• Convergence Security Journal
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• v.18 no.1
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• pp.19-31
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• 2018

As the ICT technologies advance, the unprecedently large amount of digital data is created, transferred, stored, and utilized in every industry. With the data scale extension and the applying technologies advancement, the new services emerging from the use of large scale data make our living more convenient and useful. But the cybercrimes such as data forgery and/or change of data generation time are also increasing. For the data security against the cybercrimes, the technology for data integrity and the time verification are necessary. Today, public key based signature technology is the most commonly used. But a lot of costly system resources and the additional infra to manage the certificates and keys for using it make it impractical to use in the large-scale data environment. In this research, a new and far less system resources consuming signature technology for large scale data, based on the Hash Function and Merkle tree, is introduced. An improved method for processing the distributed hash trees is also suggested to mitigate the disruptions by server failures. The prototype system was implemented, and its performance was evaluated. The results show that the technology can be effectively used in a variety of areas like cloud computing, IoT, big data, fin-tech, etc., which produce a large-scale data.

• Journal of Broadcast Engineering
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• v.24 no.3
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• pp.411-419
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• 2019

Nowadays we are not able to consider and imagine anything without taking into account what is called Artificial Intelligence. Even broadcasting media technologies could not be thought of outside this newly emerging technology of A.I.. Since the last part of 20th century, this technology seemingly is accelerating it's development thanks to an unbelievably enormous computational capacity of data information treatments. In conjunction with the firmly established worldwide platform companies like GAFA(Google, Amazon, Facebook, Apple), the key cutting edge technologies dubbed NBIC(Nanotech, Biotech, Information Technology, Cognitive science) converge to change the map of the current civilization by affecting the human relationship with the world and hence modifying what is essential in humans. Under the sign of the converging technologies, the relatively recently coined concepts such as 'trans(post)humanism' are emerging in the academic sphere in the North American and Major European regions. Even though the so-called trans(post)human movements are prevailing in the major technological spots, we have to say that these terms do not yet reach an unanimous acceptation among many experts coming from diverse fields. Indeed trans(post)humanism as a sort of obscure term has been a largely controversial trend. Because there have been many different opinions depending on scientific, philosophical, medical, engineering scholars like Peter Sloterdijk, K. N. Hayles, Neil Badington, Raymond Kurzweil, Hans Moravec, Laurent Alexandre, Gilbert Hottois just to name a few. However, considering the highly dazzling development of artificial intelligence technology basically functioning in conjunction with the cybernetic communication system firstly conceived by Nobert Wiener, MIT mathematician, we can not avoid questioning what A. I. signifies and how it will affect the current media communication environment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.702-708
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• 2018

3D printing technology is attracting increasing attention as a key technology of the fourth industrial revolution that can change the production paradigm of existing industries. The introduction of construction 3D printing technology has been slower than other industries because of the characteristics of the construction field. On the other hand construction automation using 3D printing is required to reduce the production population, as well as improve productivity and safety. In this study, a construction 3D printing work breakdown structure and link method to a standard estimation system were developed as a preliminary preparation for introducing 3D printing to construction. Based on expert consultation on construction and 3D printing, a hypothetical scenario was developed based on existing construction 3D printing technology. According to the scenario, 16 kinds of works required for 3D printing construction work were derived. The existing work breakdown structure and standard estimation system were analyzed, and the 3D printing work was linked. 3D printing works that were the same as the existing breakdown structure were found, and non-existent works were added to the similar breakdown structure. These results are expected to be helpful for future 3D printing construction management and cost estimation. The actual standard estimation system through 3D printing work will need to be calculated.

• Journal of The Korean Association For Science Education
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• v.39 no.2
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• pp.263-277
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• 2019

This study analyzed the current use of science-related test tools in affective area in Korean academic journals for the last 30 years since 1989 and the cases of modification of the original tools related to the tools. This provides practical information on the development and improvement of test tools in the future and offers the basis for developing valid test tools. The study was conducted in two stages. We analyzed the status of 88 domestic science education researches dealing with testing tools related affective characteristics and 57 domestic and foreign resource tools referenced by them. After that, we compared the characteristics of the five cases in which the original tool was revised and the concrete item correction examples. The results were analyzed as follows: topics that have emerged continuously or that have recently begun to appear in domestic research, the research situations according to their purpose and measurement methods used by the tool, and use state of original tools. The background and key points of revision were analyzed for the five tools, TOSRA, SAI, PISA items, STEBI-A/B, SMQ, whose revision process were disclosed. In addition, the changes of the items were analyzed by comparing the four test items with the questions before and after the revision. As a result of item analysis, item improvement was proceeding in the direction of enhancing readability, clarifying meaning, and changing items according to change of sub constructs. The implications of this study are as follows: notes on interpreting the results obtained from the tool with multiple mixed constructs, the possibility of the testing tool that broadens the horizon of the research, error recognition in the subjective self-report, and notes when applying test tools from other disciplines to science.

• Journal of Electrodiagnosis and Neuromuscular Diseases
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• v.20 no.2
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• pp.98-105
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• 2018

Objective: To evaluate whether the increase of the amplitude of motor evoked potentials (MEPs) during surgery can imply favorable prognosis postoperatively in spinal cord tumor surgery. Method: MEPs were monitored in patients who underwent spinal cord tumor surgery between March 2016 and March 2018. Amplitude changes at the end of monitoring compared to the baselines in limb muscle were analyzed. Minimum and maximum changes were set to $MEP_{min}$ (%) and $MEP_{max}$ (%). Strengths of bilateral 10 key muscles which were documented a day before ($Motor_{pre}$), 48 h ($Motor_{48h}$) and 4 weeks ($Motor_{4wk}$) after the surgery were reviewed. Results: Difference of $Motor_{48h}$ from $Motor_{pre}$ ($Motor_{48h-pre}$) and $Motor_{4wk}$ from $Motor_{pre}$ ($Motor_{4wk-pre}$) positively correlated with $MEP_{min}$, suggesting that smaller the difference of MEPs amplitude, less recovery of muscle strength. There was a negative correlation between the amount of bleeding and $MEP_{min}$, indicating that the greater the amount of bleeding, the smaller the $MEP_{min}$, implying that MEPs amplitude is less likely to improve when the amount of bleeding is large. It also showed significant difference between patients with improved or no change of motor status and patients with motor deterioration after surgery according to anatomical tumor types. Conclusion: Improve of muscle strength was less when the increase of MEPs amplitude was small, and improvement of MEPs amplitude was less when the amount of bleeding was large. Correlation between changes of status of muscle strength after surgery and tumor types was observed. With amplitude increase in MEPs monitoring, restoration of muscle strength can be expected.

• Journal of the Korea Computer Graphics Society
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• v.27 no.3
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• pp.55-63
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• 2021

This study proposes an interface for providing mobile interaction suitable for mobile virtual reality (VR) and analyzes it through comparative experiments. The proposed interface is premised on not using additional equipment except for the mobile head-mounted display(HMD) in consideration of accessibility and usability. And the interface that controls the movement interaction using the user's gaze is designed in two phases. The key is to minimize the occurrence of negative factors such as VR sickness that can be caused by straight line movement in virtual reality. To this end, two phases are designed: an interface composed of forward/backward buttons to move the gaze toward the ground, and an interface composed of left and right buttons on the front in consideration of the gaze change in real walking motion. An application that can compare and analyze movement interactions through the proposed interface is produced, and a survey experiment is conducted to analyze the user's satisfaction with the interface experience and the negative impact on the movement process. It was confirmed that the proposed movement interaction reduced negative effects such as VR sickness along with a satisfactory interface experience for users.

• The Journal of Internal Korean Medicine
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• v.41 no.6
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• pp.1100-1118
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• 2020

Objectives: The purpose of this study was to assess the effects of acupuncture as a treatment for allergic rhinitis (AR). We used a meta-analysis and systematic review to analyze the results of randomized controlled trials (RCTs) that applied acupuncture to AR patients. Methods: The key question assessed the effects of acupuncture on patients with AR, and we included only RCTs. We searched the KoreaMed, NDSL, KMBASE, Koreantk, OASIS, PubMed, EMBASE, and Cochrane databases, with no language restriction. We assessed risk of bias with the Cochrane Risk of Bias tool. The random effects model was used to adjust for the heterogeneity of the included studies, and the effect sizes between two groups were reported as mean differences (MD) and risk ratios (RR). Results: Twelve RCTs were analyzed, with a total of 1788 participants; 824 participants were in the treatment group (i.e., acupuncture) and 964 were in the control group (sham acupuncture, western medicine, or waitlist). The meta-analysis results of 7 RCTs comparing the therapeutic efficacy of acupuncture with that of sham acupuncture showed a statistically significant difference (p<0.05) in the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) and the Change of Total Nasal Symptom Score (TNSS). The meta-analysis of 4 RCTs comparing the therapeutic efficacy of acupuncture with western medicine showed statistically significant differences (p<0.05) in the RQLQ but not in the changes in effective rate (p>0.05). Conclusions: Acupuncture can be an effective treatment for AR, but more studies are required to enhance the level of evidence and to confirm safety.

• Korean Journal of Construction Engineering and Management
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• v.22 no.2
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• pp.21-30
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• 2021

The existing construction industry is classified into industries with low productivity compared to other industries. In order to solve the decline in productivity in the construction industry, the world is focusing on off-site construction (OSC), which is about 40% more productive than existing construction methods. This high productivity is possible because the three stages of production, transport to the site, and site assembly are consistently maintained in a continuous flow. This study conducted a functional survey through literature review, preliminary field survey, questionnaire, and expert interview. The surveyed function were classified into five categories: convenience, flexibility, manageability, communication, and safety, and the functional characteristics of flexibility, manageability, and communication were high. Because of the change according to the construction progress, the production schedule of the factory, and the variety of transportation time required. Finally, A functional block diagram was developed based on the 15 functions corresponding with an average score of 4 or more in the surveyed function score result. If the OSC transport system is established through this study, It can contribute to a successful construction OSC project and increase productivity.

• Journal of Ecology and Environment
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• v.44 no.4
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• pp.264-274
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• 2020

Background: Climate change has altered the various ecosystem processes including forest ecosystem in Himalayan region. Although the high mountain natural forests including treelines in the Himalayan region are mainly reported to be temperature sensitive, the temperature-related water stress in an important growth-limiting factor for middle elevation mountains. And there are very few evidences on growth performance of planted forest in changing climate in the Himalayan region. A dendrochronological study was carried out to verify and record the impact of warming temperature tree growth by using the tree cores of Pinus roxburghii from Batase village of Dhulikhel in Central Nepal with sub-tropical climatic zone. For this total, 29 tree cores from 25 trees of P. roxburghii were measured and analyzed. Result: A 44-year long tree ring width chronology was constructed from the cores. The result showed that the radial growth of P. roxburghii was positively correlated with pre-monsoon (April) rainfall, although the correlation was not significant and negatively correlated with summer rainfall. The strongest negative correlation was found between radial growth and rainfall of June followed by the rainfall of January. Also, the radial growth showed significant positive correlation with that previous year August mean temperature and maximum temperature, and significant negative correlation between radial growth and maximum temperature (Tmax) of May and of spring season (March-May), indicating moisture as the key factor for radial growth. Despite the overall positive trend in the basal area increment (BAI), we have found the abrupt decline between 1995 and 2005 AD. Conclusion: The results indicated that chir pine planted population was moisture sensitive, and the negative impact of higher temperature during early growth season (March-May) was clearly seen on the radial growth. We emphasize that the forest would experience further moisture stress if the trend of warming temperatures continues. The unusual decreasing BAI trend might be associated with forest management processes including resin collection and other disturbances. Our results showed that the planted pine forest stand is sub-healthy due to major human intervention at times. Further exploration of growth climate response from different climatic zones and management regimes is important to improve our understanding on the growth performance of mid-hill pine forests in Nepal.

• Applied Chemistry for Engineering
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• v.22 no.5
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• pp.551-554
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• 2011

One of the key issues in the research of organic field-effect transistors (OFETs) is the low-voltage operation. To address this issue, we synthesized poly(styrene-r-benzocyclobutene-r-methyl methacrylate) (P(S-r-BCB-r-MMA)) as a thermally cross-linkable gate dielectrics. The P(S-r-BCB-r-MMA) showed high quality dielectric properties due to the negligible volume change during the cross-linking. The pentacene FETs based on the 34 nm-thick P(S-r-BCB-r-MMA) gate dielectrics operate below 5 V. The P(S-r-BCB-r-MMA) gate dielectrics yielded high device performance, i.e. a field-effect mobility of $0.25cm^2/Vs$, a threshold voltage of -2 V, an sub-threshold slope of 400 mV/decade, and an on/off current ratio of ${\sim}10^5$. The thermally cross-linkable P(S-r-BCB-r-MMA) will provide an attractive candidate for solution-processable gate dielectrics for low-voltage OFETs.