• Journal of the Korea institute for structural maintenance and inspection
• /
• v.18 no.3
• /
• pp.116-124
• /
• 2014

Penetration depth of inorganic waterproofing agent is difficult to assess quantitatively because inorganic waterproofing agent for concrete is not an internal waterproof membrane. However, evaluation of penetration depth of inorganic waterproofing agent is one of the most important evaluation index to secure efficiency in a consistent penetration. Therefore, this paper was proposed penetration depth measurement method of inorganic waterproofing agent for concrete and the penetration depth of the conventional inorganic waterproofing agent have been evaluated through the proposed penetration depth measurement method. As a result of test, the measured penetration depth throught the proposed penetration depth measurement method of inorganic waterproofing agent showed that more than 90% reliability.

• Journal of the Korea Furniture Society
• /
• v.19 no.2
• /
• pp.137-140
• /
• 2008

This experiment states the ultra pure distilled water penetration depth through ray parenchyma cell in radial direction of Castanea crenata. Heartwood penetration depth was 1.16 times lower than the depth in softwood and that difference was found statistically significant at 75.2 second of penetration. Following go-stop-go cycle, water penetrated in the ray parenchyma cell. At the beginning this speed was high and then it was decreased slowly. Water penetration depth result was compared with alcohol penetration depth. It was found that water penetration in ray parenchyma was found lower than alcohol due to the low surface tension of water.

• Progress in Superconductivity and Cryogenics
• /
• v.4 no.1
• /
• pp.50-54
• /
• 2002

Penetration depth of Nb electrodes in $Nb/A1O_x/Nb$ Josephson junctions has been measured by resistive method. For a given applied field, the total flux through the junction is temperature dependent because the penetration depth of Nb electrode varies with temperature. If the total flux equals an integral multiple of the flux quantum at certain temperatures, resistive peaks appear at those temperatures. The penetration depth of Nb can be determined by applying the above condition, The temperature dependence of penetration depth was found to be well described by the two-fluid model.

• Journal of Ocean Engineering and Technology
• /
• v.34 no.3
• /
• pp.202-207
• /
• 2020

A track-type underwater construction robot (URI-R) was developed by the Korea Institute of Ocean Science & Technology. Because URI-R uses tracks to move on the seabed, insufficient ground strength may hinder its movement. For smooth operation of URI-R on the seabed, it is important to determine the geotechnical properties of the seabed. To determine these properties, standard penetration test (SPT), cone penetration test (CPT), and sampling are used on land. However, these tests cannot be applied on the seabed due to a high cost owing to the vessel, crane, sampler, and analysis time. To overcome these problems, a free fall cone penetration tester (FFCPT) is being developed. The FFCPT is a device that acquires the geotechnical properties during impact/penetration/finish phases by free fall in water. Depth information is crucial during soil data acquisition. As the FFCPT cannot measure the penetration depth directly, it is estimated indirectly using acceleration. The estimated penetration depth was verified by results of real tests conducted on land.

• The Korean Journal of Ceramics
• /
• v.5 no.3
• /
• pp.270-277
• /
• 1999

The ballistic capability of an alumina-rich oxide armor ceramic against a shaped jet was characterized as a function of penetration depth in a layered target structure. The penetration resistance of the ceramic, based upon the determination of penetration velocity, was not equally realized throughout the depth of penetration. It was abnormally low at an early stage of penetration, followed by a sudden increase to reach ~16GPa thereafter. There was no apparent change in such a profile with respect to the lateral size of the specimen. Based upon 2-D flash x-ray radiography and 3-D Hull code simulation, the feasibility of forming a pressure-induced predamnaged zone in front of the jet tip was speculated to foster an increased penetration velocity in the initial stage penetration, resulting in the diminished penetration resistance. The disappearance of such a predamaged zone with penetration was interpreted to restore the resistance of the ceramic in the later penetration stage.

• Journal of the Korea Furniture Society
• /
• v.18 no.3
• /
• pp.243-247
• /
• 2007

An experiment was conducted to observe the safranine penetration depth in radial directions of Populus tomentiglandulosa. Radial penetration was considered from bark to pith. In radial direction, ray parenchyma and intercellular space were considered for the measurement of safranine penetration depth. It was found that sapwood conducted safranine 24.23% higher in radial direction compared with heartwood. Intercellular space conducted safranine 39.27% higher depth compared with ray parenchyma and the penetration depth was 39.41% higher in sapwood compared to heartwood. During safranine penetration, it formed a curvature in the lumen of ray parenchyma. Initially safranine penetration was found high and decreased gradually.

• Journal of the Korea Furniture Society
• /
• v.18 no.4
• /
• pp.312-316
• /
• 2007

A study was conducted to know 99.5% ethyl alcohol penetration depth in radial and longitudinal direction of Castanea crenata. Alcohol penetration depth was found higher in longitudinal direction by about 12.47 times. In both earlywood and latewood, fiber conducted alcohol in higher depth than that of large and small vessel. Penetration depth of alcohol after 15.0 second of penetration in longitudinal direction, there was no significant difference among fiber in sapwood and heartwood, and vessel in sapwood. At the beginning of penetration the speed was high and then gradually decreased.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.18 no.2
• /
• pp.154-159
• /
• 2015

This paper deals with the effect of concrete target size on penetration of projectiles. We investigated the penetration depth and residual velocity of projectiles using the 2-D axial symmetric model. Most analysis were conducted with 13 kg projectile (striking velocity: 456.4 m/s) and concrete target with compressive strength of 39 MPa. This paper provided penetration depth (or residual velocity) versus ratio D/d (target diameter, D and projectile diameter, d). When the bottom of concrete cylinder was constrained, penetration depth converged to limit depth more than the ratio D/d of 36. The residual velocity of projectile with thin concrete target were investigated. The residual velocity was converged to specific velocity more than the ratio D/d of 16.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.25 no.1
• /
• pp.82-88
• /
• 2015

Objectives: This study is designed to analyze the penetration performance into ceiling materials containing asbestos of scattering prevention agents and investigate the change in penetration depth and viscosity according to the dilution rate of anti-scattering agents diluted with distilled water. Methods: Five different types of scattering prevention agents were spread on plate-type asbestos ceiling materials. The penetration depth of each coated ceiling material was measured by energy dispersive spectroscopy (EDS) analysis, based on X-ray fluorescence (XRF) results of the non-coated ceiling materials. Test equipment installed the ceiling materials and 60 minutes were collected at a flow rate of $10{\ell}/min$ at a filter of 25 mm. Results: An EDS analysis of the cross-section of ceiling materials constructed with a scattering prevention agent revealed that potassium is detected in the process of penetrating hardener solidification and this element could be an indicator for infiltration. When anti-scattering agents with different viscosities were constructed and the penetration depth was analyzed by potassium detection assessment using EDS, the depth results with viscosities of 5.0, 2.5, and 1.9 cP were 98.5, 103, and $147{\mu}m$, respectively. Penetration performance improved with decrease in viscosity. Conclusions: For asbestos ceiling materials, it is concluded that a higher dilution rate of the scattering prevention agent leads to lower viscosity, and hence a deeper penetration depth from $156{\mu}m$ to 3 mm. The asbestos anti-scattering properties according to the penetration depth will be confirmed through further study.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2003.03a
• /
• pp.701-708
• /
• 2003

Recently, piezocone penetration test is frequently conformed in order to estimate the characteristics of soft ground with standard penetration test, generally used in the past. The soil characteristics, such as cone penetration resistance, friction resistence and excessive pore water pressure, can be evaluated continuously through the piezocone penetration test. In Incheon International Airport 2nd phase site preparation, standard penetration test and piezocone penetration test were used in order to increase the confidence for determination of soft ground depth. And the compressible layer was determined by the comparison between the preconsolidation pressure and the designed increase pressure. As the results, the relation between standard penetration test and piezocone penetration test shows q$_{c}$=(1.09~l.63)N at the soft ground, determined by 5/30 N value. And q$_{c}$=(1.21~l.98)N was shown at the point of compressible layer, evaluated by the preconsolidation pressure. These results were applied to determination for the depth of soft ground and to design the improvement for the soft clay.lay.