈간의 인터페이스를 정의하였다. 또한, 스마트안테나 기지국의 API(Application Program Interface)를 제시하고 이에 대한 Usecase를 보임으로써 제안하는 스마트안테나 기지국의 API의 활용성을 증대시켰다.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.05a
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• pp.885-888
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• 2008

무선 센서 네트워크 라우팅 프로토콜에서의 경로탐색에서 중복 브로드캐스트 메시지에 의한 비용이 증가되고, 많은 노드들이 동시에 통신을 시도하기 때문에 많은 충돌이 발생한다. 이러한 문제를 해결하기 위해 본 논문에서는 Directed Diffusion 라우팅 방법에 지향성 안테나를 도입하여 채널 이용율을 높여 통신에서의 충돌을 줄이고 네트워크 구성 및 유지 시 사용될 flooding의 범위와 노드간의 통신시 불필요한 방향으로의 통신을 최소화하여 중복되는 브로드캐스트 메시지 수를 줄일 수 있는 라우팅 방법을 제안한다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.4
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• pp.627-635
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• 2008

Using directional antenna in wireless network can offer many advantages including significant decrease of interference, increase of spatial reuse and possibility of improving network capacity. However, existing 802.11 MAC is designed for use of omni-directional antenna then those advantages can not be shown in that MAC protocol when it uses directional antenna. In this paper, we present a MAC protocol specifically designed for directional antenna to achieve spatial reuse and improve capacity of MAC protocol. Simulation result shows the advantages of our proposal in comparison with existing MAC in terms of end-to-end delay and network throughput.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.3
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• pp.121-143
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• 2021

As the social economy emerges as one of the alternatives for solving social problems, interest and experiments on social franchise, a methodology for scaling the social economy, continue to increase. The success or failure of social franchise has a huge impact on franchisors, members of franchisees, as well as beneficiaries, local residents, and stakeholders in the region, but research on ways to increase their chances of success is still insufficient. Based on previous studies, this study tried to derive success factors by analyzing the effects of social franchise characteristics on business performance, and to understand the mediating effect of franchise autonomy, which is the differentiation point of social franchises, between characteristic factors and business performance. Social value orientation, social economy experience, local network utilization, and customer orientation were derived as characteristic factors affecting business performance, and franchise autonomy was set as a mediating variable, and a survey was conducted for franchisee members and their influence was analyzed. Through this study, it was found that social economy experience and local network utilization had a positive (+) effect on economic performance, and social value orientation, local network utilization, and customer orientation had a positive (+) effect on social performance. Also, the results of franchise autonomy playing a mediating role between social economy experience, local network utilization and economic performance, and a mediating role between local network utilization and social performance were presented. This study has significance as the first study to conduct a full-scale empirical study on social franchises. It is hoped that theoretical research on social franchises will be more active in the future and will be used as a useful reference for performance creation for organizations that seek or already operate social franchises.

• Korean small business review
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• v.43 no.3
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• pp.91-117
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• 2021

The purpose of this study is to study the effect of internatioanl entrepreneurial orientation of small and medium-sized Chinese manufacturing companies on export performance. A total of 183 corporate data were used for empirical analysis for Chinese manufacturing export companies. In summary, first, international entrepreneurial orientation was shown to have a significant positive effect on export performance, second, international etrprenurial orientation was shown to have a significant positive effect on absorption capacity, and third, the stronger environmental dynamics and network capacity, the stronger international business orientation and export ability. The implications of this study are summarized as follows. It suggests that the more innovative, enterprising and risk-taking Chinese SMEs are, the better their export performance and the better their ability to absorb foreign knowledge. It also suggests that small business managers must continue to strengthen their network capabilities to improve export performance through international entrepreneurial orientation, and this relationship is further strengthened in a dynamic environment. It also suggests that the impact of firm's absorption capacity on export performance will weaken over time.

• Journal of Korea Society of Industrial Information Systems
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• v.22 no.4
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• pp.79-95
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• 2017

This Study Investigates Whether R&D Capabilities and Market Orientation have Significant Effects on Product Innovation Performance in Order to Enhance Customer Value and Technology Innovation Competitiveness Considering the Characteristics of Rapidly Changing Semiconductor Industry. In other Words, as in the Research Model, the Purpose of this Study is to Investigate the Causal Relationship between the Independent Variable, R&D Capability and Market Orientation, on Product Innovation Performance, which is a Dependent Variable, through the Moderating Variable of Technological Innovation Orientation. For this Study, we Conducted a Questionnaire Survey on the Employees of Development Companies in the Semiconductor Industry and Finally Collected 118 Valid Questionnaires. The Collected Data was Analyzed by Multiple Regression Analysis with Demographic Characteristics as Control Variable and Hierarchical Regression Analysis was Conducted with the Moderating Effects of Technological Innovation Orientation. The Results Showed that the Higher the R&D Intensity and the External Network Capacity, the Higher the Product Innovation Performance. Also, the Product Innovation Performance was Higher than the Customer Orientation and Competitor Orientation Among the Market Orientation. In Addition, only R&D Capability Confirms that Technology Innovation Orientation is Moderated. The Result of this Study is to Improve Understanding of R&D Capability and Market Orientation in Creating of Product Innovation Performance of Semiconductor Companies and to offer Valuable Research Data in Empirically Supporting that Technological Innovation Orientation is an Important Moderating Factor in Creating Firm's Product Innovation Performance and Sustainable Competitive Advantage.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37B no.9
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• pp.778-786
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• 2012

Sensors that are used on wireless sensor networks can be divided into two types: directional sensors, such as PIR, image, and electromagnetic sensors; and non-directional sensors, such as seismic, acoustic and magnetic sensors. In order to guarantee the line-of-sight of a directional sensor, the installation location of the sensor must be higher than ground level. Among non-directional sensors, seismic sensors should be installed on the ground in order to ensure the maximal performance. As a result, seismic sensors may have network connectivity problems due to communication failure. In this paper, we propose a 3D node deployment method to maximize the coverage and the network connectivity considering the sensor-specific properties. The proposed method is for non-directional sensors to be placed on the ground, while the directional sensor is installed above the ground, using trees or poles, to maximize the coverage. As a result, through the topology that the detection data from non-directional sensors are transmitted to the directional sensor, we can maximize the network connectivity. Simulation results show that our strategy improves sensor coverage and network connectivity.

• Journal of Service Research and Studies
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• v.6 no.4
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• pp.15-34
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• 2016

The purpose of this study is to examine the effects of social entrepreneurship on organizational performance and to identify network moderating effects on social entrepreneurship and organizational performance. Data collected from 189 employees working in social enterprises were analyzed by using SPSS 18.0 program. Results are as follows: First, innovativeness, proactiveness, and social value orientation which were sub-factors of social entrepreneurship had positive effects on social performance. Second, proactiveness, risk-taking, and social value orientation which were sub-factors of social entrepreneurship had positive effects on economic performance. Third, the network significantly moderated the effects on innovativeness, proactiveness, social value orientation which were sub-factors of social entrepreneurship, and social performance. Fourth, the network significantly moderated the effects on proactiveness which was a sub-factor of social entrepreneurship, and economic performance. These results exhibited that the social entrepreneurship was effective to increase the organizational performance by activating the network and proposed a useful approach for further studies as an investigation method.