• Journal of Advanced Marine Engineering and Technology
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• v.38 no.7
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• pp.936-942
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• 2014

As a result of the exhaustion of fossil fuel, interest about renewable energy is increasing day by day. Inter alia, study for wave power energy of which the calculability is high and the available amount is abundant is going along actively. As a float-countweight wave energy converter is equivalent improved structural strength compared with oscillating body type. we made the wave only in order to up and down motion by setting up bulkhead which is called wave camber at the outside of float. This paper mainly focuses on generation amount of plural connected float-counterweight wave energy converter and we calculate the amount. The result, we confirmed that the more a numerical value of nl/L increases, the more amount of electricity rises and also when it is over nl/L=0.40, it is possible to get continuous generation. Through this study, we can use as basic data for design of wave chamber on advantageous condition at the real seas and by way of estimation for generation amount.

• Journal of Applied Reliability
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• v.16 no.3
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• pp.192-201
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• 2016

Purpose: In this paper, we propose the output model of the optimal inventory requirements of the Maintenance Float (M/F). Weapon systems were modernized and increased costs. Thus, the complexity increases with. Alternatives to achieve the goal of availability of weapon systems and to reduce life-cycle cost are required. Especially, securing spare parts is more effective than adding the amount of equipment or maintenance facilities to achieve the goal of availability and reduce life cycle costs. However, securing spare parts and repair costs are directly related, so exact requirements are needed. Methods: Three kinds of methods (Calculation method of applying the Poisson distribution, Calculation method of considering the number of CSP, and Calculation method of applying M&S program) that this paper proposed compare the influence of the availability and the amount of spare parts. Result: We calculate the cost of M/F when the operational availability is over than 80% and compare that result. The biggest cost was calculated from the Poisson distribution method. We found that requirements and unit price is the key factor that gives a significant effect. Conclusion: These three kinds of methods can be used as a basis for Maintenance Float calculation. Among them, the calculation method based on CSP is optimal replacement equipment requirements calculation method.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.10
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• pp.1964-1972
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• 2017

K-water have been operating as an International accredited calibration organization for ISO 17025 regarding float, ultrasonic and radar type since 2008. Due to the absence of on-site calibration system, water level meter could only be calibrated from a laboratory. Therefore K-water institute developed an mobile calibration system for water-level meter in 2015 to calibrate the water-level meter on site. The mobile calibration system was certificated by KOLAS(Korea Laboratory Accreditation Scheme) in 2016. In this paper a mobile calibration system, which is a method to calibrate float type water level meter on site, is established. A mathematical equation was derived by reviewing characteristics of standard equipment and measurement. By developing the mobile calibration system, it is possible to achieve reliability of data through scientific system operation on hydrological data.

• KDI Journal of Economic Policy
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• v.28 no.1
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• pp.193-218
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• 2006

This paper examines the macroeconomic structural differences of the free floating exchange rate regime and the managed float exchange rate regime focusing on the Korean economy, and compares it to the two benchmark economies, Japan and Australia. Korea's shift to the free floating exchange rate regime from the managed float exchange rate regime came after the 1997 economic crisis. Korea's exchange rate policy provides a unique opportunity to study the different behaviors or roles, if any, of managed float and free floating exchange rate regimes. Based on a simple monetary model, we find that the exchange rates of Korea are more sensitive to the economic fundamentals under the free floating regime than under the managed float regime. Impulse response analysis shows that exchange rate pass-through into domestic variables, especially inflation rate, has a bigger short-term impact under the floating regime than under the managed regime. This finding is consistent with the view that the managed (or fixed) regime provides the domestic price stability necessary for the economic growth for the developing countries.

• Journal of the Korean Society of Costume
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• v.56 no.9 s.109
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• pp.37-49
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• 2006

The purpose of this study is to figure out the types and characteristics of the twill damask fabrics through literatures review of both domestic and Chinese documents and records. In addition, the study aims to review the characteristics of the twill damask fabrics found at Sukga Pagoda. The twill damask fabrics can be categorized in terms of the weaving method into Float Pattern on a Tabby Ground, Twill Pattern on a Tabby Ground, Float Pattern on a Twill Ground, Twill Pattern on a Twill Ground, and Without Pattern on a Twill Ground. The fabrics ran also be divided in terms of their name into Ki, Neung, and Munju. Four items of twill damask fabrics were found inside the Sukga Pagoda. All of them are Twill Pattern on a Twill Ground. At the primitive level of weaving skill, twill damask fabric was made by adding patterns with twill damask or BuJik on the background of plain weave. At more advanced level, the fabrics are weaved by making patterns with twill damask or BuJik on the background of twill damask. Compared to the relics of Koryo and Chosun Dynasty, these twill damask fabrics were loosely weaved with relatively thick thread.

• Journal of the Korea Fashion and Costume Design Association
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• v.24 no.2
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• pp.1-10
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• 2022

The purpose of this study is to analyze the structural properties of 100% wool fabrics knitted with various stitch types and to evaluate dimensional stability from shrinkage in wet cleaning and drying. Materials were weft-knitted from twenty-four different stitches with 7 gauge using a computerized flatbed knitting machine. Weight, thickness, density, and length were measured. A domestic washing machine and a tumble dryer were used for the shrinkage test. The results are as follows: Knitted fabrics were divided into 3 groups based on weight per unit area. Porous knits show light weight whilst milano, pintuck, rib stitches belong to the heaviest group. A positive correlation between weight and thickness was found and the same result was obtained for wale density and weight. Dimensional shrinkage of knitted fabrics was increased during repetitive wet cleaning and drying regardless of knit stitches. Especially, fabrics knitted with float, tuck, cable, and links & links stitches samples were contracted more than 15% in the first treatment whereas 2x1 rib stitch showed 1% shrinkage rate. Fisherman and milano stitches contracted in both course and wale direction with similar shrinkage rates. However, porous knits with float and tuck stitches shrank in course direction by 20% as well as cable samples contracted from 5% to 20% after repeated washing and drying. On the other hand, 30% and 15% contraction of wale direction occurred in orderly float and links & links stitches, respectively. Machine dried knits have a higher shrinkage rate than air-dried knits, but the drying method did not affect to the direction of contraction. In conclusion, variations of knit, tuck, and float stitches affect knit construction and dimensional stability from shrinkage in wet cleaning and drying of wool knitted fabrics.

• Journal of the Korean Society of Tobacco Science
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• v.19 no.2
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• pp.102-106
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• 1997

The inluence of styrofoam-panel thickness of floating frame on the seedling growth of flue-cured tobacco(Nicotiana tabacum L.) in the newly developed direct-seed float system was investigated . Floating frame used instead of styrofoam-tray consisted of styrofoam-panel (106×108cm) for floating, eight holes(1.Sx2S.0 cm) to uniform the water, and nutrition supply far seedling and water and nutrition absorption cloth placed on the styrofoam-panel. Each floating-frame may lay eight plastic-trays on it. Eight grades of styrofoam-panel thickness from 26 mm to 46mm and two kinds of media were used in the greenhouse system. Dry cells were found from the styrofoam-panel thickness of 43mm in carbonized chaff, compost and original soil rate of L3-3(v/v) media, and of 37mm in peat and perlite rate of 8-2(v/v) media. The thinner styrofoam-panel produced more tender and succulent seedling with the more trunk and the less root weight. When considering the appearance of dry cell, seedling growth, producing healthy tobacco seedlings, and utilization of styrofoam-panel for two kinds of medias the ideal styrofoam-panel thickness were suggested to be around 34mm for flue-cured tobacco reeling production in the newly developed direct-seeding float system. Key words : tobacco seedlings, float system, medium, styrofoam pannel, dry cell.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.2
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• pp.120-128
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• 2008

Estimation of the gear shape and cross section of sweep at mouth of a bottom trawl net was described and applied to the field experiments obtained with the Scanmar system. The shape of the trawl net from wingend to the beginning of codend was assumed to be part of an elliptic cone of which the cross section was ellipse, and that of the float rope be of form $y_f=a_fx^{bf}$. In case of a bottom trawl with warp 180m long, the radius of ellipse, the cross section of sweep at mouth, the eccentricity of the ellipse, the inclination angle of float rope and the contribution of the side panel to net height were estimated in accordance with towing speed. The horizontal radius of the upper ellipse increased with increasing towing speed, the eccentricity of it became slightly bigger as increasing the towing speed which meant the shape of it being flat. And the inclination angle of the float rope was about between 7 and 12 degrees in case of the above bottom trawl.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.471-474
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• 2002

A fuel tank contains water at the bottom under the fuel. The water comes from humidity by temperature change of inside and outside of tank. So it is necessary to measure both level to check precise amount of oil. But measuring instrument for level of water and fuel is not available yet. Since the fuel is inflammable, the sensor system must not include any electric circuits in the fuel tank. Optical cable sensor can satisfy this non-explosive condition. The displacement of a float changing by water level makes bending curvature of optical cable different. As the float rise up, the optical cable is bent more and the light signal in the cable decreases. The reduction of light signal is detected and it is converted into the change of water level. The output signal from a photo diode shows the proportional relation of water level. The increase of sensor voltage as a unit of ㎷ follows the level position of the float that is located between water and gasoline in the tank.

• Magazine of the Korean Society of Agricultural Engineers
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• v.37 no.1
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• pp.49-54
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• 1995

Three types of floating-type automatic inlet were developed for the purpose of reduc- ing farmer's working hours required for water management and saving irrigation water. The point of automation is to use a float within the inlet which is floated and sinked by the ponding depth of paddy field, Thus opens and closes the control gate of irrigation. Suitability of each inlet may depend on production cost, applicability to paddy field condi- tions, and feasibility to farmers, etc. The first model was composed of three parts : chamber for irrigation control gate, chamber for float controlled by ponding depth, and connection bar between the two parts. It was designed to open and close the control gate gradually as the ponding depth drops and rises to a certain level. The second model was designed to improve the weak point of the first model which is the imperfect-closing of gate when it approaches to the end of ir- rigation. A switch-spring was equipped above the connection bar for perfect opening and closing of gate when the ponding depth reaches to a certain level. The third model was designed by combining the two chambers, that is, cut in halves the inlet volume of the above two models. Magnets were equipped above the float for perfect opening and closing gate. The functional experiment for three developed inlets was successfully carried out and the rating curves were derived.