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pISSN : 1598-849X / eISSN : 2383-9945

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2018, Vol.23, No.3

  • 1.

    Recency and Frequency based Page Management on Hybrid Main Memory

    Kim Sungho , Kwak, Jong Wook | 2018, 23(3) | pp.1~8 | number of Cited : 0
    Abstract PDF
    In this paper, we propose a new page replacement policy using recency and frequency on hybrid main memory. The proposal has two features. First, when a page fault occurs in the main memory, the proposal allocates it to DRAM, regardless of operation types such as read or write. The page allocated by the page fault is likely to be high probability of re-reference in the near future. Our allocation can reduce the frequency of write operations in PCM. Second, if the write operations are frequently performed on pages of PCM, the pages are migrated from PCM to DRAM. Otherwise, the pages are maintained in PCM, to reduce the number of unnecessary page migrations from PCM. In our experiments, the proposal reduced the number of page migrations from PCM about 32.12% on average and reduced the number of write operations in PCM about 44.64% on average, compared to CLOCK-DWF. Moreover, the proposal reduced the energy consumption about 15.61%, and 3.04%, compared to other page replacement policies.
  • 2.

    A study on Automatic field Test Equipment with improved maintenance and environmental reliability

    Seok-Min Lee | 2018, 23(3) | pp.9~16 | number of Cited : 1
    Abstract PDF
    In this paper, I purpose one of the development methods for portable Automatic field Test Equipment(ATE) with VME form factor. Almost portable ATE have not used to standards form factor and they are connected by mechanical non-rigid general connectors and wire harnesses among the components. Furthermore, it is hard to reuse developed board. So, it decreases to reusability of developed board and it is hard to maintenance of ATE. Even those things have weakness for vibration and drop test especially in portable ATE. The XK9A1 ATE using VME form factor has environmental reliability through vibration, drop, temperature test. It consists of 5 developed board called the control board, the wire & wireless communication board, the power supply board, the load board and the mother board. It is connected by two wire harnesses between mother board and extern circular connectors. The control board send the data and address to other board though each 16-bit data and 20-bit address line. You can develop the function board what you want to using those data & address line when it comes to needing other function board.
  • 3.

    Automatic Detection of the Middle Tooth Crown Part for Full Automatic Tooth Segmentation in Dental CT Images

    Chan-Woo Lee , Oksam Chae | 2018, 23(3) | pp.17~23 | number of Cited : 0
    Abstract PDF
    In this paper, we propose the automatic detection method which find the middle part of tooth crown to start individual tooth segmentation. There have been many studies on the automation of individual tooth segmentation, but there are still many problems for full automation. Detection of middle part of tooth crown used as initial information for individual tooth segmentation is closely related to performance, but most studies are based on the assumption that they are already known or they can be represented by using a straight line. In this study, we have found that the jawbone curve is similar to the tooth alignment curve by spatially analyzing the CT image, and propose a method to automatically detect the middle part of tooth crown. The proposed method successfully uses the jawbone curves to successfully create a tooth alignment curve that is difficult to detect. As the middle part of tooth crown is in the form of a tooth alignment curve, the proposed method detects the middle part of tooth crown successfully. It has also been verified by experiments that the proposed method works well on real dental CT images.
  • 4.

    D2D Power Control in the Cellular System: Non Cooperative Game Theoretic Approach

    Oh Chang Yoon | 2018, 23(3) | pp.25~31 | number of Cited : 0
    Abstract PDF
    In this paper, we consider the game theoretic approach to investigate the transmit power optimization problem where D2D users share the uplink of the cellular system. Especially, we formulate the transmit power optimization problem as a non cooperative power control game. In the user wide sense, each user may try to select its transmit power level so as to maximize its utility in a selfish way. In the system wide, the transmit power levels of all users eventually converge to the unique point, called Nash Equilibrium. We first formulate the transmit power optimization problem as a non cooperative power control game. Next, we examine the existence of Nash Equilibrium. Finally, we present the numerical example that shows the convergence to the unique transmit power level.
  • 5.

    Effective adjacent baggage split method of Baggage Position Control System to prevent double loading of baggage

    Jaewon Song , Dong-Chul Kim | 2018, 23(3) | pp.33~40 | number of Cited : 0
    Abstract PDF
    In this paper, we propose a method to effectively split the adjacent baggage that is moving on high speed conveyor of airport. The proposed method calculate the Angle Histogram(AH) that inspects background pixels within radius r based on the center point of the adjacent baggage. After that, the adjacent baggage is segmented by finding split angles at the AH. We also improved the split quality of adjoining baggage by repeatedly correcting the center point to correctly split adjacent baggage of asymmetric size. And the calculation time of AH is reduced about 1/3 by using the symmetry property of the circle. Experiments have shown that 93% of all adjacent baggage images are correctly segmented and the proposed method is effective.
  • 6.

    Development of the Unified Database Design Methodology for Big Data Applications - based on MongoDB -

    Jun-Ho Lee , Joo Kyung-Soo | 2018, 23(3) | pp.41~48 | number of Cited : 1
    Abstract PDF
    The recent sudden increase of big data has characteristics such as continuous generation of data, large amount, and unstructured format. The existing relational database technologies are inadequate to handle such big data due to the limited processing speed and the significant storage expansion cost. Current implemented solutions are mainly based on relational database that are no longer adapted to these data volume. NoSQL solutions allow us to consider new approaches for data warehousing, especially from the multidimensional data management point of view. In this paper, we develop and propose the integrated design methodology based on MongoDB for big data applications. The proposed methodology is more scalable than the existing methodology, so it is easy to handle big data.
  • 7.

    Development of the Design Methodology for Large-scale Data Warehouse based on MongoDB

    Jun-Ho Lee , Joo Kyung-Soo | 2018, 23(3) | pp.49~54 | number of Cited : 0
    Abstract PDF
    A data warehouse is a system that collectively manages and integrates data of a company. And provides the basis for decision making for management strategy. Nowadays, analysis data volumes are reaching critical size challenging traditional data ware housing approaches. Current implemented solutions are mainly based on relational database that are no longer adapted to these data volume. NoSQL solutions allow us to consider new approaches for data warehousing, especially from the multidimensional data management point of view. In this paper, we extend the data warehouse design methodology based on relational database using star schema, and have developed a consistent design methodology from information requirement analysis to data warehouse construction for large scale data warehouse construction based on MongoDB, one of NoSQL.
  • 8.

    Crowdfunding Scams: The Profiles and Language of Deceivers

    Lee seunghun , Hyun-chul Kim | 2018, 23(3) | pp.55~62 | number of Cited : 0
    Abstract PDF
    In this paper, we propose a model to detect crowdfunding scams, which have been reportedly occurring over the last several years, based on their project information and linguistic features. To this end, we first collect and analyze crowdfunding scam projects, and then reveal which specific project-related information and linguistic features are particularly useful in distinguishing scam projects from non-scams. Our proposed model built with the selected features and Random Forest machine learning algorithm can successfully detect scam campaigns with 84.46% accuracy.
  • 9.

    Long-term Driving Data Analysis of Hybrid Electric Vehicle

    Jiyoung Woo , Yang In Beom | 2018, 23(3) | pp.63~70 | number of Cited : 0
    Abstract PDF
    In this work, we analyze the relationship between the accumulated mileage of hybrid electric vehicle(HEV) and the data provided from vehicle parts. Data were collected while traveling over 70,000 Km in various paths. The data collected in seconds are aggregated for 10 minutes and characterized in terms of centrality, variability, normality, and so on. We examined whether the statistical properties of vehicle parts are different for each cumulative mileage interval of a hybrid car. When the cumulative mileage interval is categorized into =< 30,000, <= 50,000, and >50,000, the statistical properties are classified by the mileage interval as 82.3% accuracy. This indicates that if the data of the vehicle parts is collected by operating the hybrid vehicle for 10 minutes, the cumulative mileage interval of the vehicle can be estimated. This makes it possible to detect the abnormality of the vehicle part relative to the accumulated mileage. It can be used to detect abnormal aging of vehicle parts and to inform maintenance necessity.
  • 10.

    Effects of Elastic Band Resistance Training on Muscle Strength among Community-Dwelling Older Adults: A Systematic Review and Meta-Analysis

    Young-Ran Yeun | 2018, 23(3) | pp.71~77 | number of Cited : 1
    Abstract PDF
    The purpose of this study was to investigate the effectiveness of elastic band resistance training for muscle strength among community-dwelling older adults. The systematic review and meta-analysis was conducted by following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). Data were pooled using fixed effect models. Sit to stand, arm curl, and grip strength were analyzed for main effects. Heterogeneity between studies was assessed using the I2 statistics and publication bias was evaluated by funnel plots. Twelves studies were included representing 611 participants. Elastic band resistance training was effective for lower (d=3.89, 95% CI: 3.03, 4.75) and upper extremity muscle strength (d=4.08, 95% CI: 2.94, 5.23). Heterogeneity was moderate and no significant publication bias was detected. Based on these findings, there is clear evidence that elastic band resistance training has significant positive effects on muscle strength among community-dwelling older adults. Further study will be needed to perform subgroup analysis using number of sessions and exercise intensity as predictors.
  • 11.

    Comparative Analysis of Dental Hygiene Course Students' NCS Learning Goals before and after NCS Class

    Hee-Sun Woo | 2018, 23(3) | pp.79~84 | number of Cited : 2
    Abstract PDF
    The government developed National Competency Standards and expands field friendly education for innovation of industrial field based education training. NCS is the national level of standards that the government systemized knowledge, skills and attitudes required to work in industrial fields by each industry and each level. This study was intended to research NCS education contents of an introduction of dental hygienics, which is a basic major subject among subjects of dental hygiene course, to present learning goals accordingly, and to be used as a basic resource of NCS field oriented classes of dental hygienists through the comparison before and after. In case of the dental hygiene course, dental hygienists are performing important core tasks as clinicians at dental offices. Therefore, such comprehensive and professional performance abilities as scaling, oral prophylaxis and oral health education are required at the fields. The education process and education contents for this should be researched continuously.
  • 12.

    A time-cost tradeoff problem with multiple interim assessments under the precedence graph with two chains in parallel

    Choi Byung-Cheon , Yunhong Min | 2018, 23(3) | pp.85~92 | number of Cited : 0
    Abstract PDF
    We consider a project scheduling problem in which the jobs can be compressed by using additional resource to meet the corresponding due dates, referred to as a time-cost tradeoff problem. The project consists of two independent subprojects of which precedence graph is a chain. The due dates of jobs constituting the project can be interpreted as the multiple assessments in the life of project. The penalty cost occurs from the tardiness of the job, while it may be avoided through the compression of some jobs which requires an additional cost. The objective is to find the amount of compression that minimizes the total tardy penalty and compression costs. Firstly, we show that the problem can be decomposed into several subproblems whose number is bounded by the polynomial function in , where  is the total number of jobs. Then, we prove that the problem can be solved in polynomial time by developing the efficient approach to obtain an optimal schedule for each subproblem.
  • 13.

    Study on the Civil Legal Remedies against Cyber Defamation

    Park, Jong-Ryeol | 2018, 23(3) | pp.93~100 | number of Cited : 0
    Abstract PDF
    Cyber defamation is the act of damaging the reputation of the other person on the Internet, and the act of attacking by the commenting the article through a word or blog. The reason why punishment is stronger than general contempt is that the nature of crime about defamation is worse than contempt. Also, punishment intensity is higher than defamation because the nature of cyber information spreads widely. Honor is not only a question of self-esteem or identity, but also a function that economically reduces the cost of seeking information or socially trustworthy. Through these two functions, it has been developed as a legal system to protect the honor as well as asking the legal sanction for defamation. However, although honor is used in various meanings in everyday life, the honor of legal level is understood in a more limited sense. It is because the law cannot actively lead and protect all honor feelings for one's feelings or mood occurred by hurt. However, if the social evaluation of a group or individual is undermined through a certain distortion of the truth, the law will actively intervene. However, due to the ambiguity of the legal sanctions standards and the identification of the parties involved in the defamation of cyberspace, it was difficult to solve the problems related to defamation in fact. Therefore, this paper will try to find out the problems of civil legal remedy due to the cyber defamation, and seek a solution for civil legal remedy.
  • 14.

    A Study on Relationship between Smartphone User Pattern and Addiction

    Myung-Suk Lee , Lim, Young Kyu | 2018, 23(3) | pp.101~106 | number of Cited : 0
    Abstract PDF
    The purpose of this study is to analyze the patterns of unconsciousness smartphone use by using an app and a self-administered survey on smartphone addiction comparatively and examine differences between recognition and behavior about actual smartphone use and examine how smartphone addiction influences learning. With an app installed in smartphones, this author collected and analyzed data about users’ unconsciousness using patterns for a month. According to the results, there were significant differences found in users’ recognition and actual time for use and also frequency of turning on the display. Also, 22% of the subjects used their smartphone over 8 hours a day, and 76% more than 5 hours. Over 95% turned on the display more than 100 times a day, and in extreme cases, they did more than 300 times. In the meantime, users not only in the smartphone addiction high risk group and the potential risk group but also in the general user group are found to use their smartphone too long and too much and frequently turn on the display. The apps that the general user group is mainly using are entertaining apps, and their school records are rather good, so excessive use does not always lead to addiction or learning disorder. Therefore, if we develop more diverse contents for learning and provide digital literacy education, smartphone use will bring more positive effects instead. In follow-up research, the app should be corrected to collect more accurate information, and as variables in personal areas, this researcher will also measure depression, anxiety, stress, self-esteem, and emotional control, and so on to see how they are associated with smartphone use.
  • 15.

    The Effect of Self-leadership and Entrepreneurship on Employment Competency -The Moderating Effect of Nationality-

    Ju Cheol Choi | 2018, 23(3) | pp.107~115 | number of Cited : 2
    Abstract PDF
    This study aimed to explore the effect of college students’ self-leadership and entrepreneurship on employment competency and identify the moderating effect of nationality. To this end, the validity of data collected from 450 college students attending a four-year university in Seoul was tested using structural equation modeling and AMOS statistical software. The study showed the following results. First, self-leadership was found to have a significant effect on entrepreneurship. Second, entrepreneurship was found to have a significantly positive effect on employment competency. Third, it was found that nationality exerted a partial effect on the relationship of self-leadership and entrepreneurship to employment competency. Based on these findings, this study indicated that developing college student’s employment competency through self-leadership and entrepreneurship training according to their nationality can help resolve the severe employment crisis in the age of the fourth industry.