• Journal of KIISE
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• v.44 no.5
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• pp.460-468
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• 2017

In a real-time cloud environment, the data analysis framework plays a pivotal role. Spark Streaming meets most real-time requirements among existing frameworks. However, the framework does not meet the second scale real-time fault recovery requirement. Spark Streaming fault recovery time increases in proportion to the transformation history length called lineage. This is because it recovers the last state data based on the cumulative lineage recorded during normal operation. Therefore, fault recovery time is not bounded within a limited time. In addition, it is impossible to achieve a second-scale fault recovery time because it costs tens of seconds to read initial state data from fault-tolerant storage. In this paper, we propose two techniques to solve the problems mentioned above. We apply the proposed techniques to Spark Streaming 1.6.2. Experimental results show that the fault recovery time is bounded and the average fault recovery time is reduced by up to 41.57%.

• Journal of Digital Convergence
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• v.13 no.12
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• pp.319-324
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• 2015

This paper proposes an integrated management system for products of game software development. Those products generated over software life-cycle are generally huge in numbers, various in kinds and interconnected in relationships among them. Especially they are highly complex and tightly coupled each other because they are used to build another world which is composed of multi-modal data such as graphics, sound, logics and so on. Therefore it is critical to manage development products in an integrated manner to guarantee the quality of software. The proposed system is designed to provide project/requirement/configuration/traceability management capabilities and interfacing to CASE standards. To achieve the objective, it is based on data warehouse technologies which provide central repositories of heterogeneous data, multi-aspect reporting&analysis capabilities, traceability, verification, etc.

• Journal of the military operations research society of Korea
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• v.36 no.3
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• pp.69-81
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• 2010

Since the mid-nineties, Republic of Korean Army has officially adapted information technology. Starting with the Chang-Jo 21('99) training M&S Model, around seventy types of the M&S system software, including Ground Operations & Resources Requirement Analysis Model ('10), developed by Republic of Korea Army or foreign counterparts have been utilized. However, as the existing cost estimations of the Defense M&S system software fail to reflect the acquisition and development environment, the estimated costs have been frequently overestimated or underestimated. This paper provides a suitable cost estimation model for the Defense M&S system software by presenting the software cost drivers which reflect the unique software development environment of the Defense.

• The KIPS Transactions:PartC
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• v.8C no.1
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• pp.51-59
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• 2001

In order to support various QoS, IETF has proposed the Differentiated Services Model which provides discrimination service according to t the user’s requirements and payment intention intention for each traffic characteristic. This model is an excellent mechanism, which is not too c complicated in terms of the management for service and network model. Also, it has scalability that satisfies the requirement of Differentiated Services. In this paper, We define the Differentiated Services Model using feedback control, propose its control procedure, and analyze its p performance. In conventional model, non-adaptive traffic, such as UDP traffic, is more occupied the network resource than adaptive traffic, such a as TCP traffic. On the other hand, the Differentiated Services Model using feedback control fairly utlizes the network resources and even p prevents congestion occurrence due to its ability of congestion expectation.

• The KIPS Transactions:PartC
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• v.17C no.3
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• pp.299-306
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• 2010

IPTV and VoIP services are considered as killer applications over Mobile WiMAX network, which provideshigh mobility and data rate. Among those which affect the quality of voice in those services, the jitter buffer or playout buffer can compensate the poor voice quality caused by the packet drop due to frequent route change or differences among routes between service endpoints. In this paper, we analyze the correlation between the sleep interval length and jitter buffer size in order to guarantee a predefined level of voice quality. For this purpose, we present an end-to-end delay model considering additional delay incurred by the WiMAX PSC-II sleep mode and a VoIP service quality requirement based on the delay constraints. Through extensive simulation experiments, we also show that the increase of jitter buffer size may degrade the voice quality since it can introduce additional packet drop in the jitter buffer under WiMAX power saving mode.

• Journal of KIISE:Software and Applications
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• v.34 no.12
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• pp.1021-1036
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• 2007

As the requirement of Semantic Web and knowledge management has been rising, ontology developments have been carried out actively. Ontology is now at the point that systematic developing standardization should be made up like the developing a large scale software. Yet, It has not been made to optimize and standardize ontology development methodologies. In this study, to compare ontology development methodologies, METHONTOLOGY, CommonKADS, OTK in foreign countries and EOE in Korea are selected. The evaluating method is to introduce CMM-I version 1.1 framework. Ontology development methodologies have been evaluated in process areas that introduce for CMM-I maturity level 2 and 3. The purpose of this study is to find matured process and weak process in ontology development methodology on the view of process maturity, and suggests the areas to be Improved in it. The result of this study can be applied as basic data to establish and improve ontology development methodology.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.5
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• pp.617-621
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• 2006

Recently the numbers of the Thai swamp buffalo (Bubalus bubalis), a native species of Thailand, have been rapidly declining, leading to a requirement for conservation programs for this breed. Such studies of the genetic diversity of this species are essential for conservation decisions and to assist the rational implementation of breeding programs. In this study, the genetic diversity of 80 Thai swamp buffalo, randomly selected from seven different research stations of the Thai Department of Livestock Development, were studied using ten cattle microsatellite markers. Polymorphic PCR products were observed at all microsatellite loci, with percentages of polymorphic loci ranging from 80.00 to 100.00%. The population from Payao showed the lowest level of polymorphism. The mean number of alleles per locus was 4.7 with the highest number of alleles being eight (ETH152) and the lowest being three (HAUT27 and ILSTS030). The average unbiased heterozygosity for all seven populations was 0.61 and varied between 0.5314 (Samui) and 0.6798 (Surin). The genetic distance according to NEI's (1972) ranged from 0.0722 to 0.4427. The populations from Surin and Burirum are the closest populations, while populations from Samui and Payao are the most divergent. The information generated by this study will greatly aid in the establishment of effective breeding and conservation programs for the Thai swamp buffalo.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.12
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• pp.6060-6070
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• 2012

Real-Time Enterprise (RTE)'s key requirement is that it should respond and adapt fast to the change of the firms' internal and external situations including the change of market and customers' needs. Recently, the big data processing technology to support the speedy change of the firms is spotlighted. Under the circumstances that wire and wireless communication networks are evolving with an accelerated rate, it is especially critical to provide a strong security monitoring function and stable services through a real-time processing of massive communication data traffic. By applying the big data processing technology based on a cloud computing architecture, this paper solves the managerial problems of telecommunication service providers and discusses how to operate the network management system effectively.

• Journal of Satellite, Information and Communications
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• v.10 no.3
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• pp.131-136
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• 2015

In this paper, prior to the flight model X-band dual-mode circular cavity filter required for the high power transmission of the observation payload in the geostationary satellite, the development model are designed and analyzed to show the analytical multipactor requirement margin. First of all, the multipaction breakdown power sensitivities were analyzed by changing the iris width and thickness within the filter, and through that the iris width and thickness was selected and then the multipaction threshold powers over the frequencies within the bandwidth were analyzed and the required margin of 8 dB was obtained. Also for the high power transmission filter, another important phenomena known as corona breakdown are analyzed for the iris width and thickness changes. Finally the development model manufactured was tested and the results met the key requirements.

• The Journal of the Korea Contents Association
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• v.16 no.5
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• pp.651-659
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• 2016

The purposes of this study is to investigate the influence of career recognition upon career development competencies and educational needs. To achieve this, the survey was carried out and 362 undergraduates participated. The findings of the survey were shown as follows: First, the students perceived that career management was needed the most, and then came career information searches. Next, career transition technologies, positive self-concept formation, career planning, and effective interpersonal relationships were in order. Second, the influence of career recognition upon the level of the preparations showed statistically significant differences, however, the influence of career recognition upon the level of the requirement did not reveal statistically significant differences. Third, the rating of the educational needs was identical from the first place to the third, but different from the fourth to the sixth. These results will contribute to enhancing the efficiency of career education.