• Journal of the Korea Society of Computer and Information
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• v.20 no.10
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• pp.91-97
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• 2015

In this paper, we propose a MCFQ I/O scheduler that is implemented by modifying the existing Linux CFQ I/O scheduler. MCFQ observes whether the user requested I/O bandwidth weight is well distributed. Based on the I/O bandwidth observation, we improved I/O performance of the existing bandwidth distribution ability by dynamically controlling the I/O time-slice of the virtual machine. The use of SSDs as storage has been increasing dramatically in recent computer systems due to their fast performance and low power usage. As the usage of SSD increases and prices fall, virtualized system administrators can take advantage of SSDs. However, studies on guaranteeing SLA(Service Level Agreement) services when multiple virtual machines share the SSD is still incomplete. In this paper was conducted to improve performance of the bandwidth distribution when multiple virtual machine are sharing a single SSD storage in a virtualized environment. In particular, it was observed that the performance of the bandwidth distribution varied widely when garbage collection occurs in the SSD. In order to reduce performance variance, we add a MoTS(Manager of Time Slice) on existing CFQ I/O scheduler.

• Journal of Creative Information Culture
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• v.6 no.2
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• pp.101-106
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• 2020

In preparing for future education, the need for software education is increasing. In addition to the content of operation, the assessment portion issues have emerged as an important area in software education. In this study, we wanted to look at the effectiveness of the learner-led assessment in software education through literature research and consider what this suggests to the schooling. According to a study conducted on software education for elementary school students, the student-led assessment showed significant effects on the improvement of students' creativity, problem solving, information literacy, and increased interests in software education. Further research efforts are requested to help the schooling prepare for future education through student-led software assessment.

• KIPS Transactions on Software and Data Engineering
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• v.5 no.11
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• pp.593-606
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• 2016

Computer simulation is widely used in a variety of computational science and engineering fields, including computational fluid dynamics, nano physics, computational chemistry, structural dynamics, and computer-aided optimal design, to simulate the behavior of a system. As the demand for the accuracy and complexity of the simulation grows, however, the cost of executing the simulation is rapidly increasing. It, therefore, is very important to lower the total execution time of the simulation especially when that simulation makes a huge number of repetitions with varying values of input parameters. In this paper we develop a simulation service system that provides the ability to predict the result of the requested simulation without actual execution for that simulation: by recording and then returning previously obtained or predicted results of that simulation. To achieve the goal of avoiding repetitive simulation, the system provides two main functionalities: (1) storing simulation-result records into database and (2) predicting from the database the result of a requested simulation using statistical machine learning techniques. In our experiments we evaluate the prediction performance of the system using real airfoil simulation result data. Our system on average showed a very low error rate at a minimum of 0.9% for a certain output variable. Using the system any user can receive the predicted outcome of her simulation promptly without actually running it, which would otherwise impose a heavy burden on computing and storage resources.

• Journal of the Daesoon Academy of Sciences
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• v.24_2
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• pp.85-115
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• 2015

The Reordering of the Universe(天地公事) pursuing the Latter world(後天)'s ideal world while denying the Former world(先天) is composed of enormous rituals. The Dosu(度數) is formed through these rituals and the world is transformed according to the Dosu. The people who follow the Sangje(上帝), the subject of this universe reordering and also participate in the Reordering of the Universe are called as the followers. The follower group can be said as a ritual group in the aspect that they participate in the ritual for the Reordering of the Universe. They not only observed the rituals but also actively participated in them, so took certain roles in forming the Dosu. That is, they performed certain, given roles in developing the rituals, or actively proposed their ideas under the Sangje's leadership, and participated in the process realizing the Dosu. Therefore it can be said that they were a group initiatively participating in the process overcoming the Former world's Sangguk(相克) world, and making the latter world's ideal world. It seemed that the followers at that time might have gone through a certain entrance ritual process in order to join in such a follower group. The 『Jeon-Gyeong』 recorded the entrance rituals of a man called as Cha Gyeong Seok among tremendous followers relatively in detail. According to the 『Jeon-Gyeong』, he first had to get a unique test in the entrance process, and the test was proceeded in several stages: the wisdom test reflecting the Sangje's unusual intelligence, the patience test to endure physical, psychological pains for the great ethic, and the test to evaluate the testee's ability to give up past oneself and to follow the Sangje with a new body & mind. In the process separating himself from the past his appearance, Gyeong-Seok, the candidate to enter, faced a liminal situation, and then performed the incorporation rite. In this process, the purification rite going him out of the past relationship of benefits & grudges was performed, and he was given the regulations to comply as a member of the follower group. Through such serial processes, his entrance in the follower group was allowed. What requested to the candidate in this entrance process was the severance from one's past. For that, the candidate was needed to go out of his past life habits, to free from the relationship of benefits and grudges, and to sever him from his past faults. Such severance was the precondition for him to go out of the Former world's negative reality and to break from the Sanggeuk habits. Another thing requesting to the candidate as well as the severance from his past was to establish a new ideal. The new ideal should be matched with the ideal of the Reordering of the Universe whose main ideology was the Haewon-Sangsaeng(解冤相生). Such ideal can be said as the driving force to proceed toward the new ideal world of Latter World. And the candidate was requested to purify his mind and to participate in the Universe Fair Judgement (天地公庭). That can be said as an important condition for the new member directly to participate in the ritual of the Reordering of the Universe dramatically transforming the world. Finally, the candidate was given the regulations for his ascetic practice(修道) as well as his participation in the Reordering, and was requested to comply them. After becoming a member of this follower group, one had to practice his asceticism through the compliance with such regulations and the training of mantras(呪文) in order to accomplish the goal called as Dotong(道通). By fulfilling these requirements, the newly entered member could have the qualification to perform a certain role in the ritual of the Reordering of the Universe, and could accomplish his religious ideal.

• Analytical Science and Technology
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• v.28 no.6
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• pp.446-452
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• 2015

In order to evaluate and improve the ability of Korean testing laboratories to measure Polybrominated diphenyl ethers in acrylonitrile-butadiene-styrene (ABS), a proficiency test was organised by Korea Research Institute of Standards and Science (KRISS) based on ISO/IEC 17043. The proficiency test material used was 10 g of a granular ABS fortified with a mixture of congeners of PBDE (BDE-154, 183, 206, 209). Homogeneity and stability were investigated to assess the adequacy of the test material. The certified value established by KRISS based on the national reference was used for assigned value of each PBDE. The test materials were distributed to the 16 participating laboratories. The participating laboratories were requested to analyse the samples employing the methods used in their routine analysis. Each laboratory was given it’s own code to secure the anonymity. Participants results were evaluated with z-scores according to ISO/IEC 17043. The standard deviation for proficiency assessment was set by standard deviation of the participants results except for outlier. The results, the laboratory's performance and improvement of accuracy were discussed.

• Archives of design research
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• v.13 no.4
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• pp.23-32
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• 2000

The present age is requested designer to be a generalist. The educational methods of university is changing over from intention of the technical education which is one of the traditional education methods to intention of a talented man with multiple knowledge. Also, the universities are establishing special curricular for cultivating men of ability. Many of an employer want to engage not only the specialist as the talented men in their own major field, but the generalist as the multiple knowledge in several field. Designer should have both a good stock of knowledge and personality. Also design should be able to easy access to all as a generalist instead of an obstinate streak as a monopoly of their specialist. This study was focused on development of basic research for understanding about design to generalist. It is purposed to suggest a research for a new recognition of design.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.10
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• pp.101-107
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• 2007

In order to introduce remote monitoring system for effective safety management of electrical facilities for general use, which the most of electrical fires and non-inspection problems due to absence are generated development of local device model considering cost and installation is requested. This paper presents local device models for remote electrical safety inspection of electrical facilities for general use and in order to rational model according to installation place of electrical facilities for general use, compare and analysis cost, installation and communication method of local device models. The results show that rational model for remote safety inspection of electrical facilities located in houses, which occupy the must of electrical facilities for general use, is to give safety monitoring ability to low voltage remote meter reading(or automatic meter reading: AMR).

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.9
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• pp.1985-1992
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• 2011

PE(Passive Entry) is an automotive technology which allows a driver to lock and unlock door of vehicle without using smart key buttons personally. PG(Pssive Go) is an automotive technology which offers the ability to start and stop the engine when there is a driver in vehicle with smart key. When these two functions are unified, we call it PEG(Passive Entry/Go). LF(Low Frequency) antenna driver which is one of core technologies in PEG is composed of a digital part which processes commands and an analog part which generates sine waveform. The digital part of antenna driver receives commands from MCU(or ECU), and processes requested commands by MCU, and stores antenna-related driver commands and data on an internal FIFO block. The digital part takes corresponding actions for commands read from FIFO and then transfers modulated LF data to analog part. The analog part generates sine waveform and transmits outside through antenna. The designed digital part for LF antenna driver can acomplish faster LF data transmission than that of conventional product. LF antenna driver can be applicable to the areas such as PEG for automotive and gate opening and closing of building.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.9
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• pp.1286-1293
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• 2014

Typically, studies through the simulation system have been progressed, because the evaluation of the driver's arousal state about the service of a actual train has risk of safety for the driver. When configured event same as the real in simulation system, the ability to cope with an accident situation may be the same each other. But the difference in the state of tension or arousal will occur. In this study, requested to cooperate with the railways in order to escape from these constraints, and the target of the experiment was to real engineer service. I was set about experiment when the train was stopped as safe as possible. As a result, the beta wave of EEG signals that representing complex calculations or anxiety is increased rapidly on the basis of a flag station from at the time of departure. The size of the electrodermal activity signal in response to movement of the body gave a noticeable. In terms of HRV, if the train approach a flag station gradually and the R-R interval is narrowed. So that the driver can be estimated as arousal state. In accordance with this study, if the quantitative standard of arousal state be based on the driver's biosignals will provide, it will be able to take advantage of development the system that would prevent train accidents caused by human error.

• Journal of Advanced Navigation Technology
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• v.20 no.5
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• pp.440-445
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• 2016

There is a scheme where secondary users (SU) use predicted spectrum holes for primary users (PU) not to utilize for efficient utilization of the limited spectrum resources in cognitive radio networks. In this paper, we propose an adaptive call admission control framework that minimizes spectrum hopping call dropped probability (SHDP) for satisfying SU quality of service (QoS). The scheme is based on a call admission control (CAC), bandwidth prediction and adaptive bandwidth assignment. The prediction model predicts not only the number of spectrum holes, but requested bandwidth of SU spectrum hopping call, and then the CAC minimizes SHDP via an adaptive bandwidth assignment in resources not being enough for reservation. We bring Wiener prediction model to predict the resources. Simulations are conducted to compare the performance of proposed scheme with an existing, and show its ability of minimizing the SHDP.