• Journal of International Academy of Physical Therapy Research
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• v.4 no.2
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• pp.633-639
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• 2013

This study aims to reveal the impact of continuous antagonist strengthening(CAS) and Evjenth-Hamberg stretching(EHS) on the cervical mobility in the university students with abnormal transformation of forward head posture(FHP). Our experiment was conducted 3 times a week for 6 weeks in a total of 20 individuals : continuous antagonist strengthening(CAS) group(n=10) & Evjenth-Hamberg stretching(EHS) group(n=10). In a pre and post comparison, both CAS group and EHS group appeared significantly in mSBI and SBA(p<.05) and the two-group comparison showed a significant difference(p<.05) : CAS group showed better effects. Thus, it is considered that the combined use with continuous antagonist strengthening(CAS) had better effects for cervical mobility than Evjenth-Hamberg stretching(EHS) alone.

• 유체기계공업학회:학술대회논문집
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• 2001.11a
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• pp.191-196
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• 2001

In the systems with largely pipe head loss, variable speed pumps are generally used because substantial energy saving can be expected from such systems by controlling pump speed and also they offer simpler maintenance and operational ease even in conditions where abrupt changes In flow rate and head can occur. The invertor or the fluid coupling system are mainly adopted to control the rotating speed. In this paper, operating conditions at Migum pressing pump station(5 stage), where the fluid coupling system was the first installed for KOWACO, are investigated and analysed so that information thus gained can be usefully employed in the efficient operation of variable speed pump in new installations of in-line booster pumping station.

• The KSFM Journal of Fluid Machinery
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• v.10 no.4
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• pp.21-28
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• 2007

The ratio of disk friction loss in a centrifugal pump is very large for the total pump loss in the range of very low specific speed. Therefore, impeller radius should be shortened to increase the pump efficiency because the disk friction loss is proportional to the fifth power of impeller radius. In order to compensate the decreased head by the shortened impeller radius, vane angle at impeller outlet should be increased. However, as the vane angle at impeller outlet becomes larger, performance instability occurs at low flow rate regions. In this study, J-Groove is adopted to suppress the performance instability and detailed examination is performed for the influence of the J-Groove on the pump performance. The results show that J-Groove gives good effect on the suppression of performance instability. Moreover, as J-Groove increases pump head considerably, the pump size can be smaller for head requirements.

• 한국전산유체공학회:학술대회논문집
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• 2004.10a
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• pp.33-36
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• 2004

The ballast tank of a ship is a system that realizes the required shipping condition and controls the draft of a ship. The loading/unloading of the ballast tank is frequently operated during navigation and the accurate prediction of the loading/unloading time is very important. A numerical algorithm that predicts the loading/unloading time of the ballast tank has been developed and applied to the prediction of the loading/unloading time of the ballast tank with various piping systems. This algorithm can be useful in optimizing the ballast tank system in early design stage.

• Journal of the Optical Society of Korea
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• v.17 no.3
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• pp.242-248
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• 2013

Full color holographic optical element fabrication using a photopolymer is proposed for a waveguide-type head mounted display. The fabricated full color holographic optical elements can be attached to the waveguide to replace the conventional couple-in and couple-out optics in the head mounted display. To implement the system, this study analyzed the optical characteristics of the photopolymer using three lasers (red, green and blue). Considering the color uniformity, a new laminated structure for a full color holographic optical element was also designed. The proposed system was confirmed experimentally.

• Parasites, Hosts and Diseases
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• v.22 no.2
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• pp.273-276
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• 1984

The purpose of this study is to know the present situation of head louse infestation among the students in Ysngyang-gun, Kyongsangbuk-to. From May 11 to June 20, 1984, a total of 5,937 students in 23 primary and 3 middle schools were examined to identify the adult worms of head louse andlor their nits on the hair. The results are as follows: 1, The overall infestation rate was 44.5% and the rates ranged from 19.6% to 88.6%A by each school. 2. In primary schools, the rate was 53.0%A and in middle schools, 27. 1%. 3. The school boys'rate was 33.2% and the school girls'55.6%, and the difference was statistically significant (P<0.001) . 4. The rates were different by grades in middle schools. 5. The rates were different by areas (Myons) (p<0.001) . 6. The adult worms collected from the students were Pediculus humanus roar. capitis.

• Proceedings of the KSLP Conference
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• 1999.11a
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• pp.186-186
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• 1999

Tracheoesophageal fistulation following total laryngectomy has widely been used for voice restoration, This technique make exhaled air to divert to hypopharynx where phayngoesophageal segment forms the neoglottis. Even through layngectomized patients loss the normal laryngeal adjustment for speaking, it has been known that voiced and voiceless sounds are prodused in TE phonation. Nine TE speakeres were subjected to present study designed to clarity the mechanism of neoglottic adjustment in TE phonation, Fiberoptic examination and radiologic studies were performed at all patients and EMG study was performed at 3 patients during I phonation. Fiberoptic ＆ radiologic studies revealed the location of neoglottis, so called pharyngoesophargeal segment which was vibrated well. EMG activity increased for sound production at retropharyngeal prominence. These results indicated that neoglottic adjustment in TE phonation.

• Korean Journal of Head & Neck Oncology
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• v.7 no.1
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• pp.3-9
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• 1991

Brachytherapy is a method of radiotherapy in advantage to achieve better local control with minimum radiation toxicity in comparison with external irradiation because radiation dose is distributed according to the inverse square low of gamma-ray emitted from the implanted sources. The main characteristics of brachytherapy are delivering of higher dose to target volume shortening of total treatment period and sparing of normal tissue. Recent development of iridium ribbons for low dose rate implant provides improvement of technology of brachytherapy in terms of safety and efficiency. High dose rate method. on the other hand, is effective to avoid unnecessary expoure of medical personnel.

• Journal of the Ergonomics Society of Korea
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• v.15 no.1
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• pp.69-78
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• 1996

Current fighter pilots, flying new generation aircrafts with high performance, are under severe stress during aerial combat maneuvering when they are exposed to high sustained +Gz(Head-to-foot) acceleration stress. Two major factor limiting performance during high sustaied +Gz acceleration stress are loss of vision-greyout or blackout, and loss of consciousness (LOC). These symptoms are believed to occur as a result of insuff- icient blood flow to the retina and the brain. This study was conducted to evaluate the effects of high sustained +Gz stress under different seat back angle. The results. obtained by the biodvanmic computer simulations using the ATB(articulated total body) model, are represented with respect to three variables, such as HIC(head injury criterion) value, average G, and maximum G. The results demonstrate that the seat back angle(over $30^{\circ}C$) had a significant effect to decrease +Gz stress on the head segment and had no significant effect on HIC.

• Parasites, Hosts and Diseases
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• v.33 no.3
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• pp.243-244
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• 1995

The survey of the head louse infestation of primary school children in Inchon city was carried out in May 26-27, 1995. Total number of the children surveyed were 1, 530. Four (0.5%) out of 768 boys were infested with nits or adults/nymphs of lice and 72 (9.4%) out of 762 girls were positive with those of lice. The infestation rate of lice for girls was 19 times higher than that of boys.