• Journal of Korean Library and Information Science Society
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• v.50 no.3
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• pp.49-69
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• 2019

The purpose of this study is to measure the saturation of the collection in public library and to propose a solution to this problem. In order to conduct this study, one local government was selected to measure the collection saturation status of each library and to clarify the cause of collection saturation. Based on the research results derived from this study, the public library in Korea measures the degree of collection saturation and recognizes the seriousness of collection saturation, and suggests the task of identifying the cause of collection saturation and solving it.

• Journal of Magnetics
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• v.22 no.2
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• pp.306-314
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• 2017

Nowadays power quality effects on induction motors have gained significant attention due to wide application of these motors in industry. The impact of grid voltage fluctuations on the induction motor behavior is one of the important issues to be studied by power engineers. The degree of iron saturation is a paramount factor affecting induction motors performance. This paper investigates the effects of voltage fluctuations on motor magnetic saturation based on the harmonic content of airgap flux density by finite element method (FEM). It is clarified that the saturation harmonics under normal range of voltage fluctuations have not changed significantly with respect to pure sinusoidal conditions. Experimental results on a 1.1 kW, 380 V, 50 Hz, 2 pole induction motor are employed to validate the accuracy of the simulation results.

• Journal of the Korean Geotechnical Society
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• v.24 no.6
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• pp.37-44
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• 2008

At low normal stress levels, tensile strength of sand characteristically varies with either saturation or suction of soil in an up-and-down manner with a peak tensile strength that can occur at any degree of saturation. A theory that accurately predicts tensile strength of wet sand was presented in the previous study. In this study, the results of uniaxial tensile, suction-saturation and direct shear tests obtained from three sands (Esperance sand from Seattle, Washington, clean sand from Perth, Australia, and Ottawa sand) are used to validate the proposed theory. The closed form expression of the proposed theory can predict well the experimental data obtained from these sands in terms of the variation patterns of tensile strength over the entire saturation regimes, the magnitude of the tensile strength, its peak value, and the corresponding degree of saturation when the peak strength occurs.

• Restorative Dentistry and Endodontics
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• v.35 no.2
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• pp.96-105
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• 2010

The purpose of this study is to observe and compare the remineralization tendencies of artificial enamel caries lesion by remineralization solutions of different degree of saturations at pH 5.5, using a polarizing microscope and computer programs (Photoshop, Image pro plus, Scion Image, Excel). For this study, 48 sound permanent teeth with no signs of demineralization, cracks, or dental restorations were used. The specimens were immersed in lactic acid demineralization solution for 2 days in order to produce artificial dental caries that consist of surface and subsurface lesions. Each of 9 or 10 specimens was immersed in pH 5.5 lactic acid buffering remineralization solution of four different degrees of saturation (0.507, 0.394, 0.301, and 0.251) for 12 days. After the demineralization and remineralization, images were taken by a polarizing microscope (${\times}100$). The results were obtained by observing images of the specimens, and using computer programs, the density of caries lesions were est mated. While the group with the lowest degree of saturation (0.251) showed total remineralization feature from the surface to the subsurface of the lesion, the group with the highest degree of saturation (0.507) showed demineralization mainly on the surface of the lesion at the constant organic acid concentration 0.01 M and pH 5.5.

• Korean Journal of Soil Science and Fertilizer
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• v.10 no.3
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• pp.189-201
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• 1977

Some of basic aspects of soil potassium with special reference to soil physical properties were discussed. Data in the Official Soil Series Description(Korea) was analyzed according to soil type, land form, and soil texture to find soil potassium status which may explain different response to potassium application. Exchangeable potassium contents decreased with soil depth irrespective of soil type, land form and soil texture. Change in degree of potassium saturation within soil profile was not so clear as exchangeable potassium but the degree of potassium saturation of A horizon was highest among soil horizon. Soils of terrace and mountain foot slope showed high values both in exchangeable potassium and degree of potassium sauration and only these two soils were classified as soils having exchangeable potassium higher than 0.3 meq per 100g of soil and degree of potassium saturation higher than 5.0%. Exchangeable potassium of fine loamy and fine clayey soils is higher than 0.3 meq per 100g of soil but degree of potassium saturation is lower than 4.0%. Degree of potassium saturation of sandy soils exceeds 5.0% but exchangeable potassium is very low. Soils of rolling, hilly, unmatured and alpine land soils have lower exchangeable potassium and show lower degree of potassium saturation. The highest distribution of exchangeable potassium content irrespective of soil horizons was shown in the range of 0.1-0.2 meq per 100g of soil. The highest distribution of degree of potassium saturation was in the range of 2.0-3.0% in A horizon and 1.0-2.0% in B and C horizons. Of the soil series concerned in this analysis, 27.3% in A horizon, 11.1% in B horizon and 4.0% in C horizon had exchangeable potassium higher than 0.3 meq per 100g of soil and 18.0% in A horizon, 6.3% in B horizon, and 4.1% in C horizon showed degree of potassium saturation higher than 5.0%. The low response of potassium application only to soils in terrace and mountain foot slope may be resulted from the high exchangeable potassium content and high degree of potassium saturation. It is concluded that a great response of potassium application to soils is expected especially in dry season.

• Geomechanics and Engineering
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• v.8 no.5
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• pp.675-685
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• 2015

Weathering is the breaking/cutting down process of rocks due to physical and chemical processes in natural as well as artificial environment including $CO_2$ injection for storage in the sediment, or natural resource recovery process. This study suggests an alternative method to estimate the degree of weathering for granites. A series of laboratory and field experiments are performed to measure electrical resistivities on various rock samples experienced different degrees of weathering and their residual soils under different saturation conditions. It is found that the normalized electrical resistivity increases with a decrease in water absorption and the saturation. Simple boundaries are suggested to identify the weathering degree of granites, based on limited data. Field test results for three sites confirm that the suggested method could be estimated well the degree of weathering of granites compared with the other methods suggested previously. Although further research is required, this study suggests that an electrical resistivity could be an effective approach to estimate the degree of weathering of granites compared with the other methods suggested previously.

• Journal of the Korean Geosynthetics Society
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• v.8 no.3
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• pp.35-44
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• 2009

The purpose of this study was to prevent spreading of contaminants from movement of underground water by creating a barrier using artificial freezing method on a soil contaminated by oils and various NAPLs. Specimens with 80% and 90% degrees of saturation were prepared to form freezing barrier using artificial freezing method. With increasing freezing time of freezing barrier, barrier was formed faster in the specimen with 90% degree of saturation by about an hour compared to the specimen with 80% degree of saturation. In addition, thinnest thickness of frozen barrier in both specimens was 50mm after 12 hours of freezing time, showing expansion of freezing area with time. The results of this study can be applied to barrier in waste reclamation sites and contaminated regions or to flow control of contaminants.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.686-691
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• 2010

Flash boiling takes place when the thermodynamic state of the liquid deviates from its saturation limit over which the liquid temperature exceeds by a certain degree of superheat. The liquid jet introduced into the lower pressure zone than the liquid saturation pressure experiences a sequence of the atomization and disintegrated into numerous faster and smaller droplets. In the present study spray characteristics for a flash swirl spray were experimentally investigated. Injectant temperature is raised by a high frequency dielectric heating method and local spray characteristics are instantly measured by Global Sizing Velocimetry (GSV, TSI Inc.). Dependence of dimensionless superheat degree and injection pressure on total and local SMDs and mean droplet size is quantitatively examined. The flash swirl spray has the relation in the injection pressure and nozzle diameter in order to determine the spray quality, including the dimensionless superheat degree. Small droplets occur in the void core and local droplet size distributions largely depend on the dimensionless superheat degree and the injection pressure.

• Journal of the Korean GEO-environmental Society
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• v.7 no.1
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• pp.55-66
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• 2006

Laboratory tests have revealed that the liquefaction resistance of sands depends strongly upon the degree of saturation, which is expressed in terms of the pore pressure coefficient, B. The velocity of compression waves(i.e. P-waves), which have been known to be influenced largely by the degree of saturation and can be measured conveniently in the field, appears as an indicator of saturation. In this paper, the Stokoe type torsional shear(TS) testing equipment is modified to saturate the specimen and measure the velocities of P-wave and S-wave and pore pressure buildup. The velocities of P-wave and S-wave for Toyoura sand from Japan is measured and compared at the various B-value (degree of saturation) which are partially saturated to fully saturated conditions. Additionally, the variation of the pore water pressure induced during undrained TS tests at the various B-value is measured and analyzed.

• The Journal of the Korea Contents Association
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• v.16 no.8
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• pp.671-680
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• 2016

This research suggested a new real-time traffic signal control algorithm using fusion data of the travel time and the occupancy rate. This research applied the travel time data of traffic information system to traffic signal operation, and developed the signal control process using the degree of saturation that was estimated from the travel time data. This algorithm estimates a queue length from the travel time based on a deterministic delay model, and includes the process to change from the queue length to the degree of saturation. In addition, this model can calculate the traffic signal timings using fusion data of the travel time and the occupancy rate based on the saturation degree. The micro simulation analysis was conducted for effectiveness evaluation. We checked that the average delay decreased by up to 27 percent. In addition, we checked that this signal control algorithm could respond to a traffic condition of oversaturation and detector breakdown effectively and usefully. This research has important contribution to apply the traffic information system to traffic signal operation sectors.