• The Journal of the Convergence on Culture Technology
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• v.8 no.6
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• pp.765-773
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• 2022

This study is a study on the application of a horizontal excavation machine system to improve constructability. In this study, the structural stability of non-covered temporary facilities was evaluated by comparing field measurements and numerical analysis. In addition, the appropriateness of the measurement results was analyzed by comparing and analyzing the results of numerical analysis with the analysis results applying the Gaussian probability density function to the measurement results. In this study, structural safety and long-term durability of the linkage were analyzed based on numerical analysis. As a result of the study, it was analyzed that the non-open cut method (H.A.S. method) of this study secures structural safety and constructability as the behavior in the actual construction process is more safe than the numerical analysis results, even if the uncertainty of the ground condition is taken into account.

• Journal of the Korean Geotechnical Society
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• v.25 no.2
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• pp.37-44
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• 2009

In this study, estimation methodology for the pile of ultimation lateral resistance, pu, and ultimate lateral capacity, Pu, is based on the CPT cone resistance $q_c$. Preexistent methodologies for ultimate lateral resistance and ultimate lateral capacity have been generally represented with relative density, vertical effective stresses, and various $K_0$ values which are important for analyzing sandy soil. These methodologies, however, did not consider the horizontal effective stress and the effects of construction site conditions. Therefore, CPT-based methodology for the estimation of the ultimate lateral pile load capacity Hu was proposed. Calibration chamber test results were analyzed and compared with calculated results. The proposed estimation methodology for the pile of $p_u$ can be effectively utilized as alternative to preexistent methods.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.4
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• pp.138-146
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• 2007

Geotechnical performance at the soft ground is strongly dependent on the properties of the soil beneath and adjacent to the structure of interest. These soil properties can be described using deterministic and/or probabilistic models. Deterministic models typically use a single discrete descriptor for the parameter of interest. Probabilistic models describe parameters by using discrete statistical descriptors or probability distribution density functions. The consolidation process depends on several uncertain parameters including the coefficients of consolidation and coefficients of permeability in vertical and horizontal directions. The implication of this uncertain parameter in the design of prefabricated vertical drains for soil improvement is discussed. A sensitivity analysis of the degree of consolidation and calculation of settlements to these uncertain parameters is presented for clayey deposits.

• Journal of Korean Ophthalmic Optics Society
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• v.7 no.2
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• pp.181-187
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• 2002

Curvature of Crystalline lens changes by Accommdation's change. When Accommdation gives force vertically to Crystalline lens that is elastic body, length increases for vertex direction. Density distribution and form of Crystalline lens that receive force lean to posterior surface, horizontal force of anterior surface direction is bigger more than horizontal force of posterior surface direction. But, if Accommdation begins to grow more than threshold value, expansity reaches in limit on anterior surface. This time, horizontal force of posterior surface direction is great mored more than horizontal force of anterior surface direction, thickness of posterior surface direction increases because is more than anterior surface direction. Anterior and posterior relationship thickness change difference accomplish the 2-nd funtional line(${\Delta}=B_1D+B_2D^2$) about Accommdation. Thickness (${\Delta}t_a$, ${\Delta}t_p$) difference change curved line of anterior pole-border and border-posterior pole by Accommdation is expressed as following. $${\Delta}t_a=t_a-t_{ao}=t_{max}+t_0{\exp}(-A/B)-t_{ao}$$ $${\Delta}t_p=t_p-t_{po}=t_{min}+t_0{\exp}(A/B)-t_{po}$$ The Parameter value that save in human's Crystalline lens obtain $t_{min}=1.1.06$, $t_0=-0.33$, B=9.32 in anterior, and $t_{max}=1.97$, $t_0=0.10$, B=7.96 etc. in posterior. Vertex curvature radius' change is as following Crystalline lens' anterior and posterior by Accommation $$R=R_0+R_1{\exp}(D/k)$$ The Parameter value that save in human's Crystalline lens obtain $R_{min}=5.55$, $R_1=6.87$, k=4.65 in anterior, and $R_{max}=-68.6$, $R_1=76.7$, k=308.5 in posterior, respectively.

• Journal of Radiation Industry
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• v.17 no.4
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• pp.471-479
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• 2023

In In-situ radioactivity measurement techniques, efficiency calibration models use predefined models to simulate a sample's geometry and radioactivity distribution. However, simplified efficiency calibration models lead to uncertainties in the efficiency curves, which in turn affect the radioactivity concentration results. This study aims to develop an efficiency calibration optimization methodology to improve the accuracy of in-situ gamma radiation measurements for byproducts from industrial facilities. To accomplish the objective, a drive mechanism for rotational measurement of an byproduct simulator and a sample was constructed. Using ISOCS, an efficiency calibration model of the designed object was generated. Then, the sensitivity analysis of the efficiency calibration model was performed, and the efficiency curve of the efficiency calibration model was optimized using the sensitivity analysis results. Finally, the radiation concentration of the simulated subject was estimated, compared, and evaluated with the designed certification value. For the sensitivity assessment of the influencing factors of the efficiency calibration model, the ISOCS Uncertainty Estimator was used for the horizontal and vertical size and density of the measured object. The standard deviation of the measurement efficiency as a function of the longitudinal size and density of the efficiency calibration model decreased with increasing energy region. When using the optimized efficiency calibration model, the measurement efficiency using IUE was improved compared to the measurement efficiency using ISOCS at the energy of ²²⁸Ac (911 keV) for the nuclide under analysis. Using the ISOCS efficiency calibration method, the difference between the measured radiation concentration and the design value for each simulated subject measurement direction was 4.1% (1% to 10%) on average. The difference between the estimated radioactivity concentration and the design value was 3.6% (1~8%) on average when using the ISOCS IUE efficiency calibration method, which was closer to the design value than the efficiency calibration method using ISOCS. In other words, the estimated radioactivity concentration using the optimized efficiency curve was similar to the designed radioactivity concentration. The results of this study can be utilized as the main basis for the development of regulatory technologies for the treatment and disposal of waste generated during the operation, maintenance, and facility replacement of domestic byproduct generation facilities.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.3
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• pp.259-268
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• 2010

Data on squid catches by the Korean jig fishery in sea blocks ($30'{\times}30'$), water temperatures at depth(30m, 50m and 100m) and zooplankton biomass in the East Sea from 1980 to 1999 were analyzed to examine the mechanism of formation of the high density stock area. Japanese common squid (Todarodes pacificus) catch in the East Sea was low in 1980s, while the catch was high in 1990s. The five sea blocks (No. 76, 82, 83, 87, 88) of the southern part in the eastern coastal waters of Korea showed high levels of percentage of total catch (35.1%), whereas the four sea blocks (No. 65, 71, 72, 78) of the coastal waters of Uleung Island showed high levels of percentage of CPUE (61.2%) for 20 years. Squid catches showed monthly fluctuations according to the vertical distribution of optimum water temperature for fishing ($14^{\circ}C{\sim}19^{\circ}C$). High total catch and high CPUE area matched well with $10^{\circ}C$ isothermal lines at 100m depth indicating northern limiting of Tsushima Warm Current, and temporal and spatial change in $10^{\circ}C$ isothermal line caused the change in total catch and CPUE. Horizontal distribution of zooplankton biomass by sea block was not matched well with those of total catch and CPUE, however pattern of time-series change in total zooplankton biomass was similar to that in total squid catch.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.6
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• pp.737-747
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• 1999

To estimate biomass and distribution of the Antarctic krill (Euphausia superba), hydroacoustic survey was conducted on board of R/V Yuzhmorgeologiya, which was chartered by Korea Antarctic Research Program (KARP) group from 18 to 21 December 1998, in the northern part of the South Shetland Islands, Antarctic Ocean, The scientific echo sounder (towing body type) used was EK- 500 (SIMRAD, Norway) with echo integrator (BI-500) at 38 kHz frequency and recorded mean backscattering cross-section coefficient (SA) per 1 $mile^2$ of sea surface. Also, Bongo net sampling was carried out to determine the size of krill and CTD (Conductivity, Temperature and Depth) casting to understand physical structure. Water column was divided into 5 layers (22$\~$65 m, 65$\~$115 m, l15$\~$65 m, 165$\~$215 m and 215$\~$315 m) to know vertical distribution of krill biomass. The standard length of krill collected was between 30 mm and 51 mm, and adult krill had single mode (41 mm). Maximum horizontal length of krill patch was about 35 nautical mile and vertical thickness was about 275 m. High density of krill was appeared in frontal area between Circumpolar Deep Water (>$1^{\circ}C$) and very low temperature water mass (< $-0.5^{\circ}C$) that originate from Weddell Sea. According to the results calculated using target strength equation, krill density was totally higher in continental slope and open water areas than in coastal area. In the study area, krill seems to distribute in depth; density was low at first layer ($\={\rho}=17.0\;g/m^2$) and higher at fourth layer ($\={\rho}=40.19\;g/m^2$). The estimated krill biomass at total survey area and water column was about 2.77 million metric ion ($\={\rho}=151.0\;g/m^2$) and coefficient of valiance ( CV, $\%$) was 19.92. The proportions and biomass of krill biomass at each layer were as follows; layer 1 ($11.3\%$, 0.31 million metric ton, CV=16.24), layer 2 ($13.3\%$, 0.37 million metric ton, CV=34.91), layer 3 ($23.7\%$, 0.66 million metric ton, CV=41.5), layer 4 ($26.6\%$, 0.74 million metric ton, CV=27.84) and layer 5 ($25\%$, 0.69 million metric ton, CV= 26.83).

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.2
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• pp.141-151
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• 2010

Harmful algal blooms (HABs), commonly known as red tides, are aquatic phenomena caused by the rapid growth and accumulation of certain microalgae, which can lead to marked discoloration of surface waters, and severe impacts on public health, commerce, and the environment. In South Korea, the red tides have been a serious and recurrent problem, especially along the south coast. Plenty of yellow loess was used to control an outbreak of the red tides for 15 years from 1996 until now. Yellow loess was almost sprayed in the vicinity of a large fish farming industry. In this research, the distribution characteristics and density distribution of zooplankton were investigated in autumn (Oct. 2008) and spring (Apr. 2009) using volume backscattering strength (SV) calculated by the zooplankton collected with north pacific standard (NORPAC) net and the echo intensity measured with ADCP at stations on the study area in the spraying ocean of yellow loess (SOYL), and the non-spraying ocean of yellow ocean (NOYL) by the red tide generating every year. The species number and the individuals per unit volume of the zooplankton collected in NOYL was high and it which was collected in SOYL was low. As a result of comparing the volume backscattering strength ($SV_c$) calculated by species and length of the zooplankton collected with NORPAC net with the volume backscattering strength ($SV_m$) calculated by the echo intensity measured with ADCP at stations on the study area, although $SV_c$ and $SV_m$ of NOYL were generally in agreement, $SV_m$ of SOYL was higher than $SV_c$ 4.3dB, i.e. ADCP is greatly influenced by suspended solid in SOYL. The horizontal distribution map of $SV_m$ at the study area in autumn (Oct. 2008) and spring (Apr. 2009) was drawn. $SV_m$ of SOYL is higher than NOYL and autumn is higher than spring. $SV_m$ can suppress the overestimate or underestimate of $SV_c$.

• The Journal of the Petrological Society of Korea
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• v.26 no.3
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• pp.297-309
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• 2017

Jurassic granite from Geochang was analysed with respect to the characteristics of the rock cleavage. The comprehensive evaluation for rock cleavages was performed through the combination of the 16 parameters derived from the enlarged photomicrographs of the thin section and the spacing-cumulative frequency diagrams. The results of analysis for the representative values of these spacing parameters with respect to the rock cleavage are summarized as follows. First, the above parameters can be classified into group I (spacing frequency (N), total spacing ($1m{\geq}$), constant (a), exponent (${\lambda}$), slope of exponential straight line (${\theta}$), length of line (oa') and trigonometric ratios ($sin{\theta}$, $tan{\theta}$) and group II (mean spacing (Sm), difference value between mean spacing and median spacing (Sm-Sme), density (${\rho}$), lengths of lines (oa and aa'), area of a right-angled triangle (${\Delta}oaa^{\prime}$) and trigonometric ratio($cos{\theta}$). The values of the 8 parameters belonging to group I show an order of H(hardway, H1+H2)

• Korean Journal of Agricultural Science
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• v.12 no.2
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• pp.282-291
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• 1985

In order to investigate the settlement characteristics of fill dam with decomposed granite is used as a embankment material instead of conventional clay collected behavoir of Andong dam and analyzed. Andong dam is the use of decomposed granite in the embankment material, and various type of gauges were installed in dam to measure a pore pressure, interval vertical settlement, dam crest settlement, relative settlement, surface settlement and internal horizontal movement. The results were summerized as follows; 1. With the increase of embankment loading, the settlement of core zone during construction increased with linear and under the effective stress $7kg/cm^2$ vertical settlement ratio ranged between 0.1 and 0.8% approximately and showed smaller value than that of fill dam with clay were used as a embankment material. 2. Though embankment loading was increased with about over central part of embankment height, the settlement of core zone in the lower part of the embankment was influenced slightly. 3. Pore pressure responsed sensitively with the increase of coefficient of permeability in core zone and settlement increased with pore pressure were dispersed. 4. During construction relative settlement in the lower part of the embankment has the largest influence on magnitude of the relative density and after construction settlement showed larger value in the core zone which has the largest compression height. 5. Settlement distribution of dam crest showed larger value in the central part, maximum section of dam, but smaller value in near the abutment.