• Applied Microscopy
• /
• v.42 no.1
• /
• pp.35-42
• /
• 2012

The skin is the largest organ of the integument system whose surface is closely related to many physiological and pathological conditions. The skin surface is closely related to functional status of the epidermis and dermis. The outermost surface of the skin shows characteristic pattern defined by small furrows are called micro-relief. The micro-relief change is according to physiological and pathological conditions of the skin. But, there is no data on health Korean skin micro-relief yet. This study presents some aspect of health Korean skin micro-relief from the twenties. The silicon replicas obtained from forearm, dorsum hand and finger were analyzed by profiles were accessed by stereoscopy. We measured density of furrow, width of furrow, and depth of furrow in micro-relief with sectioned silicon replica sample using stereoscope. Stereoscopic analysis showed that male group has a larger density of furrow and depth furrow in finger significantly. The densities of furrow were shown different not only between forearm and finger but also between finger and hand in male with female group. In conclusion, there were differences results between sex different and regional difference in skin replica profile. These quantitative data can be used for basis of further skin research for Korean.

• Journal of the Korean Geophysical Society
• /
• v.8 no.1
• /
• pp.45-48
• /
• 2005

In order to investigate the velocity structure of the southern part of the Korean peninsula, exploded seismic signals were recorded for 120 s along a 294-km WNW-ESE line and 150 s along a 335-km NNW-SSE line in 2002 and 2004, respectively. Velocity tomograms were derived from inverting first arrival times. One-dimensional velocity models derived by joint analyses of teleseismic receiver functions and surface wave dispersion at several stations near the profiles were uesd to build initial models. The raypaths indicate several midcrust interfaces including ones at approximate depths of 2.0 and 14.9 km with refraction velocities of approximately 6.0 and 7.1 km/s, respectively. The deepest significant interface varies in depth from 30.8 km to 36.1 km. The critically refracting velocity varies from 7.8 to 8.1 km/s along this interface which may correspond to the Moho discontinuity. The velocity tomograms show (1) existence of a low-velocity zone centered at 6-7 km depth under the Okchon fold belt, (2) extension of the Yeongdon fault down to greater than 10 km, and (3) existence of high-velocity materials under the Gyeongsan basin whose thickness is less than 4.2 km.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.7 no.6
• /
• pp.1047-1055
• /
• 2006

We patterned nano-width lines on a super hard bulk diamond substrate by varying the ion beam current and ion beam sources with a dual beam field ion beam (FIB). In addition, we successfully fabricated two-dimensional nano patterns and three-dimensional nano plate modules. We prepared nano lines on a diamond and a silicon substrate at the beam condition of 30 kV, 10 pA $\sim$ 5 nA with $Ga^+$ ion and $H_2O$ assisted ion sources. We measured each of the line-width, line-depth, etched line profiles, etch rate, and aspect ratio, and then compared them. We confirmed that nano patterning was possible on both a bulk diamond and a silicon substrate. The etch rate of $H_2O$ source can be enhanced about two times than that of Ga source. The width of patterns on a diamond was smaller than that on a silicon substrate at the same ion beam power The sub-100 nm patterns on a diamond were made under the charge neutralization mode to prevent charge accumulation. We successfully made a two-dimensional, 240 nm-width text of the 300-lettered Lord's Prayer on a gem diamond with 30 kV-30 pA FIB. The patterned text image was readable with a scanning electron microscope. Moreover, three dimensional nano-thick plate module fabrication was made successfully with an FIB and a platinum deposition, and electron energy loss spectrum (EELS) analysis was easily performed with the prepared nano plate module.

• The Korean Journal of Petroleum Geology
• /
• v.10 no.1_2 s.11
• /
• pp.18-22
• /
• 2004

To identify and interpret the distribution and the characteristics of the gas hydrate layers in the Ulleung Basin, we have surveyed and gathered the multi-channel seismic data, Chirp sub-bottom profiler, SeaBeam and 12 m piston core samples since 1996. In previous works, high-resolution seismic profiles showed acoustic anomalies such as acoustic void, acoustic turbidity and pock mark which indicate the presence of gas-charged sediments. The patterns of horizontal degassing cracks originated from free methane expansion is the strong indicator of shallow gas-charged sediments in the core samples. The observation of submarine slides and slumps from destabilizing the sediments in the southern part of the Ulleung Basin may also point out that the gas had been released from gas hydrate dissociation during lowstand of sea level. The multi-channel seismic data show BSR, blanking and phase reversal. The gas hydrate layers above which large-scale shallow gases are distributed exist at the depth of about 200 m from the sea-floor with water depth of 2,100 m. From the interpretation of seismic sections in the southern Ulleung Basin, gas hydrate layers occur in the Pleistocene-Holocene sediments. These gas-charged sediments, acoustic anomalies and BSR may be all related to the existence of gas hydrate layers in the study area.

• Korean Journal of Soil Science and Fertilizer
• /
• v.22 no.1
• /
• pp.1-5
• /
• 1989

This study was carried out by using laboratory data to calculate Soil Moisture Control Section (SMCS) for medium textured topo-sequential soils derived from porphyry in Milyang area. The soils studied were characterized by loam to silty clay loam, and the moisture content at -1/3 bar in the solum ranged around 21.06% to 32.42%. The moisture contents per centimeter of soil layer within a solum calculated at field capacity (FC) ranged from 0.11cm to 0.19cm. The upper boundaries of SMCS of the soils calculated on the basis of FC as the water content at -1/3 bar, ranged from 16.2cm to 21.2cm and the lower boundaries from 44.4cm to 63.8cm, and the depth of SMCS were from 27.7cm to 42.6cm in the soil profiles. The Bongsan soil on the summit had shallower in the boundaries and narrower in the depth of SMCS than the soils on side-slopes or on valley.

• Korean Journal of Soil Science and Fertilizer
• /
• v.32 no.4
• /
• pp.365-374
• /
• 1999

To obtain informations on vertical movements of water and solute in rice paddy field during the growing season, soil water contents and bulk electrical conductivities (${\sigma}_a$) were monitored using Time Domain Reflectometry. Soil water contents with depth showed ${\varepsilon}$-shaped profiles constituting of partly saturated zones at top and bottom layers and unsaturated zones (20-100cm) between them. Analysis by fitting with a van Genuchten-type model showed that soil water contents at 60cm were affected by both water supplied from surface water and groundwater, but at 80cm mainly affected by groundwater. Water percolation at the rate of 2cm $day^{-1}$ rates were, but large fluctuation from 10 to 38cm $day^{-1}$ in C1 layer (60-90cm). Therefore, it can be said that any water or solute entering C1 layer is very rapidly transported to C2 layer, especially during the period of high groundwater table staying, and retarded to a relatively constant percolation rate in C2 layer. This can be manifested by the fact that rapid decrease and steady increase of electrical conductivities at 50 and 110cm depth respectively, were found around that period.

• Korean Journal of Ecology and Environment
• /
• v.51 no.4
• /
• pp.253-258
• /
• 2018

Phytoplankton community was studied in relation to a typhoon at Bok-gyo Bridge area in Juam Lake, Korea. In August 31, 2000, a typhoon (Prapiroon) was passed by Juam Lake with great power enough to destroy summer stratification of Juam Lake. Destratification resulted in temporal mixing of the whole water column and changed the physical and chemical properties of water bodies, and caused the changes of the biological properties. The transparency decreased from 195 cm before the typhoon to 84 cm after the typhoon with the resuspension of the bottom sediment. In the vertical distribution of the phytoplankton population, the maximum population was measured at depth of 2 m before the typhoon. However, immediately after the typhoon, the population distributed evenly throughout the entire water layers. The carbon biomass of the phytoplankton was also highest at the depth of 2 m before the typhoon, but immediately after the typhoon, it was uniformly distributed throughout the whole water layers. The vertical profiles of the concentrations of chlorophyll a, however, did not show a significant difference before and after the typhoon. The typhoon induced destratification and restratification altered the taxa of the phytoplankton. The major dominant phytoplankton taxa before the typhoon was diatoms including Aulacoseira granulata, but the green algae overwhelmed the diatoms in cell number and biomass after the typhoon. The chlorophycean dominance was replaced by cyanophycean dominance with the heavy rain and descent of water temperture at the end of September.

• Journal of Magnetics
• /
• v.11 no.1
• /
• pp.25-29
• /
• 2006

Recent experiments have demonstrated high TMR ratios in MTJs with the MgO barrier [1,2]. The CoFeB/MgO/CoFeB junctions showed better properties than the CoFe/MgO/CoFe junctions because the MgO layer had a good crystalline structure with (001) texture and smooth and sharp interface between CoFeB/MgO [3]. The amorphous CoFeB with 20 at%B starts the crystallization at $340^{\circ}C$ [4] and this crystallization of the CoFeB helps obtaining the high TMR ratio. In this work, the compositional changes in the MgO barrier and at the interface of CoFeB/MgO/CoFeB after the CoFeB crystallization were studied in annealed MTJs. XPS depth profiles were utilized. TEM analyses showed that the MgO barrier had (100) texture on CoFeB in the junctions. B in the bottom CoFeB layer diffused into the MgO barrier and B-oxide was formed at the interface of CoFeB/MgO/CoFeB after the CoFeB crystallization.

• Korean Journal of Materials Research
• /
• v.2 no.4
• /
• pp.285-292
• /
• 1992

Ultrathin(8nm) oxynitride (SiOxNy) film have been formed on Si(100) by rapid thermal processing(RTP) in $O_2$and $N_2$O as reactants. Compared with conventional furnace $O_2$ oxide, the oxynitride dielectrics shows better characteristics of I-V and TDDB, and less flat-band voltage shift. The oxynitride has a behavior of Fowler-Nordheim tunneling in the region of V 〉${\varphi}_0$ simialr to pure Si$O_2$oxide. The relative dielectric constant of oxynitride is higher than that of conventional pure oxide. Excellent diffusion harrier property to dopant(B$F_2$) is also observed. Nitrogen depth profiles by SIMS, AES, and XPS show nitrogen pile - up at Si$O_2$/Si interface, which can explain the improved properties of oxynitride dielectrics.

• Economic and Environmental Geology
• /
• v.27 no.2
• /
• pp.191-199
• /
• 1994

We have developed an algorithm based on the method of integral equations to simulate the magnetotelluric (MT) responses of three-dimensional (3-D) bodies in a layered half-space. The inhomogeneities are divided into a number of cells and are replaced by an equivalent current distribution which is approximated by pulse basis functions. A matrix equation is constructed using the electric Green's tensor function appropriate to a layered earth, and is solved for the vector current in each cell. Subsequently, scattered fields are found by integrating electric and magnetic Green's tensor functions over the scattering current About a 3-D conductive body near the earth's surface, interpretation using 2-D transverse electric modeling schemes can imply highly erratic low resistivities at depth. This is why these routines do not account for the effect of boundary charges. However, centrally located profiles across elongate 3-D prisms may be modeled accurately with a 2-D transverse magnetic algorithm, which implicitly includes boundary charges in its formulation. Multifrequency calculations show that apparent resistivity and impedance phase are really two complementary parameters. Hence, they should be treated simultaneously in broadband MT interpretation.