• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권11호
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• pp.4028-4049
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• 2014

Attribute-based encryption (ABE) is a promising cryptographic primitive for implementing fine-grained data sharing in cloud computing. However, before ABE can be widely deployed in practical cloud storage systems, a challenging issue with regard to attributes and user revocation has to be addressed. To our knowledge, most of the existing ABE schemes fail to support flexible and direct revocation owing to the burdensome update of attribute secret keys and all the ciphertexts. Aiming at tackling the challenge above, we formalize the notion of ciphertext-policy ABE supporting flexible and direct revocation (FDR-CP-ABE), and present a concrete construction. The proposed scheme supports direct attribute and user revocation. To achieve this goal, we introduce an auxiliary function to determine the ciphertexts involved in revocation events, and then only update these involved ciphertexts by adopting the technique of broadcast encryption. Furthermore, our construction is proven secure in the standard model. Theoretical analysis and experimental results indicate that FDR-CP-ABE outperforms the previous revocation-related methods.

• 한국데이타베이스학회:학술대회논문집
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• 한국데이타베이스학회 2008년도 연합학회학술대회
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• pp.455-465
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• 2008

최근 방송통신융합에 대한 논의가 활발히 진행되고 있으며, 이미 방송산업과 통신산업의 경계를 무너뜨리는 융합서비스가 시장에서 구현되고 있다. 방송통신융합을 명확히 정의하고 이러한 사회 경제적 흐름에 대비하기 위해서는 무엇보다도 방송통신융합의 미래수요를 기반으로 한 유망 방송통신 융합기술의 발굴 및 개발이 필요하다. 본 논문에서는 방송산업과 통신산업이 모두 '서비스' 중심적인 산업이라는 점을 감안하여 수요자를 중심으로 한 기술개발이 이루어져야 한다는 것에 착안하고, 방송통신융합에 대한 미래수요를 방송통신융합기술에 대한 개발순위를 정하는 선정기준으로 이용함으로써 방송통신융합에 대한 새로운 R&D 프로젝트 선정기준을 제시하고자 한다. 이를 통해, 향후의 방송통신융합 관련 R&D 관리에 새로운 방향을 제시할 수 있을 것으로 기대된다.

• 한국동물위생학회지
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• 제33권2호
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• pp.167-171
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• 2010

Majority of asthma and atopic dermatitis are known to be spontaneously sensitive to house dust mite allergen. Control of house dust mite populations has been principally achieved by using chemical insecticides. But the risk to human health would be a potential problem. Moreover, house dust mite remain as allergens even after death. So, It is more effective method keeping the house dust mites away than killing them. The use of plant-derived repellents has been considered as a promising alternative to chemical repellents. Eucalyptus is a diverse genus of flowering trees in the myrtle family, Myrtaceae. It has insect repellent properties and is an active ingredient in some commercial mosquito repellents. These studies were carried out to investigate repellent effects of Eucalyptus oil against house dust mites and compare lemongrass oil. Eucalyptus oil and lemongrass oil were exposed at different doses (0.2, 0.1, 0.05, 0.025, 0.0125, $0.00625{\mu}l/cm^2$) and different times (1, 3, 6 hours) on house dust mites. The most effective dose of Eucalyptus and lemongrass oils against house dust mites was $0.1{\mu}l/cm^2$ and $0.025{\mu}l/cm^2$. Each repellent effect(%) in most effective dose was 90.3% (Eucalyptus) and 80.8% (lemongrass).

• 한국정보시스템학회지:정보시스템연구
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• 제29권2호
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• pp.111-130
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• 2020

Purpose SNS (Social Network Service) is one of new promising marketing tools which allow marketer to do two-way communication and social interaction. Three characteristics of SNS marketing including informativeness, interactivity, and playfulness are distinguished from traditional marketing. The purpose of this study is to examine the relationships between three characteristics of SNS marketing, brand image, and purchase intention. Design/methodology/approach The present study proposed a research model integrating SNS marketing characteristics, brand image, and purchase intention represented by structural equation modelling and four hypotheses. A total of 20 questionnaire items for five variables were developed and measured by using five point Likert scale. 199 valid data were collected and used to test four hypotheses using SmartPLS. Findings Three hypotheses that the characteristics of SNS marketing such as informativeness, interactivity, and playfulness have a positive influence on brand image were supported at the significance level of 0.05 and 0.001 respectively. The hypothesis regarding the relationship between brand image and purchase intention was also supported at the significance level of 0.001. Brand image plays a significant mediating role in the relationship between SNS marketing and purchase intention. In particular, the result of research that playfulness of SNS marketing affects brand image significantly suggests a new future research theme regarding spiritual marketing. Implications for academics and practitioners were suggested.

• 한국정보통신학회논문지
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• 제2권1호
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• pp.101-108
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• 1998

최근 들어 인터넷의 고속화 및 실시간 서비스 지원에 대한 요구 사항이 증대되고 있다. 인터넷의 고속화 및 QoS (Quality of Service) 보장을 최적으로 지원하는 서브넷 (Subnet)으로 ATM 망이 유력하다. 본 논문에서는 우선, 이러한 추세를 반영하여 최근 IETF와 ATM Forum을 중심으로 활발히 전개되고 있는 인터넷과 ATM의 통합을 위한 프로토콜 표준화 동향을 분석한다. 이에는 ATM Forum에서 진행 중인 LAN Emulation, MPOA와, IETF에서 작업 중인 IP/ATM, NHRP, RSVP 및 IS/ATM 등이 포함된다. 다음, 향후 인터넷과 ATM이 통합되어가는 발전 방향에 대한 전망을 돕기 위하여 통합의 형태를 고찰하고 통합 방식에 대한 분류를 시도한다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.698-705
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• 2008

Under the rapid change in environment of our society and culture, it is also called for a reform in railway management that has traditionally focused on transportation service. Thus developing a business model to use station buildings as a new source of profit has become a promising core business of railway companies. This study aims to find a way to maximize profits by strategically utilizing station buildings and thereby increasing accessibility to customers and consolidating facilities as a key service point. The subjects of this study include eight station buildings that can represent three types of railway stations including departure stations, junction stations, and metro stations. The researcher conducted an analysis on moving lines for examining user distribution and facility utilization within the selected buildings, a survey for collecting basic information on usage and measuring customer satisfaction of facility in the buildings, and a sight analysis to examine accessibility to the station buildings. On the basis of these analyses, the researcher examined the correlations between convenience, visibility, recognizability and functionality with regard to commerce, amenities, couches, direction boards, etc. within station waiting rooms. On the basis of the above analyses, the researcher provides a scheme to increase profitability in railway operation business and customer benefits of using station buildings by drawing up a plan to improve usage of station buildings and maximize profit-making potential for each category of station buildings.

• The Journal of Asian Finance, Economics and Business
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• 제8권5호
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• pp.1001-1010
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• 2021

The world of tourism is a tangible form of a global business trip, which is very promising because it will be estimated to be a sector capable of driving world economic growth resulting from tourists' ever-increasing movement. Currently, in Indonesia, marketing activities in this sector are an integrated process, where the main target is providing customer satisfaction. Thus, the company's marketing activities are expected to be in accordance with customer expectations. The essential purpose of this study was to analyze the mediating role of the effect of trust and customer value on loyalty. The population of this study was users of the Lentera Wisata service in Semarang City, Indonesia. The sampling used a purposive sampling method, with the criteria of male and female customers and customers who have used the Lentera Wisata Semarang service bureau more than once. The test employed multiple regression analyses and the Sobel test. The test results revealed that trust and customer value positively and significantly affected satisfaction. However, trust did not affect customer loyalty. Meanwhile, customer value and satisfaction significantly and positively influenced loyalty. Additionally, the Sobel test results revealed that satisfaction mediated the effect of trust and customer value on customer loyalty.

• International journal of advanced smart convergence
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• 제10권4호
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• pp.84-97
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• 2021

Digital twins are one of the promising digital technologies used to facilitate digital transformation. Therefore, it needs to continually be developed remain relevant in industry and academia. Consolidation of research is required to create a common understanding of the topic and to ensure that future research is built upon a solid foundation. Based on a bibliometric review and a thematic analysis of 217 publications on digital twins from the past two decades, this paper creates and analyzes a visual knowledge map and proposes areas for further research. To comprehensively analyze the development trends and research trends of digital twins, we performed statistical analysis of the relevant literature on digital twins within the core collection database of Web of Science. Through our research, we have shown that the current situation, trends, and hotspots of digital twin research were analyzed via CiteSpace. This study demonstrates that research on digital twins is rapidly growing in popularity, that the output of the research depends largely on the core group of authors conducting it, and that digital twins warrant cross-domain and cross-disciplinary research pathways.

• International Journal of Computer Science & Network Security
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• 제21권3호
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• pp.229-234
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• 2021

The explosive growth of video-based services is considered as the dominant contributor to Internet traffic. Hence it is very important for video service providers to meet the quality expectations of end-users. In the past, the Quality of Service (QoS) was the key performance of networks but it considers only the network performances (e.g., bandwidth, delay, packet loss rate) which fail to give an indication of the satisfaction of users. Therefore, Quality of Experience (QoE) may allow content servers to be smarter and more efficient. This work is motivated by the inherent relationship between the QoE and the QoS. We present a no-reference (NR) prediction model based on Deep Neural Network (DNN) to predict video QoE. The DNN-based model shows a high correlation between the objective QoE measurement and QoE prediction. The performance of the proposed model was also evaluated and compared with other types of neural network architectures, and three known machine learning methodologies, the performance comparison shows that the proposed model appears as a promising way to solve the problems.

• 인터넷정보학회논문지
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• 제23권5호
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• pp.17-23
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• 2022

Network slicing is a promising paradigm and significant evolution for adjusting the heterogeneous services based on different requirements by placing dynamic virtual network functions (VNF) forwarding graph (VNFFG) and orchestrating service function chaining (SFC) based on criticalities of Quality of Service (QoS) classes. In system architecture, software-defined networks (SDN), network functions virtualization (NFV), and edge computing are used to provide resourceful data view, configurable virtual resources, and control interfaces for developing the modified deep reinforcement learning agent (MDRL-A). In this paper, task requests, tolerable delays, and required resources are differentiated for input state observations to identify the non-critical/critical classes, since each user equipment can execute different QoS application services. We design intelligent slicing for handing the cross-domain resource with MDRL-A in solving network problems and eliminating resource usage. The agent interacts with controllers and orchestrators to manage the flow rule installation and physical resource allocation in NFV infrastructure (NFVI) with the proposed formulation of completion time and criticality criteria. Simulation is conducted in SDN/NFV environment and capturing the QoS performances between conventional and MDRL-A approaches.