• ETRI Journal
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• v.40 no.5
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• pp.613-623
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• 2018

The instability of operational channels on cognitive radio networks (CRNs), which is due to the stochastic behavior of primary users (PUs), has increased the complexity of the design of the optimal routing criterion (ORC) in CRNs. The exploitation of available opportunities in CRNs, such as the channel diversity, as well as alternative routes provided by the intermediate nodes belonging to routes (internal backup routes) in the route-cost (or weight) determination, complicate the ORC design. In this paper, to cover the channel diversity, the CRN is modeled as a multigraph in which the weight of each edge is determined according to the behavior of PU senders and the protection of PU receivers. Then, an ORC for CRNs, which is referred to as the stability probability of communication between the source node and the destination node (SPC_SD), is proposed. SPC_SD, which is based on the obtained model, internal backup routes, and probability theory, calculates the precise probability of communication stability between the source and destination. The performance evaluation is conducted using simulations, and the results show that the end-to-end performance improved significantly.

• The Journal of Information Systems
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• v.25 no.3
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• pp.31-60
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• 2016

Purpose In 2016, the market size of mobile(m-) shopping goes beyeond more than half of a total of online shopping. People use smartphones as the main device for m-commerce. Under the circmustances, this study attempts to address why people prefer to use smartphone-based m-commerce. In other words, it is necessary to understand the main value that smartphone-based m-commerce creates. Drawing on the studies of consumption value, this study focuses on utilitarian value in predicting customers' continuance intention in the context of smartphone-based m-commerce, recognizing that utilitarian value is a key extrinsic motivation in the goal-oriented, performance-oriented shopping contexts. Furthermore, this study identifies factors affecting customers' utilitarian value from the perspective of benefits and costs, following the notion that it represents the result of evaluating a trade-off of benefits and costs caused by smartphone-based m commerce. More specifically, in this study, ubiquitous service, location-based service (LBS), transaction speed, and price utility belong to the benefit dimension, whereas technology anxiety and cognitive effort belong to the cost dimension. Design/methodology/approach To test the proposed hypotheses, the study conducted partial least squares (PLS) analysis with a total of 294 data collected on users with experience in smartphone-based m-commerce. Findings The results show that first, utilitarian value is increased by the benefits, such as ubiquitous service, transaction speed, and price utility. However, LBS has no direct effect on utilitarian value. Second, the noteworthy finding is that ubiquitous service and LBS greatly increase transaction speed. Third, technology anxiety and cognitive effort considered as the cost dimension are negatively associated with utilitarian value but their impacts on it are non-significant. Finally, the results support the argument that utilitarian value is a determinant of continuance intention. Overall, the findings imply that utilitarian value greatly depends on the peception on benefits rather than the aspect of cost in smartphone-based m-commerce. Overall, the findings offer new insight into the studies of m-commerce by considering and verifying the impacts of its benefits and costs simultaneously.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.237-238
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• 2008

This paper presents a cognitive radio network where a base station exploits multi-antennas. For the system, a joint power control and user selection greedy algorithm which achieve a significant fraction of sum-capacity at lower complexity cost is proposed.

• International Commerce and Information Review
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• v.10 no.4
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• pp.47-62
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• 2008

The purpose of this study is to explore the antecedent factors to the piracy of the digital copyrights in order to provide basic data for piracy prevention policy. The findings of study revealed that most respondents had experiences to copy MP3 files illegally. And many respondents answered they didn't copy pirated material by themselves but others did piracy a lot. The feeling of quilt and anxiety against piracy is shown very low level. Low copy cost and regulation level significantly impact upon the cognitive level of other's piracy. Updated contents, the higher price of authenticated materal, piracy regulation are the significant antecedent factors to the level of piracy. The level of piracy activity and anxiety against piracy are significantly different by age. The cognitive level of other's piracy, piracy activity and anxiety are significantly different by gender.

• Journal of Korean Society for Quality Management
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• v.20 no.2
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• pp.94-108
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• 1992

This study involves an experiment for the cognitive experiment design and the human reliability in software engineering. Its overall objectives are to analyze common-cause human domain error and reliability in human-software interaction. A laboratory study was performed to analyze software engineers' task behavior in software production and to identify software design factors contributing to the effects in common cause failure redundancy. Common-cause model and its function were developed, then the main experiment using programming experts was conducted in order to define a new cognitive paradigm, in the aspects of identification, pattern recognition, and behavior domain for human reliability and quality control in software development. The results and analytical procedures developed in this research can be applied to reliability improvement and cost reduction in software development for many applications. Results are also expected to provide guidelines for software engineering quality control and for more effective design of human-software interface system.

• International Journal of Computer Science & Network Security
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• v.23 no.8
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• pp.33-39
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• 2023

The global surge in depression and anxiety, intensified by challenges such as cost and stigma, emphasizes the pressing need for accessible, evidence-based digital solutions. The research centers on the creation of a mobile application specifically designed to address mental health challenges. By integrating cognitive behavioral therapy techniques and features like appointment bookings and mindfulness feedback tools, the app is positioned to improve user outcomes. Utilizing platforms like React Native and React, combined with NestJS for enhanced backend security, the application adheres to the rigorous standards required for mental health interventions. Collaborative efforts with experts, notably the counseling unit of IIUM, ensure the app's alignment with contemporary best practices and research. Preliminary findings indicate a promising tool with the potential to address the global mental health treatment disparity.

• Journal of Korean Academy of Nursing Administration
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• v.4 no.2
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• pp.351-361
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• 1998

The purpose of this study was to explore whether there is a point within the range of physical impairment after which the cost of home care exceeds the cost of nursing home care among the elderly who require long-term care. The provision of long-term care for the elderly is a major health policy issue, in part due to the aging of the American population and dramatic increase in health care costs. The framework for this study was guided by Pollak's(1973)model of costs of alternative care settings for the elderly. This study used a retrospective, descriptive correlational design. Physical impairment was measured by the modified Index of Activities of Daily Living(Katz et al. 1963). Cost of care was measured by the average cost per patient per day. The sample for this study included 67 patients receiving long-term care at home from the Long-term Home Health Care Programs (LTHHCPs) and 67 patients receiving long-term care in nursing homes. Data were collected on patient characteristics. including activities of daily living and cognitive impairment. and on the number of physician visits. emergency room visits. and hospitalization from the patient records. For each patient. Medicaid cost data for home care services/or nursing home services were collected from the financial department of each home care agency or nursing home. The living costs and informal care costs were estimated for home care patients. The results indicated that the home care sample and the nursing home sample were similar in terms of gender. ethnic background. and marital status. The elderly patients in the home care sample were: however. younger and less physically impaired than those in the nursing home sample. The hypotheses of this study were supported: For elderly persons with physical impairment scores below 12(possible range of 0 to 14), cost of care was lower in home care than in the nursing home care setting. However, for elderly persons with physical impairment scores above 12. the cost of care was higher in home care than in the nursing home care setting. Thus. in this sample for elderly patients with extreme physical impairment, the cost of home care exceeded the cost of nursing home care.

• Korean Journal of Cognitive Science
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• v.28 no.4
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• pp.245-265
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• 2017

Recently, studies on cognitive control revealed that the optimal level of control is determined on the basis of reward and cost. The value of reward can be subjective and therefore, the optimal control strength can vary accordingly. The inconsistent effect of aging on cognitive control can be the result of flexible adjustment of control signal strength made by the older subjects. In other words, the elderly people maintains the ability to set the optimal level of control, which is known as the function of the dorsal anterior cingulate cortex. On the other hand, the age-related decline in cognitive control is obvious in rule maintenance and inhibition, which has to do with the function of lateral prefrontal cortex. In this study, we had young and old adults perform go-no go task and compared the behavioral and neural results for different reward conditions. Both age groups showed the best performance and the largest ERN amplitude when the reward was most appealing to them. And there was no age effect in ERN amplitude even though older adults' d' and accuracy was inferior to younger participants. These findings suggest that the effect aging on different cognitive control processes can be asymmetric.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.7
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• pp.3095-3111
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• 2018

Spectrum sensing (SS) is one of the fundamental tasks for cognitive radio. In SS, decisions can be made via comparing the test statistics with a threshold. Conventional adaptive algorithms for SS usually adjust their thresholds according to the radio environment. This paper concentrates on the issue of adaptive SS whose threshold is adjusted based on the Markovian behavior of primary user (PU). Moreover, Bayesian cost is adopted as the performance metric to achieve a trade-off between false alarm and missed detection probabilities. Two novel adaptive algorithms, including Markov Bayesian energy detection (MBED) algorithm and IMBED (improved MBED) algorithm, are proposed. Both algorithms model the behavior of PU as a two-state Markov process, with which their thresholds are adaptively adjusted according to the detection results at previous slots. Compared with the existing Bayesian energy detection (BED) algorithm, MBED algorithm can achieve lower Bayesian cost, especially in high signal-to-noise ratio (SNR) regime. Furthermore, it has the advantage of low computational complexity. IMBED algorithm is proposed to alleviate the side effects of detection errors at previous slots. It can reduce Bayesian cost more significantly and in a wider SNR region. Simulation results are provided to illustrate the effectiveness and efficiencies of both algorithms.

• Journal of Korean Academy of Nursing
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• v.34 no.1
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• pp.191-201
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• 2004

Purpose: This study aimed to evaluate economic viability of public health center visiting nurse services for the low-income elderly with long-term care needs. Method: The sample consisted of 252 community dwelling elderly who enrolled in public health center visiting nurse services for three months or more. Data was collected on physical (ADL and IADL) and cognitive impairments of the elderly, contents and frequency of visiting nurse services, cost per visit, and costs of alternative services for long-term care. Result: The mean score of ADL and IADL levels of the elderly was 2.80.4904, which indicated these patients were mostly independent. Eighty four percent of the elderly subjects were cognitively intact. Among visiting nurse services supplied, providing assessment was 34%, followed by education and counseling 26%, medication 22%, and referral. The mean cost per visit was 17,824.1 won, which transformed into a total cost per person per year of 161,130.2 won. Comparing the cost of a visiting nurse service with those of other long-term care alternatives, the visiting nurse service was the least costly alternative, followed by an outpatient clinic, hospital based home care, and nursing home. Conclusion: Overall, the results of the study provide evidence of the economic viability of visiting nurse services for the low-income elderly among long-term care alternatives.