• Analytical Science and Technology
• /
• v.24 no.6
• /
• pp.503-509
• /
• 2011

Specific surface area is becoming a very important factor when newly developed advanced nano-materials are evaluated. But there have been many differences in results when measuring specific surface areas, depending on the measuring equipments and analysis method. To verify the reliability of the specific surface area measurement device supplied within the country, Round Robin Test (RRT) has been done at 21 affiliated research institutes. As a result, it was found that several institute had problems in measuring of gas adsorption amount in measuring equipment, and this proved the need for certified reference material (CRM). Furthermore, it was also found that the results from BET analysis is easily swayed by the analyst's subjectivism, and the calculated results may differ up to 16% in case of CRM I depending on the selection range of BET analysis. So this showed that a standard guideline for BET constant C value and fitting correlation coefficient R is needed, to properly select range in BET analysis. The experience in RRT, distribution of CRM, and standardized procedure would result in improved reliability in industrial processes, and thus, would contribute to the quality management, the productivity improvement, the safety evaluation, and the new material development.

• Analytical Science and Technology
• /
• v.25 no.6
• /
• pp.350-363
• /
• 2012

To determine ionic species in snowpit samples using ion chromatography system, we described the performance of ion chromatography(IC) system, cleaning method of bottle, and interference by filtering procedure. The limit of detection, reproducibilities, and accuracies determined with BCR$^{(R)}$-408 were 0.01-0.26 ${\mu}g$/L, 0.4-17.4%, 4.5-12.0% for cations and 0.02-0.26 ${\mu}g/L$, 0.1-27.6%, 1.3-5.6% for anions, respectively. Lab blank test for sample bottle indicated that $CH_3CO_2{^-}$, $HCO_2{^-}$, and $NH_4{^+}$ can be easily contaminated in the lab environment. The positive interferences of $NO_3{^-}$ were partly attributed to the cleaning method of bottle. The filtering of melted snow sample should be carefully applied because it can positively affect the concentration levels of some ionic species. Finally, this method was applied to measure ionic species in snowpit samples from the upward area near NEEM camp and the uncertainties of measurement data of $F^-$ were also estimated.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.26 no.1
• /
• pp.45-52
• /
• 2006

This study was carried out to explore the accuracy of Near Infrared Reflectance Spectroscopy (NIRS) fer the prediction of digestibility and energy value of corn silages. The spectral data were regressed against a range of digestibility and energy parameters using modified partial least squares(MPLS) multivariate analysis in conjunction with first and second order derivatization, with scatter correction procedure(SNV-Detrend) to reduce the effect of extraneous noise. Calibration models for NIRS measurements gave multivariate correlation coefficients of determination$(R^2)$ and standard errors of cross validation of 0.92(SECV 1.73), 0.91(SECV 1.13) and 0.93(SECV 1.74) for in vitro dry matter digestibility(IVDMD), in vitro true digestibility(IVTD), and cellulase dry matter digestibility(CDMD), respectively. The standard error of prediction(SEP) and the multiple correlation coefficient of validation$(R^2v)$ on the validation set(n=39) was used in comparing the prediction accuracy. The SEP value was 0.30(TDN), 0.01(NEL), and 0.01(ME). The relative ability of NIRS to predict digestibility and energy value was very good for CDMD, total digestible nutrients(TDN), net energy fer lactation(NEL) and metabolizable energy(ME). This paper shows the potential of NIRS to predict the digestibility and energy value of con silage as a routine method in feeding programmes and for giving advice to farmers.

• Research in Plant Disease
• /
• v.22 no.2
• /
• pp.94-99
• /
• 2016

For the purpose of practical application of gamma irradiation for export lily without the ionic energy damage, 150 Gy gamma ray was suggested as the safe level on cut lilies, the oriental cultivar Siberia (white) and Sorbonne (pink). The combined treatments of 150 Gy gamma ray and sodium dichloroisocyanurate (NaDCC) at 0, 40, 100, and $200{\mu}g/l$, were tried to control lily leaf blight caused by Botrytis elliptica. Incidences of petal blight on the two oriental lilies at control were 93%-95%, whereas those at the combined treatments of 150 Gy and $100{\mu}g/l$ or higher of NaDCC were 76%-83%. However, severity of petal blight was not reduced by the combined treatments. Gamma irradiation at 150 Gy did not change the cut lily quality such as improve cut lily longevity of vase-life compare with the control. In addition, fresh weight, chlorophyll contents, and the color of pink petals of Sorbonne were not changed by 150 Gy of gamma irradiation. Therefore, we recommend the combined treatment of 150 Gy gamma irradiation and $100{\mu}g/l$ NaDCC for the standard operating procedure on cut lily for export quarantine to control leaf blight.

• Journal of Soil and Groundwater Environment
• /
• v.20 no.6
• /
• pp.55-61
• /
• 2015

Based on the literature study for the determination of perchlorate in soil we chose the ion chromatography as a measurement method and decided to use 70 mM KOH as an eluent to avoid the interference derived from the co-elution of pyrophosphate (P₂O₇⁴⁻), tripolyphosphate (P₃O₁₀⁵⁻). Also we proposed to use air dried soil through 0.15 mm sieve and distilled water as an extractant. Under the these basic concepts, we carried out the experiments to set up the detail procedure like solid to liquid ratio (S/L ratio), extraction time, device for extraction and indicating factors for quality control (e.g. precision, accuracy, MDL, LOQ). In case of time and device for extraction, 5 hours of mechanical shaking or 1 hour of centrifugation showed better precision and accuracy than that of sonication for 1 hour According to these results, we proposed the extraction method combining 5 hours of mechanical shaking with 1 hour of centrifugation. From the aspect of S/L ratio, the ratio of 1/2 or 1/3 showed resonable precision and accuracy. In case of the ratio of 1/2, there would be some problems in the separation process when the proportion of fine particle is high. Therefore, we proposed the extraction ratio of solid to liquid as 1/3 instead of 1/2. With the consideration of cost effectiveness and soil salinity, we proposed the use of cartridge for removing the interfering anions like chloride, sulfate and carbonate in specific sample such as saline soil.

• Journal of Chest Surgery
• /
• v.31 no.6
• /
• pp.598-603
• /
• 1998

Excessive sweating of the palms, axillae, and face has a strong negative impact on the quality of life for many people. The existing non-operative therapeutic options seldom give sufficient relief and have a transient effect. But a definitive cure can be obtained by upper thoracic sympathectomy. From June 1997 to October 1997, 117 cases of the needle (2 mm) thoracoscopic thoracic sympathectomies were performed in the Department of Thoracic and Cardiovascular Surgery in the Respiratory Center Yong-dong Severance Hospital in Seoul, Korea. We have followed up on 94 cases which include palmar hyperhidrosis (n=85), facial hyperhidrosis(n=5) and axillary hyperhidrosis(n=4). There were 42 males and 52 females whose ages ranged from 14 to 63 years(median:23 years). The T2 ganglia and T3-4 ganglia were excised by electrocuting with a hook and endoscissors and were removed for histologic examination. There have been no mortalities or life-threatening complications. The surgical results were classified as excellent(much improvement,very dry) in 93.6%, good(some improvement, minimally wet) in 2.1%, and fair(slight improvement, still wet) in 4.2%. Five patients(5.3%) required closed thoracostomy drainage because of pneumothorax in the immediate postoperative day. Horner's syndrome occurred in one case. The compensatory sweating occurred in 67 cases(71.2%) and was embarrassing in 21 cases(22.3%) and disabling in 9 cases(9.6%) of these cases. Primary failure occurred in one case. The patient with primary failure underwent successful operation. Fifty-one patients had concomitant hyperhidrosis. Our experiences indicate needle thoracoscopic sympathectomy is a very effective, safe, and time- saving procedure for essential hyperhidrosis.

• Journal of Intelligence and Information Systems
• /
• v.9 no.1
• /
• pp.227-249
• /
• 2003

Prediction of corporate failure using past financial data is a well-documented topic. Early studies of bankruptcy prediction used statistical techniques such as multiple discriminant analysis, logit and probit. Recently, however, numerous studies have demonstrated that artificial intelligence such as neural networks can be an alternative methodology for classification problems to which traditional statistical methods have long been applied. In building neural network model, the selection of independent and dependent variables should be approached with great care and should be treated as model construction process. Irrespective of the efficiency of a teaming procedure in terms of convergence, generalization and stability, the ultimate performance of the estimator will depend on the relevance of the selected input variables and the quality of the data used. Approaches developed in statistical methods such as correlation analysis and stepwise selection method are often very useful. These methods, however, may not be the optimal ones for the development of neural network model. In this paper, we propose a genetic algorithms approach to find an optimal or near optimal input variables fur neural network modeling. The proposed approach is demonstrated by applications to bankruptcy prediction modeling. Our experimental results show that this approach increases overall classification accuracy rate significantly.

• Reproductive and Developmental Biology
• /
• v.35 no.1
• /
• pp.123-129
• /
• 2011

The pig has been considered to serve as an appropriate model of human disease. Therefore, establishment of porcine embryonic stem cell lines is important. The purpose of the present study was to further work in this direction. We produced porcine parthenogenetic embryos, and separately aggregated two of each of two-cell ($2{\times}2$), four-cell ($2{\times}4$), and eight-cell ($2{\times}8$) embryos derived by parthenogenesis. After culture for 4 days, the developmental ability of the aggregates and total blastocyst cell numbers were evaluated. The percentage of blastocysts was significantly higher in both $2{\times}4$- and $2{\times}8$-aggregated embryos ($58.3{\pm}1.9%$ and $37.2{\pm}2.8%$, respectively) than in the control or $2{\times}2$-aggregated embryos ($23.6{\pm}1.1%$ and $12.5{\pm}2.4%$, respectively). Total blastocyst cell numbers were increased in the $2{\times}4$- and $2{\times}8$-aggregated embryos (by $44{\pm}3.0%$ and $45{\pm}3.3%$, respectively) compared with those of control or $2{\times}2$-aggregated embryos ($30.5{\pm}2.1%$ and $30.7{\pm}2.6%$, respectively; p<0.05). The levels of mRNA encoding Oct-4 were higher in both the $2{\times}4$- and $2{\times}8$-aggregated embryos than in the control. When blastocysts derived from $2{\times}4$- aggregated embryos or intact normal embryos were cultured on mouse embryonic fibroblast feeder cells to obtain porcine stem cells, blastocysts from aggregated embryos formed colonies that were better in shape compared with those derived from intact blastocysts. Together, the data show that aggregation of porcine embryos not only improves blastocyst quality but also serves as an efficient procedure by which porcine embryonic stem cells can become established.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• autumn
• /
• pp.539-542
• /
• 2002

Crack sealing is a maintenance procedure that is commonly used to reduce pavement degradation. If cracks in pavements are not sealed, surface water penetration can reduce the strength of the sub-base layers, which can result in increased deflections of the pavement. Reduced strength of the sub-base also accelerates the deterioration of the surface, due to development of greater cracking and potholes. Crack sealing is performed to reduce water and debris penetration, thereby helping to maintain pavement structural capacity and limiting future degradation. The process of sealing cracks in pavements is however dangerous, costly, and labor-intensive operation. Labor turnover and training are increasing problems related to crack sealing crews, and as traffic volumes increase. Automating crack sealing can reduce labor and road user costs, improve work quality, and decrease worker exposure to roadway hazards. The main objective of this research is to develop an automated system for sealing cracks in pavement. Extension of the algorithms and tools presented in this research is also recommended for future study.

• Journal of KIISE:Computer Systems and Theory
• /
• v.32 no.1
• /
• pp.29-38
• /
• 2005

The fluid animation procedure consists of physical simulation and visual rendering. In the physical simulation of fluids, the most frequently used practices are the numerical simulation of fluid particles using particle dynamics equations and the continuum analysis of flow via Wavier-Stokes equation. Particle dynamics method is fast in calculation, but the resulting fluid motion is conditionally unrealistic The method using Wavier-Stokes equation, on the contrary, yields lifelike fluid motion when properly conditioned, yet the complexity of calculation restrains this method from being used in real-time applications. Global illumination is generally successful in producing premium-Duality rendered images, but is also excessively slow for real-time applications. In this paper, we propose a rapid fluid animation method incorporating enhanced particle dynamics simulation method and pre-integrated volume rendering technique. The particle dynamics simulation of fluid flow was conducted in real-time using Lennard-Jones model, and the computation efficiency was enhanced such that a small number of particles can represent a significant volume. For real-time rendering, pre-integrated volume rendering method was used so that fewer slices than ever can construct seamless inter-laminar shades. The proposed method could successfully simulate and render the fluid motion in real time at an acceptable speed and visual quality.