• KIPS Transactions on Computer and Communication Systems
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• v.11 no.9
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• pp.305-316
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• 2022

With the flood of digital data owing to the Internet of Things and big data, cloud service providers that process and store vast amount of data from multiple users can apply duplicate data elimination technique for efficient data management. The user experience can be improved as the notion of edge computing paradigm is introduced as an extension of the cloud computing to improve problems such as network congestion to a central cloud server and reduced computational efficiency. However, the addition of a new edge device that is not entirely reliable in the edge computing may cause increase in the computational complexity for additional cryptographic operations to preserve data privacy in duplicate identification and elimination process. In this paper, we propose an efficiency-improved duplicate data elimination protocol while preserving data privacy with an optimized user-edge-cloud communication framework by utilizing a trusted execution environment. Direct sharing of secret information between the user and the central cloud server can minimize the computational complexity in edge devices and enables the use of efficient encryption algorithms at the side of cloud service providers. Users also improve the user experience by offloading data to edge devices, enabling duplicate elimination and independent activity. Through experiments, efficiency of the proposed scheme has been analyzed such as up to 78x improvements in computation during data outsourcing process compared to the previous study which does not exploit trusted execution environment in edge computing architecture.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.1
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• pp.45-52
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• 2023

The power generation method using expensive diesel has operation problems such as high cost diesel generator and a lack of reserved power due to increase of power demand in some islands, requiring expansion of power generation facilities. To solve this problems, it is necessary to improve the efficiency of power generation facilities through an ORC(Organic Rankin Cycle) system application that uses waste heat as a heat source. Therefore, localized application technology of price competitive and highly reliable ORC power generation system is needed, and optimization technology of generators is having great effect, so this study performed two generator designs to get a high-efficiency generator with an optimized 30kW output. The comparison of simulation data for two designed models showed that a generator with SPM factor of 46.2% had an efficiency of 92.1% and a power ouput of about 23.2kW based on 12,000rpm, a generator with SPM factor of 44.46%, had a power output of 27.9kW and efficiency of 93.6% based on above rpm. For the verification of improved design model with SPM factor of 44.46%, the prototype test system with 110kW motor dynamometer was installed and got to the efficiency of 92.08% with conditions of the rated capacity 25kW at 12,000rpm, the test results of prototype generator showed the validity of generator design.

• Journal of Service Research and Studies
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• v.12 no.3
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• pp.144-157
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• 2022

This study began by pointing out the problem of domestic media reporting on 'fake news' regulations that frequently appear through the French 'Les proposals de loi control de l'information'case, while still approaching with different standards and perspectives on where to see fake news. In the age of 'social network services', the answer to what the media is, what the news is, and who the reporter is increasingly difficult. While reviewing the long history and background of the spread of fake news examined in this study, it was confirmed that could not determine the concept and scope of fake news, punished, regulated, controlled, or judged simply by one standard. From the perspective of 'freedom of expression' set by the law, we have the authority to express our opinions freely. In addition, 'online' space is a place where fake news is generated and spread, but at the same time, there is plenty of room to act as an antidote. In the end, the only alternative to the damage of long-term fake news will be to create a media environment that allows more high-quality "real news" to pour out, allowing us to develop our ability to judge reliable information through balanced competition among various news in the free market of ideas.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.16 no.3
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• pp.123-129
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• 2023

if we know what we're looking at, we can get a lot of information. Due to the development of eye tracking, Information on gaze point can be obtained through software provided by various eye tracking equipments. However, it is difficult to estimate accurate information such as the actual gaze depth. If it is possible to calibrate the eye tracker with the actual gaze depth, it will enable the derivation of realistic and accurate results with reliable validity in various fields such as simulation, digital twin, VR, and more. Therefore, in this paper, we experiment with acquiring and calibrating raw gaze depth using an eye tracker and software. The experiment involves designing a Deep Neural Network (DNN) model and then acquiring gaze depth values provided by the software for specified distances from 300mm to 10,000mm. The acquired data is trained through the designed DNN model and calibrated to correspond to the actual gaze depth. In our experiments with the calibrated model, we were able to achieve actual gaze depth values of 297mm, 904mm, 1,485mm, 2,005mm, 3,011mm, 4,021mm, 4,972mm, 6,027mm, 7,026mm, 8,043mm, 9,021mm, and 10,076mm for the specified distances from 300mm to 10,000mm.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.16 no.2
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• pp.104-108
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• 2023

Because of recent expansion of the electric car market. it is highly growing that should be supplemented its performance and safely issue. The EMI problem due to the interlocking of electrical components that causes various safety problems such as fire in electric vehicles is emerging every time. We strive to achieve optimal charging efficiency by combining various technologies and reduce radioactive noise among the EMI noise of a weirless charging control module, one of the important parts of an electric vehicle was designed and tested. In order to analyze the EMI problems occurring in the wireless charging control module, the optimized wireless charging control module by applying the optimization design technology by learning the accumulated test data for critical factors by utilizing the Python-based script function in the Ansys simulation tool. It showed an EMI noise improvement effect of 25 dBu V/m compared to the charge control module. These results not only contribute to the development of a more stable and reliable weirless charging function in electric vehicles, but also increase the usability and efficiency of electric vehicles. This allows electric vehicles to be more usable and efficient, making them an environmentally friendly alternative.

• Korean journal of communication and information
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• v.32
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• pp.49-73
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• 2006

During the past decades, public opinion polls have become an ubiquitous tool for probing the complexity of people's beliefs and attitudes on a wide variety of issues. Especially since the late 1970s, the use of polls by news organizations has increased dramatically. Along with the proliferation of traditional polls, in the past few years pollsters and news organizations have come to recognize the advantages of online polls. Increasingly there has been more effort to take the pulse of the public through the Internet. With the Internet's rapid growth during the past years, advocates of online polling often emphasize the relative advantages over traditional polls. Researchers from Harris Black International Ltd., for example, argue that "Internet polling is less expensive and faster and offers higher response rates than telephone surveys." Moreover, since many of the newer online polls draw respondents from large databases of registered Internet users, results of online polls have become more balanced. A series of Harris Black online polls conducted during the 1998 gubernatorial and senatorial elections, for example, has accurately projected the winners in 21 of the 22 races it tracked. Many researchers, however, severely criticize online polls for not being representative of the larger population. Despite the often enormous number of participants, Internet users who participate in online polls tend to be younger, better educated and more affluent than the general population. As Traugott pointed out, the people polled in Internet surveys are a "self selected" group, and thus "have volunteered to be part of the test sample, which could mean they are more comfortable with technology, more informed about news and events ... than Americans who aren't online." The fact that users of online polls are self selected and demographically very different from Americans who have no access to the Internet is likely to influence the estimates of what the majority of people think about social or political issues. One of the goals of this study is therefore to analyze whether people perceive traditional and online public opinion polls differently. While most people might not differentiate sufficiently between traditional random sample polls and non representative online polls, some audiences might perceive online polls as more useful and representative. Since most online polls allow some form of direct participation, mostly in the form of an instant vote by mouse click, and often present their findings based on huge numbers of respondents, consumers of these polls might perceive them as more accurate, representative or reliable than traditional random sample polls. If that is true, perceptions of public opinion in society could be significantly distorted for those who rely on or participate in online polls. In addition to investigating how people perceive random sample and online polls, this study focuses on the perceived impact of public opinion polls. Similar to these past studies, which focused on how public opinion polls can influence the perception of mass opinion, this study will analyze how people perceive the effects of polls on themselves and other people. This interest springs from prior studies of the "third person effect," which have found that people often tend to perceive that persuasive communications exert a stronger influence on others than on themselves. While most studies concerned with the political effects of public opinion polls show that exit polls and early reporting of election returns have only weak or no effects on the outcome of election campaigns, some empirical findings suggest that exposure to polls can move people's opinions both toward and away from perceived majority opinion. Thus, if people indeed believe that polls influence others more than themselves, perceptions of majority opinion could be significantly altered because people might anticipate that others will react more strongly to poll results.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.26 no.3
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• pp.197-208
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• 2015

Objectives : The purposes of this study were to examine the reliability and validity of the Korean version of Social Communication Questionnaire (K-SCQ) and to determine cut-off scores for diagnosis of autism spectrum disorder (ASD). Methods : A total of 166 subjects with ASD and their 186 unaffected siblings were recruited through child psychiatry clinics of university hospitals. Board certified child psychiatrists screened all probands suspected to have ASD based on the Diagnostic and Statistical Manual of Mental Disorders, fourth edition. To confirm the diagnoses, the Korean versions of the Autism Diagnostic Observation Schedule and the Autism Diagnostic Interview-Revised (K-ADI-R) were administered to all the subjects. All parents completed the K-SCQ and Social Responsiveness Scale (SRS). The non-ASD siblings were evaluated with the same instruments as the probands with ASD. We performed a factor analysis to examine the structure of K-SCQ. For testing the validity of K-SCQ, we compared the difference in Lifetime and Current scores of probands with ASD and their non-ASD siblings using t-test and analysis of covariance. Correlations between the K-SCQ and other measurements of ASD symptomatology, including K-ADI-R totals and domain scores and SRS, were examined. Receiver operation characteristic curve analysis was performed to extract cutoff scores discriminating affection status. Results : Four factors were extracted through factor analysis of K-SCQ ; 1) social relation and play, 2) stereotyped behavior, 3) social behavior, and 4) abnormal language. Cronbach's internal consistency was .95 in K-SCQ Lifetime, and .93 in K-SCQ Current. There were significant differences in total score of K-SCQ, both in Lifetime and Current between the ASD group and non-ASD siblings group (p<.05). K-SCQ scores were significantly correlated with K-ADI-R subdomain scores and SRS total scores (p<.05). The best-estimate cut-off scores of K-SCQ for diagnosis of ASD were 12 for 48 months and over, and 10 for below 47 months. Conclusion : Our findings suggest that the K-SCQ is a reliable and valid instrument for screening autistic symptoms in the Korean population. Lower cut-off scores than the original English version might be considered when using it as a screening instrument of ASD.

• Journal of Hospice and Palliative Care
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• v.14 no.1
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• pp.28-33
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• 2011

Purpose: Recognition of impending death is crucial not only for efficient communication with the caregiver of the patient, but also determination of the time to refer to a separate room. Current studies simply list the events 'that have already occurred' around 48 hours before the death. This study is to analyze the predictability of each event by comparing the time length from 'change' to death. Methods: Subjects included 160 patients who passed away in a palliative care unit in Incheon. The analysis was limited to 80 patients who had medical records for the last week of their lives. We determined 9 symptoms and 8 signs, and established the standard of 'significant change' of each event before death. Results: The most common symptom was increased sleeping (53.8%) and the most common sign was decreased blood pressure (BP) (87.5%). The mean time to death within 48 hours was 46.8% in the case of resting dyspnea, 13.6% in the ease of low oxygen saturation, and 36.9% in the case of decreased BP. The symptom(s) which had the highest positive predictive value (PV) for death within 48 hours was shown to be resting dyspnea (83%), whereas the combination of resting dyspnea and confusion/delirium (65%) had the highest negative PV. As for the most common signs before death within 48 hours, the positive PVs were more than 95%, and the negative PV was the highest when decreased BP and low oxygen saturation were combined. The difference in survival patterns between symptoms and signs was significant. Conclusion: The most reliable symptoms to predict the impending death are resting dyspnea and confusion/delirium, and decline of oxygen saturation and BP are the reliable signs to predict the event.

• Journal of Korean Society of Transportation
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• v.26 no.3
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• pp.31-40
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• 2008

There have been a lot of efforts to find more accurate evaluation methods for traffic signal control effectiveness for a long period of time. Nowadays a newly advanced method called HILSS, 'Hardware-in-the-Loop-Simulation System', is used to evaluate the overall traffic control's effectiveness including physical control environments like communication conditions, hardware performance, controller's mechanical operations and so on. In this study, an Online-HILSS model has been developed, which runs on CORSIM(5.0) micro traffic simulation model on-lined to COSMOS. For the verification of the model, three tests are performed as follows; (1) a comparison of TMC's timing plan with the simulated green interval, (2) as a case study, a delay distribution comparison of the online simulation with the CORSIM stand-alone simulation. The result of the first test shows that the model can run the simulation green interval by TMC's timing plan correctly. The result of second test shows that the online simulation of the model brings the same simulation results with the CORSIM offline simulation in case of the same timing plan. These results mean that the online evaluation model could be a reliable tool to measure a real-time signal control effectiveness of a wide area street network with the HILSS method.

• Journal of Digital Convergence
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• v.15 no.11
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• pp.251-259
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• 2017

Recently, the smart healthcare industry that grafted the Internet of Things (IoT) onto the healthcare and medical services is being highlighted. Smart healthcare refers to the healthcare and medical services offered on the basis of information communication technologies including application, wearable devices and platforms, etc. The number of next generation smart healthcare devices are increasing in the smart healthcare industry through the combination of information technology (IT) and Bio Technology (BT), which are the most active areas among the 6T, which are the areas of the next generation industry. With the emergence of a diverse range of smart healthcare systems or devices, whether the smart healthcare system can be linked with other systems organically and the security and quality of the system have become important elements of evaluation. In this Study, the characteristics and service types of smart healthcare systems were examined, and the trends in the technology and industry of the smart healthcare system were analyzed. Moreover, this Study aims to develop the evaluation method for security and standards for quality evaluation by deducing the factors for the evaluation of smart healthcare system on the basis of the results of aforementioned examination. It is anticipated that this can induce improvement of quality and development of highly reliable products of a smart healthcare system, and will become the core technology to substitute the technology protection barrier.