• The KIPS Transactions:PartA
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• v.11A no.5
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• pp.355-364
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• 2004

These days, various clustering technologies have been adopted to construct web sites. High performance hardware switches have good performance, but have disadvantage of high cost for constructing small and middle-sized web sites. Now a days, many sites have been constructed with the LVS (Linux Virtual Server), which is free of charge and has good performance. Having a centralized load balancing with one front-end, the LVS causes a bottleneck when it receives all at once. In the paper, we suggest a way to remove the LVS bottleneck by providing multiple front-ends. In this architecture, all of cluster nodes act as both a front-end and a back-end. When the load of a node receiving requests is not large enough, the node responds to the client directly. When the load of a node is large enough, the node send the request to a node which is selected by a scheduling algorithm. The scheduling algorithm is discussed to balance loads between servers. While single front-end cluster raises the throughput curvedly, the multiple front-end cluster raises the throughput linearly.

• The Journal of the Convergence on Culture Technology
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• v.9 no.1
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• pp.697-702
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• 2023

Recently, with the introduction of drones, a core technology of the 4th industrial revolution, various convergence education using drones is being conducted in school education sites. In particular, drone theory and practice education is being conducted in connection with free semester classes and career exploration. The drone convergence education program has higher learner satisfaction than simple demonstration and practice education, and the learning effect is high due to direct practical experience. However, since practical education is being conducted for a large number of learners, it is impossible to restrict and control the flight of a large number of drones in a limited place. In this paper, we propose a monitoring system that allows the instructor to monitor multiple drones in real time and learners to recognize collisions between drones in advance when multiple drones are operated, focusing on education operated in schools. The communication module used in the experiment was equipped with GPS in Murata LoRa, and the server and client were configured to enable monitoring based on the location data received in real time. The performance of the proposed system was evaluated in an open space, and it was confirmed that the communication signal was good up to a distance of about 120m. In other words, it was confirmed that 25 educational drones can be controlled within a range of 240m and the instructor can monitor them.

• Journal of Internet Computing and Services
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• v.14 no.1
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• pp.53-62
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• 2013

It is common among users to have multiple computing devices as well as to access their files or do work at different locations. To achieve file consistency as well as mobility in this scenario, an efficient approach for workspace synchronization should be used. However, file synchronization alone cannot guarantee the mobility of work environment which allows activities to be resumed at any place and time. This paper proposes a ubiquitous synchronization approach which provides cloud-based access to a user's workspace. Efficient synchronization is achieved by combining session monitoring with file system management. Experimental results show that the proposed mechanism outperforms Cloud Master-replica Synchronization in terms of number of I/O operations, CPU utilization, as well as the average and maximum latencies in responding to client requests.

• Journal of Digital Contents Society
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• v.9 no.2
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• pp.295-303
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• 2008

With universality of e-commerce through internet, smaller online shopping malls are increased. A Smaller online shopping mall by nature lacks an extra space to load many inventory quantities. Therefore, it is difficult to response immediately with client request with traditional inventory management method. VMI has a character that supplier can control volume of inventory according to sales of seller. This paper proposes SOHO-VMI that is applied VMI into smaller online shopping mall. Proposed SOHO-VMI supports M $\times$ N structure can interact with multiple suppliers and sellers. And it uses XML/EDI for interaction with EDI documents use to legacy system. Also, This paper proposes logistics statistic prediction algorithm can adjust production and distribution volumes to supplier considering seller's product distribution information and seasonal factor.

• Journal of Korean Academy of Nursing Administration
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• v.2 no.1
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• pp.73-96
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• 1996

In the complexity and diversity of modern society, there is an urgent need for an information system which can systematically collect, manage and analyze data. Especially in the discipline of nursing, a nursing informarion system is necessary to maximize nursing resources and improve nursing care in the present system which is faced with increases in client needs and multiple changes in hospital environments. This research was done to provide a basis for the development of an integrative nursing information system for the future, by designing dababases items which were extracted from an analysis of the ward nursing information system on general wards excluding the OPD, ICU, OR and CSR with functions using a different system from the wards, and the design of output screen used the database items. The ward nursing information system was analysed through analysis of nursing practice related to recordings, such as the worksheet, kardex, and other nursing practice recordings, on 25 wards. The development of the database was the part of the construction of hospital information system and used the database development life cycle which is related to the system development life cycle. The database development steps included selection of database management system and design of a physical database following the principles of the order communication system which is been developing at Y University Hospital. Conceptual database and Logical database were designed using the base of 25 data items and fields derived from analysing the worksheet, the data items and fields derived from the kardex and other nursing practice recording, from these 19 data base tables were framed through transforming the relational database. Through this process, four types of output material for nursing practice recording which nurses can carry and use during their nursing practice were produced.

• Journal of Korea Multimedia Society
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• v.14 no.7
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• pp.849-857
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• 2011

Gaming on demand(GOD) makes people enjoy games by encoding and transmitting game screen at a server side, and decoding the video at a client side. In this paper, we propose a fast game video encoder for multiple users over network with low-powered devices. In the proposed system, the computational complexity of game encoders is reduced by using scene descriptors, which consists of an object motion vector, global motion, and scene change. With additional information from game engines, the proposed encoder does not need to perform various complexity processes such as motion estimation and ratedistortion optimization. The motion estimation and rate-distortion optimization skipped by scene descriptors. We found that the proposed method improved 192 % in terms of FPS, compared with x264 software. With partial assembly code, we also improved coding speed by 86 % in terms of FPS. We found that the proposed fast encoder could encode over 60 FPS for real-time GOD applications.

• The Journal of the Korea Contents Association
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• v.15 no.11
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• pp.115-125
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• 2015

This study was to identify major risk factors associated with secondary traumatic stress in a sample of 654 public social welfare specialists. Findings indicated that 69.0% of the subjects experienced secondary traumatic stress, and 36.9% of them were in a high-risk group. Multiple regression analysis showed that the risk of the secondary traumatic stress was associated with gender, work hours, physical violence and threats from clients, coping strategies, and vocational self-efficacy. Based on these results, several interventions for preventing the incidence of secondary traumatic stress among public social welfare specialists are suggested as the follows: construction of secure job environment, development of educational programs for improving vocational self-efficacy and coping skills, and implementation of mental health screening system on a regular basis to prevent the outbreak of mental disease among the workers.

• The KIPS Transactions:PartB
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• v.8B no.5
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• pp.507-514
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• 2001

In VOD(Video-on-Demand) system, the real-time interactive service is one of the most important factor to determine the degree of QoS(Quality of Service). In this paper, we propose the head-end system consisted of switching agent and head-end node, which needs to receive the only video stream for multiple users which have requested the same video, to serve the unlimited interactive service which has no service delay and block. The unlimited VCR services can be served by storing the video stream with buffer at client and head-end node. And the proposed algorithm presents the method to enhance the efficiency by buffer, offer the true interactive VOD services to users because all of service requested by clients are processed immediately. In this paper, we implemented the VOD system which has the VCR functions without service delay and block. Simulation results indicate that the proposed algorithm has better performance in the number of service request and time interval.

• Korean Journal of Occupational Health Nursing
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• v.27 no.2
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• pp.109-120
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• 2018

Purpose: The aims of this study were to examine the work, client, and personal environments of community health practitioners, including the level of their professional quality of life (ProQOL), and identify the factors affecting their ProQOL. Methods: Data were collected using a web-survey questionnaire, which was completed by a sample of 308 community health practitioners currently working in Korea. The questionnaire included items on ProQOL; three dimensions labeled compassion satisfaction, burn out, and secondary traumatic stress; job stress; job satisfaction; sense of community; and general characteristics. Results: The mean scores for the three dimensions were $39.2{\pm}6.44$ (compassion satisfaction), $31.9{\pm}3.59$ (burn out), and $26.4{\pm}5.05$ (secondary traumatic stress). A multiple linear regression revealed that compassion satisfaction varied significantly according to the satisfaction with job choice, sense of community, job stress, and job satisfaction. The factors affecting burn out were sense of community and work load, while the factors affecting secondary traumatic stress were education, job stress, and job satisfaction. Conclusion: The findings of this study suggest that comprehensive intervention focusing on improving the sense of community and job satisfaction and reducing job stress is essential to promote community health practitioners' ProQOL.

• Phonetics and Speech Sciences
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• v.5 no.4
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• pp.217-225
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• 2013

This paper describes the design and implementation of the kWebAnywhere system based on WebAnywhere, which assists people with severely diminished eye sight and the blind people to access Internet information through Web interfaces. The WebAnywhere is a server-based web reader which reads aloud the web contents using TTS(text-to-speech) technology on the Internet without installing any software on the client's system. The system can be used in general web browsers using a built-in audio function, for blind users who are unable to afford to use a screen reader and for web developers to design web accessibility. However, the WebAnywhere is limited to supporting only a single language and cannot be applied to Korean web contents directly. Thus, in this paper, we modified the WebAnywhere to serve multiple language contents written in both English and Korean texts. The modified WebAnywhere system is called kWebAnywhere to differentiate it with the original system. The kWebAnywhere system is modified to support the Korean TTS system, VoiceText$^{TM}$, and to include user interface to control the parameters of the TTS system. Because the VoiceText$^{TM}$ system does not support the Festival API used in the WebAnywhere, we developed the Festival Wrapper to transform the VoiceText$^{TM}$'s private APIs to the Festival APIs in order to communicate with the WebAnywhere engine. We expect that the developed system can help people with severely diminished eye sight and the blind people to access the internet contents easily.