• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.617-623
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• 2020

Urban railroad vehicles carry many passengers and are the core of an urban railroad transportation system. Therefore, the dynamic performance of the vehicle must be ensured. Dynamic behaviors such as the vibration and ride comfort of railway vehicles are affected by the structure of the suspension system. We analyzed the dynamic behavior of a railway vehicle according to the suspension system of an urban railway vehicle, which is mainly operated in Korea. For two types of vehicles with different suspension structures, the vibration of the vehicles on railway tracks was measured, and dynamic behavior characteristics such as vibration, ride, and vibration reduction rate were analyzed. The result of the test shows that the vibration performance of the body is superior to that of B-bogie in the lateral direction and that of A-bogie in the vertical direction. Overall, the ride quality of the A-bogie car is superior to that of B-bogie. When analyzing the vibration attenuation rate of primary suspension system, the vibration attenuation performance of B-bogie with coil spring was superior to that of A-bogie with a conical rubber spring. The secondary suspension system has better vibration attenuation performance for A-bogie with air springs compared to coil springs.

• Clinics in Shoulder and Elbow
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• v.19 no.3
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• pp.125-129
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• 2016

Background: Superior migration of humeral head has been conventionally determined by measuring the acromiohumeral distance (AHD), We sought to devise a novel measurement system more reliably and accurately than AHD. We described a structural landmark called 'C-line'. In this study, we investigated the clinical usefulness of 'step-off of the C-line (SOC)' compared to that of AHD. Methods: The C-line formed from the medial margin of the proximal humeral head continuing up to the inferior margin of the articular glenoid and then to the lateral border of the scapula. The superior migration of the humeral head triggered by a rotator cuff tear introduces a discontinuity in this C-line. We measured the distance of this discontinuity. We enrolled 144 patients who underwent a rotator cuff repair. We selected 58 controls who didn't have any cuff lesions apparent on magnetic resonance imaging. Using radiographs derived from standardized true anteroposterior views of the shoulder, we measured the SOC and the AHD. We used t-tests for statistical analyses. Results: A rotator cuff tear was associated with an increase in SOC and a decrease in AHD. In control group, the mean SOC was $1.29{\pm}1.71mm$ and AHD was $9.71{\pm}2.65mm$. In cuff tear group, the mean SOC was $3.15{\pm}3.41mm$ and AHD was $8.28{\pm}1.76mm$. The mean SOCs of the patient group in relation to the mean SOC of the control group according to tear size, the SOCs of medium tear and lager groups showed statistically significant increase (p<0.05). Conclusions: The SOC may be a similarly effective to diagnose cuff tears of medium size and larger compared with AHD.

• Tuberculosis and Respiratory Diseases
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• v.53 no.3
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• pp.337-343
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• 2002

A tracheal bronchus, an aberrant bronchus arising directly from the trachea, is an infrequent congenital anomaly. The incidence of this anomaly ranges from 0.5 to 5%. It usually originates from the right lateral wall of the trachea at the level <2 cm above the tracheal bifurcation. These patients usually are asymptomatic, but some patients may experience recurrent pneumonia, chronic bronchitis, bronchiectasis, or asthmatic episodes. A tracheal bronchus may be associated with other anomalies such as a tracheal stenosis, pulmonary agenesis, pulmonary sequestration, congenital heart disease, a pulmonary venous anomaly and Down's syndrome. This anomaly is usually diagnosed incidentally during bronchoscopy in patients with respiratory problems. Here we report a case of a 20-year-old man with a past history of bronchial asthma, which was incidentally diagnosed as a tracheal bronchus during a medical examination prior to military service, and was associated with a bilateral superior vena cava anomaly.

• The Journal of Korean Academy of Prosthodontics
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• v.8 no.1
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• pp.85-89
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• 1968

The author has carried out the statistical standards on liner and angular measurements of sells turcica in 244 normal Korean of various age group by means of lateral cephalometric radiography. The results were as follows; 1. The linear measurements between Ant-Post distance and distance from the tip of tuberculum of sellae to posterior clinoid process were obtained 14.81mm, 9.85mm in the age of 5 years old male and 14.44mm, 9.52mm in female, respectively. There was no outstanding difference with age, but more predominant in female than male. 2. The linear measurements of inferior depth show somewhat increases but no changes in superior depth. 3. It has been showed that the greatest width revealed significant increment beyond 15 years old of both sexes in Korean. 4. None of the significant difference in angular measurement was found with age, but angulation for dorsum sellae decreased after 15 years of male. 5. Generally speaking, increment rates of female in each items were greater than male.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.6
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• pp.558-562
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• 2010

Sinusitis has been reported as a complication of sinus lift surgery. Obstruction of the sinus outflow tract by mucosal edema and particulate graft material may result in sinusitis. Two main surgical procedures have been proposed for the treatment of associated infectious complications; inferior meatal antrostomy and functional endoscopic sinus surgery through transnasal approach. We performed superior lateral wall antrostomy through introral approach in patient suffering from the sinusitis after sinus floor augmentation and implant installation. This procedure permitted easier access to the maxillary sinus for treat sinusitis caused by sinus lifting.

• Journal of Oral Medicine and Pain
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• v.23 no.1
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• pp.75-84
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• 1998

The Purpose of this Study was to examine the anatomic differences in the upper airway according to severity of respiratory disturbance index of habitual snorers. Forty-three male habitual snorers, aged 28-68, were examined by polysomnography and divided into 4 groups according to severity determined by polysomnography. Anatomic differences in the upper airway were assessed by lateral cephalograms in upright position, and epidemiological surveys were done by using questionnaires. The obtained results were as follows : 1. All subjects were habitual snorers and 35 patients (81.4%) complained the loudness of snoring as severe as be heard outside of the room. 2. According to the results of polysomnography, the number of the primary snoring patients was 7(16.3%), mild obtrusive sleep apnea 7(16.3%), moderate 7(16.3%), and severe 22(51.2%). 3. The respiratory disturbance index (RDI) of subjects was 39.5$\pm$24.4 and the body mass index(BMI) was 26.2$\pm$2. 4. More inferiorly positioned hyoid bone according to the degree of respiratory disturbace index (RDI) was observed. (p<0.001) 5. The width of superior oropharyngeal airway space was according to the degree of RDI. (p<0.001)

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.17 no.1
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• pp.223-232
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• 1987

The author obtained the transcranial-oblique lateral radiograms from 78 patients(26 male, 52 female) with temporomandibular dysfunction problem. And then, the author analyzed the dimensional changes of the TMJ space on centric occlusion, horizontal condylar movement and antero-posterior positional relationship of condyle to the articular eminence on 2.54㎝ mouth opening with clicking, TMJ pain and mouth opening limitation repectively, which were the symptoms of the temporomandibular joint pain dysfunction problem, and compared these data with control group. The results were as follows: 1. In centric occlusion, anterior and posterior TMJ space of experimental group was slightly lesser than those of the control group, also superior TMJ space of experimental group was significantly lesser than that of the control group. (p<0.01) 2. In 2.54㎝ mouth opening, the condylar horizontal movement and the antero-posterior positional relationship to the articular eminence were significantly lesser than those of the control group. (p<0.01) 3. Examined experimental group, the degree of condylar horizontal movement of affected ide was lesser than that of the normal side in 2.54㎝ mouth opening.

• The Korean Journal of Physiology
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• v.28 no.2
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• pp.113-122
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• 1994

The present study was carried out to characterize the functional properties of spinomesencephalic tract (SMT) neurons in the lumbar spinal cord of urethane anesthetized rats. Extracellular single unit recordings were made from neurons antidromically activated by stimulation of the midbrain area, including the deep layers of superior colliculus, periaqueductal gray and midbrain reticular formation. Recording sites were located in laminae I-VII of spinal cord segments of L2-L5. Receptive field properties and responses to calibrated mechanical stimulation were studied in 78 SMT cells. Mean conduction velocity of SMT neurons was $19.1{\pm}1.04\;m/sec$. SMT units were classified according to their response profiles into four groups: wide dynamic range (58%), deep/tap (23%), high threshold (9%) and low threshold (3%). A simple excitatory receptive field was found for most SMT neurons recorded in superficial dorsal horn (SDH). Large complex inhibitory and/or excitatory receptive fields were found for cells in lateral reticulated area which usually showed long after-discharge. Most of SMT cells received inputs from $A{\delta}$ and C afferent fiber types. These results suggest that sensory neurons in the rat SMT may have different functional roles according to their location in the spinal cord in integrating and processing sensory inputs including noxious mechanical stimuli.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.5
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• pp.482-487
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• 2006

As the uses of dental implants are prevailing, the need for sinus bone graft is increasing. Deproteinized bovine bone mineral (DBBM) was not mentioned in 1996 Sinus Bone Graft because of the deficit of the available data. Since then, many clinical and laboratory reports support the use of DBBM in the sinus bone graft procedure. In this report, the histological and clinical successes of sinus bone grafting with DBBM is discussed with available literatures. After sinus bone grafts with DBBM, the proportion of new bone formed was similar or superior to natural maxillary posterior alveolar bone after healing period of 6 months to 1 year. It seems that the grafted DBBM is not be either resorbed nor replaced with bone, but this may not disturb the osseointegration of dental implants installed into it. The clinical survival rates of dental implants installed on the sinus grafted with DBBM was similar to those installed on the ungrafted posterior maxillary alveolar ridge or grafted with autogenous bone. So, it can be concluded that DBBM can be used successfully in the sinus bone graft.

• Korean Journal of Medicinal Crop Science
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• v.10 no.3
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• pp.181-184
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• 2002

This study was conducted to select the optimum cultivar of wasabi in water condition. In three cultivar, Daruma, Simanesarai and Daihoichigo, the Daruma was superior to the others. Though total rhizome weight was similar to Daruma and Daihoichigo, rhizome of main stem of Daruma was bigger than that of Daihoichigo, specially distribute in $80{\sim}159g$ size. The allylisothiocyanate content was higher in rhizome than that of leaf, lateral rhizome and petiole. In three cultivar, the allylisothiocyanate content of rhizome, Daihoichigo, Daruma and Simanesairai was 0.3389, 0.6332, 0.3956(mg/g), respectively.