• Journal of Astronomy and Space Sciences
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• v.38 no.2
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• pp.119-134
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• 2021

The data set collected during the night of the discovery of a minor body constitutes a too-short arc (TSA), resulting in failure of the differential correction procedure. This makes it necessary to recover the object during subsequent nights to gather more observations that will allow a preliminary orbit to be calculated. In this work, we present a recovery technique based on sampling the admissible region (AdRe) by the constrained Delaunay triangulation. We construct the AdRe in its topocentric and geocentric variants, using logarithmic and exponential metrics, for the following near-Earth-asteroids: (3122) Florence, (3200) Phaethon, 2003 GW, (1864) Daedalus, 2003 BH84 and 1977 QQ5; and the main-belt asteroids: (1738) Oosterhoff, (4690) Strasbourg, (555) Norma, 2006 SO375, 2003 GE55 and (32811) Apisaon. Using our sampling technique, we established the ephemeris region for these objects, using intervals of observation from 25 minutes up to 2 hours, with propagation times from 1 up to 47 days. All these objects were recoverable in a field of vision of 95' × 72', except for (3122) Florence and (3200) Phaethon, since they were observed during their closest approach to the Earth. In the case of 2006 SO375, we performed an additional test with only two observations separated by 2 minutes, achieving a recovery of up to 28 days after its discovery, which demonstrates the potential of our technique.

• Archives of Plastic Surgery
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• v.50 no.2
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• pp.148-152
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• 2023

Soft tissue filler injection is the second most common nonsurgical cosmetic procedure. Despite the safety of fillers, as use has grown, so has the number of patients affected by adverse events. Ophthalmoplegia following cosmetic filler injection is a rare complication, mostly occurring after injection to the glabella, nasolabial fold, periorbital, and lateral nasal site. In all cases where ophthalmoplegia has been reported following fillers, patients have simultaneously experienced vision loss and other ocular symptoms. We report a case of isolated acute ophthalmoplegia following hyaluronic acid injection solely in the temple region. A 40-year-old woman, 3 hours after the procedure, presented to our hospital with left eye ophthalmoplegia, ptosis, and hypotropia. Treatment started with hyaluronidase, steroids, and anticoagulants. After 4 weeks, left eye ophthalmoplegia remained unchanged, and through a 10-week follow-up, all left ocular movements improved, and only mild hypotropia and ptosis persisted. This case report shows that ophthalmoplegia may also happen with temple region filler injections. We also review available prevention techniques and treatments to avoid such complications when performing soft tissue fillers for gaunt appearance correction.

• Journal of Korean Ophthalmic Optics Society
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• v.15 no.2
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• pp.145-150
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• 2010

Purpose: In this study we investigated the correlation between the effect of myopia correction and the change of corneal eccentricity using reverse geometry lens. Methods: The 23 students (46 eyes) continuously wearing reverse geometry lens during 3 months were divided into Group I and Group II by different parameter fitting methods of wearing Reverse Geometry Lens. We measured a corneal eccentricity for Group I and Group II at $10^{\circ}$, $20^{\circ}$, and $30^{\circ}$ positions from corneal apex before wearing reverse geometry lens, 1 week, 1 month, and 3 months after wearing reverse geometry lens. We also measured an uncorrected visual acuity, a spherical equivalent, and a corneal radius and analyzed the correlation between them and the change of corneal eccentricity using statistical significance test. Results: There were the statistical significances of a change of corneal eccentricity (p=0.03, t=-2.29) for Group I and Group II at 10 position from corneal apex in a week after wearing reverse geometry lens, but were not those (p>0.05) in 1 month, and 3 months after wearing reverse geometry lens. There were the statistical significances of correlation between the change of corneal eccentricity and a corrected visual acuity, and a corneal radius, respectively. Particularly, the high correlation between the change of corneal eccentricity and a corrected visual acuity (r=-0.36, p=0.00, t=6.5), and a spherical equivalent (r=-0.72, p=0.00, t=-70.5) for Group II in a week after wearing reverse geometry lens showed. Conclusions: We knew from these results that the high correlation between the effect of myopia correction and the change of corneal eccentricity in a week after wearing reverse geometry lens represented.

• Journal of Korean Ophthalmic Optics Society
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• v.17 no.3
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• pp.265-272
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• 2012

Purpose: To compare the results on myopia correction with reverse geometry lenses, effects of wearing reverse geometry lenses were evaluated for the children with low-level and high-level myopia. Methods: The research investigated the corrective effects of having worn reverse geometry lenses for one week, one month, three months and six months on a total of thirty-six persons (sixty-two eyes) between the ages of seven and fifteen, divided into three groups by the degree of their myopia; nineteen eyes(Group One) with myopia of -2.00 D and under, twenty-eight eyes(Group Two) with myopia between -2.25 D and -4 D, and fifteen eyes(Group Three) with myopia of -4.25 D and above; as shown by changes in uncorrected vision and the degree of refraction in the corneal topography, and tested for statistical similarity among the pursued results. Results: After wearing reverse geometry lenses, Group One showed an improvement in vision of 0.5, from 0.45 to 0.95, after one week, and improvements to 0.91 after one month and 1.02 after three months but, after six months, the group's vision regressed to 0.95. Group Two showed an improvement in vision of 0.43, from 0.34 to 0.77, after one week of wearing and to 0.91 after one month, to 0.97 after three months and this was statistically maintained through the remainder of six months. Group Three showed an improvement in vision of 0.55, from 0.15 to 0.7, after wearing for one week, to 0.87 after one month and to 0.91 after three months but saw a regression to 0.86 after six months. The average Sim K (simulated keratometry reading) value for Group One started from $42.84{\pm}1.17D$ and decreased to $41.48{\pm}0.98D$ after one week of wearing and continued declining through three months before increasing during the remainder of six months. Group Two began from $42.91{\pm}1.57D$ and recorded $41.78{\pm}1.58 D$ after one week, continuing the decline through three months before increasing during the remainder of six months. Group Three began at $42.64{\pm}1.64D$ and showed its Sim K value decrease to $40.77{\pm}1.20D$ after one week of wearing, increase after one month and decrease after three months and continue the decline through the remainder of six months. Conclusions: From the results of this study, wearing reverse geometry lenses had myopia-correcting effects after one week of wearing. Although there were variations in the time for such effect to take place but myopia-correcting effects were evident in all test groups.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.6
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• pp.107-116
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• 2015

In compliance with digital device growth, the proliferation of high-tech computers, the availability of high quality and inexpensive video cameras, the demands for automated video analysis is increasing, especially in field of intelligent monitor system, video compression and robot vision. That is why object tracking of computer vision comes into the spotlight. Tracking is the process of locating a moving object over time using a camera. The consideration of object's scale, rotation and shape deformation is the most important thing in robust object tracking. In this paper, we propose a robust object tracking scheme using Random Forest. Specifically, an object detection scheme based on region covariance and ZNCC(zeros mean normalized cross correlation) is adopted for estimating accurate object location. Next, the detected region will be divided into five regions for random forest-based learning. The five regions are verified by random forest. The verified regions are put into the model pool. Finally, the input model is updated for the object location correction when the region does not contain the object. The experiments shows that the proposed method produces better accurate performance with respect to object location than the existing methods.

• The Journal of the Korea Contents Association
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• v.21 no.6
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• pp.701-715
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• 2021

The drastic advance of recent deep learning technologies is heavily dependent on training datasets which are essential to train models by themselves with less human efforts. In comparison with the work to design deep learning models, preparing datasets is a long haul; at the moment, in the domain of vision intelligent, datasets are still being made by handwork requiring a lot of time and efforts, where workers need to directly make labels on each image usually with GUI-based labeling tools. In this paper, we overview the current status of vision datasets focusing on what datasets are being shared and how they are prepared with various labeling tools. Particularly, in order to relieve the repetitive and tiring labeling work, we present an interactive smart image annotating system with which the annotation work can be transformed from the direct human-only manual labeling to a correction-after-checking by means of a support of automatic labeling. In an experiment, we show that automatic labeling can greatly improve the productivity of datasets especially reducing time and efforts to specify regions of objects found in images. Finally, we discuss critical issues that we faced in the experiment to our annotation system and describe future work to raise the productivity of image datasets creation for accelerating AI technology.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.3
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• pp.143-149
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• 2018

Recently, due to the large-scale damage of natural disasters caused by global climate change, a monitoring system applying remote sensing technology is being constructed in disaster areas. Among remote sensing platforms, the drone has been actively used in the private sector due to recent technological developments, and has been applied in the disaster areas owing to advantages such as timeliness and economical efficiency. This paper deals with the development of a preprocessing system that can map the drone image data in a near-real time manner as a basis for constructing the disaster monitoring system using the drones. For the research purpose, our system is based on the SURF algorithm which is one of the computer vision technologies. This system aims to performs the desired correction through the feature point matching technique between reference images and shot images. The study area is selected as the lower part of the Gahwa River and the Daecheong dam basin. The former area has many characteristic points for matching whereas the latter area has a relatively low number of difference, so it is possible to effectively test whether the system can be applied in various environments. The results show that the accuracy of the geometric correction is 0.6m and 1.7m respectively, in both areas, and the processing time is about 30 seconds per 1 scene. This indicates that the applicability of this study may be high in disaster areas requiring timeliness. However, in case of no reference image or low-level accuracy, the results entail the limit of the decreased calibration.

• Journal of Korean Neurosurgical Society
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• v.29 no.1
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• pp.58-65
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• 2000

Objective : Thoracolumbar junction is second most common level of injury next to cervical spine. The object of this study is to study the usefulness of surgical titanium mesh instead of bone graft, as well as to evaluate the correction of spinal deformity and safety of early ambulation in patients with injury at thoracolumbar junction. Patients and Methods : This review included 51 patients who were operated from July 1994 to December 1997. The injured spine is considered to be unstable, if it shows involvement of two or more columns, translatory displacement more than 3.5mm, decrease more than 35% in height of vertebral body and progression of malalignment in serial X-ray. The decision to operate was determined by (1) compression of spinal cord or cauda eguina, (2) unstable fracture, (3) malalignment and (4) fracture dislocation. The procedure consisted of anterior decompression through corpectomy and internal fixation with anterior instrument and surgical titanium mesh which was impacted with gathered bone chip from corpectomy. Results : Fifty-one patients were followed up for at least 12 months. The main causes of injury were fall and vehicle accident. The twelfth thoracic and the first and the second lumbar vertebrae were frequently involved. Complete neural decompression was possible under direct vision in all cases. Kyphotic angulation occurred in a patient. Radiologic evaluation showed correction of deformity and no distortion or loosening of surgical titanium mesh with satisfactory fixation postoperatively. Conclusions : We could obtain neurological improvement, relief of pain, immediate stabilization and early return to normal activities postoperatively. Based on these results, authors recommend anterior decompression and internal fixation with surgical titanium mesh in thoracolumbar unstable spine injuries.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.22 no.3
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• pp.57-68
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• 2017

Continuous monitoring of spatial and temporal changes in key marine environmental parameters such as SST (sea surface temperature) near IORS (Ieodo Ocean Research Station) is demanded to investigate the ocean ecosystem, climate change, and sea-air interaction processes. In this study, we aimed to develop the system for continuously measuring SST using a TIR (thermal infrared) sensor mounted at the IORS. New SST algorithm is developed to provide SST of better quality that includes automatic atmospheric correction and emissivity calculation for different oceanic conditions. Then, the TIR-based SST products were validated against in-situ water temperature measurements during May 17-26, 2015 and July 15-18, 2015 at the IORS, yielding the accuracy of 0.72-0.85 R-square, and $0.37-0.90^{\circ}C$ RMSE. This TIR-based SST observing system can be installed easily at similar Ocean Research Stations such as Sinan Gageocho and Ongjin Socheongcho, which provide a vision to be utilized as calibration site for SST remotely sensed from satellites to be launched in future.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.2
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• pp.207-216
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• 2014

Purpose: In this study, we analyzed visual acuity of children according to the rearing of the type of parents. Methods: We have done a comparative analysis about before and after of corrected visual acuity according to the wearing actual conditions with the Korean National Health and Nutrition Examination Survey 2010 document. Results: Visual acuity before correction of twoparent family's children was 0.91, single parent family's children was 0.83, grandparents family's children was 0.77 in low income and twoparent family's children was 0.80, single parent family's children was 0.77, grandparents family's children was 0.50 in lower middle income. Conclusions: In the rearing of low-income children, the lack of attention to visual acuity management according to the type of parents leads to a failing of visual acuity in myopia. The role of the parents is very important during this time period, so it is necessary to provide social interest giving decline prevention of vision.