• ETRI Journal
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• v.43 no.3
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• pp.436-446
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• 2021

In this paper, we propose an energy-efficient unmanned aerial vehicle (UAV) relaying network. In this network, the channels between UAVs and ground transceivers are model-free. A UAV acting as a flying relay explores better channels to assist in efficient data delivery between two ground nodes. The full-duplex relaying mode is applied for potential energy efficiency (EE) improvements. With the genetic algorithm, we manage to optimize the UAV trajectory for any arbitrary radio map scenario. Numerical results demonstrate that compared to other schemes (eg, fixed trajectory/speed policies), the proposed algorithm performs better in terms of EE. Additionally, the impact of self-interference on average EE is also investigated.

• International Journal of Computer Science & Network Security
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• v.22 no.5
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• pp.193-203
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• 2022

After the everyday use of systems and applications of artificial intelligence in our world. Consequently, machine learning technologies have become characterized by exceptional capabilities and unique and distinguished performance in many areas. However, these applications and systems are vulnerable to adversaries who can be a reason to confer the wrong classification by introducing distorted samples. Precisely, it has been perceived that adversarial examples designed throughout the training and test phases can include industrious Ruin the performance of the machine learning. This paper provides a comprehensive review of the recent research on adversarial machine learning. It's also worth noting that the paper only examines recent techniques that were released between 2018 and 2021. The diverse systems models have been investigated and discussed regarding the type of attacks, and some possible security suggestions for these attacks to highlight the risks of adversarial machine learning.

• Asia pacific journal of information systems
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• v.32 no.3
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• pp.630-655
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• 2022

This paper examines the integrated QR code payment service (QRIS) adoption by retailers in Indonesia. Indonesia started its cashless journey in 2017 by using electric money in card form. As the country keeps developing, Indonesia has planned to integrate its payment towards a cross-border payment using QR codes by 2025 in the South East Asian region. Facing government vision, MSMEs that act as the significant economy wheel in Indonesia was required to be prepared to face the multi-cultural, multi-currency, and the new tech innovation for doing transactions. However, as a developing country, Indonesia faced significant problems with its infrastructure, which made it hard for merchants to access digital payment. As infrastructure was a common problem for developing countries, Indonesia also faced financial inclusion, lack of digital knowledge, a high amount of cash use, and socialization that made low digital payment penetration. Therefore, as there was a need to increase digital payment penetration for ASEAN integrated payment, this study found that merchant compatibility, facilitating conditions, trust, and relative advantages are drivers for MSMEs using this payment method. Further, this research provides propositions for banks, financial institutions, and governments to develop and evolve towards a cashless ecosystem, especially for a country lacking infrastructure.

• The Journal of Information Systems
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• v.33 no.3
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• pp.75-104
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• 2024

Purpose The purpose of this study is to analyze the influence of individual characteristics and household environmental factors on OTT consumption, based on the uses and gratifications theory and family systems theory. It seeks to provide strategic and policy insights by incorporating key user attributes and environmental determinants affecting OTT consumption. Design/methodology/approach This research employs multilevel analysis utilizing data from the 2023 Media Panel Survey. The analysis incorporates multilevel data, combining individual and household levels. The Media Panel data, provided by the Korea Information Society Development Institute, encompasses information on households and their members aged six and above. Findings The findings indicate that individual OTT consumption significantly varies based on household environment. Residents of larger cities demonstrated higher OTT expenditure, whereas those in smaller cities exhibited greater OTT usage. A positive correlation was found between the number of OTT services used within a household and individual OTT usage. Interaction effects revealed that residents of smaller cities concentrated more on specific OTT types such as AVOD and AVOD+SVOD,AVOD+SVOD, leading to higher expenditures. While AVOD preference generally resulted in lower OTT expenditure, it increased with higher household OTT service usage. These results underscore the importance of considering both individual preferences and household environments in comprehending OTT consumption, providing a basis for developing customized media policies and content strategies.

• Journal of the Korean Society for Library and Information Science
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• v.17
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• pp.49-83
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• 1989

A Full text retrieval system is a natural language document retrieval system in which the full text of all documents in a collection is stored on a computer so that every word in every sentence of every document can be located by the machine. This kind of IR System is recently becoming rapidly available online in the field of legal, newspaper, journal and reference book indexing. Increased research interest has been in this field. In this paper, research on full text databases and retrieval systems are reviewed, directions for research in this field are speculated, questions in the field that need answering are considered, and variables affecting online full text retrieval and various role that variables play in a research study are described. Two obvious research questions in full text retrieval have been how full text retrieval performs and how to improve the retrieval performance of full text databases. Research to improve the retrieval performance has been incorporated with ranking or weighting algorithms based on word occurrences, combined menu-driven and query-driven systems, and improvement of computer architectures and record structure for databases. Recent increase in the number of full text databases with various sizes, forms and subject matters, and recent development in computer architecture artificial intelligence, and videodisc technology promise new direction of its research and scholarly growth. Studies on the interrelationship between every elements of the full text retrieval situation and the relationship between each elements and retrieval performance may give a professional view in theory and practice of full text retrieval.

• Journal of Broadcast Engineering
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• v.22 no.6
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• pp.755-764
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• 2017

In this paper, we design transmitter and receiver structures for a $2{\times}2$ multiple-input multiple-output (MIMO) in ATSC 3.0 systems and analyze the performance of the $2{\times}2$ MIMO system. In the ATSC 3.0 MIMO systems, spatial diversity and multiplexing gains can be obtained using the spatial demultiplexer and precoder. In this paper, we present the structures of the transmitter and receiver for ATSC 3.0 MIMO systems. Also, we present performance results of the $2{\times}2$ MIMO system through computer simulations.

• Smart Structures and Systems
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• v.7 no.3
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• pp.229-240
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• 2011

Recent developments in Smart Structures with very large scale embedded sensors and actuators have introduced new challenges in terms of data processing and sensor fusion. These smart structures are dynamically classified as a large-scale system with thousands of sensors and actuators that form the musculoskeletal of the structure, analogous to human body. In order to develop structural health monitoring and diagnostics with data provided by thousands of sensors, new sensor informatics has to be developed. The focus of our on-going research is to develop techniques and algorithms that would utilize this musculoskeletal system effectively; thus creating the intelligence for such a large-scale autonomous structure. To achieve this level of intelligence, three major research tasks are being conducted: development of a Bio-Inspired data analysis and information extraction from thousands of sensors; development of an analytical technique for Optimal Sensory System using Structural Observability; and creation of a bio-inspired decision-making and control system. This paper is focused on the results of our effort on the first task, namely development of a Neuro-Morphic Engineering approach, using a neuro-symbolic data manipulation, inspired by the understanding of human information processing architecture, for sensor fusion and structural diagnostics.

• ETRI Journal
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• v.36 no.5
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• pp.741-751
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• 2014

Smart TV is expected to bring cloud services based on virtualization technologies to the home environment with hardware and software support. Although most physical resources can be shared among virtual machines (VMs) using a time sharing approach, allocating the proper amount of memory to VMs is still challenging. In this paper, we propose a novel mechanism to dynamically balance the memory allocation among VMs in virtualized Smart TV systems. In contrast to previous studies, where a virtual machine monitor (VMM) is solely responsible for estimating the working set size, our mechanism is symbiotic. Each VM periodically reports its memory usage pattern to the VMM. The VMM then predicts the future memory demand of each VM and rebalances the memory allocation among the VMs when necessary. Experimental results show that our mechanism improves performance by up to 18.28 times and reduces expensive memory swapping by up to 99.73% with negligible overheads (0.05% on average).

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.4
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• pp.1611-1629
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• 2016

Recently, deploying WiFi access points (APs) for facilitating indoor localization has attracted increasing attention. However, most existing mechanisms in this aspect are typically simulation based and further they did not consider how to jointly utilize pre-existing APs in target environment and newly deployed APs for achieving high localization performance. In this paper, we propose a measurement-based AP deployment mechanism (MAPD) for placing APs in target indoor environment for assisting fingerprint based indoor localization. In the mechanism design, MAPD takes full consideration of pre-existing APs to assist the selection of good candidate positions for deploying new APs. For this purpose, we first choose a number of candidate positions with low location accuracy on a radio map calibrated using the pre-existing APs and then use over-deployment and on-site measurement to determine the actual positions for AP deployment. MAPD uses minimal mean location error and progressive greedy search for actual AP position selection. Experimental results demonstrate that MAPD can largely reduce the localization error as compared with existing work.

• The Journal of Asian Finance, Economics and Business
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• v.5 no.1
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• pp.29-41
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• 2018

These days, corporate risk management has become a major concern in the corporate world. Companies in the global environment are exposed to diverse kinds of risks that are affecting the decisions of investors and other stakeholders. Therefore, companies are expected to not only identify and manage risks but also voluntarily report the same to the stakeholders. Increasingly, standard setters and regulators are requiring firms to disclose such information. On the contrary, there also exists a perception that risk reporting can create a negative impression among the stakeholders about the future of the company. In line with such growing dilemma for risk disclosures, the issue of corporate risk reporting (CRR) has been receiving immense emphasis from the accounting academicians. The main objective of this article is to conduct a comprehensive literature review on corporate risk disclosures. In order to fulfill this objective, at first, a summary of the relevant available literature is presented to identify the current regulations on risk reporting, existing trends of CRR research and theories applied in research. Then, through analysis, several research avenues are identified. It is expected that if these dimensions are explored by the future researchers, a better and broader understanding of the risk reporting practices can be achieved.