• Journal of Oral Medicine and Pain
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• v.20 no.2
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• pp.361-376
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• 1995

The purpose of this study was to investigate the relationship between the head and neck postre and the cervical curvature, especially in forward head postrue(FHP). Sixty patients with craniomandibular disorders and thirty dental students without any signs and symptoms of craniomandibular disordres participated in this study as patient groups and sa control group, respectively. The author evaluated the head and neck posture of all subjects by plumb line and CROM( Cervical Ragne of Motion), and had taken cephaograph in natural head position. On the cephalograph the angle of cervical inclination formed by true horizntal plane and 4th cervical vertebra(C4) and the radius of cervical curvature from C1 to C5 were measured. A specially designed ruler was used for measuring cervical curvature. Occlusal contac number and force with T-scan system, electromygraphic activity of cervical muscles with Bio-EMG, and distance of freeway space with Bio-ECN were recorded, respectively. The collected data were processed by SAS/STAT progrm. The obtained results were as follows : 1. In subjects with longer radius which was less cervical curvature, head positioned more anteriorly than subjects with smaller radius, and they showed slightly straight cervical vertebra. 2. Between the patients and the control group, there were no differences in cervical curvature, in forward head position by plumb line and in CROM. But the patient group had a greater cervical inclination than the control group had. 3. There were positive correlation between cervical curvature and forward head position by plumbline,between forward head position y plumb line and that by CROM in patient group. The cervical inclination, however, had negative correlation with cervical curvature, and with forward head postion by plumb line, respectively. 4. In case of showing more cervical curvature and more forward head position by plumb line the head position was defined as forward head posture. In patient group, subjects without forward head posture showed greater posterior teeth contact force than subjects with forward head posture, but in control group, there were no difference between the two subjects. 5. There were higher electromyographic activity in almost all muscles and smaller freeway space in induced forward head posture than those in natural head position in subjects without forward head posture. In conclusion, head position of patients with craniomandibular disorders were not more anterior than that of normal control person, but they had tendency to head extension. From the result of this study, forward head posture could be defined as posterior rotation of upper cervical segment with a straight lower cercial segment due to loss of normal lordosis.

• Journal of the Semiconductor & Display Technology
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• v.9 no.1
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• pp.67-71
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• 2010

Head up display’s cooling system is auto-diagnosed resulting from the external environment. The quantity of heat depending on this Head up display’s cooling system layout determines the speed of FAN for system cooling. In other words, a system’s heat quantity is planned through the air density depending on altitude, the amount of wind in air depending on FAN control condition, and the algorithm that is proportional to delta temperature. To detect the altitude, we use the criteria of delta T, which is determined by the subtracted value of LED junction temperature, and atmospheric temperature that is recorded on the Head up display system. Depending on the classification of delta T value, the altitude section is determined. While we can use GPS as the tool to detect the altitude, we should predict the change of the air density as the altitude alters, and should not just measure the altitude. And the value of delta T is used as the criterion of detecting the altitude for increasing the cooling efficiency of the car’s inner Head up display system with reflecting the speed of the FAN dependent upon the air density. In our theory, altitude is depending on the value of delta T and stabilizing or maintaining the system’s temperature by changing FAN’s rpm depending on determined value of altitude.

• Journal of dental hygiene science
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• v.24 no.3
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• pp.125-133
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• 2024

Background: The management of dental plaque and the appropriate use of oral hygiene tools are crucial for oral health. With increasing interest in oral health care, various oral hygiene products are available on the market. As the most basic oral hygiene tool, the large-head toothbrush has gained significant consumer interest. This study evaluates the suitability of large-head toothbrushes as oral hygiene tools by comparing their efficacy with that of regular-sized toothbrushes. Methods: We evaluated the efficacy of large-head and regular-sized toothbrushes. The amount of dental plaque before and after brushing was measured using quantitative light-induced fluorescence digital (QLF-D) images and the plaque index (PI) in adult participants with more than 28 teeth (n=15/group). After brushing, the collected toothbrushes were rinsed 10 times in clean water, thoroughly dried, and weighed on an electronic scale. Data were analyzed using the Wilcoxon signed-rank test with SPSS Statistics Version 29.0. Results: QLF-D analysis showed a significant decrease in fluorescence intensity scores after use of a regular-sized toothbrush, whereas the scores after use of a large-head toothbrush were not significantly reduced. PI measurements indicated significant reductions in dental plaque for both head types. However, detailed analysis by tooth surface revealed that the regular-sized toothbrush significantly reduced plaque on the proximal, palatal/lingual, and labial/buccal surfaces. In contrast, the large-head toothbrush only showed significant reductions in place on the proximal and palatal/lingual surfaces, not on the labial/buccal surface. Additionally, compared to the regular-sized toothbrush, the large-head toothbrush retained more toothpaste residue despite similar cleaning efforts after brushing. Conclusion: Compared to the regular-sized toothbrush, the large-head toothbrush showed lower overall efficacy in dental plaque removal. The results of this study provide significant information regarding the use of large-head toothbrushes.

• Journal of Korean Academy of Nursing
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• v.27 no.3
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• pp.503-509
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• 1997

This study was undertaken to identify optimal head elevation and position in the care of the neurosurgical patient with a cerebral aneurysm. The effects of 0°. 15° and 30° head elevation and three positions (supine, side tying position opposite to the operation site, and side tying position on the same side as the operation site) on ICP was studied in fourteen neurosurgical patients with cerebral aneurysms. The results are as follows : 1. The mean intracranial pressure was significantly lower when the patient's head was elevated at 30° as compared to 0° and 15°. 2. The mean intracranial pressure was significantly lower when the patient was positioned in the supine as compared to side tying position opposite to the operation site and side tying position on the same side as the operation site. The data indicate that head elevation to 30° and the supine position reduce ICP in neurosurgical patients with cerebral aneurysm.

• The Journal of Korean Physical Therapy
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• v.31 no.3
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• pp.151-156
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• 2019

Purpose: This study aimed to investigate the immediate effects of posture correction and real-time visual feedback using a video display on muscle activity and change of head position during overhead arm lift test in individuals with forward head posture. Methods: Fifteen subjects with forward head posture and fifteen normal subjects who volunteered were included in this study. During both groups performed the overhead arm lift test, the muscle activity of the upper trapezius, serratus anterior, sternocleidomastoid, and lower trapezius muscle were measured using electromyography, and head position change was measured using photographs. Then, forward head posture group was asked to perform overhead arm lift test again after posture correction and real-time visual feedback using a video display respectively. One-way analysis of variance (ANOVA) was used to analyze four conditions: pre-test, posture correction, real-time visual feedback, and the control group. Results: The upper trapezius and lower trapezius muscle activity significantly decreased posture correction, real-time visual feedback, and control group than pre-test of forward head posture group (p<0.05). The sternocleidomastoid muscle significantly decreased real-time visual feedback and control group than pre-test of forward head posture group. Head position change significantly decreased three conditions than pre-test of forward head posture group and real-time visual feedback and control group significantly decreased than posture correction. Conclusion: This study recommend for maintaining cervical stability during the overhead arm lift test, postural control using real-time visual feedback is more effective in subjects with forward head posture.

• The Journal of Korean Physical Therapy
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• v.25 no.4
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• pp.217-223
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• 2013

Purpose: This study was to investigate whether the two different head postures, natural and ideal head posture, affect head/shoulder posture and muscle activity. Methods: Thirty healthy subjects with the forward head and round shoulder posture were participated in this study. This study utilized a within-subjects design with subjects being positioned into two sitting positions: natural head posture (NHP) and ideal head posture (IHP). Forward head angle (FHA) and forward shoulder angle (FSA) of each subject were measured for assessing the head/shoulder posture and muscle activities of upper trapezius (UT), lower trapezius (LT), and serratus anterior (SA) during the forward overhead reaching. Results: There were significant increases in both FHA and FSA after taking IHP, which showed greater angles than in taking NHP. In change of muscle activities, there were significant decreases in both LT and SA after taking IHP, which showed lower activities than in taking a NHP, whereas there was no significant change in UT. Conclusion: These findings demonstrate that postural alterations associated with forward head and rounded shoulder postures could alter scapular kinetics and muscle activity during the forward overhead reaching.

• Proceedings of the Korea Contents Association Conference
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• 2007.11a
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• pp.865-868
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• 2007

This research is the method that develops the efficient Source Head and the performance of Ion Implanter. Source Head is used during 20 days because Source Head's life time is different from the life time of most components. Components which is replaced to remake the Source Head is very expensive, and moreover, the above of 50% is used with one time. In this research, as we applied the influx method of the atom in aerial distributed method, obtained the effect which suppresses the portion which occurs with loss of thermion and is a possibility of lowering the pressure of the Arc. And then We it will be able to suppress be imbrued of the Chamber.

• Korean Journal of Head & Neck Oncology
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• v.7 no.1
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• pp.10-16
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• 1991

Elective neck dissection (END), provide proper information on nodal status and stage which are significant prognosticator in head and neck cancers with clinically $N_{(0)}$ neck. But there are many controversies for the extents, methods of surgery, moreover, whether normal lymph nodes, local defencer, have to be removed or not. The authors performed 47 END in 39 patients of head and neck squamous cell carcinoma from 1984 to 1989 and a retrospective study of the cases was conducted. Eighteen percent of nodal metastasis and five percent of extracapsular spread were found in END specimens. We concluded that END provide significant information for the management and evaluation of prognosis in head and neck cancer.

• The Journal of Korean Medicine
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• v.17 no.1 s.31
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• pp.433-446
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• 1996

From September 1990 to December 1994, author had treated by acupuncture for 75 cases of strained headache. The results were as follows. 1. There were some kind of head-ache, posterior head-ache( 32.0 % ), lateral head-ache( 28 % ), whole head-ache( 25.3 % ), floating head-ache(8.0%), upper head-ache( 4.0 % ), front head-ache( 2.7 % ). 2. The causes of head-ache were indistinctness ( 34.7 % ), sensibility ( 53.3 % ), indigestion( 12.9 % ), ect. 3. The combined symptoms were indigestion, constipation, sensibility, hypertention, muscle-ache, ect. 4. There were effects of acupuncture treatment, unavailability (25.3 %), availability (74.7 %). 5. There were availability in according with increasing treatment.

• ETRI Journal
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• v.24 no.2
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• pp.176-179
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• 2002

Using scaled models for an anatomical head model and a simple head model, we investigated the effects of head size on specific absorption rate characteristics for two mobile phones operating at 835 MHz and 1765 MHz. Our results showed that a larger head produced a higher localized SAR at 835 MHz. However, at 1765 MHz, the differences among the head models were insignificant since the superficial absorption was dominant over the effects of head shape and size. A larger head produced a lower whole-head averaged SAR at both frequencies.