• Journal of Digital Convergence
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• v.18 no.6
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• pp.451-457
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• 2020

In this study, the degree of motion sickness displayed according to actions in virtual reality is measured based on the SSQ tool, a measuring tool, and factors and symptoms affecting cyber motion sickness are investigated through comparative analysis. In the first experiment, the operation method experiment, the simple operation method is measured to be highly affected by the Nausea factor. As symptoms of this, nausea, burp and headache symptoms were developed. In the second experiment, the larger the body rotation radius, the higher the motion sickness was measured, and the greater the influence of Nausea factors. Symptoms of this were the symptoms of burping, headaches, and a full head. In the third experiment, the physical mobility experiment, motion sickness was measured highly in the non-action controller. It was measured to be greatly affected by the Nausea factor. Symptoms of this include fever, headache, and a full head. Through this study, we found that the more fixed and simple the body is operated in virtual reality, the more sensitive the user is to motion sickness, and the larger the radius of rotation, the more sensitive it is to motion sickness. This study is meaningful in identifying factors and symptoms that affect motion sickness and VR manipulation, and is expected to be used by developers in the future to recognize the degree and symptoms of motion sickness of users and to develop content.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.44 no.3
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• pp.48-60
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• 2007

In previous researches for iris feature extraction, they transform a original iris image into rectangular one by stretching and interpolation, which causes the distortion of iris patterns. Consequently, it reduce iris recognition accuracy. So we are propose the method that extracts iris feature by using polar coordinates without distortion of iris patterns. Our proposed method has three strengths compared with previous researches. First, we extract iris feature directly from polar coordinate circular iris image. Though it requires a little more processing time, there is no degradation of accuracy for iris recognition and we compares the recognition performance of polar coordinate to rectangular type using by Hamming Distance, Cosine Distance and Euclidean Distance. Second, in general, the center position of pupil is different from that of iris due to camera angle, head position and gaze direction of user. So, we propose the method of iris feature detection based on polar coordinate circular iris region, which uses pupil and iris position and radius at the same time. Third, we overcome override point from iris patterns by using polar coordinates circular method. each overlapped point would be extracted from the same position of iris region. To overcome such problem, we modify Gabor filter's size and frequency on first track in order to consider low frequency iris patterns caused by overlapped points. Experimental results showed that EER is 0.29%, d' is 5,9 and EER is 0.16%, d' is 6,4 in case of using conventional rectangular image and proposed method, respectively.

• The Journal of Society for e-Business Studies
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• v.20 no.1
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• pp.99-115
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• 2015

This study aims to classify the pursuit benefits of smart-phone users, to find smart-phone market segments by pursuit benefits, and to analyze the relative importances of smart-phone attributes according to the smart-phone market segments. As a result, we found that smart-phone users are pursuing the network benefit as well as the two traditional benefits (the utilitarian benefit and the hedonic benefit). According to the levels of these three pursuit benefits, smart-phone users can be classified into four segments : All Benefits Cluster, Utilitarian-Network Benefits Cluster, Hedonic-Network Benefits Cluster, and Non-Network Benefits Cluster. We also verified that, according to the four smart-phone user segments by the pursuit benefits, there exist significant differences in relative importances of the seven smart-phone attributes : hand-set price, hand-set brand, hand-set speed, applications, tariff, mobile internet quality, and number of same service users.

• Microbiology and Biotechnology Letters
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• v.43 no.3
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• pp.296-299
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• 2015

Cowpea mild mottle virus (CPMMV) has a wide range of hosts, such as the pea family and tomato. CPMMV is a non-reported virus in Korea, and is domestically designated as a controlled virus associated with plant quarantine. In this study, a rapid diagnostic method for the detection of CPMMV at quarantine sites was developed. For the development of a user-based system, the PCR compositions and conditions use existing methods of quarantine for the viruses. Two sets of RT-PCR and nested PCR were developed in this study that could be amplified from 579 → 298 dp and 638 → 252 bp, respectively. Furthermore, a sequence inserted positive control plasmid was developed, which is able to identify false-positives resulting from laboratory contamination. The findings of this study are important for the diagnosis of CPMMV in imported crops held in plant quarantine.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.4
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• pp.897-905
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• 2015

This research suggested the traffic signal calculation model of active transit signal priority using a shockwave model. Using this signal priority timing optimization model, the shockwave area is computed under the condition of Early Green and Green Extension among active transit signal priority techniques. This study suggested the speed estimation method of backward shockwave using average travel time and intersection passing time. A shockwave area change is calculated according to signal timing change of transit signal priority. Moreover, this signal timing calculation model could determine the optimal signal priority timings to minimize intersection delay of general vehicles. A micro simulation analysis using VISSIM and its user application model ComInterface was applied. This study checked that this model could calculate the signal timings to minimize intersection delay considering saturation condition of traffic flow. In case studies using an isolated intersection, this study checked that this model could improve general vehicle delay of more over ten percentage as compared with equality reduction strategy of non-priority phases. Recently, transit priority facilities are spreading such as tram, BRT and median bus lane in Korea. This research has an important significance in that the proposed priority model is a new methodology that improve operation efficiency of signal intersection.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.1
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• pp.213-221
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• 2014

Since 2005, when "The Mobility Enhancement for the Mobility Impaired Act" was enacted, special transport systems(SPS) has been introduced by each responsible local entity. For its efficient operations and service enhancements, a clear understanding of travel patterns of SPS users is required. Yet we currently have a very limited understanding about them due to a lack of necessary data. This study represents an attempt to provide a better understanding of SPS user's travel patterns with the data generated by Gyeongsangnam-do SPS Call Center. The data include the number, time and day of calls, origins and destinations of callers, types of callers' impairement etc. The data thus allow one to analyze users' travel patterns, including area-wide O-D patterns. There were a number of interesting findings. For example, wheelchair users are only about 42% and the trips are made mostly on non-peak daytime periods. The results are expected to provide a helpful information not just for Center's SPS operations, but for other local entities that are interested in developing similar call centers as well. By refining the SPS system, periodic patterns of callers could be identified in the future.

• Journal of the Korean Society for Library and Information Science
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• v.46 no.2
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• pp.55-82
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• 2012

This study seeks to develop a curriculum operating model for Korean Library and Information Science, based on investigations into LIS curricula at home and abroad. Standard courses that can be applied to this model were also proposed. This study comprehensively analyzed the contents of domestic and foreign curricula and surveyed current librarians in all types of library fields. As a result, this study proposed required courses, core courses, and elective courses. Six required LIS courses are: Introduction to Library and Information Science, Information Organization, Information Services, Library and Information Center Management, Information Retrieval, and Field Work. Six core LIS courses are: Classification & Cataloging Practice, Subject Information Resources, Collection Development, Digital Library, Introduction to Bibliography, and Introduction to Archive Management. Twenty selective LIS courses include: the General Library and Information Science area (Cultural History of Information, Information Society and Library, Library and Copyright, Research Methods in Library and Information Science), the Information Organization area (Metadata Fundamentals, KORMARC Practice), the Information Services area (Information Literacy Instruction, Reading Guidance, Information User Study), the Library and Information Center Management area (Library Management, including management for different kinds of libraries, Library Information Cooperator, Library Marketing, Non-book Material and Multimedia Management (Contents Management), the Information Science area (Database Management, including Web DB Management, Indexing and Abstracting, Introduction to Information Science, Understanding Information Science, Automated System of Library, Library Information Network), and the Archival Science area (Preservation Management).

• Journal of the Korean Society for Library and Information Science
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• v.42 no.2
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• pp.147-170
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• 2008

Evaluation of an academic library is a key to its success. Library and Information Policy Bureau of the President of the Republic of Korea conducted a trial evaluation on academic libraries with a university evaluation index developed by KERIS in 2005. The committee decided to review its feasibility based on the feedbacks from the academic libraries after the trial. This study aims to address the indexing issues appeared during the trial and suggest a new evaluation index tailored to academic libraries. First, the evaluation field is condensed from 7 to 6 as "financing" and "infrastructure" are integrated into "budget and infrastructure." Secondly, both "user charter" and "planning" are removed from the "library management" field category. and "library self-assessment" is added instead. In "information resource" field, "non-books and etc." is added. Third, evaluation categories for "budget and infrastructure" field are altered to budget-related items and library equipment. Forth, "collection turnover rate" category is incorporated into "collection usage" in "information usage" field, and "library use rate" in "information service" field is moved to "information resource" field and renamed as "use rate."

• Journal of the Korean Institute of Gas
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• v.5 no.1
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• pp.60-72
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• 2001

This paper presents the user-interactive productivity analysis model based on material balance as well as deliverability equations equipped with EOS model to perform a productivity analysis for Gorae V structure, Donghae-1 gas field. This model is designed to be able to analyse the productivity in the case of reservoir contacting with the aquifer. Also, in order to investigate the effect of condensation on productions, condensation phenomenon is considered as an apparent skin effect in the computation of bottomhole pressure from average reservoir pressure. By utilizing the developed model, we investigate the productivity analysis for B2 layer of Garae V structure with the various production cases in volumetric and non­volumetric reservoirs that contact with aquifer. From the results in the case of 5500 MMSCF/year of production and reservoir-aquifer contacting angle 270$^{\circ}C$ with aquifer size of 10 times greater than reservoir, B2 layer could maintain peak production rate even after 8.5 years of production by considering the bottomhole pressure which is estimated above the operating pressure of 1298 psia. It is also found that condensate will be formed after 1100 days of production and existed throughout the reservoir at 1270 days. Note that the computed reservoir pressure of B2 layer is maintained sufficiently high enough for production due to the water influx into the reservoir, and skin effect caused by condensation is not significant.

• Journal of KIISE:Information Networking
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• v.31 no.6
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• pp.582-594
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• 2004

In school PC labs or other educational purpose PC labs with a few dozens of PCs, computers are configured in a distributed architecture so that they are set up, maintained and upgraded separately. As an alternative to the distributed architecture, we can consider a thin-client computing environment. In a thin-client computing environment, client side devices provide mainly I/O functions with user friendly GUI and multimedia processing support whereas remote servers called terminal server provide computing power. In order to support many clients in the environment, a cluster of terminal servers can be configured. In this architecture, it is difficult due to the characteristics of terminal session persistence and different pattern of computing usage of users so that the utilization of terminal server resources becomes low. To overcome this disadvantage, we propose an adaptive terminal cluster where terminal servers ,ire partitioned into groups and a terminal server in a light-loaded group can be dynamically reassigned to a heavy-loaded group at run time. The proposed adaptive scheme is compared with a generic terminal service cluster and a group based non-adaptive terminal server cluster. Experimental results show the effectiveness of the proposed scheme.