• Aerospace Engineering and Technology
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• v.11 no.2
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• pp.39-48
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• 2012

In case a measurement output of gyro sensor is an accumulated angle counts, it is usually provided as a binary bit counter which is allowed to roll-over at its maximum or minimum value. And it is a well known fact that the roll-over behavior restricts the measurement range of the processed sensor output below the actual measurable range of sensor hardware itself. In this study, a conventional sensor data processing method for a gyro with an accumulated angle output is introduced. And also, an improved method which can extend the processed output range over the conventional one is proposed. It is also derived that the increased range depends on the variation speed of a input signal. Finally, the derived equations and the performance of the proposed algorithm are verified using a computer simulation.

• Journal of the Korean Data and Information Science Society
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• v.27 no.1
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• pp.75-89
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• 2016

This study suggests both modification reserve ratio and cover rate for expenditure as new finance evaluation indicators. Firstly, modification reserve ratio is an evaluation indicator which shows how long can the accumulated reserves at the beginning of the year afford future benefit expenditure. Modification reserve ratio has an advantage both to present what the scale of annual accumulated reserves means and to know the exhaustion speed of accumulated fund through analyzing the trend of modification fund ratio. Secondly, this research classifies resources for expenditures as premium income and reserves, thereafter, presents cover rate for expenditure as finance evaluation indicator. We can know how premium income and reserves can cover future expenditure during the evaluation period, and how deficient are resources through these indices. The researcher anticipates this research to contribute to policy researches for financial stabilization of the national pension scheme.

• Journal of Korean Society of Forest Science
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• v.96 no.2
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• pp.170-177
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• 2007

The objectives of this study were to select early, late, and abundant flowering trees of black locust from domesticated and introduced cultivars, and prediction of flowering period by calculation of accumulated temperature in spring. Four cultivars (Debreceni-2, Pusztavacs, Jaszkiseri, and Rozsaszin AC) from Hungary and a cultivar from Beijing, China, were introduced, propagated by seed and planted in a seed orchard. For domesticated black locust, 63 cultivars from 10 locations throughout the country were selected and propagated by root cutting. Criteria for selection of domesticated cultivars were abundant flowering, long flowering period, or abundant nectar production with, if possible, straight stems. Accumulated temperature was calculated from data of a nearby weather station by accumulating daily maximum temperature minus 5 degree Celsius from January 1 up to the date reaching 880 degrees. Daily mean temperature was also used to calculate accumulated temperature up to the date reaching 450 degrees. The percentages of two-year and three-year-old flowering trees propagated by root cutting were higher than that of trees propagated by seeds, while four-year-old trees all flowered regardless of propagation methods. Among the domesticated cultivars, all the cultivars from Ganghwa showed abundant flowering with highest nectar production of 6.5 ul per flower, which was 100% more than other domesticated cultivars and 50% more than Debreceni-2 cultivar with highest nectar production among the introduced cultivars from Hungary. At the end of the eight years of observations, two trees of Debreceni-2 cultivars and a tree from Beijing, China were selected for early flowering trees which flowered 2 to 3 days earlier than average trees, while a tree of Debeceni-2 and three trees from Bejing were selected for late flowering trees which flowered 2 to 3 days later than average trees. It is possible to extend the flowering period of black locust by 4 to 6 days by planting early and late flowering cultivars together. Abundant flowering trees were unable to be selected due to severe damages by leaf gall midges which killed many trees and reduced the crown size of the remaining trees in the seed orchard, and which were first found in Korea in 2001 and now damaging most of the black locust forests in Korea. The prediction of flowering period by accumulated temperature indicated that black locust flowered to a peak when accumulated daily maximum temperature reached 880 degrees Celsius, and when daily mean temperature reached 450 degrees.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.6
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• pp.315-325
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• 2016

Due to the expansion of data and technical progress in the military industry, it is important to extract meaningful information for assuring quality and making policies. The analysis of trends and decision making based on big data is helpful for increasing productivity in business and finding new business opportunities. We propose an application to collect reliable quality information for munitions and build a big data platform for using the accumulated information and numerical data. We verified the proposed platform using the Test Report Information Service (TRIS) system and suggest a method that utilizes unstructured and semi-structured data accumulated by TRIS. Thus, we expect that the proposed platform will help in building infrastructure for military data, making efficient strategies, and analyzing trends for assuring munitions quality.

• Journal of Korea Water Resources Association
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• v.40 no.8
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• pp.643-654
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• 2007

This study proposes and evaluates a methodology for deriving the rainfall intensity- duration-frequency relationship for durations less than 10 minutes used for designing drainage systems in small urban catchments and roads. The method proposed in this study is based on the Moupfouma distribution, which has been evaluated by applying it to the rainfall data at the meteorological Seoul station. Summarizing the results is as follows: (1) The frequency analysis results using minutely rainfall data was found not to be corresponded with the extrapolation of that by the Ministry of Construction and Transportation (2000). (2) The annual maxima minutely rainfall data derived by applying the Moupfouma distribution to the accumulated 60-minute data was found to well reproduce the characteristics of those of observed. (3) The rainfall intensity-duration-frequency relationship derived by applying the Moufouma distribution to the accumulated 50-minute data and hourly data was found insignificant.

• Journal of Digital Contents Society
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• v.17 no.5
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• pp.409-416
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• 2016

Recently, Big Data issue has become a buzzword and universities, industries and research institutes have been efforts to collect, analyze various data enabled. These things includes accumulated data from the past, even if it is not possible to analysis at this present immediately a which has the potential means. And we are obtained a valuable result from the collected a large amount of data via the semantic analysis. The demand for high-performance storage system that can handle large amounts of data required is increasing around the world. In addition, it must provide a distributed parallel file system that stability to multiple users too perform a variety of analyzes at the same time by connecting a large amount of the accumulated data In this study, we identify the I/O bandwidth of the storage system to be considered, and performance of the metadata in order to provide a file system in stability and propose a method for configuring the optimal environment.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.8
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• pp.845-850
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• 2009

Localization which estimates a robot's position and orientation in a given environment is very important for mobile robot navigation. Although low-cost sensors are preferred for practical service robots, they suffer from the inaccurate and insufficient range information. This paper proposes a novel approach to increasing the success rate of low-cost sensor-based localization. In this paper, both the previous and the current data obtained from the IR sensors are used for localization in order to utilize as much environment information as possible without increasing the number of sensors. The sensor model used in the monte carlo localization (MCL) is modified so that the accumulated range information may be used to increase the accuracy in estimating the current robot pose. The experimental results show that the proposed method can robustly estimate the robot's pose in indoor environments with several similar places.

• Journal of Technologic Dentistry
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• v.16 no.1
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• pp.105-113
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• 1994

This study attempted to find out how much stress Dental Technicians of working in Dental Laboratory have built up in the midst of their daily lives are according to their sex, age, duration of work and their kinds of positions. After self-administered questionnaire were distributed by direct to 230 technicians samplely selected from dental laboratories in Seoul and Pusan of whom 163 technicians responded from october 1 through october 13, 1994. Analysis of the data was processed by t-test, $X^2$-test, ANOVA. This results are as follows. 1. Levels of Stress of the total 163 respondents by sex is not higher among male than female(p>.05). 2. Levels of stress - 36.2%(74 Dental technicians) of all Dental technicians were in stress on the whole and 9.2%(15 Dental technicians) of them were in a serious situation by accumulated stress. 3. Realization of stress - 10.1%(16 Dental technicians) of the dental technicians and 89.9%(143 Dental technicians) were found out to be in a dangerous sign or in a situation by accumulated stress. Further studies which a big size and a delicate method of measuring their general characteristics are needed.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.2
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• pp.315-319
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• 2011

A switched-capacitor cyclic DAC scheme with mismatch compensation of capacitors is designed. In cyclic DAC, a little error between two capacitors is accumulated every cycle. As a result, the accumulated error influences the final analog output which is wrong data. Therefore, a mismatch compensation technique was proposed and the error can be effectively reduced, which alleviates the matching requirement. In order to verify the operation of the proposed DAC, an 8-bit switched-capacitor cyclic DAC is designed through HSPICE simulation and implemented through magna 0.18um standard CMOS process.

• Journal of the Society of Disaster Information
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• v.1 no.1
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• pp.121-136
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• 2005

Most human-error case of accident database is written by various description and expression because accident database is produced by two or more person. And extracted information by searching of database varies in researcher's judgment criteria and the capability. Furthermore, much time and effort are required to examine manually information related to the human error from each accident case. Accordingly, it is difficult to explore objectively the accidents relevant to the human-error from the accident data base which is accumulated enormously. In this study, to solve these problems, it was developed an searchig method which is not influenced by researcher's judgment criteria and capability. For this, human-error keywords were extracted from a Japanese-English dictionary to examine objectively the accident case related to human-error in data base. This searching method by the human-error keywords can be applicable in most accident databases, although a database will be accumulated in future. Also, using the searching technique of this research, knowledge obtained by searching result can be compared with other research's results by the same method. Although the number of accident case increasese, searching results from database have the objectivity because it is not necessary to modify the based searching method or change the human-error keywords. However, as subject of future investigation, it would be necessary that the extension and investigation on human-error keywords improve and the technique to enhance searching accuracy would be modified.