• Journal of the Korean Institute of Gas
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• v.17 no.2
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• pp.70-77
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• 2013

The present study has been carried out to analyze the effect of steam hammering on the steam piping system including the final superheater, the high pressure turbine, check valve and the first reheater by sudden stoping of main stop valve in a power plant. For the present steam hammering analysis, the well known Flowmaster software has been used to model the steam piping system and the time dependent characteristics of pressure and steam mass flow rate has been conducted. Using the result of the unsteady pressure and steam mass flow rate, the forces acting on the elbows in the piping system has been derived. From the present analysis, it has been elucidated that the elbow just before the main stop valve and the elbow near the connection pipe between bypass pipe and check valve had the largest force among the elbows in the steam piping system. The structural safety diagnostics study on the elbow and the supporting structures of the steam piping system of a power plant will be conducted in the future by the present results of the forces acting on the elbow.

• Tuberculosis and Respiratory Diseases
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• v.82 no.4
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• pp.335-340
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• 2019

Background: Snoring is the cardinal symptom of obstructive sleep apnea (OSA). Snoring and upper airway obstruction associated with major oxygen desaturation may occur in populations undergoing flexible bronchoscopy. Methods: To evaluate the prevalence of patients at a high risk of having OSA among patients undergoing bronchoscopy with sedation and to investigate whether snoring during the procedure predicts patients who are at risk of OSA, we prospectively enrolled 517 consecutive patients who underwent the procedure with moderate sedation. Patients exhibiting audible snoring for any duration during the procedure were considered snorers. The STOP-Bang (Snoring, Tiredness, Observed apnea, high blood Pressure-Body mass index, Age, Neck circumference and Gender) questionnaire was used to identify patients at high (score ${\geq}3$ out of 8) or low risk (score <3) of OSA. Results: Of the 517 patients, 165 (31.9%) snored during bronchoscopy under sedation. The prevalence of a STOP-Bang score ${\geq}3$ was 61.9% (320/517), whereas 200 of the 352 nonsnorers (56.8%) and 120 of the 165 snorers (72.7%) had a STOP-Bang score ${\geq}3$ (p=0.001). In multivariable analysis, snoring during bronchoscopy was significantly associated with a STOP-Bang score ${\geq}3$ after adjustment for the presence of diabetes mellitus, chronic obstructive pulmonary disease, chronic kidney disease, and stroke (adjusted odds ratio, 1.91; 95% confidence interval, 1.26-2.89; p=0.002). Conclusion: Two-thirds of patients undergoing bronchoscopy with moderate sedation were at risk of OSA based on the screening questionnaire. Snoring during bronchoscopy was highly predictive of patients at high risk of OSA.

• International Journal of Highway Engineering
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• v.15 no.6
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• pp.135-141
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• 2013

PURPOSES : The lack of details of design guideline for zig-zag shaped section approaching central bus stop leads an traffic accident proneness. So, this study analysed the geometric elements of central bus stop area in terms of vehicle dynamics and suggested design alternatives. METHODS : The study analysed a dynamic behaviour of bus moving in and out of zig-zag shaped section using Auto-Turn under scenarios. Based upon dynamic analysis, the study found out the width of overtaking lane is the most influential factor for a safe moving at zig-zag alignment. RESULTS : The width of overtaking lane at design speed of 40, 50, and 60 km/h respectively was suggested given taper ratio of 1 to 10 required for Bus Rapid Transit (BRT), and the lane width is not wider than 4.0m which possibly makes two vehicles using the same lane. Also, the width of overtaking lane which mitigates the taper ratio was suggested with the same restriction about the maximum lane width. CONCLUSIONS : The results of the study can be used to prepare a design guideline on zig-zag shaped alignment of central bus exclusive lanes. The more stable moving is expected by applying the design alternatives suggested, therefore the lower rate of traffic crashes at the vicinity of central bus stops.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.10a
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• pp.525-530
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• 2013

With the increasing the importance of emotional quality of vehicle, the sound quality of systems with electric motor components has become increasingly important. Electric motors are used for windows, seats, sun roof, mirrors, steering columns, windshield wiper, climate control blowers, etc. In this paper, a study was conducted to identify sound quality factors that contribute to customer's satisfaction and preference of the window lift system. Jury test for subjective evaluation was carried out and sound quality index was developed. Averaged sound pressure level and sharpness were significant factors when glass moves down. Also, maximum loudness at stop section and averaged loudness were significant factor when glass moves up. Noise source identification was carried out for the reduced the loudness and sharpness during glass transferred section and impulsive noise at stop section, Using the source identification result, several improvement points were applied. And finally, the degree of sound quality improvement was judged using sound quality index.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.92-95
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• 2004

This study proposes an industrial rehabilitation robot system which can exercise two joints in 3 dimensional spaces. The robot kinematics analysis and the results of studies on each joint for the rehabilitation robot could verify possibility of rehabilitation motion to exercise a joint. The force and torques sensor not only measures a rehabilitation performance of subjects between the abnormal limb and the manipulator, but also carries out an important function of safety device to prevent accidents. Also, limit sensors and emergency stop switch are used for high safety in this system. In this real test, the possibility of rehabilitation robot system is evaluated by C&R ARM I which is similar to upper-limb.

• Journal of Fashion Business
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• v.6 no.6
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• pp.12-18
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• 2002

This study was conducted out of necessity for attempting to identify what degree of satisfaction contemporary beauticians having to accomplish this expanded role of theirs had and what factors had an effect on their job satisfaction. Based on the study results, the following conclusion was drawn: 1) It was found that beauticians‘ level of job satisfaction with its components was in the order of 'vocational pride'(3.66), 'human relations'(3.39), 'autonomy'(3.29), 'required job'(3.13), and 'vocational duty'(3.01). 2) It was found that as to the level of job satisfaction according to religions beauticians with Buddhism had the highest level of job satisfaction with each of its components, followed by 'Others'(3.37), 'Christianity'(3.26), 'Catholicity'(3.25) and 'No Religion'(3.24). 3) It was found that as to the level of job satisfaction according to the future plan beauticians saying 'I will stop working at the same time that I marry'(3.68), 'I will continue working'(3.33), 'I will work for several more years'(3.30) and I will stop working at any time depending on circumstances'(3.29).

• Journal of Biomedical Engineering Research
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• v.17 no.2
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• pp.201-208
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• 1996

We have been studying an implant type EMG-controlled electrolarynx. First of all, we propose the sternohyoid muscle(SH) as a control source of the electrolarynx. The purpose of this study is to investigate the possibility that subjects control voluntarily the constriction of their SH, and produce the control signals of electrolarynx. For this pwnan, we carried out four experiments regarding the control of the electrolarynx. At the results, we found that subjects can control the start/stop of constriction and the amplitude of EMG of their SH. Also, we ascertained the possibility that the start/stop of contraction of SH controls OW/OFF of sound source of the electrolarynx and the amplitude of UG of SH controls the pitch frequency of the electrolarynx.

• The Korean Journal of Pharmacology
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• v.2 no.1 s.2
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• pp.13-16
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• 1966

The action of serotonin (5-Hydroxytryptamine) on the excretory function of the kidney was investigated in the dog, utilizing the clearance method and the stop-flow technique. It was shown that serotonin, $10{\mu}g/kg/min$, i. v., exerts a marked antidiuretic effects and elicits a marked hemodynamic changes in the kidney: a highly significant decrease of the glomerular filtration rate and a tendency of decrement in the renal plasma flow. Little change in the systemic blood pressure was noted, and the participation of the antidiuretic hormone in the antidiuretic action was ruled out by adding vasopressin to the infusion fluid. The stop-flow analysis showed that there is no evidence of altered activity in the tubules by serotonin. It was thus concluded that serotonin elicits anti diuresis in the dog by decreasing glomerular filtration rate, which results from the constriction of Vas afferens in the glomeruli.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1601-1602
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• 2007

Steam stop valves of steam turbine in the power plant are at their 100% position and have no movements. Steam control valves, ie governor valves have no movements either at their controlling position on load limit operation. By the way, if there were no change of operation state, steam valves could be sticked mechanically. Because the governor could fail in protecting and controlling steam turbine in case of emergency conditions, the closing test of 100% valve travel must be accomplished periodically for the purpose of testimony of their good conditions. And, As the difference between steam turbine structures exists according to the manufacturer or generation capacity, both steam stop valves and steam control valves differes in structure and operation method. Therefore, it is essential for not only turbine protection but also control for the control engineers to find out composition of steam valves and method of closing test.

• Phonetics and Speech Sciences
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• v.12 no.4
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• pp.57-61
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• 2020

Previous research has indicated that the patterns of phonetic modulations induced by prominence are not consistent across languages but are conditioned by sound systems specific to a given language. Most studies examining the prominence effects in Korean have been restricted to segments in word-initial and phrase-initial positions. The present study, thus, set out to explore the prominence effects for Korean stop consonants in word-medial intervocalic positions. A total of 16 speakers of Seoul Korean (8 males, 8 females) produced word-medial intervocalic lenis and aspirated stops with and without prominence. The prominence was induced by contrast focus on the phonation-type contrast, that is, lenis vs. aspirated stops. Our results showed that F0 of vowels following both lenis and aspirated stops became higher when the target stops received focus than when they did not, whereas voice onset time (VOT) and voicing during stop closure for both lenis and aspirated stops did not differ between the focus and no-focus conditions. The findings add to our understanding of diverse patterns of prominence-induced strengthening on the acoustic realizations of segments.