• Culinary science and hospitality research
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• v.19 no.1
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• pp.179-188
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• 2013

This study was performed to examine the quality characteristics of goami baked yackwa. To determine the optimal amount of wheat flour for goami powder yackwa((100, 80:20, 60:40, 40:60, 20:80, 100), the measurement of weight, hardness, moisture contents, color value and sensory evaluation were carried out(yackwa dough 14g: 12mm to the height of the mold was formed, Baked conditions: $160^{\circ}C$, 20Min., Dip conditions: $60^{\circ}C$, 30Min.). As a result, weight after baked or dipped in syrup were heavier when made with 100% of wheat flour yackwa. The moisture contents and hardness were the highest in 100% goami yackwa. L-values, a-values and b-values were also the highest in 100% goami yackwa. In a sensory evaluation, the overall preference were the highest in 100% goami yackwa and 100% wheat flour yackwa. From these results, goami was shown to be possible to make high quality yackwa.

• Tunnel and Underground Space
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• v.15 no.1 s.54
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• pp.28-38
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• 2005

According to the recent development of measurement system utilizing one or a set of boreholes, visualization of the explored underground became to be a major issue. It induced even the introduction of monitoring apparatuses on the borehole wall with multi-function tool, but the usage of these was often limited by where is unfavorable rock condition and a few of engineers can approach. And so, a portable type of borehole camera with only the essential function has been investigated and a few of commercial models about this is recently being applied into the field condition. This paper was based on the monitoring results obtained using a commercial model by Dr. Nakagawa. Discontinuities in rock mass were the topic for the visualization, and it was studied how can visualize their three dimensional distribution and what a numerical formulation is needed and how to understand the visualization result. The numerical formulation was based on the geometric correlation between the dip direction / dip of discontinuous plane and the trend / plunge of borehole, a set of the equation of a plane was induced. As field application of this into two places, it is found that the above visualization methodology will be especially an useful geotechlical tool for analyzing the local distribution of discontinuities.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.771-776
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• 2017

The cover glass of mobile displays and photovoltaic cells needs a functional coating, such as an anti-reflection and self-cleaning coating. Numerous studies have been conducted on the engineering application of biomimetic functional surfaces, such as moth eye and lotus leaf Anti-reflection coantings of silica nanoparticles could enhance the light transmittance. $TiO_2$ photocatalyst coatings have been applied to self-cleaning functional films. In this study, transparent hydrophobic anti-reflective coatings consisting of thin layers of $SiO_2/TiO_2$ nanoparticles were fabricated on a slide glass substrate by the sol-gel process and dip-coating process. The dependence of the surface morphology of the functional coatings was investigated by the atomic force microscopy (AFM), contact angle measurement, and UV-visible spectroscopy. It was found that the coating of $TiO_2$ nanoparticles exhibited a high average transmittance comparable to that of the bare slide glass substrate in the visible light range. The bi-layered functional coating of 7 nm $SiO_2$/7nm $TiO_2$ nanoparticles exhibits a transparent hydrophobic surface with a contact angle of $110^{\circ}$ and an improvement of the average transmittance of 2.3% compared to the bare slide glass substrate in the visible light range.

• The Journal of Engineering Geology
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• v.27 no.2
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• pp.119-124
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• 2017

The waviness of Large Discontinuity rock is the one of important elements that judges the stability of rock slope. When the waviness of large discontinuity is measured in the field, there are many limitations Therefore this research was carried out to measure waviness of large rock discontinuities using 3D laser scanner to supplement this problem. This research established one 3D model that actual X, Y and Z coordinates through the integrated data gained from one that calculates waviness of base lock using CAD program was compared and analyzed to that of disc-clinometer. As its results, the high reliability of results could be recognized as it belongs to mechanical tolerance $1{\sim}2^{\circ}$ and the results belong to the measured values of Mean DIP and Mean are all within $1^{\circ}$. So, the investigation method of waviness of large discontinuity rock face using 3D laser scanner was verified as more prompt, effective and reliable method than conventional direct site measuring method.

• Journal of Conservation Science
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• v.37 no.5
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• pp.505-515
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• 2021

In this study, we evaluated the slope stability of the Pohang Daljeon-ri columnar joint (Natural Monuments # 415) and calculated the maximum energy, jumping height and moving distance of rockfalls using a simulation. Based on the results, we established the range of rockfall risk. The slopes of the Pohang Daljeon-ri columnar joint have dip directions of 93.79°, 131.99°, 165.54° and 259.84° from left (SW) to right (NE). Furthermore, they have a fan-like shape. The Pohang Daljeon-ri columnar joints are divided into four sections depending on the dip direction. The measurement results of the discontinuous face show that zone 1 is 125, zone 2 is 261, zone 3 is 262, zone 4 is 43. The results of slope stability analyses for each section using a stereographic projection method correspond to the range of planar and toppling failure. Although it is difficult to diagnose the type of failure, risk evaluation of currently falling rocks requires further focus. The maximum movement distance of a rockfall in the simulation was approximately 66 m and the rockfall risk range was the entire area under slope. In addition, it is difficult to forecast where a rock will fall as it rolls in various directions due to topographic factors. Thus, the installation of measures to prevent falling is suggested to secure the stability based on the results of the rockfall simulations and its probabilistic analysis.

• Korean Journal of Heritage: History & Science
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• v.41 no.1
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• pp.21-33
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• 2008

In this study, the researcher examined archaeomagnetic secular variation of Chungcheong Region through measured data of archaeomagnet obtained from 34 relics, which discovered in the baked earth from varied historic sites within the region. Furthermore, the researcher closely reviewed regional differences of geomagnetic field in the domestic territory. Reviewing the comparison between the measured data of archaeomagnet in Chungcheong Region and the archaeomagnetic secular variation of Japan, which has difference in distance, it reveals a noticeable change in declination by tilting more than 10 degree toward East in the year of about A.D. 300, although the feature of whole variation is quite similar. In other period of times, it was confirmed that the regional differences of geomagnetic field in which the magnetic dip became deeper to some degree, and the declination was tilted westward a little bit. Such patterns do not differ significantly from the pattern of entire archaeomagnetic secular variation of our country, and even in the direct comparison to the data of Chungcheong Region, the distinct regional difference in both periods before and after Christian era was not confirmed. The fact may become clearer that, when the volume of the measured data of archaeomagnet increases further, and when more data connected with varied time period are filled, the problem such as deviation of the measurement period of archaeomagnet caused by the regional difference of geomagnetic field would not be worrisome issue, especially in Korean territory, judging from the measured data of archaeomagnet of historic relics in Chungcheong Region. Besides, as great efforts are being exerted in order to get the most reliable measured data as much as possible in taking both samples and measurement, it is thought that there would be no problem not only in the issue of deviation of the measurement period involving with the measured data of archeomagnet, but also in the aspect of reliability of data.

• Tunnel and Underground Space
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• v.19 no.1
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• pp.52-63
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• 2009

This is a study on large-scale rock joint roughness measurements using LIDAR (light detection and ranging) and the Split-FX point cloud processing software. The large-scale rock Joint Roughness Coefficient (JRC) is calculated using the maximum amplitude of joint asperities over the profile length on large-scale Joint surfaces of rock. As the profile length increases, JRC decreases due to scale-effects of rock specimens and is non-stationary. Also JRC shows anisotropy depending on the profile direction. The profile direction is measured relative to either dip or strike of the large-scale joint.

• Journal of the Korean earth science society
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• v.32 no.6
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• pp.654-664
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• 2011

A field campaign of magnetotelluric (MT) and audio-frequency MT (AMT) survey was done at 36 measurement points as a complementary for the previous 44 MT measurements completed during the period of 2005-2006. The purpose of additional MT survey is to investigate the possible fracture system in Seokmo Island, which is conceived to be crucial in accumulation and migration of geothermal hot spring in this area. We have done 2D and 3D inversions of overall MT and AMT data distributed on a grid to interpret subsurface of extended area. The inversion results reveal that at least two major faults are imaged in the inversion results, one of which is in NNE-SWW with steep dip, and another is in E-W direction.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.382.2-382.2
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• 2014

We explain a method to fabricate multi-layered transparent conductive films (TCF) using graphene oxide (GO), copper powder and polyurethane (PU) solution. The flexible graphene nanosheets (GNSs) serve as nanoscale connection between conductive copper nanoparticles (CuNps) and PU nanofibers, resulting in a highly flexible TCF. To fabricate conductive films with high transmittance, polyurethane (PU) nanofibers were used for a conductive network consisting of CuNps and GNSs (CuNps-GNSs). In this experiment, copper powder and graphene oxides were mixed in deionized water with the ultrasonication for 2 h. NaBH4 solution is used as a reduction agents of CuNps and GNSs (CuNps-GNSs) under a nitrogen atmosphere in the oil bath at 100% for 24 h to mixed. The purified and dispersed CuNp-GNS were obtained in deionized water, and diluted to a 10wt.% based on the contents of GNSs. Polyurethane (PU) nanofibers on a PET substrate were formed by electrospinning method. PET slides coated with the PU nanofibers were immersed into CuNp-GNS solution for several second, rinsed briefly in deionized water, and dried to obtain self-assembled CuNp-GNS/PU films. The morphology of the multi-layered films were characterized with a field emission scanning electron microscope (FE-SEM, Hitachi S-4700) and atomic force microscope (AFM, PSIA XE-100). The electrical property was analysed by the I-V measurement system and the optical property was measured by the UV/VIS spectroscopy.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.292.2-292.2
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• 2013

Graphene, a two-dimensional graphite material consisting of sp2-hybridized carbons. The properties of graphene such as extremely high carrier mobility, high thermal conductivity, low resistivity, large specific make it a promising materail of divices and material. Typically, poly (methyl methacrylate) (PMMA) is used when graphene transfer to other substrates. To remove PMMA on graphene, people used to dip the graphene into the acetone. However, it is known that the remove of PMMA on the graphene is difficult to completely using the acetone. Therefore, to remove the PMMA on the graphene surface, many research groups have employed various methods such as the thermal treatment, photothermal method, and other solvent. Nevertheless, a part of PMMA still remain on graphene surface. Usually, to observe the residual PMMA on graphene surface, topography of graphene surface scanned by atomic force microscopy is used. However, in that case, we can not distinguish PMMA and other particles. In this study, to confirm the residual PMMA on graphene surface, we employed novel measurement technique which is available to distinguish PMMA and other particles by means of photothermal effect.