• 대한치과보철학회지
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• 제40권6호
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• pp.560-571
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• 2002

Jaw relations and the recording methods have been controversial aspects of dentistry. The purpose of this study was to quantify the relative muscle activity of the masseter and temporal muscles in relation to different intermaxillary relations recorded by intra-oral tracer during maximal clenching and to decide the optimal mandibular position. Ten volunteers with healthy TMJ were studied. Intra-oral tracer was assembled and bite block was fabricated in the articulator. Intra-oral tracer was placed in the mouth, and four mandibular positions were recorded. EMG activity was recorded on a BIO-PAK system (Bio-Research Associates, Inc. USA.) in masseter and temporal muscle and compared in each mandibular positions. The results were as follows: 1. In comparison with maximum intercuspation, the chewing position was the most similar followed by tapping position, myocentric position and posterior border position. However the differences were not statistically significant. 2. In comparison of bilateral symmetry of masseter muscle, tapping position was the most symmetrical followed by chewing position and maximum intercuspation. Myocentric position and posterior border position were not symmetrical. (P<.05). 3. In comparison of bilateral symmetry of anterior temporal muscle, chewing position was the most symmetrical followed by posterior border position, maximum intercuspation, myocentric position and tapping position. However the differences were not statistically significant. 4. In comparison of proportionality of anterior temporal muscle to masseter muscle activity on left side, posterior border position was the greatest followed by myocentric position, taping position, chewing position and maximum intercuspation. And the proportionality of posterior border position was greater than that of maximum intercuspation. (P<.05). 5. In comparison of proportionality of anterior temporal muscle to masseter muscle activity on right side, myocentric position was the greatest followed by posterior border position, tapping position, maximum intercuspation and chewing position. However the differences were not statistically significant.

• The Korean Journal of Physiology and Pharmacology
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• 제6권1호
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• pp.9-14
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• 2002

In the present study, we used the microdialysis technique combined with high performance liquid chromatography (HPLC) and electrochemical detection to measure the extracellular levels of norepinephrine (NE) in the posterior hypothalamus in vivo, and to examine the effects of various drugs, affecting central noradrenergic transmission, on the extracellular concentration of NE in the posterior hypothalamus. Microdialysis probes were implanted stereotaxically into the posterior hypothalamus (coordinates: posterior 4.3 mm, lateral 0.5 mm, ventral 8 mm, relative to bregma and the brain surface, respectively) of rats, and dialysate collection began 2 hr after the implantation. The baseline level of monoamines in the dialysates were determined to be: NE $0.17{\pm}0.01,$ 3,4-dihydroxyphenylacetic acid (DOPAC) $0.94{\pm}0.07,$ homovanillic acid (HVA) $0.57{\pm}0.05$ pmol/sample (n=8). When the posterior hypothalamus was perfused with 90 mM potassium, maximum 555% increase of NE output was observed. Concomitantly, this treatment significantly decreased the output of DOPAC and HVA by 35% and 28%, respectively. Local application of imipramine $(50\;{\mu}M)$ enhanced the level of NE in the posterior hypothalamus (maximum 200%) compared to preperfusion control values. But, DOPAC and HVA outputs remained unchanged. Pargyline, an irreversible monoamine oxidase inhibitor, i.p. administered at a dose of 75 mg/kg, increased NE output (maximum 165%), while decreased DOPAC and HVA outputs (maximum 13 and 12%, respectively). These results indicate that NE in dialysate from the rat posterior hypothalamus were neuronal origin, and that manipulations which profoundly affected the levels of extracellular neurotransmitter had also effects on metabolite levels.

• 한국운동역학회지
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• 제26권2호
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• pp.191-195
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• 2016

Purpose: The purpose of this study was to analyze the immediate effects of ankle restriction with an elastic band on ground reaction force during a golf swing. Method: There were five subjects who were teaching pros with an average golf score of 75. A force platform (9281B, Switzerland) was used. The independent variable was the presence of an elastic band. The dependent variables were three-dimensional ground reaction forces to analyze the transfer of momentum with the timing, control and coordination of the three forces. A paired t-test within subject repeated measure design was used via an SPSS 20.0. Results: Wearing an elastic band around one's ankles significantly makes shorter time differences between the moment of cross anterior / posterior forces and vertical force and median value of anterior / posterior forces during the backswing, between medial and lateral maximum and anterior / posterior force from the top of the back swing to the mid down swing, and creates an anterior / posterior maximum force. Conclusion: Wearing an elastic band around one's ankles affects control and coordination between three dimensional forces, and anterior force power according to each phase of the golf swing.

• 대한전자공학회논문지SP
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• 제42권6호
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• pp.43-54
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• 2005

이본 논문에서는 Bayesian 영상 분할법과 SOM(Self Organization feature Map)을 이용한 텍스쳐(Texture) 분할 방법을 제안한다. SOM의 입력으로 다중 스케일에서의 웨이블릿 계수를 사용하고, 훈련된 SOM으로부터 관측 데이터에 대한 우도(尤度, likelihood)와 사후확률을 구하는 방법을 제시한다. 훈련된 SOM들로부터 구한 사후확률과 MAP(Maximum A Posterior) 분류법을 이용하여 텍스쳐 분할을 얻는다. 그리고 문맥 정보를 이용하여 텍스쳐 분할 결과를 개선하였다. 제안 방법은 HMT(Hidden Markov Tree)을 이용한 텍스쳐 분할보다 더 우수한 결과를 보여준다. 또한 SOM과 HMTseg라고 불리는 다중스케일 Bayesian 영상 분할 기법을 이용한 텍스쳐 분할 결과는 HMT와 HMTseg을 이용한 결과보다 더 우수한 성능을 보여준다.

• 한국전문물리치료학회지
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• 제14권4호
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• pp.35-43
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• 2007

The purpose of this study was to compare the static balance in a sitting position between a group with adolescent idiopathic scoliosis (AIS) and a normal aged-matched group. Forty-nine subjects were included in this study. Thirty-one healthy subjects and eighteen AIS subjects were participated. Each group was tested with the Lumbar Trunk Muscle Endurance Test (LTMET) and Balance Performance Monitor (BPM). The parameters for static balance were sway area, sway path, mean balance, maximum velocity, anterior-posterior angle, and left-right angle of each group with eyes opened and closed. Results from the LTMET showed significantly more increase in the normal group than in the AIS group in the flexor and extensor endurance. The BPM tested showed significantly difference beteen the groups in parameters of sitting balance such as maximum velocity and anterior-posterior sway angle. For the AIS subjects, there were no significant differences in all parameters of sitting balance between eyes opened and eyes closed. In comparisons of the groups with eyes opened there were no significant differences in all parameters of sitting balance. In comparisons of the groups with eyes closed there were significant differences in the sway area, maximum velocity, anterior-posterior sway angle and left-right sway angle. These results suggest that the AIS group relies much more on proprioception than on vision, and develops compensatory passive postures of the spine. Further study is needed to measure many AIS patients with morphologic and electromyographic data for clinical application.

• 대한의용생체공학회:의공학회지
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• 제28권1호
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• pp.108-116
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• 2007

Recently, it has been reported that the posterior stabilized implant, which is clinically used for the total knee replacement (TKR), may have failure risk such as wear or fracture by the contact pressure and stress on the tibial post. The purpose of this study is to investigate the influence of the mal alignment of the posterior stabilized implant on the tibial post by estimating the distributions of contact pressure and von-Mises stress on a tibial post and to analyze the failure risk of the tibial post. Finite element models of a knee joint and an implant were developed from 1mm slices of CT images and 3D CAD software, respectively. The contact pressure and the von-Mises stress applying on the implant were analyzed by the finite element analysis in the neutral alignment as well as the 8 malalignment cases (3 and 5 degrees of valgus and varus angulations, and 2 and 4 degrees of anterior and posterior tilts). Loading condition at the 40% of one whole gait cycle such as 2000N of compressive load, 25N of anterior-posterior load, and 6.5Nm of torque was applied to the TKR models. Both the maximum contact pressure and the maximum von-Mises stress were concentrated on the anterior-medial region of the tibial post regardless of the malalignment, and their magnitudes increased as the degree of the malalignment increased. From present result, it is shown that the malalignment of the implant can influence on the failure risk of the tibial post.

• 대한치과교정학회지
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• 제23권4호
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• pp.529-541
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• 1993

The purpose of this study was to investigate not only the variability in the timing and amount of the maximum pubertal spurt in cranial base and mandible, but also its interrelationship with the timing of peak height velocity. This study was carried out by analysing biannual serial lateral cephalometric radiographs of twenty-six males and twenty-one females who were taken from 8.5years to 16.5years old of mean age, according to the established land-marks and linear measurements. The results of this study were summarized as follows. 1. Prevalance of the maximum growth spurt more than 80 percentage was occurred in all measurements of cranial base and mandible, except posterior cranial base length in the female. 2. In all measurements of cranial base and mandible, the maximum spurt was occurred earlier in the female than the male while it was greater in male in all measurements except ramal height. 3. In body height measurement, the peak height velocity was occurred 2 years earlier for the female(11.0 years old) than the male(13.0 years old). 4. The timing of maximum spurt in anterior cranial base length and total mandibular length in both sexes and ramal height in the female were coincided with PHV. The maximum spurt was occurred in both sexes in all measurements 2 years before or after PHV, except mandibular body length and posterior cranial base length the in female. 5. In all ages, there was significant correlation between the total mandibular length and ramal height, and was also correlation between total cranial base length and anterior cranial base length(P<0.05). However, there was no significant correlation between the ramal height and mandibular body length. In addition, there was also no any correlation between the anterior cranial base length and posterior cranial base length in all ages(P>0.05).

• 대한소아치과학회지
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• 제21권2호
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• pp.547-554
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• 1994

Posterior crossbites are abnormal buccal, or lingual relationship of a tooth or teeth of the maxilla, the mandible, or both when the teeth of the two arches are in occlusion and involve the molars and premolars. Posterior crossbites are classified as dental, muscular(functional), or skeletal. In an effort to avoid occlusal interferences caused by the inadequate arch width, the patient deviates the mandible laterally upon closure to achieve maximum intercuspation. This is described as functional posterior crossbite. Correction of functional posterior crossbites in the primary & early mixed dentition as early as possible after diagnosis has been recommended, because crossbites do not automatically improve with the eruption of the permanent teeth. Functional posterior crossbites, if left untreated, may have deleterious effects on the development and function of the TMJ. The diagnosis and management of three cases is presented. Each patient with functional posterior crossbites is treated using the bilateral maxillary expansion appliance.

• Journal of Oral Medicine and Pain
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• 제40권3호
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• pp.115-123
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• 2015

Purpose: The aim of this study was to elucidate the coordination patterns of the sternocleidomastoid and posterior cervical muscles in response to symmetrical and asymmetrical jaw functions in normal adults. Methods: Twenty-seven healthy volunteers (8 females, 19 males; mean age, $30.4{\pm}2.5$ years) participated in this study. Surface electromyography (EMG) was used to record activities in the masseter, suprahyoid, sternocleidomastoid, and posterior cervical muscles at rest and during maximum tooth clenching, biting of a cotton roll with the anterior teeth, unilateral biting of a cotton roll with the posterior teeth, bilateral biting of cotton rolls with the posterior teeth, and jaw opening while seated. Normalized amplitude, activity indices, and asymmetry indices were compared between the muscles and the jaw tasks. Results: During symmetrical jaw functions (e.g., tooth clenching, biting with the anterior teeth, bilateral biting with the posterior teeth, jaw opening), the sternocleidomastoid and posterior cervical muscles showed elevated EMG amplitudes compared with the resting condition. The co-activation pattern of the sternocleidomastoid muscle was more pronounced than those of the posterior cervical muscles during these tasks. During asymmetrical jaw functions (e.g., unilateral biting with the posterior teeth), the ipsilateral sternocleidomastoid and masseter muscles showed higher contraction activity than did the contralateral muscles, but the contralateral posterior cervical muscles were more active than the ipsilateral muscles. Conclusions: The sternocleidomastoid and posterior cervical muscles were shown to be co-activated and coordinated anteroposteriorly or bilaterally according to symmetrical or asymmetrical jaw function. These results suggest an integrated neural control mechanism for the jaw and neck muscles, and provide further evidence supporting the intimate functional coupling between the trigeminal and cervical neuromuscular systems.

• 한국음향학회지
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• 제21권2호
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• pp.190-198
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• 2002

화자확인에서 사용되는 디코딩 방법에는 음성인식에서 주로 사용되는 비터비 알고리듬을 사용하여 왔다. 그러나 화자확인에서는 화자의 특성을 최대한 발휘하여 같은 음소라도 화자마다 다르게 인식해야 하는 어려움이 있다. 본 논문에서는 기존 화자확인 디코딩에서 사용하는 비터비 알고리듬을 대신하는 새로운 알고리듬을 제안하였다. 제안된 알고리듬은 음성인식에서 사용되고 있는화자 적응 알고리듬을 화자의 특성에 따라 모델 파라미터로 변환하는 것을 응용한 방법이다. 본 논문에서는 여러 적응 알고리듬중 MLLR(Maximum Likelihood Linear Regression)과 MAP (Maximum A-Posterior) 적응 알고리듬을 사용하였고 제안된 알고리듬이 기존의 비터비 알고리듬을 사용하였을 때보다 평균 30%의 EER (Equal Error Rate) 향상을 이루었다.