• Publications of The Korean Astronomical Society
• /
• v.30 no.2
• /
• pp.121-123
• /
• 2015

We report our measurements of the trigonometric distance and proper motion of IRAS 20056+3350, obtained from the annual parallax of $H_2O$ masers. Our distance of $D=4.69^{+0.65}_{-0.51}kpc$, which is 2.8 times larger than the near kinematic distance adopted in the literature, places IRAS 20056+3350 at the leading tip of the Local arm and proximal to the Solar circle. We estimated the proper motion of IRAS 20056+3350 to be (${\mu}_{\alpha}cos{\delta}$, ${\mu}_{\delta}$) = ($-2.62{\pm}0.33$, $-5.65{\pm}0.52$) $mas\;yr^{-1}$ from the group motion of $H_2O$ masers, and use our results to estimate the angular velocity of Galactic rotation at the Galactocentric distance of the Sun, ${\Omega}_0=29.75{\pm}2.29km\;s^{-1}kpc^{-1}$, which is consistent with the values obtained for other tangent points and Solar circle objects.

• Publications of The Korean Astronomical Society
• /
• v.30 no.2
• /
• pp.115-118
• /
• 2015

We made phase-referencing Very Long Baseline Interferometry (VLBI) observations of Galactic 22 GHz $H_2O$ maser sources with VLBI Exploration of Radio Astrometry (VERA). We measured the parallax distances of G48.61+0.02, G48.99-0.30, G49.19-0.34, ON1, IRAS 20056+3350, IRAS 20143+3634, ON2N, and IRAS 20126+4104, which are located near the tangent point and the Solar circle. The angular velocity of the Galactic rotation at the LSR (i.e. the ratio of the Galactic constants) is derived using the measured parallax distances and proper motions of these sources. The derived value of ${\Omega}_0=28.8{\pm}1.7km\;s^{-1}kpc^{-1}$ is consistent with recent values obtained using VLBI astrometry but 10% larger than the International Astronomical Union (IAU) recommended value of $25.9km\;s^{-1}kpc^{-1}=(220km\;s^{-1})$ / (8.5 kpc).

• Aerospace Engineering and Technology
• /
• v.10 no.2
• /
• pp.65-73
• /
• 2011

After launch, in order to inject the geostationary satellite into its operational orbit, the perigee altitude are forced to be raised to geostationary altitude by firing onboard LAE(Liquid Apogee Engine) at apogee of the transfer orbit. In this process, the LAE burn is divided into three or four separated burns in order to control the orbit very precisely by giving feedback the determined orbit informations and to inject the satellite in predefined longitude. This paper proposes an algorithm to determine LAE firing time slots and ${\Delta}V$ vectors under assumption of impulsive LAE burning, and additionally, a method to compensate errors induced by continuous burning. And computer simulations have been performed to validate proposed algorithms.

• Aerospace Engineering and Technology
• /
• v.12 no.1
• /
• pp.189-199
• /
• 2013

This paper summarizes results of second stage attitude control of KSLV-I third flight test. The results show that three axes attitude control at coasting phases of KSLV-I was successfully accomplished by the reaction control system, and pitch and yaw attitude control at thrusting phase where second stage kick motor burns was also normally accomplished by using the thrust vector control system. It is verified that the second stage controller performed successfully for all flight phases regardless of some disturbances due to mass center offset, slag effects, and residual thrust of kick motor. These results may provide an important basis in enhancing domestic technology level of attitude control of launch vehicle.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• v.20 no.1 s.32
• /
• pp.285-293
• /
• 2007

Burn is a dermal injury mainly caused by heat. It occurs by flame, boiling water or liquid, steam, sparks, chemicals, radiation, and electricity. Burn is classified as four grades depending on how deep into the skin a person is burned. As the deep second-degree burns possibly leave scars, it can have various physical, psychological, and aesthetical effects with seriousness on the patient with a burn. This report is on the 50-year-old female patient who had a burn with boiling water and a mixture condition of superficial and deep second degree burn. The Korean medical treatments such as Herbal acupuncture, Herbal medication, Acupuncture, Herbal-ointment were used for 17 days to treat effectively the patient with a mixture of superficial and deep second degree burn. It is difficult to find out the report that treats a burn with Korean medical treatment. If more clinical treatments as in this report are proved to be effective, we are able to expect that Korean medical treatment should be a good treatment in burn.

• Journal of the Semiconductor & Display Technology
• /
• v.14 no.4
• /
• pp.1-7
• /
• 2015

People are always pursuing the aesthetic feeling relentlessly. But some people have such problems with their hairs like alopecia, cancer chemotherapy, burns, and scalp injury. So the synthetic hair has played a very important role to make up for these deficiencies. But long term use can lead to adverse reactions or uncomfortable feeling. This is primarily caused by its properties differ with human hair. In particular, nanotribological characterizations (roughness, friction force and adhesive force) of synthetic hair surface are dissatisfy with the needs of normal hairs. This paper presents the experiments on nanotribological characterizations measurements of human hairs (coloring hair, permed hair and common hair) in shampooing condition or without shampooing condition. Using atomic force microscopy (AFM) to find out a range of synthetic hair nanotribological characterizations which can correspond with natural hair. The measurements of nanotribological characterizations focus on surface roughness, friction force and adhesive force, and a new design of AFM probe was used for measuring the nanotribological characterizations.

• Journal of muscle and joint health
• /
• v.23 no.1
• /
• pp.28-38
• /
• 2016

Purpose: The purpose of this study was to investigate post-burn itching relevant characteristics in the rehabilitation phase. Methods: Ninety four burn patients who were hospitalized in the rehabilitation phase participated in the study. Self-reported Leuven itch scale-Korean was used to evaluate itching related characteristics. Data were analyzed with descriptive analysis, $x^2$ test, and Kruskal-Wallis test. Results: All subjects except two had the itching. Itching frequency revealed that 68.1% of subjects experienced itching one or more episodes a day or always, and 18.7% had episode durations lasting more than 2 hours per incidence. Mean severity and distress of itching was $5.3{\pm}2.4$ and $5.2{\pm}2.5$, respectively. Itching sensation dimension of tickling was 56.4%. More than 25% of subjects "often" or "always" affected reduced quality of life, loss of concentration, bad mood, and difficulty in falling asleep. Satisfaction with itching treatment was intermediate level. Conclusion: Post-burn itching in the rehabilitation phase was a significant problem despite pruritus treatment. Based on the finding of this study, development of comprehensive and tailored nursing intervention programs for itching could be suggested.

• Journal of the Korean Society of Safety
• /
• v.8 no.4
• /
• pp.165-174
• /
• 1993

For the safety assessment of the demonstration-scale incineration plant for treating the combustible radioactive wastes, radiation doses of a worker and a residential individual were estimated. The demonstration plant showed a good performance of trial-burn tests using non-radioactive tracers with resulting In high mass reduction of around 40 times and very low emmission of dusts through a stack, which promised a high decontamination factor in an order of 10$^{7}$ . Based on the result s obtained from the trial-burns in the process, the estimation of radiation dose for workers and general publics near the plant was made using dose pathway calculation theories. The parametric values for calculation were selected from design and operational results of the process and from more conservative conditions In reference data. The estimated annual doses for workers and residential indivisuals were 3.07 $\times$ 10$^{-4}$ and 4.35 X 10$^{-8}$ $\mu$Sv/y, respectively, which were high enough to operate the process when comparing with the allowable dose limit in the regulation. The dose calculation models were quite applicable with showing an excellent safety for the process.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.1 no.2
• /
• pp.27-33
• /
• 1993

Using the solenoid driven gas injection valve, Hydrogen fuel supply system was made. It was attached to a single cylinder research engine and intake port injection type hydrogen fueled S.I. engine was constructed. Engine performance, emission characteristics, and abnormal combustion were studied through the engine test performed with the variations of fuel-air equivalence ratio and spark timing. Compared with gasoline, hydrogen burns so fast that cylinder peak pressure and temperature are higher and NO is emitted more at full load condition. IN the case of intake port injection type engine, COVimep becomes lower due to the well-mixing of air and fuel, and engine output is lower owing to the low volumetric efficiency. As fuel-air equivalence ratio goes up, the combustion speed increases, and COVimep decreases. NO emission peaks slightly lean of stoichiometric. As spark timing advances and fuel-air equivalence ratio goes up, the cylinder peak pressure and temperature become higher, so abnormal combustions take place easily.

• Journal of Biomedical Engineering Research
• /
• v.40 no.6
• /
• pp.230-234
• /
• 2019

Medical laser equipment using optical energy is used to surgery and treat diseases by destroying and removing tissue. Domestic laser equipment has been used steadily in the skin and cosmetics sectors and has been changed to radiate high-power energy in a wide range to shorten patient treatment time. However, side effects such as burns and damage of normal tissues occurred. To solve this problem, techniques for detecting lesions using an imaging device and selectively radiating the laser have been developed. In this study, we proposed an evaluation method to evaluate the safety and performance of target detection accuracy, laser irradiation accuracy and motion protection device technology derived from product analysis and investigation. Finally, the validity of the evaluation method was evaluated by evaluating the imaging device based laser equipment as the proposed evaluation method.