• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.4
• /
• pp.538-544
• /
• 2021

Technology readiness assessment is a procedure for managing defense project risk factors based on the preemptive identification of technical risks. Under current regulations, technology readiness is determined based on considerations of the ratings of factors itemized on a checklist, whether unsatisfied factors have a fatal impact on the project, and whether countermeasures for unsatisfied factors have been established. However, objective criteria for assessing the impact of unsatisfied factors have not been presented, and thus, at present, the results of technology readiness level determinations are largely subjective. In addition, the importance of questions on the checklist is dependent on individual project characteristics and this is not considered during the assessment process. In this paper, we propose an improved technology readiness assessment procedure that considers the characteristics of each project. Using the proposed procedure, we quantitatively determined the importance of each checklist item using a weighting method. We found the devised procedure improved the reliability and objectivity of technology readiness assessment results. A case analysis of a complex weapons system is presented to demonstrate these improvements.

• Journal of The Korean Society of Clinical Toxicology
• /
• v.12 no.1
• /
• pp.14-21
• /
• 2014

Purpose: The objective of this study was to develop a new scoring tool that is comprehensively applicable and predicts fatality within 24 h of intoxication. Methods: This was a cohort study conducted in two emergency medical centers from 2011 to 2012. We identified factors associated with severe/fatality. Through a discriminant analysis, we devised the aBIG (age, Base deficit, Infection, and Glasgow coma scale) score. To compare the ability of aBIG to predict intoxication severity with that of previous scoring systems such as APACHE II, MODS, SAPS IIe, and SOFA, we determined the receiver operating characteristic curves of each variable in predicting severe-to-fatal toxicity. Results: Compared with the mild/moderate toxicity group (n=211), the severe/fatal group (n=143) had higher incidences of metabolic acidosis, infection, serious mental change, QTc prolongation and hepato-renal failure. Age, base deficit, infection-WBC count, and Glasgow Coma Scale were independently associated with severe/fatal poisoning. These variables were combined into the poisoning "aBIG" score [$0.28{\times}$Age group+$0.38{\times}WBC$ count/$10^3+0.52{\times}$Base deficit+$0.64{\times}$(15-GCS)], which were each calculated to have an area under the curve of 0.904 (95% confidence interval: 0.868-0.933). The aBIG poisoning score had an equivalent level of severity predictability as APACHE II and a superior than MODS, SOFA, and SAPS IIe. Conclusion: We developed a simplified scoring system using the four variables of age, base deficit, infected leukocytosis, and GCS. The poisoning aBIG score was a simple method that could be performed rapidly on admission to evaluate severity of illness and predict fatal severity in patients with acute intoxications.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
• /
• v.22 no.1
• /
• pp.29-37
• /
• 1992

The temporomandibular joint was evaluated using magnetic resonance imaging using a urface coil in 11 patients having reciprocal clicking or locking and compared with the normal joint in five subjects. Serial multisection 3㎜-thick parasagittal, paracoronal, and axial image on both closing and opening mouth were obtained with a 1.5 Tesla MR system and surface coil using CSMEMP, GRASS, MPGR, powerful extensions of fast imaging that is currently under clinical evaluation. MR images obtained were analized correlating with the theory of internal derangement. The obtained results were as follows: 1. The serial findings of structures in joint were determined on the serially sectioned images of joint with reciprocal clicking or locking by CSMEMP and MPGR on closing mouth. 2. The delta shaped white images of synovial fluid in the glenoid fossa and on the posterior surface of condyle were revealed on the parasagittal images by MPGR on opening mouth as in the normal joints. 3. The white image of joint fluid surrounding meniscus was recognized on the paracoronal image by GRASS on opening mouth as in the normal joints. 4. In joints having temporomandibular dysfunction the smooth image of displaced meniscus was recognized, but otherwise in the normal joints the image of muscle was noted on the paracoronal image sectioned at the anterior portion of condyle by GRASS. 5. The more thickened fascial plane between superior and inferior belly of lateral pterygoid muscle was not recognizable in joints having temporomandibular dysfunction than in the normal joints.

• Journal of Environmental Science International
• /
• v.10 no.4
• /
• pp.287-292
• /
• 2001

A packed bed of volcanic rock was used as deodorizing material to remove hydrogen sulfide($H_2$S) from air in a laboratory-scale column, and was inoculated with Thiobacillus sp. as $H_2S$ oxidizer. The effects of volcanic rock particle size distribution on system pressure drop were examined. Various tests have been conducted to evaluate the effect of $H_2S$ inlet concentration and CBCT(Empty Bed Contact Time) on $H_2S$ elimination. The pressure drop for particles of size range from 5.6 to 10 mm was 14 mm$H_2S$/m at a representative gas velocity of 0.25m/s. Biofilter using scoria and Thiobacillus sp. could get the stable removal efficiencies more than 99.9% under $H_2S$ inlet concentrations in the range from 30 to 1,100ppm at a constant gas flow rate of $15.2{\ell}$/min. $H_2S$ removal efficiencies greater than 99% were observed as long as EBCT was longer than 8sec at the 250ppm of $H_2S$ inlet concentration. When EBCT was reduced to 5.5 sec, $H_2S$ removal efficiency decreased by about 12 percent. The maximum $H_2S$ elimination capacity was determined to be 269g-$H_2S/m^3{\cdot}hr$.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.39 no.1
• /
• pp.111-115
• /
• 2015

In injection molding process using hot runners, color change is a critical issue. This work proposes a method of assessing the color change characteristics of thermoplastics polymers. A method that utilizes a capillary die to measure degree of color change has been devised and implemented. The extrudate from the capillary die has been imaged and quantized to a gray scale value. Based on the gray scale value, the degree of color change has been determined. Under given temperatures and extrusion velocity, its trend along with the number of extrusion has been obtained and analyzed.

• Bulletin of the Korean Chemical Society
• /
• v.31 no.7
• /
• pp.1907-1914
• /
• 2010

A novel catalytic kinetic method is proposed for the determination of Se(IV), Se(VI) and total inorganic selenium in water based on the catalytic effect of Se(IV) on the reduction of bromate by p-nitrophenylhydrazine at pH 3.0. The generated bromine, $Br_2$ or $Cl_2$ plus $Br_2$ in 0.1 M NaCl (or NaBr) environment efficiently decolorized Calmagite and the reaction was monitored spectrophotometrically at 523 nm as a function of time. In this indicator reaction, bromide acted as an activator for the catalysis of selenium (IV) and a reducing agent for selenium (VI) at pH 3.0, which allowed the determination of total selenium. The fixed time method was adopted for the determination and speciation of inorganic selenium. Under the optimum conditions, the calibration graph are linear in the range 1 - 35 ${\mu}gL^{-1}$ of Se(IV) for the fixed time method at $25^{\circ}C$. The detection limit based on statistical $3S_{blank}$/m-criterion was 0.215 ${\mu}gL^{-1}$ for the fixed time method (7 min). All of the variables that affect the sensitivity at 523 nm were investigated, and the optimum conditions were established. The interference effect of various cations and anions on the Se (IV) determination was also studied. The selectivity of the selenium determination was greatly improved with the use of the strongly cation exchange resin such as Amberlite IR120 plus. The proposed kinetic method was validated statistically and through recovery studies in natural water samples. The RSDs for ten replicate measurements of 5, 15 and 25 ${\mu}gL^{-1}$ of Se(IV) and Se(VI) was changed between 2.1 - 4.85%. Analyses of a certified standard reference material (NIST SRM 1643e) for selenium using the fixed-time method showed that the proposed kinetic method has good accuracy. Se(IV), Se(VI) and total inorganic selenium in environmental water samples have been successfully determined by this method after selective reduction of Se(VI) to Se(IV).

• Fashion & Textile Research Journal
• /
• v.20 no.3
• /
• pp.323-330
• /
• 2018

This study aim is to provide new coloration method by laccase-catalyzation on natural phenolic dyeing process. In this study, silk was dyed with black tea, which is one of polyphenolic dye, extracted in distilled water. The dyed samples were catalyzed by laccase as the eco-friendly mordanting process. To optimize the conditions of laccase-catalyzed coloration, conditions were varied by different mordanting methods (one-bath, two-bath), temperature and treatment time. The dye affinity in terms of the value of K/S, $L^*$, $a^*$, $b^*$, and H, V, C was measured by Computer Color Matching System (CCM, CM-2600d, Spectra Magic NX, Korea). The effect of laccase-catalyzed coloration on washing fastness was evaluated and compared with the synthetic mordant (Al, Cu, and Fe). As the result of color analysis of dyed silk, the optimum conditions of laccase-catalyzed coloration were determined to post-mordanting by one-bath at $50^{\circ}C$ for 3 hours. Under the optimum laccase-catalyzed conditions, the dyed silk was shown the color of yellowish-red. After laccase-catalyzed coloration on the dyed silk, the improvement of washing fastness was obtained compared with mordanted silk by synthetic mordant (Al, Cu, and Fe). Therefore, the present study was demonstrated that the effective enzymatic mordanting method by laccase for phenolic natural dyeing with vivid color and good fastness.

• The Korean Journal of Physiology and Pharmacology
• /
• v.19 no.2
• /
• pp.111-118
• /
• 2015

Osteoprotegerin (OPG), receptor activator of NF-${\kappa}B$ ligand (RANKL)/receptor activator of NF-${\kappa}B$ (RANK) axis, and TNF-related apoptosis-inducing ligand (TRAIL) participate in vascular calcification process including atherosclerosis, but their contributions under high glucose (HG) and phosphate (HP) condition for a long-term period (more than 2 weeks) have not been fully determined. In this study, we evaluated the effects of HG and HP levels over 2 or 4 weeks on the progression of vascular calcification in rat vascular smooth muscle cells (VSMCs). Calcium deposition in VSMCs was increased in medium containing HG (30 mmol/L D-glucose) with ${\beta}$-glycerophosphate (${\beta}$-GP, 12 mmol/L) after 2 weeks and increased further after 4 weeks. OPG mRNA and protein expressions were unchanged in HG group with or without ${\beta}$-GP after 2 weeks. However, after 4 weeks, OPG mRNA and protein expressions were significantly lower in HG group with ${\beta}$-GP. No significant expression changes were observed in RANKL, RANK, or TRAIL during the experiment. After 4 weeks of treatment in HG group containing ${\beta}$-GP and rhBMP-7, an inhibitor of vascular calcification, OPG expressions were maintained. Furthermore, mRNA expression of alkaline phosphatase (ALP), a marker of vascular mineralization, was lower in the presence of rhBMP-7. These results suggest that low OPG levels after long term HG and phosphate stimulation might reduce the binding of OPG to RANKL and TRAIL, and these changes could increase osteo-inductive VSMC differentiation, especially vascular mineralization reflected by increased ALP activity during vascular calcification.

• Journal of the Korean Chemical Society
• /
• v.46 no.3
• /
• pp.233-240
• /
• 2002

In this work, the cure kinetics and rheological and mechanical properties of diglycidylether of bispheonol A (DGEBA, EP)/polyurethane (PU) blends were investigated. The 1 wt% N-benzylpyrazinium hexafluoroantiminate (BPH) was used as a latent thermal catalyst. Latent properties were performed by measurement of the conversion as a function of reaction temperature using DSC. And the rheological properties of the blend systems were investigated under isothermal conditions using a rheometer. Crosslinking activating energies (Ec) were also determined from the Arrhenius equation based on gel time and curing temperature. The impact strengths were measured as mechanical properties of the casting specimens. The BPH in the blend systems could be an excellent latent thermal catalyst without any co-initiator. The rheological results showed that Ec was highest when PU content was 30 wt% which was in good agreement with the impact strengths. This was probably due to the intermolecular hydrogen bonding between the hydroxyl group in PU and EP, resulting in increasing the crosslinking density.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.40 no.1
• /
• pp.69-76
• /
• 1995

Cold acclimation involves changes in gene expression. BN28 and BN115 are two genes which are regulated by cold temperature and assumed having roles in cold acclimation. The objectives of this experiment was to explore the expression of BN28 and BN115 under field conditions. Six winter cultivars were planted at three different dates during the fall. The expression of the genes was determined by northern blot analysis of total RNA taken from leaves 15 to 30 day-intervals after planting. The expression of the two genes was detected within 15 days after planting well before onset of freezing tolerance in plants. This suggestes either their expression was a prerequisite of the freezing tolerance or their expression was regulated by other environmental factors as well as temperature. Two genes showed a different expression pattern suggesting they had a different regulatory system. Although timecourse increase in expression of the cold-regulated genes was matched with increase in freezing tolerance, the difference of expression in cultivar level at specific times of measurement was not correlated with freezing tolerance at the moment.