• Smart Structures and Systems
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• v.31 no.5
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• pp.485-500
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• 2023

Machine learning-based structural health monitoring (ML-based SHM) methods are researched extensively in the recent decade due to the availability of advanced information and sensing technology. ML methods are well-known for their pattern recognition capability for complex problems. However, the main obstacle of ML-based SHM is that it often requires pre-collected historical data for model training. In most actual scenarios, damage presence can be detected using the unsupervised learning method through anomaly detection, but to further identify the damage types would require prior knowledge or historical events as references. This creates the cold-start problem, especially for new and unobserved structures. Modal-based methods identify damages based on the changes in the structural global properties but often require dense measurements for accurate results. Therefore, a two-stage hybrid modal-machine learning damage detection scheme is proposed. The first stage detects damage presence using Principal Component Analysis-Frequency Response Function (PCA-FRF) in an unsupervised manner, whereas the second stage further identifies the damage. To solve the cold-start problem, mode shape assessment using the first mode is initiated when no trained model is available yet in the second stage. The damage identified by the modal-based method would be stored for future training. This work highlights the performance of the scheme in alleviating the cold-start issue as it transitions through different phases, starting from zero damage sample available. Results showed that single and multiple damages can be identified at an acceptable accuracy level even when training samples are limited.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.33 no.1
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• pp.99-116
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• 2023

The importance of data in the era of the 4th industrial revolution, a hyper-connected society based on information technology such as data and AI, is increasing, and the government is actively enacting and revising laws to revitalize the data economy. It is necessary to prevent and improve problems that may set an obstacle to the revitalization of the data industry or setting the wrong direction, such as possibility of conflict between the regulatory law(Personal Information Protection Act) and the Data Activation Act, differences in position by type of specialized agencies, performance scope of Data Specialist Organization and Expert Data Combination Agency, etc. In regard, I would like to analyze the role, current situation, and use cases of Expert Data Combination Agency, listen to field opinions, and derive and introduce measures to expand the role of Expert Data Combination Agency and improve them to vitalize the data economy

• The Korean Journal of Air & Space Law and Policy
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• v.30 no.2
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• pp.3-36
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• 2015

As of end of 2014, the population engaging in aviation activities for leisure has reached approximately 13 million, where approximately 356 cases involve a general aircraft, 200 cases involve light aircraft, and 636 cases involve an ULM. The industry for leisure has become a very promising industry in line with rapidly rising living standards which are expected to further increase in the future. The demand for such services is expected to increase over time. The purpose of this paper is to review the development and site selection of airfields in anticipation of these developments in the industry. While the government also has experience in the review of airfield location and candidate sites, it is not the government that carries out the actual construction. As such, the feasibility of the site needs to be verified in terms of actual construction. This study identified factors for Site Selection of factors through a review of related documents and existing research reports. A questionnaire was also used to collect the views of experts in the field, which was then analyzed. The Research model was confirmed in the layered form for an AHP analysis. The factors for Site Selection were identified as the technical / operational factors and economic / political elements for a two-stage configuration. The third step consisted of technical and operational elements. The final step is was constructed a total of 11 elements (weather, surface conditions, obstacle limitation surface, airspace conditions, operating procedures, noise problems, environmental issues, availability of facilities, construction and investment costs, contribution to the local economy, accessibility, demand / the proximity of demand). The surveys are conducted for more than 10 General and light aircraft pilots, professionals, and instructor. The analysis results showed a higher level in the technical / operating elements (73.2%) in the first step, while the next step sawa higher level of the operational elements (30.9%) than the other. The factors for Site Selection were any particular elements did not appear high, the weather conditions (17.5%), noise problems (19.8%), the proximity of demand (6%), accessibility (5.7%), environmental issues (11.1%), availability of facilities (8%), airspace conditions (7.9%), obstacle limitation surface (12%), construction and investment costs (4.2%) and to operating procedures (4.9%), contribution to the local economy (3.8%).

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.3-3
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• 2017

The question of how to establish sustainable agricultural systems has become as prominent as questions related to water, energy and climate change. High input/high output agriculture has brought with it many adverse effects; the massive deterioration of soil and water in both quantity and quality, increased greenhouse gas emissions and an increased prevalence of unsafe foods. Additionally, urbanization and climate change has worsened the shortage of farmland and reduced the supply of agricultural water. Given these challenges, maintaining, conserving and efficiently using agri-environmental resources, through fostering of sustainable agriculture, have emerged as key tasks in solving these problems. What is needed therefore is research, based on systematic and comprehensive empirical analyses, that can propose plans and methods for establishing an appropriate sustainable agricultural system. The empirical analysis of sustainable agricultural system is approached separately from economic, environmental and social aspects. An analysis of environment effect reveals that the available phosphate level is 1.3~2.1 times greater than the optimal amount in rice paddies, upland fields and orchards. Further examination has revealed that the excess nutrient is polluting both ground water and surface water. Analytical results for economic feasibility show that factors of production have been invested heavily in the rice crop. Under these conditions, sustainable agriculture, including low-input agriculture, appears to be a possible alternative that will facilitate simultaneous improvements in both economic feasibility and environment effects. Analysis results for sociality reveal that social factors include the value of producer, association and interior networks. Social conditions are comprised of leadership, consumers' awareness, education and conflict solutions. In addition, analysis as to the degree investments contribute to improving agricultural value added has revealed that the direct payment program is the most effective instrument. Experts confirm that economic feasibility can be improved by scientific and well-reasoned nutrient management on the basis of soil testing. Farmers pointed to 'economic factors' as being the largest obstacle to switching to the practice of sustainable agriculture. They also indicate 'uncertainty with regards to sustainable agriculture technology' as an impediment to practicing sustainable agriculture. Even so, farmers who believe environmental and regional issues to be the most pressing problems have expanded their practice of sustainable agriculture. The keys to establishing sustainable agriculture system are classified into the following four aspects. Firstly, from an economic aspect, the research indicates that agricultural policy needs to be integrated with environmental policy and that the function of market making based on the value chain needs to be revitalized. Secondly, from an environmental aspect, there is a need for an optimal resource management system to be established in the agricultural sector. In addition, sustainable agriculture practice will need to be extended with attendant environmentally-friendly and sustainable intensive technology also requiring further development. Thirdly, from a social aspect, green agriculture management needs to be fostered, technology and education extended, and social conflict mediated. Lastly, from a governance aspect, it will be necessary to strengthen good governance, assign and share suitable roles and responsibilities, build a cooperation system and utilize community supported agriculture.

• Journal of Navigation and Port Research
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• v.26 no.4
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• pp.419-426
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• 2002

The conventional RTK-GPS technique has many problems which are permission using RF wireless modem, influence of geographic obstacle using radio wave, frequency interference, finiteness of frequency resources. To solve these problems, in this paper, we designed the DGPS correction message transmission system as a method to substitute the RF wireless modem of RTK-DGPS receiver. Then the interface module was designed and implemented for linkage of GPS receiver and mobile phone. As a result worked differential surveying using receiving correction message using RS-232C and communication control, users of mobile station were worked differential surveying correction between mobile phones. Interface module system was received the same result of precision which was compared RF wireless modem system.

• Korean Journal of Social Welfare
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• v.69 no.3
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• pp.241-265
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• 2017

This study was conducted to propose anti-stigma strategies by verifying the social stigma on behavioral addiction under the premise that social stigma is a main obstacle to the treatment of addiction. A research model was constructed by applying the attribution affection theory and the modified attribution affection theory, which are very useful for explaining emotional and behavioral responses to the persons with mental illness. In other words, when attributing the causes of behavioral addiction to the personally controllable things such as personality, will and lifestyle, social distance can be increased by the mediate of anger. However, when attributing the causes of behavioral addiction to biological factors that can not be controlled by an individual, there can exist two pathway, one is the arising of helping behaviors by the mediate of sympathy (the attribution affection theory), and the other is the aggravation in the social distance due to rising fear (the modified attribution affection theory). In order to verify the research model, 383 adult subjects mainly in South Gyeongsang Province were randomly presented with the vignettes of gambling addiction and internet game addiction, and asked about the causes of the problems and their emotional, prejudicial, and behavioral responses to them. As a result, all pathway had statistically significant predictive effect. Therefore, in the case of attributing to personal causes, social distance increased by the mediate of anger. In the case of attributing to biological causes, both pathway had significant predictive effect, but the indirect effect of the pathway predictive of the helping behavior by the mediate of sympathy was greater. Researchers suggested that anti-stigma strategies, which emphasize that behavioral addiction is a mental health problem requiring treatment, are necessary.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.1
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• pp.15-21
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• 2011

In the range-based localization, the localization accuracy will be high dependent on the accuracy of distance measurement between two nodes. The received signal strength(RSS) is one of the simplest methods of distance measurement, and can be easily implemented in a ranging-based method. However, a RSS-based localization scheme has few problems. One problem is that the signal in the communication channel is affected by many factors such as fading, shadowing, obstacle, and etc, which makes the error of distance measurement occur and the localization accuracy of sensor node be low. The other problem is that the sensor node estimates its location for itself in most cases of the RSS-based localization schemes, which makes the sensor network life time be reduced due to the battery limit of sensor nodes. Since beacon nodes usually have more resources than sensor nodes in terms of computation ability and battery, the beacon node based localization scheme can expand the life time of the sensor network. In this paper, therefore we propose a beacon node based localization algorithm using received signal strength(RSS) and path loss calibration in order to overcome the aforementioned problems. Through simulations, we prove the efficiency of the proposed scheme.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.20 no.1
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• pp.63-72
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• 2010

RFID is one of useful identification technology in ubiquitous environments which can be a replacement of bar code. RFID is basically consisted of tag, reader, which is for perception of the tag, and back-end-database for saving the information of tags. Although the usage of mobile readers in cellular phone or PDA increases, related studies are not enough to be secure for practical environments. There are many factors for using mobile leaders, instead of static leaders. In mobile reader environments, before constructing the secure protocol, we must consider these problems: 1) easy to lose the mobile reader 2) hard to keep the connection with back-end-database because of communication obstacle, the limitation of communication range, and so on. To find the solution against those problems, Han et al. suggest RFID mutual authentication protocol without back-end-database environment. However Han et al.'s protocol is able to be traced tag location by using eavesdropping, spoofing, and replay attack. Passive tag based on low cost is required lots of communication unsuitably. Hence, we analyze some vulnerabilities of Han et al.'s protocol and suggest RFID mutual authentication protocol without online back-end-database in aspect of efficiency and security.

• The Journal of Society for e-Business Studies
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• v.8 no.2
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• pp.99-111
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• 2003

By virtue of diverse advantages derived from digital media, eBook is getting started to use. And many market research agencies have predicted that its market will be greatly expanded soon. But against those expectations, copyright-related problems and the difficulties of its accessing inherited from various eBook content formats become an obstacle to its diffusion. The first problems can be solved by DRM technology. And to solve the second problems, each nation has published its own content standard format. But the domestic standards are useful only the domestic level, they still leave the problems in the national level. The variety of content formats has created a demand for mechanisms that allow the exchange of eBook contents. Therefore we study the mapping relations between eBook contents for conversion. To define the mapping relations, first we extract the mapping both between eBook contents and between normal XML documents. From those mappings, we define seven mapping relations and classify them by cardinality. And we analyze the classified relations, which can be generated by automatic, or not. Using these results, we also classify the eBook content conversion as automatic, semi-automatic, and manual. Besides, we provide the conversion templates for mapping relations for automatic generation of conversion scripts. To show the feasibility of conversion templates, we apply them to the eBook content conversion. Experiment shows that our conversion templates generate the conversion scripts properly. We expected that defined mapping relations and conversion templates can be used not only in eBook content conversion , but also in normal XML document conversion.

• Journal of Korean Academy of Nursing Administration
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• v.5 no.2
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• pp.209-224
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• 1999

I have practiced this reserch for the purpose of proposition of basic data for amendment and addition of computer system after I surveyed the degree of abilities and satisfaction on the computerization in nursing\ practice. Subjects were collected from September 1 to September 30, 1998. Study subjects are 151 clinical nurses who are working at university hospital in Chonbuk area. Study instrument consists of 116 questionnaire which was developed by Kim H. K(1998). The data were analized number, mean ,t-test, ANOVA by using SPSS. The study results are as follows: 1. Most of the nurses who answered the questions were educated computerizing(96%). The abilities of computer program utilities were the most in inputting data(74%). The program nurses wanted computerizing education was wordprocess, dealing internet and statistics. 2. As for applying parts of computer system in nursing, the most nurses were Dr's order check (96%), treatment activity(91.4%), medication(89.4%), lab. test(87 .4%), transfering department(85.4%), transfering room(79.5%), diet(71.8%), discharge (70.2%), Barcord Sticker(70.2%) , reservation(62.2%) in order that were all conected order system mutually to other part. It showed that computer system was not applied for treating the original nursing work such as nursing record (13%), duty scheduling(6.0%) , nursing process(4.6%) , Q.I(1.3%), nursing research(1.3%), education(1.3%), 3. As for the benefit when computer system is applied for, the most respondence was promptness of work and convenience(90.6%) , exactness of work (82.8%), offering information exactily and efficiently(36.3%), offering good quality of nursing (6.0%) in order. 4. The degree of contentment on computerizing in nursing practice showed average 3.24%. The best marking item is that they are eager to participate in the computer education. Next, the automatic output of label and giving the number automatically is to prevent loss and mentioned items of patient registration from being changed(3.95) and to prevent mistakes possibly happening because of doctor's difficult order(3.85). 5. The problems which may happen to in nurses' utilization of computerization for the nursing practice showed average 3.18. The most problem is that the practice may stop because of the problem of computer itself(3.67), and the next, the indication of act can be imperfect(3.66) , manual training may overlap because of incomplete computerization (3.60), practical education for the computerizing is lack(3.41), and the computer literate nurses are lack(3.40) . 6. Study subject's contentment by age was significant difference(F=3.10,P=0.0119). Study subject's contentment by job posision was significant difference(F=6.001P=0.0034) I will propose the following according to the above results. The domain of original nursing practice is urgernt. Manual and indication of act should be made before long in computer obstacle. Nursing department should support the nurses so that they could receive the education needed for the nurses themselves.