• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.6
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• pp.68-77
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• 2013

This study suggested experimental study results of congestion detection method for intruding vehicle enforcement system. This congestion detection method is developed to determine optimal operation criteria of intruding vehicle enforcement system as detecting traffic congestion. In ITS sector, traffic management systems generally have used a sectional travel speed for congestion detection. However, image sensors have high error rate of congestion detection because of speed error. This study suggested comprehensive congestion detection criteria based on speed and occupancy rate using field studies. As field study results, the proposed intruding vehicle enforcement system using image sensor is capable of accurately detecting the traffic congestion using sectional speed of 20km/h and occupancy rate of 60% as congestion detection criteria.

• The Korean Journal of Pain
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• v.30 no.1
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• pp.51-58
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• 2017

Background: Recently symptoms-based screening questionnaires have gained attention for screening for a neuropathic pain component (NePC) in various chronic pain conditions. The present study assessed the usefulness of four commonly used NePC screening questionnaires including the Self-completed douleur neuropathique 4 (S-DN4), the ID Pain, the painDETECT questionnaire (PDQ), and the Self-completed Leeds Assessment of neuropathic Symptoms and Signs (S-LANSS) questionnaire in patients with chronic low back pain (CLBP) to assess the presence of NePC. Methods: This is a single-center cross-sectional study where patients with CLBP, with or without leg pain, were included. Participants were initially screened for NePC presence by a physician according to the regular practice, and later assessed using screening questionnaires. The diagnostic accuracy of these questionnaires was compared assuming the physician-made diagnosis as the gold standard. Results: A total of 215 patients with CLBP of which 164 (76.3%, 95% CI, 70.2-81.5) had a NePC were included. S-DN4, ID Pain, and PDQ have an area under the curve (AUC) > 0.8 indicating excellent discrimination. However, S-LANSS has an AUC of 0.69 (0.62-0.75), indicating low discrimination. S-DN4 has a significantly higher AUC as compared to ID Pain (d(AUC) = 0.063, P < 0.01) and S-LANSS (d(AUC) = 0.197, P < 0.01). But the AUC of S-DN4 does not significantly differ from that of PDQ (d(AUC) = 0.013, P = 0.62). Conclusions: S-DN4, ID Pain, and PDQ, but not S-LANSS, have good discriminant validity to screen for NePCs in patients with CLBP. Despite using all the tests, 20-30% of patients with an NePC were missed. Thus, these questionnaires can only be used as an initial clue in screening for NePCs, but do not replace clinical judgment.

• Aerospace Engineering and Technology
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• v.8 no.1
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• pp.32-41
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• 2009

In this study, scale-down design of full-scale Korean Utility Helicopter (KUH) main rotor blade has been investigated. The scaled model system were designed for the measurement of aerodynamic performance, tip vortex and noise source. For the purpose of considering the same aerodynamic loads, the Mach-scale method has been applied. The Mach-scaled model has the same tip Mach number, and it also has the same normalized frequencies. That is, the Mach-scaled model is analogous to full-scale model in the view point of aerodynamics and structural dynamics. Aerodynamic scale-down process could be completed just by adjusting scaling dimensions and increasing rotating speed. In the field of structural dynamics, design process could be finished by confirming the rotating frequencies of the designed blade with the stiffness and inertial properties distributions produced by sectional design. In this study, small-scaled blade sectional design were performed by applying domestic composite prepregs and structural dynamic characteristics of designed model has been investigated.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.5999-6004
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• 2012

Measurement of quality of life among prostate cancer patients helps the health care providers to understand the impact of the disease in the patients' own perspective. The main aim of this study is to measure the quality of life among prostate cancer patients at University Malaya Medical Center (UMMC) and Universiti Kebangsaan Malaysia Medical Centre (UKMMC) and to ascertain the association factors for physical coefficient summary (PCS) and mental coefficient summary (MCS). A hospital based, cross sectional study using the Short Form-36 (SF-36) questionnaire was conducted over a period of 6 months. A total of 193 respondents were recruited. Their total quality of life score was $70.1{\pm}14.7$ and the PCS score was lower compared to MCS. The factors associated for PCS were: age, living partner, renal problem, urinary problem of intermittency, dysuria and hematuria. Factors associated for MCS were: age, living partner, renal problem, presenting prostatic specific antigen and urinary problem of intermittency and dysuria. Our prostate cancer patients had moderate quality of life in the physical health components but their mental health was less affected.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4743-4750
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• 2013

Background: Identifying and managing osteoporosis among cancer survivors is an important issue, yet little is known about the bone health of cancer survivors in Korea. This study was designed to measure the prevalence of osteoporosis and to assess related factors among Korean cancer survivors. Materials and Methods: This study was designed as a cross-sectional analysis. Data were obtained from dual energy X-ray absorptiometry measurement of the lumbar vertebrae and femoral neck, and from standardized questionnaires among 556 cancer survivors and 17,623 non-cancer controls who participated in the Fourth and Fifth Korea National Health and Nutrition Examination Surveys (2008-2011). We calculated adjusted proportions of osteoporosis in non-cancer controls vs. cancer survivors, and we performed multivariate logistic regression analysis. Results: The prevalence of osteoporosis among cancer survivors was significant higher than that of the non-cancer controls after adjusting for related factors. Furthermore, osteoporosis among cancer survivors was higher in elderly subjects (60-69 years : adjusted odds ratio (aOR) 3.04, 95% CI : 1.16-8.00, ${\geq}70$ years : aOR 6.60, 95% CI 2.20-19.79), in female cancer survivors (aOR: 7.03, 95% CI: 1.88-26.28), and in a group with lower monthly income (aOR: 3.38, 95% CI: 1.31-8.71). In male cancer survivors, underweight and lower calcium intake were risk factors. Conclusions: These data suggest that the osteoporosis among cancer survivors varies according to non-oncologic and oncologic factors. Effective screening should be applied, and a sufficient and comprehensive management should be matched to individual cancer survivors early after cancer treatment.

• Journal of Korean Society of Steel Construction
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• v.10 no.2 s.35
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• pp.153-160
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• 1998

The sectional dimensions and initial crookedness of the RHS(rectangular hollow section, ${\boxe}-75{\times}75{\times}3.2,\;{\boxe}-100{\times}100{\times}4.2,\;{\boxe}-125{\times}125{\times}6.0$) were measured. The axial compressive strength tests for columns with slenderness $46{\sim}84$ were performed as well as stub tests and tensile tests. FEM analysis was also used. The measurement shows that the errors of sectional dimensions are negligible. For the column length corresponding to ${\lambda}=100$, the initial crookedness with the 2.5% probability estimated from the measured results is 1/490, 1/1121 1/1395 for each section respectively. The yield strengths obtained from tensile test are higher than the specified minimum value by more than 30%. The column test shows that the maximum axial resistances are almost same as, or a little higher than the FEM results and the specified strength curves of AISC Specification and Eurocode, when the maximum strengths from the stub tests are used as the yield strength of the steel. But the test results show much higher column strength than those specified in the Standard and Code, when the specified minimum yield strength of the steel is used.

• Korean Journal of Optics and Photonics
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• v.29 no.3
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• pp.99-103
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• 2018

Optical coherence elastography (OCE) is based on optical coherence tomography (OCT), which is a noninvasive, high-resolution, cross-sectional imaging technique. In this paper, we have developed dynamic optical coherence elastography to measure elasticity, a mechanical property of tissue, by phase difference. A piezoelectric actuator was used for sinusoidal mechanical loading of samples. Before applying this method to biomaterial, we assessed the feasibility of OCE with samples of sponge, eraser, and sharp lead. Cross-sectional and phase-difference images of the sample were obtained under sinusoidal loading. The strain rate was calculated from the phase-difference information. To obtain the envelope of the phase-difference oscillations along the horizontal direction, Hilbert transformation was performed at each depth. The elevation of the envelope was represented by color mapping, and we could measure the relative elasticity within the sample by comparing the elevations. Finally, there was an advantage when we calculated the shear rate using self-interference in the sample arm, instead of the interference between sample and reference arms.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.43 no.2
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• pp.100-105
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• 2017

Objectives: Localization of the mandibular canal (MC) and measurement of the height and width of the available alveolar bone at the proposed implant site in the posterior segment of the mandible using cone-beam computed tomography (CBCT) in patients with a single missing tooth. Materials and Methods: A cross-sectional study was performed where CBCT scans of the patients with a single missing tooth in the posterior segment of the mandible-premolar, I (1st) molar, and II (2nd) molar were used. The scans were assessed using OnDemand3D software (version 1.0; CyberMed Inc., Seoul, Korea) for localization of the MC asnd remaining alveolar bone both vertically (from the superior position of the MC to the crest of the alveolar ridge) and horizontally (buccolingual, 3 mm below the crest of the alveolar ridge). The findings were statistically analyzed using independent t-test. Results: A total of 120 mandibular sites (40 sites for each of the three missing premolar, I molar, and II molar) from 91 CBCT scans were analyzed. The average heights (from the alveolar crest to the superior margin of the MC) at the premolar, I molar, and II molar areas were $15.19{\pm}2.12mm$, $14.53{\pm}2.34mm$, and $14.21{\pm}2.23mm$, respectively. The average widths, measured 3 mm below the crest of the alveolar ridge, at the premolar, I molar, and II molar areas were $6.22{\pm}1.96mm$, $6.51{\pm}1.75mm$, and $7.60{\pm}2.08mm$, respectively. There was no statistically significant difference between males and females regarding the vertical and horizontal measurements of the alveolar ridges. Conclusion: In the study, the measurements were averaged separately for each of the single missing teeth (premolar, I molar, or II molar), giving more accurate information for dental implant placement.

• Physical Therapy Rehabilitation Science
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• v.9 no.4
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• pp.275-280
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• 2020

Objective: Compression wear is an external aid which promotes performance and recovery, diminishes muscular microtrauma, reduces muscle fiber recruitment, improves neuromechanics, enhances coordinative activities, and reduces the perceived exertion. The purpose of this study was to investigate the relationship between athletic taping and compression wear on dynamic postural balance in healthy young men. The hypothesis was that the athletic taping and compression wear would affect dynamic postural balance, with athletic taping having a different effect on dynamic postural balance in healthy young adults. Design: Cross-sectional study. Methods: Thirty-seven healthy young men participated in this study. To examine the association between athletic taping and compression wear, 3 clinical measurement tools, including 5 times sit-to-stand (5xSTS), one-leg standing (OLS) test, and Y-balance test (YBT) in 5 different conditions, namely (1) non-supporting, and support with (2) athletic taping, (3) regular compression wear, (4) silicon compression wear, and (5) double-fiber compression wear were used. Results: The distance of the Y-balance test (YBT) on both the dominant and non-dominant sides showed a statistically difference among the 5 supporting conditions (p<0.05). The distance measured via the YBT in the non-support condition was significantly different than that in the other four supporting conditions (p<0.05). However, 5xSTS and OLS were not significantly different in these supporting conditions. Conclusions: The results of this study suggest that athletic taping, silicon compression wear, and double-fiber compression wear were more effective for dynamic balance than non-supporting and regular compression wear.

• Safety and Health at Work
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• v.10 no.3
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• pp.254-259
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• 2019

Background: This cross-sectional study assessed the sleep quality using the ActiGraph and investigated the relationship between the parameters of sleep assessment and the type of shift work in Korean firefighters. Methods: The participants were 359 firefighters: 65 day workers (control group) and 294 shift workers (shift work group: 77 firefighters with 3-day shift, 72 firefighters with 6-day shift, 65 firefighters with 9-day shift, and 80 firefighters with 21-day shift). Sleep assessments were performed using the ActiGraph (wGT3X-BT) for 24 hours during day shift (control and shift work group) and night shift and rest day (shift work group). The participants recorded bed time and sleep hours during the measurement period. Results: Sleep efficiency, total sleep time, and percentage of wake after sleep onset during night work were lower in the shift work group than control group (p < 0.05). Sleep efficiency decreased in night shift and increased in rest day, whereas wake after sleep onset increased in night shift and decreased in rest day (p < 0.05). Among shift work groups, sleep efficiency of 6-day shift was higher in day shift, and sleep efficiency of 21-day shift was lower in night shift than other shift groups (p < 0.05). Conclusion: We found that the sleep quality in night shift of the shift work group was poorer than the control group. As to the type of shift work, sleep quality was good in 6-day shift and poor in 21-day shift. Thus, fast rotating shift such as 6-day shift may be recommended to improve the sleep quality of the firefighters.