• Journal of Korean Society of Transportation
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• v.27 no.6
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• pp.29-44
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• 2009

A variety of research efforts, using advanced wireless communication technologies, have been made to develop more reliable traffic information system. This study presents a novel decentralized traffic information system based on vehicle infrastructure integration (VII). A major objective of this study was also to devise a methodology for determining appropriate spacing of roadside equipment (RSE) to fully exploit the benefits of the proposed VII-based traffic information system. Evaluation of travel time estimation accuracy was conducted with various RSE spacings and the market penetration rates of equipped vehicle. A microscopic traffic simulator, VISSIM, was used to obtain individual vehicle travel information for the evaluation. In addition, the ANOVA tests were conducted to draw statistically significant results of simulation analyses in determining the RSE spacing. It is expected that the proposed methodology will be a valuable precursor to implementing capability-enhanced next generation traffic information systems under the forthcoming ubiquitous transportation environment.

• Journal of Veterinary Clinics
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• v.28 no.2
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• pp.258-261
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• 2011

An 8-year-old spayed female, Yorkshire terrier dog was presented with a urinary incontinence. Unaware urine dribbling during sleeping was observed eight months after spaying. Polyuria and polydipsia were also reported. Physical examination revealed obesity and hypertension. Characteristic laboratory findings in this dog were polycythemia, hyperlipidemia and elevated hepatic enzyme. Other causes of the urinary incontinence were ruled out through further diagnostic tests and spay-related urethral sphincter mechanism incompetence (USMI) was made as a presumptive diagnosis. In addition, the dog was also diagnosed with pituitary-dependent hyperadrenocorticism. Both conditions can cause urinary incontinence in dogs; therefore, definite diagnosis was made through a therapeutic approach. The synthetic estrogen, diethylstilbesterol, was initially administered and successfully managed the urinary incontinence in this dog. To the best of the author's knowledge, this is the first case report describing the clinical and laboratory features of spay-related USMI concurrent with hyperadrenocorticism and treatment outcomes in our country.

• Toxicological Research
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• v.34 no.3
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• pp.191-197
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• 2018

In 2015, a candidate for the second national reference standard (NRS) of Gloydius snake venom was produced to replace the first NRS of Gloydius snake venom. In the present study, the potencies of the candidate were determined by a collaborative study, and the qualification of the candidate was estimated. The potencies of the candidate were determined by measuring the murine lethal titers and lapine hemorrhagic titers of venom against the regional working reference standard (RWRS) for antivenom using the methods described in the previous report for the first NRS of Gloydius snake venom. Three Korean facilities contributed data from a total of 30 independent assays. Subsequently, two foreign national control research laboratories contributed to this collaborative study. The results were calculated using the Reed-Muench method for lethality and determined using a mixed-effects model for hemorrhage. The general common potencies of the lethal and hemorrhagic titers were obtained from the results of the 30 tests performed at three Korean facilities. The results are expressed in micrograms for 1 test dose (TD) with a 95% confidence interval as follows: a lethal titer of $90.13{\mu}g/TD$ (95% confidence interval = $87.39{\sim}92.86{\mu}g$) and a hemorrhagic titer of $10.80{\mu}g/TD$ (95% confidence interval = $10.46{\sim}11.14{\mu}g$). In addition, the candidate preparation showed good quality evaluation according to the results of the quality estimation of the candidate and is judged to be suitable to serve as the Korean NRS for snake venom. In conclusion, the second NRS of Gloydius snake venom was established in this study and will be used for national quality control, including a national lot release test of Korean antivenom products.

• Biomolecules & Therapeutics
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• v.21 no.4
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• pp.299-306
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• 2013

In the present study, we investigated the effect of ethanolic extract of the seed of Zizyphus jujuba var. spinosa (EEZS) on cholinergic blockade-induced memory impairment in mice. Male ICR mice were treated with EEZS. The behavioral tests were conducted using the passive avoidance, the Y-maze, and the Morris water maze tasks. EEZS (100 or 200 mg/kg, p.o.) significantly ameliorated the scopolamine-induced cognitive impairment in our present behavioral tasks without changes of locomotor activity. The ameliorating effect of EEZS on scopolamine-induced memory impairment was significantly reversed by a sub-effective dose of MK-801 (0.0125 mg/kg, s.c.). In addition, single administration of EEZS in normal naive mouse enhanced latency time in the passive avoidance task. Western blot analysis was employed to confirm the mechanism of memory-ameliorating effect of EEZS. Administration of EEZS (200 mg/kg) increased the level of memory-related signaling molecules, including phosphorylation of extracellular signal-regulated kinase or cAMP response element-binding protein in the hippocampal region. Also, the time-dependent expression level of brain-derived neurotrophic factor by the administration of EEZS was markedly increased from 3 to 9 h. These results suggest that EEZS has memory-ameliorating effect on scopolamine-induced cognitive impairment, which is mediated by the enhancement of the cholinergic neurotransmitter system, in part, via NMDA receptor signaling, and that EEZS would be useful agent against cognitive dysfunction such as Alzheimer's disease.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.6
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• pp.565-571
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• 2016

This paper investigates macro- and microscopic fractography performed on fracture specimens from low cycle fatigue (LCF) testings through an Alloy 617 base metal and weldments. The weldment specimens were taken from gas tungsten arc welding (GTAW) pad of Alloy 617. The aim of the present study is to investigate the macro- and microscopic aspects of the low cycle fatigue fracture mode and mechanism of Alloy 617 base metal and GTAWed weldment specimens. Fully axial total strain controlled fatigue tests were conducted at room temperature with total strain ranges of 0.6, 0.9, 1.2 and 1.5%. Macroscopic fracture surfaces of Alloy 617 base metal specimens showed a flat type normal to the fatigue loading direction, whereas the GTAWed weldment specimens were of a shear/star type. The fracture surfaces of both the base metal and weldment specimens revealed obvious fatigue striations at the crack propagation regime. In addition, the fatigue crack mechanism of the base metal showed a transgranular normal to fatigue loading direction; however, the GTAWed weldment specimens showed a transgranular at approximately $45^{\circ}$ to the fatigue loading direction.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.7
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• pp.683-689
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• 2017

We have carried out the development for hydraulic breaker which can be operated by optimal mode with ICT convergence technology. This developed system can predict the rock properties. Moreover, this system can maximize the energy efficient with intelligent control of hydraulic system. In order to provide the optimal impact force, this system can measure the descending depth of piston with the proximity sensor and discriminate the rock properties with the measuring data and control the piston stroke using solenoid valve eventually. In addition, we have developed the controller, display module and operating device for cascade (multi-level impact) system and applied the module which can communicate each system by wireless communications. In conclusion, the control system which can control the multi-level impact in accordance with strength of rocks has been developed and approved by several field tests.

• Journal of the Korean Society for Nondestructive Testing
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• v.36 no.6
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• pp.443-450
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• 2016

In this study, we propose a novel fiber optic sensor to show the measurement feasibility of distributed temperature and strains in a single sensing fiber line. Distributed temperature can be measured using optical time domain reflectometry (OTDR) with a Raman anti-Stokes light in the sensing fiber line. Moreover, the strain can be measured by fiber Bragg gratings (FBGs) in the same sensing fiber line. The anti-Stokes Raman back-scattering lights from both ends of the sensing fiber, which consists of a 4 km single mode optical fiber, are acquired and inserted into a newly formulated equation to calculate the temperature. Furthermore, the center wavelengths from the FBGs in the sensing fiber are detected by an optical spectrum analyzer; these are converted to strain values. The initial wavelengths of the FBGs are selected to avoid a cross-talk with the wavelength of the Raman pulsed pump light. Wavelength shifts from a tension test were found to be 0.1 nm, 0.17 nm, 0.29 nm, and 0.00 nm, with corresponding strain values of $85.76{\mu}{\epsilon}$, $145.55{\mu}{\epsilon}$, $247.86{\mu}{\epsilon}$, and $0.00{\mu}{\epsilon}$, respectively. In addition, a 50 m portion of the sensing fiber from $30^{\circ}C$ to $70^{\circ}C$ at $10^{\circ}C$ intervals was used to measure the distributed temperature. In all tests, the temperature measurement accuracy of the proposed sensor was less than $0.50^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.48 no.6
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• pp.560-564
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• 2016

The objective of this study was to investigate the anti-Bacillus cereus activity of actinonin. Actinonin inhibited the growth of B. cereus in a dose dependent manner. The growth-inhibitory activity of actinonin was evaluated using a broth micro-dilution method, and minimum inhibitory concentration (MIC) and agar disk diffusion tests. B. cereus showed high susceptibility to actinonin in a concentration-dependent manner and MIC was determined to be $0.192{\mu}g/mL$. Additionally, 1 and 2 mM actinonin induced formation of B. cereus inhibition zones. In addition, as compared to B. cereus alone, B. cereus added with $10{\mu}M$ actinonin showed a lower level of cytotoxicity in HeLa cells in vitro. Thus, this study revealed that actinonin could be a potential source of a natural antimicrobial agent or a pharmaceutical component against B. cereus.

• Journal of Life Science
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• v.24 no.4
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• pp.437-446
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• 2014

Problems appear when triptans are taken orally. For example, the bioavailability of triptan is reduced by the digestive system, and the drug level in the blood reduces rapidly over time; there is also a possibility of gastrointestinal disorder. To improve side effects, a transdermal patch has been prepared in hydrogel form. The polymer matrix that makes up the hydrogel uses PVA; PEG is used as an additive to induce inter/intra hydrogen bonding of the PVA and almotriptan drug is added. In addition, to accelerate micro-phase separation between PVA chains, liquid nitrogen is used. In FT-IR analysis, the absorption bands of PVA, PEG, and almotriptan were found. The degree of crystallinity, the water uptake ability and tensile strength were increased with increasing PEG content. In drug release tests, the amount of drug released increased depending on the PEG content. In this study, hydrogels with 10 wt% PEG showed better performance in drug release. Approximately 60% of the total drug amount was released in 2 hr, and the drug continued to release for 1 day. Thus, the prepared hydrogel patch is suitable as a transdermal formulation for the second dose administration of triptans to patients who require recurrent migraine treatment within 24 hr after the first administration.

• Applied Chemistry for Engineering
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• v.25 no.2
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• pp.181-187
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• 2014

In order to use the spherical atomizing reduction steel slag (ladle furnace slag, LFS) instead of the fine aggregate of polymer concrete composites, various specimens were prepared with various replacement ratios of atomizing reduction steel slag and the addition ratios of polymer binder. Physical properties of these specimens were investigated through the absorption test, the compressive strength test, the flexural strength test, the hot water resistance test, the pore analysis and the micro-structure using scanning electron microscope. Results showed that the compressive strength and flexural strength of specimens with 7.5% of polymer binders increased with the increase of replacement ratios of atomizing reduction steel slag, but those of the specimens with 8.0% or more of polymer binders showed a maximum strength at a certain replacement ratio due to the material segregation causing the increase of fluidity. By hot water resistance tests, the compressive strength, flexural strength, average pore diameter, and bulk density decreased but the total pore volume and pore diameter increased. It was concluded that the amount of polymer binders could be reduced by maximum 23.8%, because the workability of the polymer concrete was remarkably improved by using the atomizing reduction steel slag instead of fine aggregate. However, since the use of atomizing reduction steel slag decreased the resistance of the polymer concrete to hot water, further studies are required.