• Journal of Astronomy and Space Sciences
• /
• v.26 no.4
• /
• pp.439-450
• /
• 2009

Recurrent enhancements of relativistic electron events at geosynchronous orbit (GREEs) were observed in 2006. These GREE enhancements were associated with high-speed solar wind streams coming from the same coronal hole. For the first six months of 2006, the occurrence of GREEs has 27 day periodicity and the GREEs were enhanced with various flux levels. Several factors have been studied to be related to GREEs: (1) High speed stream, (2) Pc5 ULF wave activity, (3) Southward IMF Bz, (4) substorm occurrence, (5) Whistler mode chorus wave, and (6) Dynamic pressure. In this paper, we have examined the effectiveness about those parameters in selected periods.

• Archives of Plastic Surgery
• /
• v.37 no.1
• /
• pp.46-51
• /
• 2010

Purpose: The loss of web space is caused by congenital syndactyly or acquired burn injury, trauma or surgery. Numerous surgical procedures have been described for restoration of the web space. Local flaps are usually preferred because of the easiness to perform and tolerable postoperative outcome. Among the various local flaps, the authors introduce V-M plasty for correction of web space contracture and syndactyly. Method: From March 2007 to Jun 2008, 4 patients underwent V-M plasty for correction of web space contracture and syndactyly. V-M plasty consists of 3 distinct triangular flaps. One triangular flap is designed next to the web region on the dorsal site of the hand, whereas the remaining 2 triangular flaps are placed on the volar site. The dorsal triangular flap is then placed between the volar adjacent triangular flaps. At the end of the operation, the involved fingers or toes are positioned in abduction to avoid kinking of the triangular flaps. Result: All the patients gained web functions with good esthetic appearance without any recurrence or complications. Mean follow-up was 8 months. Conclusion: V-M plasty is a safe, easy and rapid procedure to design and apply by using local tissues without the needs for a skin graft or risk of linear scarring and recurrence. The authors advise this versatile technique both in primary and recurrent cases of web space contracture and syndactyly.

• Korean Journal of Radiology
• /
• v.2 no.4
• /
• pp.204-209
• /
• 2001

Objective: To determine the feasibility of transcaval transjugular intrahepatic portosystemic shunt (TIPS) in patients with occluded previous TIPS. Materials and Methods: Between February 1996 and December 2000 we performed five transcaval TIPS procedures in four patients with recurrent gastric cardiac variceal bleeding. All four had occluded TIPS, which was between the hepatic and portal vein. The interval between initial TIPS placement and revisional procedures with transcaval TIPS varied between three and 31 months; one patient underwent transcaval TIPS twice, with a 31-month interval. After revision of the occluded shunt failed, direct cavoportal puncture at the retrohepatic segment of the IVC was attempted. Results: Transcaval TIPS placement was technically successful in all cases. In three, tractography revealed slight leakage of contrast materials into hepatic subcapsular or subdiaphragmatic pericaval space. There was no evidence of propagation of extravasated contrast materials through the retroperitoneal space or spillage into the peritoneal space. After the tract was dilated by a bare stent, no patient experienced trans-stent bleeding and no serious procedure-related complications occurred. After successful shunt creation, variceal bleeding ceased in all patients. Conclusion: Transcaval TIPS placement is an effective and safe alternative treatment in patients with occluded previous TIPS and no hepatic veins suitable for new TIPS.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.29 no.4
• /
• pp.418-425
• /
• 2013

This case report describes about recurrent herpetic stomatitis mimicking post-root resection complication. A 49 year-old male patient was diagnosed vertical root fracture of the mesiobuccal root of his left maxillary first molar (#26). The mesiobuccal root was resected following root canal treatment of the same tooth. 19 months later, the patient presented with pain on left hard palate after a barbecue party. Intra oral examination revealed a gum boil-like blister at the hard palate corresponding to the apex of the palatal root of #26. On clinical examination, there was bleeding on probing and the periodontal pocket depth was measured less than 5 mm with no tooth mobility. On a periapical radiograph, periodontal ligament space widening was observed. Tracing the sinus tract with gutta percha cone was attempted, however, it was impossible. Extending the field of vision, small multiple round ulcerations were observed at the palate front which caused pain to the patient. Therefore, the pain was considered a non odontogenic and the patient was referred to the department of oral medicine. The patient was diagnosed recurrent herpetic stomatitis and after 3 days of antiviral medication, the pain and ulceration were subsided.

• The Journal of Korean Institute of Next Generation Computing
• /
• v.14 no.6
• /
• pp.57-65
• /
• 2018

Conventional RF signal-based indoor localization techniques such as BLE or Wi-Fi based fingerprinting method show considerable localization errors even in small-scale indoor environments due to unstable received signal strength(RSS) of RF signals. Therefore, it is difficult to apply the existing RF-based fingerprinting techniques to large-scale indoor environments such as airports and department stores. In this paper, instead of RF signal we use the geomagnetic sensor signal for indoor localization, whose signal strength is more stable than RF RSS. Although similar geomagnetic field values exist in indoor space, an object movement would experience a unique sequence of the geomagnetic field signals as the movement continues. We use a deep neural network model called the recurrent neural network (RNN), which is effective in recognizing time-varying sequences of sensor data, to track the user's location and movement path. To evaluate the performance of the proposed geomagnetic field based indoor positioning system (IPS), we constructed a magnetic field map for a campus testbed of about $94m{\times}26$ dimension and trained RNN using various potential movement paths and their location data extracted from the magnetic field map. By adjusting various hyperparameters, we could achieve an average localization error of 1.20 meters in the testbed.

• The Bulletin of The Korean Astronomical Society
• /
• v.38 no.1
• /
• pp.63.2-63.2
• /
• 2013

We have investigated the EUV coronal jets observed by Solar Dynamic Observatory (SDO) / Atmospheric Imaging Assembly (AIA). From the Heliophysics Events Knowledgebase (HEK), we consider all recorded 40 EUV jets in $171{\AA}$ from May 2010 to July 2011 and use 19 jets whose location can be clearly identified, excluding limb events because of the ambiguity of their positions. According to the positions of their roots, these coronal jets are classified into two types: bright point jet (BPJ, 9 jets) and active region boundary jet (ABJ, 10 jets). BPJs are located at the top of bright points and ABJs at the boundaries of active regions. There are significant differences in speed and size between two types. Here the speed and size of a jet are assumed to be its maximum values in the case that the jet has several ejections. The average speed and size of 9 BPJs are about 110 km/s and 69,000km, respectively. The average speed and size of 10 ABJs are about 660 km/s and 194,000 km, respectively. The speed distribution of ABJs has two peaks at about 270 km/s and 1700 km/s. It is very interesting to note that three ABJs have very high speeds larger than 1600 km/s and they are all composed of a group of recurrent jets with low and high speed at the same location. In addition, we are investigating these events in other wavelengths and compare their characteristics.

• Archives of Craniofacial Surgery
• /
• v.9 no.2
• /
• pp.110-113
• /
• 2008

Purpose: The jejunal free flap is the most standard and reliable procedure of reconstruction of the circumferential pharyngoesophageal defect because it provides pliable, elastic, secreting mucosa and posses reliable vascular anatomy. In this report, the authors introduce the modification of jejunal free flap for decreasing the complications in fatty complicated patients. Method: After harvesting the jejunum with mesentery and mesenteric vessels, both ends of jejunum were excised remaining the mesenteric portion. The jejunal portion of this composite flap was placed to reconstruct esophagopharyngeal defect area and the mesenteric portion was used to obliterate the dead space at paratracheal region and to cover the vital structure and the vascular anastomotic region. Result: A 72 year-old man with recurrent hypopharyngeal cancer who had about 15 cm sized circumferential pharyngoesophageal defect after total pharyngectomy was reconstructed with jejunomesenteric composite free flap without any complications. Conclusion: The mesenteric flaps at both side of jejunomesenteric composite free flap provide the advantages that could obliterate dead space, that could provide cover for the vital cervical vascular structure in case of vascularity was compromised due to previous radiation therapy, and that could preserve as much vascularity at both ends of jejunal flap as possible.

• Archives of Plastic Surgery
• /
• v.36 no.5
• /
• pp.670-673
• /
• 2009

Purpose: Epidural abscesses and subdural empyemas after craniotomy are uncommon, potentially lethal, complications of neurosurgery. Patients with these complications may be difficult to manage and dural reconstruction in these patients are challenging. Methods: A 28 - year - old female patient showed recurrent intracranial infection after craniotomy for evacuation of a arachnoid cyst and subdural hematoma. Despite prolonged systemic antibiotic administration and a debridement of the subdural space, infection persisted, as evidenced by persistent fever, an elevated WBC count, CSF leakage, low CSF glucose level, and purulent wound discharge. The authors removed the previously applied lyophilized dura and transferred free omental flap to reconstruct the dura, obliterate the cyst and cover the cerebral hemisphere in the craniotomy defect. Microvascular anastomosis was between gastroepiploic and superficial temporal vessels. Results: The postoperative course was uneventful and flap survival was excellent. The infection - resistant omental tissue allowed sufficient blood circulation and dead space control. The patient was discharged 1 month after surgery and wound discharge or recurrence was absent during 13 months of follow up periods. Conclusion: The use of vascularized free omentum proved useful in cases of intractable cranial wound infection and cerebrospinal fluid leakages.

• Journal of Broadcast Engineering
• /
• v.27 no.6
• /
• pp.885-896
• /
• 2022

Motor failure in manufacturing plays an important role in future A/S and reliability. Motor failure is detected by measuring sound, current, and vibration. For the data used in this paper, the sound of the car's side mirror motor gear box was used. Motor sound consists of three classes. Sound data is input to the network model through a conversion process through MelSpectrogram. In this paper, various methods were applied, such as data augmentation to improve the performance of classifying fault motors and various methods according to class imbalance were applied resampling, reweighting adjustment, change of loss function and representation learning and classification into two stages. In addition, the curriculum learning method and self-space learning method were compared through a total of five network models such as Bidirectional LSTM Attention, Convolutional Recurrent Neural Network, Multi-Head Attention, Bidirectional Temporal Convolution Network, and Convolution Neural Network, and the optimal configuration was found for motor sound classification.

• Proceedings of the KSRS Conference
• /
• 2005.10a
• /
• pp.462-465
• /
• 2005

The ITT Industry's Commercial Advanced Geo-Imager (CAGI) which is a recurrent version of imagers used in the GOES series was selected as the COMS Meteorological Imager (MI). The ITT Imager can conduct some special observation such as the space look, blackbody observation, and star sensing regularly or irregularly for its radiometric quality control. Because the GOES-9 which uses an ITT Imager has become operational over the Western Pacific and Eastern Asia positioned at 155 degrees East, the reception of the GOES-9 data is available in Korea. As a step of preparing the COMS MI operation, we conduct the analysis of the GOES-9 imager raw data and operation procedures and compare them with contents of the ITT Imager's manual.