• Journal of information and communication convergence engineering
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• 제7권2호
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• pp.209-214
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• 2009

The employment of the induction generator is preferable in the natural energy utilization by the minimum maintenance and the mechanical robustness, Another merit is also expected when it is connected to the power network system, because constant-voltage and constant frequency (CVCF) power generation is easily realized in spite of the variation of the rotor speed. However the induction generator needs much amount of the reactive power that reduces power factor in the primary side. The improvement of power factor in the primary side requires large VAR compensator, this point is solved, the merit of the induction machine as a main generator will become more established. This paper proposes a novel approach where the secondary is controlled by a PWM inverter not only to get CVCF power but also to improve the primary power factor. Basically the inverter is controlled so that the field current is supplied from the secondary side in this approach. The required capacity of the inverter is small, because only the slip power is controlled in the secondary side. In the experimental system where the sea wave torque simulator is used, the power factor is well improved by the microcomputer controlled PWM inverter.

• 전자공학회논문지
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• 제49권12호
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• pp.20-26
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• 2012

인지 기반 융합 중첩 네트워크 환경 하에서의 시스템의 성능이 중요한 이슈로 떠오르는 가운데 단말기의 기능성이 좋아짐에 따라 스마트한 지능을 기반으로 접속 자원의 효과적 활용에 적합한 개별 이종 네트워크의 특성분석과 특성을 반영하는 시스템 측면의 접속 최적화가 매우 중요하다고 할 수 있다. 본 논문에서는 기지국의 소형화와 다집적화, 가상화, 지능화가 진행되는 가운데 기지국 hotelling과 같은 기지국 집중화를 통한 통합적 최적화가 가능하므로 이에 대응한 이중 가상 셀 시스템의 특성에 대해 살펴보고 활용도 측면의 성능을 분석하고 향후 다뤄져야 할 사항들을 확인하였다.

• Journal of Computing Science and Engineering
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• 제12권1호
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• pp.12-23
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• 2018

The Internet of Things (IoT) ecosystem potentially includes heterogeneous devices with different processing mechanisms as well as very complicated network and communication models. Thus, analysis of data associated with adverse conditions is much more complicated. Moreover, mobile things in the IoT lead to dynamic alteration of environments and developments of a dynamic and ultra-large-scale (ULS) environment. Also, IoT and the services provided by that are mostly based on devices with limited resources or things that may not be capable of hosting conventional controls. Finally, the dynamic and heterogeneous and ULS environment of the IoT will lead to the emergence of new security requirements. The conventional preventive and diagnostic security controls cannot sufficiently protect it against increasing complication of threats. The counteractions provided by these methods are mostly dependent on insufficient static data that cannot sufficiently protect systems against sophisticated and dynamically evolved attacks. Accordingly, this paper investigates the current security approaches employed in the IoT architectures. Moreover, we define the dynamic security based on dynamic event analysis, dynamic engineering of new security requirements, context awareness and adaptability, clarify the need for employment of new security mechanism, and delineate further works that need to be conducted to achieve a secure IoT.

• 지역사회간호학회지
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• 제15권4호
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• pp.566-576
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• 2004

Purpose: The study was to determine variables related to the depressive impact of emotional labor among workers. Method: 443 respondents were surveyed through the NIOSH generic job stress questionnaire from December 1st through December 30th, 1999. Results: 1. Employment type and job insecurity showed a significant relationship with developing depression, load and role ambiguity. 5. Intervention programs and effective communication networks are needed to help workers cope with their job stress in a positive manner. Conclusions: First, given the correlation between the frequency of avoiding tactics and depression levels, an intervention program is needed to help workers cope with their job stress in a positive manner, Lastly, because role ambiguity was one of the main causes of depression among workers who perform emotional labor, establishing an effective communication network is important to make communication flow within the workplace clear and open.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2019년도 춘계학술대회
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• pp.15-17
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• 2019

학교 행사나 취업정보, 진학정보, 주요학사일정 등 중요한 정보를 현재는 가정통신문만을 통하여 정보를 전달 받기 때문에 일부 정보의 사각지대가 발생하고 있었다. 이러한 문제를 해결하기 위해 사물인터넷 기반 스마트 교육에 대한 자료조사를 바탕으로 유무선 네트워크에서 P2P방식의 사물인터넷 기술을 접목 전자보드 프로토타입을 설계하였다. 각 교실에서 학교 행사 등 필요한 정보를 교무실에서 실시간으로 자료를 받아 교실에서 공유 받을 수 있도록 하였다. 또한 전자보드 사용 방법을 잘 알지 못해도 누구나 손쉽게 이용할 수 있기 때문에 사물인터넷 기반 스마트교육용 전자보드 프로토타입을 설계 하고자 한다.

• International Journal of Internet, Broadcasting and Communication
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• 제13권1호
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• pp.37-46
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• 2021

Recently, social technologies have been created to solve problems from businesses for the establishment of generational solidarity ecosystem in terms of employment, residential space, network and social capital, age, cognitive and environmental aspects. This is senior-friendly healthcare business system aimed at meeting the senior needs for health life to enjoy active consumption culture life even after retirement, becoming a catalyst for minimizing generational conflicts, preventing the cognitive and physical deterioration of seniority in the areas of life healthcare, fitness and well-aging, and expanding into systems necessary for seniority self-reliance. We would like to draw up the development and requirements of the concept of the service platform for the study of collective characteristics for generation solidarity with senior class and the establishment of a customized senior health life system for generation solidarity. This system is characterized by a platform that can prevent the decline of seniors' cognitive and physical functions and enhance emotional stability. It is significant in providing feedback on the risk perception index, fall index, and prevention training index information to the child through the analysis and extraction of the senior health index for risk perception, fall probability, and fall prevention.

• 한국치위생학회지
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• 제23권1호
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• pp.63-72
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• 2023

Objectives: This study aimed to identify the level of occupational and organizational retention intention and related factors among new dental hygienists. Methods: The participants were 195 dental hygienists employed for less than 24 months. A t-test and one-way analysis of variance were conducted to determine the level of intention to stay according to an individual's major-related characteristics and work environment awareness level. Pearson's correlation analysis was performed for each item, and stepwise multiple regression was performed for factors related to retention intention. Results: In the work environment, the organizational support network had the highest occupational retention intention (β=0.513). Organizational retention intention (β=0.351), working infrastructure (β=0.293), cooperation relationship (β=0.165), and management justice (β=0.151) were factors related to organizational retention intention (p<0.001). Employment at the practice hospital was related to occupational (β=0.167) and organizational retention intention (β=0.138), and satisfaction with clinical practice was related to occupational retention intention (β=0.327). Conclusions: New dental hygienists are expected to be actively utilized for long-term tenure in both occupations and organizations by actively reflecting on the results obtained through this study in the curriculum and working environment of dental hygienists.

• 4차산업연구
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• 제2권1호
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• pp.33-43
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• 2022

Purpose - With the rapid development of information technology, the digital economy has become an important grip of the new development pattern, and the digital transformation of enterprises is a major trend. As SMEs are the mainstay of the economy and employment, it is important to study the digital transformation of SMEs to promote the development of the digital economy. Research design, data, and methodology - Based on a resource-based view, this report analyses the current situation and issues of digital transformation of SMEs from the perspective of digital orientation as well as the breadth and depth of technological capabilities of enterprises, using data from a survey of 200 manufacturing enterprises in China. Result - The results show that SMEs generally have a digital transformation mindset, but a weak digital foundation. In order to execute a digital strategy, companies need digital transformation capabilities. These behavioral capabilities are guided by the strategic direction of the business, and companies with strong capabilities are always trying to tap into the full digital potential. Conclusion - In order to effectively promote the digital transformation of SMEs, we suggest that SMEs pay attention to digital capability building, make good use of digital platforms and network resources, and lay a solid foundation for digital transformation; meanwhile, we suggest that government departments play a guiding and supporting role to build a cross-industry and cross-sector digital synergy system to help promote the development of SMEs' digital transformation. This paper presents some suggestions from both the internal and external environment of the enterprise, with the expectation of contributing to the digital transformation practices of SMEs.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제17권10호
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• pp.2701-2717
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• 2023

In this paper, a hybrid fuzzy-based method is suggested for determining India's best system for power generation. This suggested approach was created using a fuzzy-based combination of the Giza Pyramids Construction (GPC) and Recalling-Enhanced Recurrent Neural Network (RERNN). GPC is a meta-heuristic algorithm that deals with solutions for many groups of problems, whereas RERNN has selective memory properties. The evaluation of the current load requirements and production profile information system is the main objective of the suggested method. The Central Electricity Authority database, the Indian National Load Dispatch Centre, regional load dispatching centers, and annual reports of India were some of the sources used to compile the data regarding profiles of electricity loads, capacity factors, power plant generation, and transmission limits. The RERNN approach makes advantage of the ability to analyze the ideal power generation from energy data, however the optimization of RERNN factor necessitates the employment of a GPC technique. The proposed method was tested using MATLAB, and the findings indicate that it is effective in terms of accuracy, feasibility, and computing efficiency. The suggested hybrid system outperformed conventional models, achieving the top result of 93% accuracy with a shorter computation time of 6814 seconds.

• 한국산림과학회지
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• 제95권3호
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• pp.235-239
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• 2006

이 연구는 사회연결망분석을 이용한 이해당사자간 관계 구조(relational structure) 분석이 국립공원 관리에 나타난 갈등을 분석하고, 보다 효율적인 갈등해결 방안을 제시하는 연구방법론으로서 타당한지 살펴보고자 하였다. 태안해안 국립공원 이해당사자 12명을 전화면접 설문조사 하여 국립공원 관리를 둘러싼 갈등에 대한 인식과, 갈등발생시 맺는 응답자간 사회연결망 특성을 평상시에 맺는 사회연결망 특성과 비교하여 살펴보았다. 갈등 발생시에는 국립공원관리공단으로부터 정보를 구하지 않는 응답자의 수가 평상시보다 많았고, 갈등 발생시 중요 의사 결정을 할 때 응답자들은 평상시보다 외톨이가 더 많이 나타나 응답자들간 상호교류가 덜 활발하였다. 갈등 해결을 위해 국립공원관리공단은 이해당사자에게 정보를 직접 전달하기보다는 이해당사자들이 선호하는 정보원에게 정보를 배분하고, 외톨이로 분산된 이해당사자가 서로 교류하여 협력적 관계를 형성할 수 있도록 매개자를 찾거나 제3자를 개입하도록 할 필요가 있음을 확인하였다. 따라서, 사회연결망 분석이 국립공원을 둘러싼 갈등관리 연구에 이바지 할 수 있는 연구방법론이라고 볼 수 있으며 향후 보다 다양한 국립공원 갈등 관리 연구에 응용할 필요가 있다.