• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.8
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• pp.2490-2506
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• 2022

In Mobile Edge Computing (MEC), attackers can speculate and mine sensitive user information by eavesdropping wireless channel status and offloading usage pattern, leading to user privacy leakage. To solve this problem, this paper proposes a Privacy-preserving and Energy-efficient Offloading Algorithm (PEOA) based on Lyapunov optimization. In this method, a continuous Markov process offloading model with a buffer queue strategy is built first. Then the amount of privacy of offloading usage pattern in wireless channel is defined. Finally, by introducing the Lyapunov optimization, the problem of minimum average energy consumption in continuous state transition process with privacy constraints in the infinite time domain is transformed into the minimum value problem of each timeslot, which reduces the complexity of algorithms and helps obtain the optimal solution while maintaining low energy consumption. The experimental results show that, compared with other methods, PEOA can maintain the amount of privacy accumulation in the system near zero, while sustaining low average energy consumption costs. This makes it difficult for attackers to infer sensitive user information through offloading usage patterns, thus effectively protecting user privacy and safety.

• Journal of Distribution Science
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• v.21 no.6
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• pp.51-68
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• 2023

Purpose: This study aims to explore the impact of green products' claim skepticism on green purchase intention and further investigates the moderating role of environmental concern in the relationship. This study, by drawing the persuasion knowledge model expected that ambiguity avoidance penalizes less familiar brands than familiar brands. Further, the present study building on Hofstede's cultural dimension, specifically, uncertainty avoidance, undertook a scenario to understand any difference that exist between uncertainty avoidance cultural groups. This study also investigates gender differences in green claim skepticism and proclivity to purchase green products. Research design, data, and methodology: For analyzing the relationship relevant hypotheses were designed, and R-programming software was used. To test the hypotheses two independent sample t-test and regression analysis were carried out. Results: The results suggest that consumers' skepticism toward green claims influenced the intention to purchase eco-friendly products. The study finding also confirms the effect is moderated by environmental concern. Also, the findings of two scenarios reveal that consumers in high uncertainty avoidance culture exhibited a greater level of skepticism for green print advertising and green packaging claims when the brand in the advertising and packaging was unfamiliar than when it was familiar. Conclusions: To alter the negative effect of skepticism the consumer should believe the environmental claims are valid so that they can contribute to solving sustainability issues.

• Journal of Korea Entertainment Industry Association
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• v.15 no.8
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• pp.107-116
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• 2021

In recent years, the research on audience satisfaction after watching programs has been carried out in various fields. However, there is no precedent for the study of simply analyzing the influencing factors of audience satisfaction with the newly established CCTV-9 channel. For CCTV-9, how to explore the strategy of industrial development based on the needs of the audience in the era of big data is a very important part. This article exploratively focuses on the influencing factors related to CCTV-9 audience satisfaction. Using questionnaires, 101 samples of the satisfaction with the channel of men and women of different ages, education backgrounds, majors, and incomes were collected to test, and 9 hypotheses were tentatively proposed as relevant influencing factors of channel satisfaction. Through empirical analysis, this research searches for the determinants. The reliability and validity of the measurement were properly analyzed, and all hypotheses were statistically tested. The empirical results show that: subject matter, program format, program scheduling, program broadcast time, channel advertising, simulcast series of documentaries, diversified communication platforms, brand image packaging and audience satisfaction are significantly positively correlated.

• Information Systems Review
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• v.20 no.4
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• pp.59-78
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• 2018

With the advent of the various device types and marketing communication, customer's search and purchase behavior have become more complex and segmented. However, extant research on multichannel marketing effects of the purchase funnel has not reflected the specific features of device User Interface (UI) and User Experience (UX). In this study, we analyzed the marketing channel effects of multi-device shoppers using a unique click stream dataset from global online retailers. We examined device types that activate online shopping and compared the differences between marketing channels that promote visits. In addition, we estimated the direct and indirect effects on visits and purchase revenue through customer's accumulated experience and channel conversions. The findings indicate that the same customer selects a different marketing channel according to the device selection. These results can help retailers gain a better understanding of customers' decision-making process in multi-marketing channel environment and devise the optimal strategy taking into account various device types. Our empirical analyses yield business implications based on the significant results from global big data analytics and contribute academically meaningful theoretical framework using an economic model. We also provide strategic insights attributed to the practical value of an online marketing manager.

• Korean Journal of Ecology and Environment
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• v.34 no.3 s.95
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• pp.223-238
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• 2001

Longitudinal distribution of the fish fauna of the 20 main channel and tributary sites in the Nakdong River was investigated from July 1999 to December 2000. A total of 4,791 individuals of fisHes were collected from three to seven sampling programs of all study sites and 48 species of 17 families were collected. Dominant family was Cyprinidae (25 species, relative abundance (RA): 91.8%). Zacco platypus (RA: 18.0%) was found to be the most abundant inhabitant. Subdominant species were Opsariichthys bidens (17,1%), Squalidus chankaensis tsuchigae (13.2%), Hemibarbus labeo (9.9%), and Z. temmincki (8.2%). Among the total species, 12 species were identified as endemic species (4 families, 24.5% of 1,172 individuals). Four exotic fishes were collected (Carassius cuvieri, 25 indv.; Micropterus salmoides, 214 indv.; Lipomis macrochirus, 14 indv.; Oreochromis niloticus, 6 indv.). M. salmoides was distributed in mid to lower part of the Nakdong River. As the result of cluster analysis, sampling sites were divided into three groups (upper, middle and lowerpart). Site below Gumi (St. 10) were considered as the lower part of the Nakdong River. Combined with previous surveys, about 80 species are present in the main channel and tributaries of the Nakdong River. Since the middle of 1990s, population density of the M. salmoides rapidly increased in the stagnant lower part of the river(RA 8.8% in lower 5 sites). The feeding strategy of M. salmoides was "generalized" on Daphnia sp. (<100 mm), and "specialization" about Cladocera (<150 mm) and Insecta(<200 mm).

• Korean Journal of Optics and Photonics
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• v.35 no.3
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• pp.107-114
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• 2024

In this study, the feasibility of using the covariance-matrix-adaptation-evolution-strategy (CMA-ES) algorithm in a multichannel coherent-beam-combining (CBC) system was experimentally verified. We constructed a multichannel CBC system utilizing a spatial light modulator (SLM) as a multichannel phase-modulator array, along with a coherent light source at 635 nm, implemented the stochastic-parallel-gradient-descent (SPGD) and CMA-ES algorithms on it, and compared their performances. In particular, we evaluated the characteristics of the CMA-ES and SPGD algorithms in the CBC system in both 16-channel rectangular and 19-channel honeycomb formats. The results of the evaluation showed that the performances of the two algorithms were similar on average, under the given conditions; However, it was verified that under the given conditions the CMA-ES algorithm was able to operate with more stable performance than the SPGD algorithm, as the former had less operational variation with the initial phase setting than the latter. It is emphasized that this study is the first proof-of-principle demonstration of the CMA-ES phase-control algorithm in a multichannel CBC system, to the best of our knowledge, and is expected to be useful for future experimental studies of the effects of additional channel-number increments, or external-phase-noise effects, in multichannel CBC systems based on the CMA-ES phase-control algorithm.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.2
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• pp.547-566
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• 2014

This study investigates the decisive factors affecting the survival or collapse of cable networks in the Korean paid broadcasting market from 1993 to 2010. The effects of performance variables discussed in previous studies were verified through survival analyses. According to the results, the most influential factors in the survival of cable networks were horizontal integration (MPP), channel genre, the scheduling of HDTV content, and the proportion of access program scheduling. These findings imply that the differentiation strategy of content suppliers is the most decisive factor among all business performance-related factors. Specifically, the content supply power and strategy of the program provider (PP) have the greatest influence on cable network viability. The present study is meaningful as the first attempt to establish the performance of PPs in Korean pay broadcasting markets through the viewpoint of organizational mortality. Accordingly, the present study can supplement the results of cross-sectional studies conducted with smaller samples.

• Advances in aircraft and spacecraft science
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• v.4 no.1
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• pp.53-64
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• 2017

Aerospace Launch Vehicles (ALV) are generally designed with high reliability to operate in complete security through fault avoidance practices. However, in spite of such precaution, fault occurring is inevitable. Hence, there is a requirement for on-board fault recovery without significant degradation in the ALV performance. The present study develops an advanced fault recovery strategy to improve the reliability of an Aerospace Launch Vehicle (ALV) navigation system. The proposed strategy contains fault detection features and can reconfigure the system against common faults in the ALV navigation system. For this purpose, fault recovery system is constructed to detect and reconfigure normal navigation faults based on the sliding mode observer (SMO) theory. In the face of pitch channel sensor failure, the original gyro faults are reconstructed using SMO theory and by correcting the faulty measurement, the pitch-rate gyroscope output is constructed to provide fault tolerant navigation solution. The novel aspect of the paper is employing SMO as an online tuning of analytical fault recovery solution against unforeseen variations due to its hardware/software property. In this regard, a nonlinear model of the ALV is simulated using specific navigation failures and the results verified the feasibility of the proposed system. Simulation results and sensitivity analysis show that the proposed techniques can produce more effective estimation results than those of the previous techniques, against sensor failures.

• Journal of Environmental Science International
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• v.9 no.6
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• pp.443-447
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• 2000

Chonan and Asan city have been a focal point due to rapid development as the first station for Express Railroad and key cities West Coast Development Region. Gokgyo stream adjacent to the cities plays an important role as a drainage channel for an agriculture and a discharger of urban storm water. Waster quality of the stream has been deteriorating caused by pollution sources such as a untreated wastewater discharge and runoff from the watershed. In the study, we conducted 4 surveys in April, May, July, and September to understand the current state of water quality for the stream and to make it possibe to predict future water-quality variation for future development. The system runs on a personal computer under the windows enviroment and provides extensive graphic user interface(GUI) for user-friendly assessment. Using the pull-down menus provided by the GUI panel, the user is able to operate the system by pointing and clicking the icon to identify the state of water-quality at locations concerned. Furthermore, we developed an integrated watershed management system. The constructed system could be a useful tool as a decesion maker for pollution source control strategy.

• Journal of Information Technology Applications and Management
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• v.19 no.2
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• pp.249-263
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• 2012

Recently the open innovation is considered as one of the important issues for the survival strategy of a company in the industry. There have been several researches and practices on this topic. However, previous researches are mainly focused on the study of successful cases and some statistical analyses on the relationship between the open innovation and its performance. There are rare researches on the hindrance factors in the practical level. This paper tries to find some hinderance factors for the open innovation in Korean large-scale companies based on the WFGM(Want-Find-Get-Manage) model proposed by Gene Slowinski(2006). Especially this research focused on each processes of open innovation by in-depth interviews for two representative large companies in Korea. From the result of this research we come to know that the critical hindrance factor in the WANT step is the uncertain definition of the necessary technologies for the company. Issues on establishing and maintaining the innovation network are in the FIND step. Technology evaluation, technology introduction channel and technology copying issues are in the GET step. Communication issues, technology feasibility and lack of competition are in the MANAGE step. This paper finds some hindrance factors in each process step of open innovation, which gives some implications for the companies that want to adopt open innovation.