• The korean journal of orthodontics
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• v.29 no.6 s.77
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• pp.673-688
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• 1999

This study was conducted in order to analyze the mechanical characteristics of multiloop edgewise archwire (MEAW). The purposes were 1) to compare load deflection rate (LDR) of MEAW with that of various other arch wires in the individual interbracket span, 2) to compare the wire stiffness in the interbracket span with that in the multi-L-loop region (the span from distal border of the bracket of the lateral incisor to the mesial border of the buccal tube of the second molar), and 3) to verify the experimental results with theoretically derived formula. The single L-loops of five different horizontal lengths and multi-L-loops for the upper and lower arches were made out of .$016\times.022$ permachrome stainless steel wire. Straight segment of plain stainless steel, TMA and NiTi wire of the same dimension were prepared. The LDR was measured using Instron model 4466 with the load cell of 50N capacity at cross head speed of 1.0mm/min, and maximum deflection of 1.0mm. Five specimens were tested under each experimental condition. The wire stiffness number for each interbracket region and multi-L-loop region was calculated from the LDR and the interbracket spans. By dividing the theoretical model of multi-L-loop into 35 linear segments, the energy stored in each segment was obtained. Then the LDR and wire stiffness of single L-loop and multi-L-loop were calculated and compared. The findings were as follows : 1) The average LDR of MEAW in the individual interbracket region was 1/1.53 of that of the NiTi,1/2.47 of TMA and 1/5.16 of the plain stainless steel wire. 2) The wire stiffness of MEAW in the multi-L-loop region was 1.53 times larger than that in the interbracket region, and the LDR was almost twice as large as that of NiTi in that region. 3) According to the theoretically derived equation, the wire stiffness of the single L-loop was lower than that of multi-L-loop. The results of this study suggest that MEAW has the unique mechanical Property which could allow individual tooth movement and transmit elastic force effectively through the entire arch wire.

• Archives of Plastic Surgery
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• v.38 no.5
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• pp.642-648
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• 2011

Purpose: The recent advances in microsurgical techniques and their refinement over the past decade have greatly expanded the indications for digital replantations and have enabled us to salvage severed fingers more often. Many studies have reported greater than 80% viability rates in replantation surgery with functional results. However, replantation of multi-level amputations still remain a challenging problem and the decision of whether or not to replant an amputated part is difficult even for an experienced reconstructive surgeon because the ultimate functional result is unpredictable. Methods: Between January of 2002 and May of 2008, we treated 10 multi-level amputated digits of 7 patients. After brachial plexus block, meticulous replantation procedure was performed under microscopic magnification. Postoperatively, hand elevation, heat lamp, drug therapy and hyperbaric oxygen therapy were applied with careful observation of digital circulation. Early rehabilitation protocol was performed for functional improvement. Results: Among the 19 amputated segments of 10 digits, 16 segments survived completely without any complications. Overall survival rate was 84%. Complete necrosis of one finger tip segment and partial necrosis of two distal amputated segments developed and subsequent surgical interventions such as groin flap, local advancement flap and skin graft were performed. The overall result was functionally and aesthetically satisfactory. Conclusion: We experienced successful replantations of multi-level amputated digits. When we encounter a multi-level amputation, the key question is whether or not it is a contraindication to replantation. Despite the demand for skillful microsurgical technique and longer operative time, the authors' results prove it is worth attempting replantations in multi-level amputation because of the superiority in aesthetic and functional results.

• Journal of Korean Neurosurgical Society
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• v.46 no.4
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• pp.285-291
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• 2009

Objective : This study examined the change of range of motion (ROM) at the segments within the dynamic posterior stabilization, segments above and below the system, the clinical course and analyzed the factors influencing them. Methods : This study included a consecutive 27 patients who underwent one-level to three-level dynamic stabilization with Bioflex system at our institute. All of these patients with degenerative disc disease underwent decompressive laminectomy with/without discectomy and dynamic stabilization with Bioflex system at the laminectomy level without fusion. Visual analogue scale (VAS) scores for back and leg pain, whole lumbar lordosis (from L1 to S1), ROMs from preoperative, immediate postoperative, 1.5, 3, 6, 12 months at whole lumbar (from L1 to S1), each instrumented levels, and one segment above and below this instrumentation were evaluated. Results : VAS scores for leg and back pain decreased significantly throughout the whole study period. Whole lumbar lordosis remained within preoperative range, ROM of whole lumbar and instrumented levels showed a significant decrease. ROM of one level upper and lower to the instrumentation increased, but statistically invalid. There were also 5 cases of complications related with the fixation system. Conclusion : Bioflex posterior dynamic stabilization system supports operation-induced unstable, destroyed segments and assists in physiological motion and stabilization at the instrumented level, decrease back and leg pain, maintain preoperative lumbar lordotic angle and reduce ROM of whole lumbar and instrumented segments. Prevention of adjacent segment degeneration and complication rates are something to be reconsidered through longer follow up period.

• The Journal of the Korea Contents Association
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• v.8 no.7
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• pp.35-42
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• 2008

The proposed scheme in this paper can search multi-links efficiently using the depth priority method based on hop count instead of searching the all links. To do this, we proposed a modified line segment scheme using two line segment method. The scheme represents two points which consist of delay-bandwidth pair to reduce topology information and provide a flexibility to the multiple-links aggregation. And we apply it to current spanning tree topology aggregation. To evaluate performance of the proposed scheme, we compare/analyze the current method with the proposed scheme with respect to call success rate, access time and crankback rate. Simulation result analysis showed the proposed spanning tree topology aggregation scheme presents the better performance than existing scheme.

• Journal of Korean Society for Atmospheric Environment
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• v.34 no.5
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• pp.735-747
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• 2018

Rainfall depth is an important meteorological information. Generally, high spatial resolution rainfall data such as road-level rainfall data are more beneficial. However, it is expensive to set up sufficient Automatic Weather Systems to get the road-level rainfall data. In this paper, we propose to use deep learning to recognize rainfall depth from road surveillance videos. To achieve this goal, we collect a new video dataset and propose a procedure to calculate refined rainfall depth from the original meteorological data. We also propose to utilize the differential frame as well as the optical flow image for better recognition of rainfall depth. Under the Temporal Segment Networks framework, the experimental results show that the combination of the video frame and the differential frame is a superior solution for the rainfall depth recognition. The final model is able to achieve high performance in the single-location low sensitivity classification task and reasonable accuracy in the higher sensitivity classification task for both the single-location and the multi-location case.

• Proceedings of the KSMRM Conference
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• 2003.10a
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• pp.45-45
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• 2003

To evaluate remodeling of infarcted myocardium with contrast-enhanced MRI (co-MRI) at true end-diastole (ED) MRI was performed with a Gyroscan Intera (1.5 Tesla, Philips, Netherlands) in 13 patients with acute subendocardial myocardial infarction. The First exam was done 0-15 days (mean 5.2days) after symptom onset and the second exam 28-88days (mean 49 days) after the first exam. Ce-MRI encompassing the entire left ventricle was performed with a multi-shot, turbo-field-echo, breath-hold sequence and a non-selective, inversion prepulse 10 minutes after the intravenous injection of Gd-DTPA at a dose of 0.2 mmol/kg body weight. To allow the long TD, ECG synchronization should use two RR-intervals for one acquisition of a segment of k-space by setting the heart rate to half that of the true heart rate. Trigger delay time (TD) was adjusted to the RR-interval for true end-diastolic imaging. The other typical parameters were TR=5.4ms, TE=1.6ms, voxel size=1.37${\times}$1.37${\times}$10mm, k-space data segmented into 8 segments with 32 lines of segment per two cycles over 16 cardiac circles. The thickness of hyperenhanced myocardium and epicardially nonenhanced myocardium were followed.

• Proceedings of the KSMRM Conference
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• 2003.10a
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• pp.92-92
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• 2003

To evaluate remodeling of infarcted myocardium with contrast-enhanced MRI (co-MRI) at true end-diastole (ED) MRI was performed with a Gyroscan Intera (1.5 Tesla, Philips, Netherlands) in 13 patients with acute subendocardial myocardial infarction. The First exam was done 0-15 days (mean 5.2days) after symptom onset and the second exam 28-88days (mean 49 days) after the first exam. Ce-MRI encompassing the entire left ventricle was peformed with a multi-shot, turbo-field-echo, breath-hold sequence and a non-selective, inversion prepulse 10 minutes after the intravenous injection of Gd-DTPA at a dose of 0.2 mmol/kg body weight. To allow the long TD, ECG synchronization should use two RR-intervals for one acquisition of a segment of k-space by setting the heart rate to half that of the true heart rate. Trigger delay time (TD) was adjusted to the RR-interval for true end-diastolic imaging. The other typical parameters were TR=5.4ms, TE=1.6ms, voxel size=1.37$\times$1.37$\times$10mm, k-space data segmented into 8 segments with 32 lines of segment per two cycles over 16 cardiac cycles. The thickness of hyperenhanced myocardium and epicardially nonenhanced myocardium were followed.

• Journal of Korea Multimedia Society
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• v.7 no.11
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• pp.1556-1563
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• 2004

In this paper, we propose an efficient full mesh topology aggregation method in PNNI networks. The proposed scheme can search multi-links efficiently using the depth priority method based on hop count instead of searching the all links. To do this, we propose a modified line segment algorithm using two line segment method that represents two points which consist of delay-bandwidth pair to reduce topology information and provide a flexibility to the multiple-links aggregation. And we apply it to current full mesh topology aggregation. To evaluate performance of the proposed scheme, we compare/analyze the current method with the proposed scheme with respect to call success rate, access time and crank back rate. The result is that the proposed scheme is better than the current scheme in performance.

• Journal of the Institute of Convergence Signal Processing
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• v.17 no.2
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• pp.67-70
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• 2016

This paper discusses a graphic user interface(GUI) for the concealed target segmentation. The human subject hiding a metal gun is captured by the passive millimeter wave(MMW) imaging system. The imaging system operates on the regime of 8 mm wavelength. The MMW image is analyzed by the multi-level segmentation to segment and identify a concealed weapon under clothing. The histogram of the passive MMW image is modeled with the Gaussian mixture distribution. LBG vector quantization(VQ) and expectation and maximization(EM) algorithms are sequentially applied to segment the body and the object area. In the experiment, the GUI is implemented by the MFC(Microsoft Foundation Class) and the OpenCV(Computer Vision) libraries and tested in real-time showing the efficiency of the system.

• Journal of the Korean Society of Food Culture
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• v.34 no.3
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• pp.277-283
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• 2019

This study explore the market segmentation based on beer consumers' purchase motivation 1) to analyze beer consumers and markets more closely and 2) to demonstrate the characteristics of each market segment and contribute to marketing strategies with beer consumer segment. Using -administrated questionnaires asked questions recognizable beer purchase within 6 months by over 20-years-olds, this study 201 surveys online 22 days. The results as follows: beer consumers' purchase motivation consisted of three factors enhancement, social orientation, and value enhancement. Cluster analysis based on beer purchase showed that there were three groups motivation multi-motivation and motivation group based on average value of beer purchase motive factors and relative load per factor. demographic,beer drinking characteristics and group difference according to cluster gender and monthly average income, and beer drinking characteristics also significantly different by preferred beer, preferred beer type, occasion and drinking place.