• Journal of the Korean Institute of Gas
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• v.27 no.2
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• pp.57-64
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• 2023

As the meter reading method of gas meters develops, smart gas meters capable of remote meter reading (leak checking meters and multi-function safety meters) are being used. These meters have a function to judge leakage by utilizing the flow rate and pressure data collected as an additional function. Leakage judgment function using flow rate data has valid cases in the actual field, but the pressure data-based leakage judgment standard is based on not only the pressure value change due to leakage but also various factors (pressure regulator pressure, connection with adjacent meters, usage of adjacent houses, location of meters, etc.). There is a problem with pressure magnitude changes (levels). In this paper, as a technique that can judge leaks by using pressure data collected from smart gas meters, it was developed through preprocessing of pressure data, criteria for pressure value ranges related to leaks, leak judgment techniques, and application case verification.

• Proceedings of the KIEE Conference
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• 1993.11a
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• pp.9-12
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• 1993

This study investigated the propriety and the extension of the term of validity about the using watthour meters at present. The subject of study is 1Cent 2W 220V 30(10)A, 1Cent 3W 110V 30(10)A of model III watthour meters. They are the used metes(products in 1984) and the repaired meters(products in 1977) in the end of the period. The investigation is as follows. o Investigation of external appearance o Driving current test o Creeping test o Noise test o Error test o Durability test. Results of the study have been the number of 13.3% exceeded permitting error and the number of 31.3% failed in endurable test of 500 hours. So, the using meters are not suitable to extend the term of validity without the improvement of several characteristics.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.379-386
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• 2007

Recently the concrete slab tracks are being constructed on roadbed in the Kyong-bu 2nd stage high speed railways. In responding to this trend, new design standards and track materials maintenance systems, based on the slab track material safety and usage perspective, are needed. This research provides the design standards and the maintenance system. The proposed standards and the maintenance system are based on the track theory and the track-train interaction program developed, where the roadbed displacement and train speed are utilized as mediating variables. In the analysis, the dynamic response of track-train interaction apply to various speeds and displacements. the roadbed displacement is shown in a sine curve, the scope of the displacement occurrence, presented in its wavelenths, include 6meters, 10meters, 15meters, 20meters, 30meters. the train speeds involved are 50,100, 150,200,250,300,350,400 kilometers per hour.

• Journal of Radiation Protection and Research
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• v.44 no.3
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• pp.97-102
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• 2019

Background: Dose rate meters are the most widely used, and perhaps one of the most important tools for the measurement of ionising radiation. They are often the first, or only, device available to a user for an instant check of radiation dose at a certain location. Throughout the world, radiation safety practices rely strongly on the output of these dose rate meters. But how well do we know the quality of their output? Materials and Methods: This review is based on the measurements 1,158 commercially available dose rate meters of 116 different makes and models. Expected versus the displayed dose patterns and consistency was checked at various dose rates between $5{\mu}Gy{\cdot}h^{-1}$ and $2mGy{\cdot}h^{-1}$. Samples of these meters were then selected for further investigation and were exposed to radiation sources covering photon energies from 50 keV to 1.5 MeV. The effect of detector orientation on its reading was also investigated. Rather than focusing on the angular response distribution that is often reported by the manufacturer of the device, this study focussed on the design ergonomics i.e. the angles that the operator will realistically use to measure a dose rate. Results and Discussion: This review shows the scope and boundaries of the ionising radiation dose rate estimations that are made using commonly available meters. Observations showed both inter and intra make and model variations, occasional cases of instrument failure, instrument walk away, and erroneous response. Conclusion: The results indicate the significance of selecting and maintaining suitable monitors for specific applications in radiation safety.

• Journal of Korean Society of Forest Science
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• v.77 no.2
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• pp.235-241
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• 1988

This study was carried out to identify the variation of culm characteristics of Phyllostachys bambusoides associated with attitudinal gradient in Mt. Jiri. The results obtained were summarized as follows : It was estimated that the average temperature at the altitude of 400 meters of Mt. Jiri was $12^{\circ}C$ which was closely associated with the horizontal distributions. It was observed that frequency distribution of the culm height, D.E.H. and clear length from the altitude of 200 meters to 400 meters shown at higher than that from 500 meters to 600 meters, and that frequency of clear length/culm height showed about equal for both altitude ranges. In the case of culm height, D.E.H. and clear length/culm height, coefficients of variation ranged from 15 percent to 25 percent, and those of clear length were over 25 percent for both altitude ranges. It was observed that culm height, D.E.H., clear length and clear length/culm height among each altitude ranges were significant at the 1 percent level. The Duncan's Test of culm characteristics among altitude ranges distinguished bamboos of below 400 meters from bamboos of over 500 meters. The correlation coefficients among culm characteristics of Phyllostachys bambusoides associated with attitudinal gradient were shown to be highly significant. In conclusion, the variation of calm characteristics of Phyllostachys bambusoides was large for below 400 meters and these results suggest that planting of the species should be done below 400 meters.

• Journal of Korean Society of Water and Wastewater
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• v.19 no.4
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• pp.506-514
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• 2005

Unaccounted-for water subtracting water sold from produced water includes leakage, under-registration, unauthorized use, etc. To improve accounted-for water ratio, firstly, it should be attempted to accurately identify where unaccounted-for water is, and then it must to be reduced. Under-registration of meter is caused by allowable tolerance of meter, improper size of meter installed, gradient installation, etc. Under-registered water of meters has ever been the second large amount of unaccounted-for water next to leakage, but still is not estimated exactly. In this study, the estimated value as under-registered water was obtained by using the selected-area modeling program. As a result, the under-registered water ratio of 13mm meters was approximately 1.23%. Those of meters according to ages 1, 3, and, 5 years old were 1.46% 2.77% and, 2.26%, respectively but that of 7 years old meters showed over-registration of 1.59%.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.741-746
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• 2003

The foundation of Noksan area is composed of consolidified sediments including clay mineral, quartz, plagioclase and calcite. The mineral compositions vary dependent on the depth. That is, at the depth of 0-15 meters quartz and plagioclase are more abundant than clay mineral, at the depth of 17-39 meters clay minerals and calcite are more than quartz and plagioclase, at the depth deeper than 40 meters, the amounts of quartz and plagioclase increase slightly and that of clay minerals decrease. Clay minerals of the clayey sediments include illite, smectite, kaolinite and chlorite. At the depth 17-39 meters smectite is abundant and kaolinite is little relatively The pH of suspension is various between 3-9 and decrease to 3-5 at the depth deeper than 40 meters. The result of soil test of clay sediments, water content shows that liquid limit, plastic limit, particle size, unconfined compressive strength varies depending on the depth. The variation of mineralogical, geochemical, engineering properties of soil with the depth are probably due the differing sediments of different sedimentary environment. That is, these variations are considered to be correlated with the sedimentary environment change resulting from the change from continental environment to ocean environment due to the transgression of the interglacial period after the regression the latest glacial period.

• Korean Journal of English Language and Linguistics
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• v.1 no.4
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• pp.509-536
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• 2001

The traditional typology of English poetic meters makes a binary division between strong-stress (or accentual) meters and accentual-syllabic (or syllable-stress or syllable-accent) meters. According to this typology, Old and Middle English alliterative poetry was composed in strong-stress meter; the iambic pentameter from Chaucer to Yeats and on to the present has been an accentual-syllabic meter. Intersecting with this literary typology is a linguistic typology that classifies languages of the world as stress-timed or syllable-timed or some mix of the two. English is a clear example of a stress-timed language. Whereas most descriptions of strong-stress meter focus on the counting of stresses, the present study focuses on the patterns of unstressed syllables between the stresses (possibly at isochronous intervals). The implications of this analysis suggest a new typology in which certain forms of English verse follow strict grammatical stress (mainly Old and Middle English, but for reasons different from “strong-stress” expectations) and other forms are shaped by a compromise of grammatical stress and the metrical template. Within this later group, iambic pentameter contrasts with trochaic, anapestic, and dipodic meters in lending itself more readily to modulation. Some of this modulation comes from an easy incorporation into iambic pentameter of elements associated with Old and Middle English meters.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.04a
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• pp.207-211
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• 2005

The Korean Tilting Train eXpress (TTX) with service speed of 180km/h have been developing using hybrid design concept combined with a sandwich composite structure for the carbody and stainless steel structure for the underframe to match the challenging demands with respect to cost efficient lightweight design for railway carriage structures. The sandwich composite structure was used to minimize the weight of the carbody, while the metal underframe was used to modify the design easily and to keep the strength of underframe for the installation of the electrical equipments. The sandwich composite structure was 23 meters long, 3 meters wide and 2.7 meters high, and cured as one body in a large autoclave equipment with the length of 30 meters and the diameter of 5 meters. The joint part between the carbody structure made of sandwich composites and the metal underframe was joined by the proposed design.

• Proceedings of the KIEE Conference
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• 2001.07a
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• pp.308-310
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• 2001

With the development of Computer & Communication Technology, nowadays many people are interested in remote metering, and many vendors are suggesting various remote metering solutions. KEPCO (Korea Electric Power Corporation) adopts some of these to some customers who uses a lot of electric power, also continues researching them. But, currently used electronic watt-hour meters vary in terms of communication protocol and data structure by the vendors. So we have to know each vendor's communication protocol and data structure to construct a remote metering system, or to find problems in it. But that's impossible to know each vendor's protocol and data structure because they are reluctant to tell those to outside the company. To solve these problems and to make a much more cost-effective metering system, KEPCO developed standard communication protocol between meters and PC (or metering server), and defined standard functions and data structure which can be used by everyone easily. Those developments support standard interface for every vendors' meters. And Those will be adopted by KEPCO for a part of a new metering standard for electronic watt-hour meters.