• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.2
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• pp.1180-1200
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• 2017

Currently, automated payment services provide intuitive user interfaces by adapting various wireless communication devices with mobile services. For example, companies like Samsung, Google, and Apple have selected the NFC payment method to service payments of existing credit cards. An electronic payment standard has been released for NFC activation within Korea and will strengthen the safety of payment service communications. However, there are various security risks regarding the NFC-based electronic payment method. In particular, the NFC payment service using the recently released lightweight devices cannot provide the cryptographic strength that is supported by many financial transaction services. This is largely due to its computational complexity and large storage resource requirements. The chaotic map introduced in this study can generate a highly complicated code as it is sensitive to the initial conditions. As the lightweight study using the chaotic map has been actively carried out in recent years, associated authentication techniques of the lightweight environment have been released. If applied with a chaotic map, a high level of cryptographic strength can be achieved that can provide more functions than simple XOR operations or HASH functions. Further, this technique can be used by financial transaction services. This study proposes a mutual authentication technique for NFC-PCM to support an NFC payment service environment based on the chaotic map.

• Journal of the Korean Association of Geographic Information Studies
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• v.24 no.4
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• pp.174-183
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• 2021

This study aims to suggest a method to provide a real-time noise map based on cloud using Amazon AWS. Acquiring environmental noise information, an Android app was developed to collect data on noise level, location, and measurement time of campus in Inha Technical College as a study area. Noise measurement information is transmitted to the AWS Cloud and managed, and the noise information collected through Amazon Quick Site is displayed in charts and maps. Finally, a web-based noise contour map and the results mapped to buildings were visualized with a Google map for users to search for the current environmental noise distribution. The real-time noise map presented as a result of this study is expected to be helpful for noise status and reduction policies.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.23 no.2
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• pp.99-104
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• 2013

Assessment of noise exposed population is to check the environmental noise level and social influence in order to reduce the risks such as annoyance and disturbance that are generated by environmental noise. Also, this method suggests the preferential noise abatement policy and action plan by accurately finding the area that the noise causes harmful effect to human health. Recently, a noise map, which can predict noise in comprehensive areas, is used for the assessment of noise exposed population, breaking from the methods using existing measures. In particular, countermeasure for the noise can be considered more effectively by using assessment methods of noise exposed population for specific noise levels, areas, and building types which are the main input factors in noise maps. In this study, assessment methods of noise exposed population by using 2 dimensional noise map are compared with those by 3 dimensional noise map.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.1
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• pp.150-157
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• 2004

For the mobile GIS services, it is not acceptable to construct a new map database only for wireless service due to vast cost. But the existing map database cannot be used directly for the services due to narrow wireless bandwidth and shortage of mobile device resources. This thesis proposes spatial data simplification methods, thus, the existing map database enable the mobile GIS services. The proposing methods are based on the existing map generalization techniques. We extend it to mobile environments, and implement. This thesis also includes the issue of discriminative data simplification technique according to display level and map display interface suitable for mobile devices. Research results an estimated by experiments.

• Genomics & Informatics
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• v.9 no.3
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• pp.136-137
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• 2011

Methylation of cytosine is a post-synthesis modification that does not affect the primary DNA sequence but greatly influences gene expression level and phenotypes of an organism. As high-throughput sequencing of bisulfite-treated DNA is the most efficient method to identify methylated sites, several tools to map sequencing reads on a reference are available. But tools to visualize and to interpret the methylation level of methylation sites are currently insufficient. Herein, we present a novel tool to visualize the methylation level of CpG sites.

• Sleep Medicine and Psychophysiology
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• v.7 no.1
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• pp.18-26
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• 2000

Objectives: To investigate the airway narrowing patterns by multi-level airway pressure(MAP) monitoring during sleep and to evaluate the value of CT scan taken during waking and sleep apneic periods to identify the level of airway narrowing(LAN) in patients with obstructive sleep apnea syndrome(OSAS). Methods: Eleven patients with OSAS underwent a night polysomnography with continuous MAP monitoring by 4-sensor(placed at nasopharynx, caudal-uvula, hypopharynx, esophagus) or 2-sensor(placed at caudal-uvula and esophagus) catheter. All patients had cine CT at five levels of high retro and alatal, low retropalatal, retroglossal, epiglottis and hypopharynx during awake and sleep periods. In each patient, LAN determined by CT scan($LAN_{CT}$) during sleep apnea was compared with LAN by MAP monitoring($LAN_{MAP}$). Results: MAP monitoring showed that four patients(36%) had a single pattern of LAN while the other seven patients(64%) showed two or more different LANs in different apneic episodes. Velopharynx was the most common level of frequently observed airway narrowing during sleep apnea(63.6%). However, a single pattern of airway narrowing was more frequent(72.7%) in airway CT during sleep apnea. Velopharynx was the most common narrowest level also in apneic CT(66%). In comparing $LAN_{CT}$ with $LAN_{MAP}$, the $LAN_{CT}$ of five patients(45.5%) were high-concordant, those of another five(45.5%) low-concordant, and that of one(9%) discordant with $LAN_{MAP}$. Conclusions: Cine CT scan during the awake state or sleep apnea may not reflect the LAN correctly in OSAS because most patients showed two or more different airway narrowing patterns during different episodes of sleep apnea in each patient.

• Food Science of Animal Resources
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• v.30 no.4
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• pp.685-694
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• 2010

The present study investigated the combined effects of modified atmosphere packaging (MAP) and organic acid salts on the quality and shelf-life of Hanwoo ground beef patties. The ground beef containing 500 ppm of ascorbic acid was prepared with air-packaging (Air-P), high oxygen-MAP (70% $O_2$+30% $CO_2$/OxyMAP), and nitrogen-MAP (100% $N_2$/NitroMAP), in combination with organic acid salts (1500 ppm of sodium acetate and 500 ppm of calcium lactate). The samples were stored for 11 d at $5^{\circ}C$. The pH value of ground beef patties decreased during storage in all the treatments. The ground beef patties with organic acid salts showed relatively higher level of pH during storage compared with non-added patties (p<0.05). Lipid oxidation was accelerated in OxyMAP while it was delayed in NitroMAP treated with organic acid salts. Nitro-MAP treated with organic acid salts was effective in stabilizing the color characteristics of lightness (CIE $L^*$) and redness (CIE $a^*$) during storage. Oxygen content in MAP was shown to be a more important factor affecting color stability and lipid oxidation of ground beef than organic acid salts. The aerobic and anaerobic bacterial counts were reduced both in OxyMAP and NitroMAP (p<0.05), and the lactic acid bacteria was inhibited by Oxy-MAP (p<0.05). Coliform bacteria decreased during storage as pH value was decreased in all treatments. According to the sensory evaluation, the ground beef patties in NitroMAP showed the best quality among all treatments during storage. Therefore, Hanwoo ground beef patties added with sodium acetate and calcium lactate and packed with NitroMAP showed better quality characteristics than other treatments. This packaging method is recommended and could be utilized for packaging hanwoo ground beef patties for improving quality and extending shelf-life.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.8
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• pp.1511-1513
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• 2007

A new reference point location method using the cosine component is proposed, where an edge map is defined and used to find the reference point. Because all processes used in the proposed method are performed at the block level, less processing time is required. Experimental results show that the proposed method can effectively detect the reference point with higher speed and accuracy for all types of fingerprints.

• Journal of Intelligence and Information Systems
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• v.27 no.4
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• pp.49-71
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• 2021

Users who intend to utilize knowledge to actively solve given problems proceed their jobs with cross- and sequential exploration of associated knowledge related each other in terms of certain criteria, such as content relevance. A knowledge map is the diagram or taxonomy overviewing status of currently managed knowledge in a knowledge-base, and supports users' knowledge exploration based on certain relationships between knowledge. A knowledge map, therefore, must be expressed in a networked form by linking related knowledge based on certain types of relationships, and should be implemented by deploying proper technologies or tools specialized in defining and inferring them. To meet this end, this study suggests a methodology for developing the knowledge graph-based knowledge map using the Graph DB known to exhibit proper functionality in expressing and inferring relationships between entities and their relationships stored in a knowledge-base. Procedures of the proposed methodology are modeling graph data, creating nodes, properties, relationships, and composing knowledge networks by combining identified links between knowledge. Among various Graph DBs, the Neo4j is used in this study for its high credibility and applicability through wide and various application cases. To examine the validity of the proposed methodology, a knowledge graph-based knowledge map is implemented deploying the Graph DB, and a performance comparison test is performed, by applying previous research's data to check whether this study's knowledge map can yield the same level of performance as the previous one did. Previous research's case is concerned with building a process-based knowledge map using the ontology technology, which identifies links between related knowledge based on the sequences of tasks producing or being activated by knowledge. In other words, since a task not only is activated by knowledge as an input but also produces knowledge as an output, input and output knowledge are linked as a flow by the task. Also since a business process is composed of affiliated tasks to fulfill the purpose of the process, the knowledge networks within a business process can be concluded by the sequences of the tasks composing the process. Therefore, using the Neo4j, considered process, task, and knowledge as well as the relationships among them are defined as nodes and relationships so that knowledge links can be identified based on the sequences of tasks. The resultant knowledge network by aggregating identified knowledge links is the knowledge map equipping functionality as a knowledge graph, and therefore its performance needs to be tested whether it meets the level of previous research's validation results. The performance test examines two aspects, the correctness of knowledge links and the possibility of inferring new types of knowledge: the former is examined using 7 questions, and the latter is checked by extracting two new-typed knowledge. As a result, the knowledge map constructed through the proposed methodology has showed the same level of performance as the previous one, and processed knowledge definition as well as knowledge relationship inference in a more efficient manner. Furthermore, comparing to the previous research's ontology-based approach, this study's Graph DB-based approach has also showed more beneficial functionality in intensively managing only the knowledge of interest, dynamically defining knowledge and relationships by reflecting various meanings from situations to purposes, agilely inferring knowledge and relationships through Cypher-based query, and easily creating a new relationship by aggregating existing ones, etc. This study's artifacts can be applied to implement the user-friendly function of knowledge exploration reflecting user's cognitive process toward associated knowledge, and can further underpin the development of an intelligent knowledge-base expanding autonomously through the discovery of new knowledge and their relationships by inference. This study, moreover than these, has an instant effect on implementing the networked knowledge map essential to satisfying contemporary users eagerly excavating the way to find proper knowledge to use.

• Journal of The Korean Association For Science Education
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• v.36 no.2
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• pp.295-302
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• 2016

In this study, we investigated a learning progression focusing on $5^{th}$ to $9^{th}$ graders' performances with dissolution and solution concepts using the construct modeling approach. We designed a construct map describing hypothetical pathways of the concept development of dissolution and solution by analyzing both National Science Curricula and related studies. A conceptions test consisting of ordered multiple-choice items was developed and administered to 826 students. A revised construct map was derived from analyses of the results based on the partial credit model, a branch of polytomous item response theory. The sequence of dissolution and solution concepts presented in the current science curriculum was found to correspond with the learning progression of the students. However, the lower anchor, the concept of the homogeneity of particles in solution, and the factors affecting solubility were not consistent with the expected levels of the construct map. After revising the construct map, we proposed a learning progression for dissolution and solution concepts with five levels: Students of level 1 (the lower anchor) recognize the particles in the solution but misunderstand various concepts; Students of level 2 understand the homogeneity of particles in solution; Students of level 3 understand solubility and the conservation of particles during dissolution; Students of level 4 partially understand the interaction between particles; and Students of level 5 (the upper anchor) understand the interaction between particles and the factors affecting solubility.