• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.11
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• pp.1123-1129
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• 2010

Angular Deviation(AD) on transparency applied to TA-50 Aircraft deteriorates armament system's accuracy because it makes a difference in between actual and theoretical targets. In order to increase accuracy, therefore, TA-50 Aircraft measures AD on transparency and provide the measured values for the integrated mission display computer as a type of AD coefficients. This makes AD revised so that pilots can accurately see the actual target on their head-up display. In order to implement such mechanism into a real field, we develop a new device and system automatically measuring AD for the first time. We also deal with basic concept including AD induction formula as well as operating systems. As a consequence of testing the accuracy and precision for verifying reliability of the system, we got satisfactory results. In specific, the accuracy was within the resultant criterion of 1%. The precision was also satisfied with respect to the whole criteria. The system developed through this research is qualified as a military standard equipment for transparency of the canopy.

• Korean Journal of Food Science and Technology
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• v.52 no.3
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• pp.310-315
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• 2020

The aim of this study was to investigate the texture change of cooked rice within a short time after cooking. Using four instant rice brands, the texture change within 30 min after cooking was measured by the texture profile analysis (TPA) method for hardness, adhesiveness, cohesiveness, chewiness, and springiness with different compression ratios (30, 70%) and cross-head speeds (0.5, 1.0 mm/s). In the case of cohesiveness, adhesiveness, and chewiness, there were significant differences in the rice textures at 20 to 30 min after cooking compared to that in the sample immediately after cooking. In particular, adhesiveness showed significant differences at 10 min after cooking. However, there were little significant differences within 30 min for springiness. In conclusion, when measuring cooked rice texture, it is desirable to measure it, if possible, within 10 to 20 min after cooking.

• Bulletin of the Korean Chemical Society
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• v.34 no.11
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• pp.3307-3311
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• 2013

A new fiber optical sensor was developed for the determination of 2,4-dichlorophenol (DCP). The sensor was based on DCP oxidation by oxygen with the catalysis of iron(III) tetrasulfophthalocyanine (Fe(III)PcTs). The optical oxygen sensing film with $Ru(bpy)_3Cl_2$ as the fluorescence indicator was used to determine the consumption of oxygen in solution. A lock-in amplifier was used for detecting the lifetime of the oxygen sensing film by measuring the phase delay change of the sensor head. The different variables affecting the sensor performance were evaluated and optimized. Under the optimal conditions (i.e. pH 6.0, $25^{\circ}C$, Fe(III)PcTs concentration of 0.62 mg/mL), the linear detection range and response time of the sensor are $1.0{\times}10^{-6}-9.0{\times}10^{-6}$ mol/L and 250 s, respectively. The sensor displays high selectivity, good repeatability and stability, and can be used as an effective tool in analyzing DCP concentration in practical samples.

• Restorative Dentistry and Endodontics
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• v.17 no.2
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• pp.331-341
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• 1992

The purpose of this study was to measure the polymerization contraction stress of two types of composite resins; chemical cured type(Cliarfil F II, Kuraray, Japan) and photo-cured type(Photo-Clearfil Bright, Kuraray, Japan). The stresses of composite resin by contraction measured with specially designed measuring device(Fig. 1). The stresses caused by shrinkage during hardening of specimens were measured according to the type of composite resins, thickness of specimen(0.65, 1.30 and 1.95mm), and ratio of catalyst to base in case of only chemical cured composite resin(0.5, 1.0 and 1.5). As the composite resin specimen shrank on hardening, the load cell recorded force vs time automatically on pen-recorder(Toa, Japan) with a cross-head speed 60mm/hr at 0~10 voltages up to 2 hours. The experiments were conducted in a room maintained at $23{\pm}2^{\circ}C$ and relative humidity $50{\pm}10%$. The results were as follows. 1. The contraction stress during hardening was higher in photo cured composite resin than in chemical cured composite resin. 2. The contraction stress during hardening was increased with thickness of composite resin specimen. 3. In chemical cured composite resin, the polymerization contraction stress was decreased with ratio of catalyst and base. 4. The contraction stress during polymerization was higher in early time after insertion of photo cured composite resin and chemical cured composite resin.

• Restorative Dentistry and Endodontics
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• v.17 no.2
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• pp.383-397
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• 1992

The purpose of this study was to evaluate the influence of artificial saliva contamination on bonding of several dentin adhesives to dentin. Sixty - three human molar teeth extracted within a month were used. Each tooth was sectioned longitudinally in a buccolingual direction to obtain 126 specimens. These specimens were randomly divided into three groups and were treated by Scotchbond 2, Gluma and All bond. Each group was subdivided into three subgroups; normal group not contaminated with artificial saliva, contaminated with artificial saliva and dried group, and contaminated with artificial saliva and washed and dried group. Enamel/dentin bonding agent(Dental Adhesive of Scotchbond 2) was applied and light cured on the treated dentin surfaces. Thereafter P - 50 were cured on them, and specimens were stored in $37^{\circ}C$ artificial saliva for 24 hours before measuring shear bond strength. Shear bond strengths were determined using an universal testing machine with cross head speed 1mm/min and SEM examinations were conducted to evaluate the resin - dentin interface and degree of penetrating resin string into the dentinal tubules. The following results were obtained. 1. Normal groups not contaminated with artificial saliva showed greater shear bond strength than any other group contaminated with artificial saliva(P<0.01). 2. The shear bond strengths showed no significant difference between washed groups with distilled water and not washed groups after contamination with artificial saliva(P>0.05). 3. In normal groups, the shear bond strength of A group was significantly greater than in any other group(P<0.01). 4. In Sand G groups, fractures after shear bond strength tests occured adhesively on resintooth interface in all specimens. But in A groups, fracture of the normal group occured cohesively in dentin and fracture of the contaminated groups occured adhesively and cohesively. 5. On SEM examination, the number of resin strings penetrated into dentinal tubules were the greatest in normal groups, followed by, in descending order, washed groups and not washed groups after contamination with artificial saliva.

• Fire Science and Engineering
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• v.33 no.5
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• pp.13-18
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• 2019

In this study, the soot formation characteristics of Jet-A1 liquid fuel droplet flames were investigated by measuring the soot concentration under atmospheric conditions similar to the working environment of the Korea Space Launch Vehicle (KSLV) To obtain the desired atmospheric conditions, the oxygen concentration in the combustion chamber was maintained at 30% and the pressure was varied between 0.1 and 0.06 MPa. The full-field light extinction technique was used to measure the concentration of soot particles generated by applying the identical to 2-mm-diameter Jet-A1 fuel droplets. The soot concentration of the Jet-A1 droplet flames was the highest in the nitrogen-substituted atmosphere and the lowest in the carbon dioxide-substituted atmosphere, despite the pressure. the pressure was decreased the measured soot concentrations reduced as a function of Pⁿ.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.21 no.3
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• pp.226-234
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• 2014

Purpose: This study was done to present guidelines for deciding appropriate times for measuring blood pressure (BP) in patients with neurological disorders who had surgery due to brain damage. Method: It was a repeated measures-experimental research on time variants in BP after nursing care. SBP (Systolic BP) and DBP (Diastolic) were measured every 2 minutes up to 5 times using an EKG patient monitor. Measured data were analyzed using repeated measures ANOVA and paired t-test. Results: For suctioning, there were significantly higher differences for SBP averages after 2 min. (138mmHg, p<0.01) and 4 min. (133mmHg, p<0.01) compared to before suctioning (120mmHg). For position change, there were significant differences in SBP averages after 2 min. (136mmHg, p<0.01) and 4 min. (130mmHg, p=0.01) compared to before changing position (121mmHg). For position change followed by suctioning there were significant differences in SBP averages after 2 min. (136mmHg, p<0.01), 4 min. (136mmHg, p<0.01) and 6 min. (125mmHg, p=0.003) compared to before the interventions (121mmHg). Conclusions: Results indicate that there are significant differences in SBP and DBP over time during nursing interventions, suggesting clinical measurement of BP after 6 min. or 8 min. be done for patients with neurological disorders in neurosurgery clinics.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.39
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• pp.23.1-23.8
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• 2017

Background: The aim of this study is to validate a new three-dimensional craniofacial stereophotogrammetry imaging system (3dMDface) through comparison with manual facial surface anthropometry. The null hypothesis was that there is no difference between craniofacial measurements using anthropometry vs. the 3dMDface system. Methods: Facial images using the new 3dMDface system were taken from six randomly selected subjects, sitting in natural head position, on six separate occasions each 1 week apart, repeated twice at each sitting. Exclusion criteria were excess facial hair, facial piercings and undergoing current dentofacial treatment. 3dMDvultus software allowed facial landmarks to be marked and measurements recorded. The same measurements were taken using manual anthropometry, using soluble eyeliner to pinpoint landmarks, and sliding and spreading callipers and measuring tape to measure distances. The setting for the investigation was a dental teaching hospital and regional (secondary and tertiary care) cleft centre. The main outcome measure was comparison of the craniofacial measurements using the two aforementioned techniques. Results: The results showed good agreement between craniofacial measurements using the 3dMDface system compared with manual anthropometry. For all measurements, except chin height and labial fissure width, there was a greater variability with the manual method compared to 3D assessment. Overall, there was a significantly greater variability in manual compared with 3D assessments (p < 0.02). Conclusions: The 3dMDface system is validated for craniofacial measurements.

• Journal of Magnetics
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• v.21 no.2
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• pp.266-272
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• 2016

Transcranial magnetic stimulation devices has been used mainly for diagnostic purposes by measuring the functions of the nervous system rather than for treatment purposes, and has a problem of considerable energy fluctuations per repeated pulse. The majority of strokes are caused by ischemia and result in brain tissue damage, leading to problems of the central nervous system including hemiparesis, dysfunction of language and consciousness, and dysfunction of perception. Control is difficult and the size is large due to the difficulty of digitalizing the energy stored in a capacitor, and there are many heavy devices. In addition, there are many constraints when it is used for a range of purposes such as head and neck diagnosis, treatment and rehabilitation of nerve palsy, muscle strengthening, treatment of urinary incontinence etc. Output stabilization and minimization of the energy variation rate are required as the level of the transcranial magnetic stimulation device is dramatically improved and the demand for therapeutic purposes increases. This study developed a compact, low cost transcranial magnetic stimulation device with minimal energy variation of a high repeated pulse and output stabilization using a real time capacitor charge discharge voltage. Ischemia was induced in male SD rats by closing off the common carotid artery for 5 minutes, after which the blood was re-perfused. In the cerebrum, the number of PARP reactive cells after 24 hours significantly decreased (p < 0.05) in the TMS group compared to the GI group. As a result, TMS showed the greatest effect on necrosis-related PARP immuno-reactive cells 24 hours after ischemia, indicating necrosis inhibition, blocking of neural cell death, and protection of neural cells.

• Clinical and Experimental Reproductive Medicine
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• v.24 no.3
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• pp.369-375
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• 1997

Studies were conducted to determine the efficiency of decondensation protocols. Sperm obtained from seven normal donors was immediately washed after liquefaction and then decondensed using the method of West et al. (1989) and my original protocol. My optimized protocol entailed mixing 1 ml aliquots of semen with 4 ml phosphate buffered saline (PBS). Following centrifugation, pellets were resuspended in 1 ml PBS containing 6 mM EDTA. After centrifugation, pellets were resuspended in 1 ml PBS containing 2 mM dithiothreitol at $37^{\circ}C$ for 45 min. Following mixing with 2 ml PBS and centrifugation, pellets were resuspended by vortexing. While vortexing, 5 ml of fixative were gently added. Slide preparation was accomplished using the smear method and it was stored at $4^{\circ}C$. When comparing these protocols, the degree of sperm decondensation and head swelling was monitored by measuring nuclear length, area, perimeter, and degree of roundness using FISH analysis software. Apparent copy number for chromosome 1 and, separately, for the sex chromosomes was determined by FISH using satellite DNA probes for loci DIZ1, DXZ1 and DYZ3. Sperm treated by my decondensation protocol showed significant increases (p<0.05) in length, area, perimeter, and degree of roundness. There was a significant decrease (p<0.05) in the frequency of nuclei displaying no signal but no change in the frequency of nuclei with two signals in samples decondensed by my protocol. My data suggested that decondensation using my original protocol may lower the frequency of cells with spurious "nullisomy" due to hybridization failure without inducing spurious "disomy" resulting from increased distances between split signals.