• Economic and Environmental Geology
• /
• v.47 no.6
• /
• pp.625-633
• /
• 2014

The Aquistore project is the world's first commercial capture, transportation, utilization and storage project of post-combustion $CO_2$ from a coal-fired thermo electric power plant, and the proposed storage is a saline aquifer at a depth of about 3,500 m. Deep saline aquifer, compared to hydrocarbon reservoir, provides the great volumetric potential for storage of $CO_2$ anywhere in the world, therefore the research results from the project may be exported globally to other sites. Geological $CO_2$ storage characterization for saline aquifer instead of hydrocarbon reservoir needs to estimate the geophysical properties of subsurface geology. This study calculated the geophysical property of water-saturated formation by applying amplitude variation analysis developed from oil and gas exploration. We correlated horizon tops at the well logs to seismic traveltime of 1,815 and 1,857 ms as Winnipeg and Deadwood formations. Gradient analysis from seismic traces showed correlation coefficient of 45 - 81 % on amplitude variation with respect to incident angle. Crossplot of intercept and gradient shows the inverse proportional trend which represents typical water saturated sediments. Product attribute of intercept and gradient described the base of wet sediment. Poisson's ratio change attribute increased at the top of target area satisfying with wet sediment and decreased at the top of basement in a dry rock bed.

• Journal of Animal Science and Technology
• /
• v.46 no.2
• /
• pp.137-144
• /
• 2004

Algorithms for estimating breeding values on several categorical data by using latent variables with threshold conception were developed and showed. Thresholds on each categorical trait were estimated by Newton’s method via gradients and Hessian matrix. This algorithm was developed by way of expansion of bivariate analysis provided by Quaas(2001). Breeding values on latent variables of categorical traits and observations on linear traits were estimated by preconditioned conjugate gradient(PCG) method, which was known having a property of fast convergence. Example was shown by simulated data with two linear traits and a categorical trait with four categories(CE=calving ease) and a dichotomous trait(SB=Still Birth) in threshold animal mixed model(TAMM). Breeding value estimates in TAMM were compared to those in linear animal mixed model (LAMM). As results, correlation estimates of breeding values to parameters were 0.91${\sim}$0.92 on CE and 0.87${\sim}$0.89 on SB in TAMM and 0.72~0.84 on CE and 0.59~0.70 on SB in LAMM. As conclusion, PCG method for estimating breeding values on several categorical traits with linear traits were feasible in TAMM.

• The KIPS Transactions:PartB
• /
• v.13B no.2 s.105
• /
• pp.77-82
• /
• 2006

Digital halftoning is the technique to obtain a bilevel-toned image from continuous-toned image. Among halftoning methods, the error diffusion method gives better subjective quality than other halftoning ones. But it also makes edges of objects blurred. To overcome the defect, we proposes the modified error diffusion to enhance the edges using the property that human vision perceives the local average luminance and doesn't perceive a little variation of the spatial variation. The proposed method computes a spatialactivity, which is the difference between a pixel luminance and the average of its $3{\times}3$ neighborhood pixels' Iuminance weighted according to the spatial positioning. The system also usesof edge enhancement (IEE), which is computed from the normalized spatial activitymultiplied by the average luminance. The IEE is added to the quantizer's input pixel and feeds into the halftoning quantizer. The quantizer produces the halftone image having the enhanced edge. The computer experimental results show that the proposed method produces clearer bilevel-toned images than conventional methodsand the edge of objects is preserved well. Also the performance of the preposed method is improved, compared with that of the conventional method by measuring the edge correlation and the local average accordance at some ranges of viewing distance.

• Korean Journal of Soil Science and Fertilizer
• /
• v.47 no.4
• /
• pp.262-268
• /
• 2014

The management of soil chemical properties is very important to sustainable agriculture of many horticultural crops, including cucumber. This study was conducted to find the optimal soil properties of environmentally friendly agriculture in controlled horticulture. Soil chemical properties of 267 samples were collected from soil in Chungnam Province. The average of pH, EC, OM, available $P_2O_5$, exchangeable K, Ca, and Mg was 6.1, $5.38dS\;m^{-1}$, $34g\;kg^{-1}$, $1,321mg\;kg^{-1}$, $1.50cmol_c\;kg{-1}$, $10.3cmol_c\;kg{-1}$, and $3.4cmol_c\;kg{-1}$, respectively. The organic matter content in silty clay loam was significantly higher than in the other soil textures, whereas the pH, EC, exchangeable K, and Mg in loamy fine sand showed significantly lower among soil textures. The EC value and exchangeable Mg concentration were highest in mountain foot-slope soils. The frequency distribution within optimum range of soil chemical properties was 26.2%, 30.3%, 2.3%, 3.8%, 3.4%, and 6.7% for pH, OM, available $P_2O_5$, exchangeable K, Ca, and Mg, respectively. Especially, excessive portion of available $P_2O_5$ and exchangeable Ca were 94.0% and 94.4%, respectively. The EC value and organic matter content of soil samples were positive correlation with all chemical properties except soil pH. In principle component analysis of chemical properties in soil samples, the percentage of variance explained by PC 1 was 52.2%, while PC 2 explained 21.3% of the variance, for a cumulative total of 73.5%. In conclusion, these results are considered to improve soil nutrient management for sustainable controlled horticulture.

• Research in Plant Disease
• /
• v.12 no.2
• /
• pp.108-114
• /
• 2006

This study was conducted to elucidate the interactions among soil microorganisms in a special field where one, two or three of N, P, K fertilizers were continuously not applied for 29 years. Crop yield (barley, soybean), soil chemical properties and microflora and microfauna including nematodes, nematophagous fungi, actinomycetes, bacteria, and fungi were examined for two years. Tylenchorhynchus sp. was the most important plant-parasitic nematode (range $11{\sim}642/300 cm^3$ soil) followed by Pratylenchus sp. and Helicotylenchus sp. Among nematophagous fungi, Monacrosporium spp. was the most frequently found followed by Harposporium sp. and Cystopage sp. In general, plots treated with phosphate fertilizer yielded more, had more nematodes, bacteria and actinomycetes. In contrast, total fungal population densities including nematophagous fungi, Cystopage sp. and Harposporium sp. were in reverse; they were more abundant in the plots with lower phosphate contents. Phosphate and pH are positively correlated and two most important determining factors for the population density of soil organisms under investigation. According to correlation analysis, Ca, Mg, and $SiO_2$ contents in soil and population densities of Tylenchorhynchus sp., saprophitic nematodes, actinomycetes, and bacteria were positively correlated with pH, but were negatively correlated with fungal population densities. We hope that the study will add an additional knowledges to understand our mysterious underworld.

• Journal of the Korean GEO-environmental Society
• /
• v.22 no.11
• /
• pp.15-21
• /
• 2021

Losses of both life and property increased from damage to underground pipe such as heat transmission pipe buried underground in downtown because pipes are gradually aging. Considering the characteristics of the heat transmission pipe, which is not exposed to the outside and difficult to immediately identify problems such as damage, it is realistic to indirectly check the condition of the facility based on the historical information that is periodically collected through facility maintenance. In this study, a methodology for estimating the damage probability was developed by examining the history information of the heat transmission pipe, deriving an evaluation factor that is related to the damage probability. The contribution factor of the damage probability were reviewed by analyzing not only the guidelines for maintenance of heat transmission pipe of advanced European countries and domestic district heating companies, but also the cases of waterworks with similar characteristics. Evaluation factors were selected by considering not only the correlation with the damage probability but also the possibility of securing data. Based on 1999, when the construction technology and standards of heat transmission pipe changed, the damage probability estimation function according to the period of use was divided into the case of being buried before 1998 and the case of being buried after 1999, and presented. In addition, the damage probability was corrected by assigning weights according to the measured data for each evaluation factor such as the diameter, use, and management authority.

• Journal of the Korea Convergence Society
• /
• v.12 no.12
• /
• pp.287-294
• /
• 2021

A near miss is an unplanned event that did not result in injury/illness, or property damage, but had potentials to do so. The importance of the near miss has been emphasized by many researchers and organizations. However, only a few studies have quantitatively approached the near miss from the viewpoint of safety culture. The purpose of this study is to investigate the current status of near miss reporting activities in manufacturing workplaces in Korea. It also aims to understand how the activities related with the safety culture and the occurrence of industrial accidents. To this end, a survey was conducted on manufacturing workplaces and the results were analyzed. As a result, there was a marked difference in the perception on near miss according to whether or not the near miss reporting activity was conducted. However, it was found that only 56% of the workplaces were carrying out the reporting activities. It was found that the number of near misses reported varied depending on the reward. Although no correlation could be found between whether or not the near miss reporting activities were carried out and the history of industrial accidents occurred, it was found that safety culture level was hier at the workplaces conducting the activities.

• Journal of the Korean Applied Science and Technology
• /
• v.35 no.4
• /
• pp.1285-1294
• /
• 2018

The purpose of this paper was to identify the relationship between the characteristics of community mental health, and to identify if mediatable contextual property acts as factor influencing community mental health. Data of 229 municipal population groups were collected from KNSO and The 6th Community Health Plan. The data were analyzed using ANOVA, Spearman correlation, and multiple regression analysis. The perceived stress showed significant difference depending on health budget, mental health budget, number of mental health personnel, and was negatively correlated with proportion of the elderly, employment rate, percentage of NBLS recipients, health budget, and number of mental health personnel. The depressive mood differed depending on the number mental health personnel, and was negatively correlated with percentage of NBLS recipients and number of mental health personnel. Mental health budget and number of mental health personnel were respectively influencing factor of perceived stress and depressive mood. Following the above result, in order to reduce the gap between the mental health of communities, the researcher suggests that mental health budget as well as overall health budget and the number of mental health personnel be enforced.

• Applied Chemistry for Engineering
• /
• v.30 no.4
• /
• pp.460-465
• /
• 2019

In this study, the optimization of active materials and the preparation of particulate adsorbents for the application of metal oxide-based adsorbents for the treatment of $H_2S$, an air pollutant and odorant, occurred in various industrial facilities were investigated. The adsorbents were prepared by using $TiO_2$, which has a high physicochemical stability and relatively high specific surface area among metal oxides and also by different kinds and contents of active materials. The correlation between the physicochemical property and adsorption performance of the adsorbents confirmed that the adsorbent containing KI, which is a typical alkali metal among the active metals, showed the highest adsorption performance. The relationship between the contents and the adsorption performance was non-proportional, but a volcano plot. From XRD, SEM and BET analyses, it was confirmed that the active material was exposed to the surface above a certain amount and also the adsorption performance was the best when the specific surface area and pore volume were $40{\sim}100m^2/g$ and $0.1{\sim}0.3cm^3/g$, respectively. For practical application, the adsorbent was granulated or coated on a ceramic support. It was also confirmed that the adsorbent showed high adsorption performance when the adsorbent was coated on the ceramic rather than that of the granulated support.

• Journal of the Korean GEO-environmental Society
• /
• v.20 no.2
• /
• pp.59-67
• /
• 2019

Using the results from laboratory soil test, field vane test and piezocone penetration test, the engineering characteristics of the soft ground at east side of Gwangyang Port, which is located at south coast of Jeollanam-do, were investigated and optimal piezocone penetration test depth was derived to calculate piezocone factor. In this paper, the results of 61 laboratory soil tests, 226 times of field vane tests and 26 piezocone penetration tests were used. The result of laboratory soil test suggested that some physical properties such as specific gravity, moisture content, liquid limit and plastic index and others are higher than other south coast regions, meanwhile uniaxial compression strength, undrained shear strength, defined as mechanical property, appeared to be relatively small, distributed widely. According to the plastic chart, the ground was classified as high compressibility clay and low compressibility clay, mostly represent to Type 3 clay by Robertson (1990)'s classification chart. Piezocone factor was calculated by empirical method, based on the undrained shear strength which was obtained by the field vane test. According to the analysis with 3 different depth range, to set the appropriate measured depth range of piezocone penetration for comparation, using average value of the range of 5 times the vane length showed the highest correlation.