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1.
Sensors (Basel) ; 22(17)2022 Sep 05.
Article in English | MEDLINE | ID: mdl-36081175

ABSTRACT

Active research on crack detection technology for structures based on unmanned aerial vehicles (UAVs) has attracted considerable attention. Most of the existing research on localization of cracks using UAVs mounted the Global Positioning System (GPS)/Inertial Measurement Unit (IMU) on the UAVs to obtain location information. When such absolute position information is used, several studies confirmed that positioning errors of the UAVs were reflected and were in the order of a few meters. To address these limitations, in this study, without using the absolute position information, localization of cracks was defined using relative position between objects in UAV-captured images to significantly reduce the error level. Through aerial photography, a total of 97 images were acquired. Using the point cloud technique, image stitching, and homography matrix algorithm, 5 cracks and 3 reference objects were defined. Importantly, the comparative analysis of estimated relative position values and ground truth values through field measurement revealed that errors in the range 24-84 mm and 8-48 mm were obtained on the x- and y-directions, respectively. Also, RMSE errors of 37.95-91.24 mm were confirmed. In the future, the proposed methodology can be utilized for supplementing and improving the conventional methods for visual inspection of infrastructures and facilities.

2.
Article in Korean | WPRIM (Western Pacific) | ID: wpr-916418

ABSTRACT

Purpose@#The purpose of this study was to analyze retinal capillary parameters using optical coherence tomography angiography (OCTA) of the affected eye and the fellow eye of unilateral normal tension glaucoma (NTG) patients and compare the findings with eyes from a normal control group. @*Methods@#A retrospective cross-sectional study was carried out on patients diagnosed with unilateral NTG (24 affected eyes and 24 fellow eyes each) and normal individuals (29 eyes, the control group). OCTA was used to measure the vascular density (VD) and perfusion density (PD) of the macular area and the peripapillary area. @*Results@#In the superficial capillary plexus, the fellow eye group of unilateral NTG patients showed a decrease in VD of the inner-inferior and PD of the inner-inferior and outer-average peripapillary area, compared with the normal control group (p = 0.008, p < 0.001, and p = 0.001). In the affected NTG eye group, the VD (p = 0.014, p = 0.011, p < 0.001, p < 0.001, and p < 0.001) and PD (p = 0.017, p = 0.023, p < 0.001, p = 0.001, and p < 0.001) of the total, inner-average, inner-inferior, and outer-inferior peripapillary area, and the outer-inferior macular area decreased compared to the fellow eye and normal control group, as well as the VD of the outer-average peripapillary area (p = 0.010). The PD of the outer-average peripapillary area (p = 0.003); the VD (p = 0.041, p = 0.008, p = 0.006) and the PD (p = 0.013, p < 0.001, p = 0.001) of the total, inner-inferior, and outer-average macular area; and the PD of the outer-temporal macular area (p = 0.003) were lower than the normal control group. There was no difference in the VD or PD obtained from the deep capillary plexus of the macular area among the groups. @*Conclusions@#It is useful to observe retinal capillary parameters using OCTA for patients with unilateral NTG.

3.
Article | WPRIM (Western Pacific) | ID: wpr-833273

ABSTRACT

Purpose@#To compare the thickness of the ganglion cell-inner plexiform layer (GCIPL) and the perifoveolar retinal capillary network between fellow eyes with unilateral branch retinal vein occlusion (BRVO) and healthy control eyes using optical coherence tomography angiography (OCTA). @*Methods@#Retrospective cross-sectional study including 38 patients diagnosed with unilateral BRVO and 37 control subjects. We investigated the thicknesses of the GCIPL layer using OCT, also the vascular density (VD), perfusion density (PD), area and perimeter of the foveal avascular zone (FAZ) using the OCTA. @*Results@#Patients with unilateral BRVO had a higher incidence of hypertension. In the fellow eyes of the unilateral BRVO patients, the area and perimeter of the FAZ were wider and longer than for the control eyes. There was no significant difference in the GCIPL thickness, VD and PD between the two groups. @*Conclusions@#There is no significant change in the thickness of GCIPL between 2 groups, the fellow eyes of the unilateral BRVO patients have the larger area and longer perimeter of the FAZ instead. This means macular ischemia in the follow eye when the BRVO existed. Therefore, ischemic diseases should be carefully monitored in the fellow eyes of unilateral BRVO patients.

4.
Article in English | WPRIM (Western Pacific) | ID: wpr-782506

ABSTRACT

50 years) showed lower MPOD than younger (30–49 years) subjects. But, in the healthy population, the estimated MPOD values exhibited a decreasing trend with age, but there were no significant differences according to age, after excluding patients with AMD. MPOD was significantly lower in patients with AMD than in aged healthy controls. Furthermore, hypertension, dyslipidemia, and smoking were identified as risk factors for AMD.CONCLUSION: MPOD measured with MPSII® reflects the MP density in healthy individuals and patients with dry AMD. Aging was not significantly associated with low MPOD in healthy population, but the presence of dry AMD was significantly associated with low MPOD. Then, low MPOD may be a risk factor for development of dry AMD. Furthermore, routine screening with MPS II® for ages 50 and older is thought to help detect early low MPOD and identify individuals who should take supplements.


Subject(s)
Humans , Aging , Dyslipidemias , Healthy Volunteers , Hypertension , Linear Models , Logistic Models , Macular Degeneration , Macular Pigment , Mass Screening , Methods , Photometry , Retrospective Studies , Risk Factors , Smoke , Smoking
5.
Article in Korean | WPRIM (Western Pacific) | ID: wpr-900976

ABSTRACT

Purpose@#To compare the success rate of silicone tube intubation using a lacrimal endoscope with that of endonasal dacryocystorhinostomy in adult acquired nasolacrimal duct obstruction with no canalicular obstruction. @*Methods@#Retrospective cross-sectional study including 21 patients (31 eyes) treated with silicone tube intubation using lacrimal micro-endoscope and 29 patients (37 eyes) who underwent endonasal dacryocystorhinostomy. We examined lacrimal irrigation, probing, and fluorescein dye disappearance before surgery. A total of 3 months after surgery, the silicone tube was removed. The success rates were determined based on symptoms and the results of lacrimal irrigation. @*Results@#For silicone tube intubation in the lacrimal endoscopy group, success rates 3 and 6 months after surgery were 87.1% and 71.0%, respectively. In the endonasal dacryocystorhinostomy group, they were 91.9% and 81.1%, respectively. There was no significant difference in success rates 3 and 6 months after surgery (p = 0.517 and p = 0.327, respectively). However, a significantly higher success rate (81.8%) was observed in the endonasal dacryocystorhinostomy group compared with the silicone tube intubation using lacrimal micro-endoscope group (66.7%) at 6 months after surgery if the patient had total regurgitation upon preoperative examination of lacrimal irrigation (p = 0.028). @*Conclusions@#There was no significant difference in success rates between silicone tube intubation using lacrimal endoscope and endonasal dacryocystorhinostomy in adult acquired nasolacrimal duct obstruction with no canalicular obstruction, although there was a lower success rate in patients with total nasolacrimal duct obstruction. Silicone tube intubation using lacrimal endoscope may reduce the frequencies and complications of unnecessary invasive operations and general anesthesia.

6.
Article in English | WPRIM (Western Pacific) | ID: wpr-899759

ABSTRACT

BACKGROUND@#To evaluate the macular pigment optical density (MPOD) with age in the Korean population using the Macular Pigment Screener II (MPSII®).@*METHODS@#One hundred and twenty-six eyes were retrospectively reviewed. MPOD was measured using MPSII®, which uses a heterochromatic flicker photometry method, and the estimated values were analyzed. Spearman's correlation test was used to evaluate correlations between MPOD and age. The association between MPOD and age was determined using a simple linear regression analysis. MPODs among the four groups were compared via the post hoc analysis with Bonferroni correction, MPODs between the age-related macular degeneration (AMD) group and aged-matched healthy subjects were compared via the Mann-Whitney U test. Other risk factors for AMD were identified via a logistic regression analysis.@*RESULTS@#Estimated MPOD decreased significantly with increasing age in the general population. In the simple regression analysis, a statistically significant linear regression model was observed, and the estimated values of MPOD decreased by −0.005 as age increased by 1 year. Aged (> 50 years) showed lower MPOD than younger (30–49 years) subjects. But, in the healthy population, the estimated MPOD values exhibited a decreasing trend with age, but there were no significant differences according to age, after excluding patients with AMD. MPOD was significantly lower in patients with AMD than in aged healthy controls. Furthermore, hypertension, dyslipidemia, and smoking were identified as risk factors for AMD.@*CONCLUSION@#MPOD measured with MPSII® reflects the MP density in healthy individuals and patients with dry AMD. Aging was not significantly associated with low MPOD in healthy population, but the presence of dry AMD was significantly associated with low MPOD. Then, low MPOD may be a risk factor for development of dry AMD. Furthermore, routine screening with MPS II® for ages 50 and older is thought to help detect early low MPOD and identify individuals who should take supplements.

7.
Article in Korean | WPRIM (Western Pacific) | ID: wpr-893272

ABSTRACT

Purpose@#To compare the success rate of silicone tube intubation using a lacrimal endoscope with that of endonasal dacryocystorhinostomy in adult acquired nasolacrimal duct obstruction with no canalicular obstruction. @*Methods@#Retrospective cross-sectional study including 21 patients (31 eyes) treated with silicone tube intubation using lacrimal micro-endoscope and 29 patients (37 eyes) who underwent endonasal dacryocystorhinostomy. We examined lacrimal irrigation, probing, and fluorescein dye disappearance before surgery. A total of 3 months after surgery, the silicone tube was removed. The success rates were determined based on symptoms and the results of lacrimal irrigation. @*Results@#For silicone tube intubation in the lacrimal endoscopy group, success rates 3 and 6 months after surgery were 87.1% and 71.0%, respectively. In the endonasal dacryocystorhinostomy group, they were 91.9% and 81.1%, respectively. There was no significant difference in success rates 3 and 6 months after surgery (p = 0.517 and p = 0.327, respectively). However, a significantly higher success rate (81.8%) was observed in the endonasal dacryocystorhinostomy group compared with the silicone tube intubation using lacrimal micro-endoscope group (66.7%) at 6 months after surgery if the patient had total regurgitation upon preoperative examination of lacrimal irrigation (p = 0.028). @*Conclusions@#There was no significant difference in success rates between silicone tube intubation using lacrimal endoscope and endonasal dacryocystorhinostomy in adult acquired nasolacrimal duct obstruction with no canalicular obstruction, although there was a lower success rate in patients with total nasolacrimal duct obstruction. Silicone tube intubation using lacrimal endoscope may reduce the frequencies and complications of unnecessary invasive operations and general anesthesia.

8.
Article in English | WPRIM (Western Pacific) | ID: wpr-892055

ABSTRACT

BACKGROUND@#To evaluate the macular pigment optical density (MPOD) with age in the Korean population using the Macular Pigment Screener II (MPSII®).@*METHODS@#One hundred and twenty-six eyes were retrospectively reviewed. MPOD was measured using MPSII®, which uses a heterochromatic flicker photometry method, and the estimated values were analyzed. Spearman's correlation test was used to evaluate correlations between MPOD and age. The association between MPOD and age was determined using a simple linear regression analysis. MPODs among the four groups were compared via the post hoc analysis with Bonferroni correction, MPODs between the age-related macular degeneration (AMD) group and aged-matched healthy subjects were compared via the Mann-Whitney U test. Other risk factors for AMD were identified via a logistic regression analysis.@*RESULTS@#Estimated MPOD decreased significantly with increasing age in the general population. In the simple regression analysis, a statistically significant linear regression model was observed, and the estimated values of MPOD decreased by −0.005 as age increased by 1 year. Aged (> 50 years) showed lower MPOD than younger (30–49 years) subjects. But, in the healthy population, the estimated MPOD values exhibited a decreasing trend with age, but there were no significant differences according to age, after excluding patients with AMD. MPOD was significantly lower in patients with AMD than in aged healthy controls. Furthermore, hypertension, dyslipidemia, and smoking were identified as risk factors for AMD.@*CONCLUSION@#MPOD measured with MPSII® reflects the MP density in healthy individuals and patients with dry AMD. Aging was not significantly associated with low MPOD in healthy population, but the presence of dry AMD was significantly associated with low MPOD. Then, low MPOD may be a risk factor for development of dry AMD. Furthermore, routine screening with MPS II® for ages 50 and older is thought to help detect early low MPOD and identify individuals who should take supplements.

9.
Article in Korean | WPRIM (Western Pacific) | ID: wpr-205968

ABSTRACT

Neuroaesthetics is an area of research on the essence of aesthetic experience according to the neurobiological perspective. The purpose of this article is to introduce both the important results from some studies based on neuroaesthetics and some neuroaesthetic reports in specific psychiatric disease. Aesthetic experience is thought to be a series of cognitive and affective processes for pursuing aesthetic judgment and aesthetic emotion. According to the present neuroaesthetic studies, the important domains are reward system, embodiment, aesthetic perspective in contrast with practical perspective, sublime, and so on. The neuroaesthetic approach to specific psychiatric disease is just beginning; however, case studies on the sudden appearance of artistic talents in neuropsychiatric patients have been frequently reported. We expect that neuroaesthetics is likely to continue to contribute new knowledge regarding the ultimate causes of various psychiatric diseases and the creativity of many psychiatric patients.


Subject(s)
Humans , Aptitude , Beauty , Brain , Creativity , Judgment , Reward
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