• Journal of the korean academy of Pediatric Dentistry
• /
• v.38 no.4
• /
• pp.391-398
• /
• 2011

The infraocclusion usually occurs in the mixed-dentition stage, and it is commonly accepted that the cause of the infraocclusion is ankylosis. The treatment options for patient with infraocclusion of primary molars are observation, restoration or surgical removal of the affected teeth. If the successors are present, most of the infraoccluded and ankylosed primary molars may occur normally. However, when the permanent successors are absent and the progression of infraocclusion is found, affected teeth may need to be extracted. In the case of infraocclusion which can cause vertical alveolar defect due to ankylosis, extraction before growth spurt should be performed for the future prosthetic treatment. A six-year-old female had the ankylosis and infraocclusion of multiple primary molars and congenital missing of premolars. The affected primary molars were extracted before growth spurt to avoid a significant vertical ridge defect and to promote the vertical development of alveolar bone, and the result was observed for many years. The purpose of this report is to report the management of multiple infraoccluded primary molars without permanent successors in a young patient.

• Journal of Chest Surgery
• /
• v.46 no.6
• /
• pp.482-485
• /
• 2013

Plasmacytoma is a plasma cell neoplasm that locally infiltrates a bone or spreads to extramedullary areas. A new World Health Organization criterion defines solitary plasmacytoma of bone as a localized bone tumor consisting of plasma cells identical to those seen in plasma cell myeloma, which is manifested as a solitary osteolytic lesion in a radiological evaluation. Primary tumors of the sternum are generally malignant, and solitary plasmacytomas of the sternum are very rare tumors. We present herein the case of a patient who had a primary sternal tumor with solitary plasmacytoma and no evidence of multiple myeloma.

• Journal of electromagnetic engineering and science
• /
• v.10 no.3
• /
• pp.99-103
• /
• 2010

Motivated by recent works on spectrum-sharing systems, this paper investigates the effects of transmit diversity on the peak interference power limited cognitive radio(CR) networks. In particular, we derive the ergodic and outage capacities of a spectrum-sharing system with multiple transmit-antennas. To derive the capacities, peak interference power constraint is imposed to protect the primary receiver. In a CR transmitter and receiver pair with multiple antennas at the transmitter side, the allowable transmit power is distributed over the transmit-antennas to achieve transmit diversity at the receiver. We investigate the effect of this power distribution when a peak interference power constraint is imposed to protect the primary receiver. We show that the transmit diversity does not improve the ergodic capacity compared to the single-antenna system. On the other hand, the transmit diversity significantly improves the outage capacity. For example, two transmit-antennas improve the outage capacity 10 times compared to the single-antenna with a 0 dB interference constraint.

• Journal of Chest Surgery
• /
• v.51 no.3
• /
• pp.220-222
• /
• 2018

Myopericytoma is a benign tumor that occurs in soft tissues. Myopericytoma in the lungs is very rare. We report the case of a 63-year-old woman presenting with cavitary masses in the left lung and multiple tiny nodules in both lungs. She underwent surgery, and a histological examination revealed primary pulmonary myopericytoma.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.14 no.3
• /
• pp.77-85
• /
• 2018

Multi-User Multiple-Input Multiple-Output (MU-MIMO) is the core technology for improving the channel capacity compared to Single-User MIMO (SU-MIMO) by using multiuser gain and spatial diversity. Key problem for the MU-MIMO is the user selection which is the grouping the users optimally. To solve this problem, we adopt Extreme Value Theory (EVT) at the beginning of the proposed algorithm, which defines a primary user set instead of a single user that has maximum channel power according to a predetermined threshold. Each user in the primary set is then paired with all of the users in the system to define user groups. By comparing these user groups, the group that produces a maximum sum rate can be determined. Through computer simulations, we have found that the proposed method outperforms the conventional technique yielding a sum rate that is 0.81 bps/Hz higher when the transmit signal to noise ratio (SNR) is 30 dB and the total number of users is 100.

• The Transactions of the Korean Institute of Electrical Engineers B
• /
• v.55 no.3
• /
• pp.182-188
• /
• 2006

Contactless power system is base on power transmission by magnetic force. The transformer loss is large because it separated with the gap. Also the system has unstable factor, since the parameters in the secondary can vary with the system movement. This paper proposes light train power transmission system using contactless transformer with multiple primary winding. To increase the system efficiency and to obtain the stable power transmission to the dynamic load, a resonant inverter is adopted. The proposed system was verified by the simulation using Spice and Maxwell. The designed contactless power transmission system is implemented for 5[kW] class and experimental results are discussed.

• Journal of Chest Surgery
• /
• v.54 no.5
• /
• pp.422-424
• /
• 2021

Malignant peripheral nerve sheath tumors are rare sarcomas of the heart. Herein, we report the case of a 24-year-old man who complained of dyspnea, cough, and upper left back pain. He was found to have multiple primary heart tumors obstructing the right superior pulmonary vein in the left atrium, which were diagnosed as malignant peripheral nerve sheath tumors. The patient underwent successful resection of the tumors and immunohistochemistry was utilized for diagnosis.

• Proceedings of the KIPE Conference
• /
• 2005.07a
• /
• pp.439-441
• /
• 2005

A new LLC resonant converter with multiple outputs is proposed for high efficiency and low cost plasma display panel (PDP) power module. In the proposed converter, ZVS turn-on of the primary MOSFETs and ZCS nun-off of the secondary diodes are guaranteed in the overall input voltage and output load range. Moreover, the primary MOSFETs and the secondary diodes have low voltage stresses clamped to input and the output voltage, respectively. Therefore, the proposed converter shows the high efficiency due to the minimized switching and conduction losses. In addition, by employing the transformer, which has the two and more secondary side, the proposed converter can have multiple outputs and they show the great cross-regulation characteristics. As a result, the proposed converter can be implemented with low cost and compact size. The 500W prototype is implemented, which integrates the sustaining and addressing power supplies of PDP power module. The maximum efficiency is 96.8% and the respective output voltages are well regulated. Therefore, the proposed converter is suitable for high efficiency and low cost PDP power module.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.12 no.4
• /
• pp.21-27
• /
• 1975

In this paper, a procedure for deriving of multiple fault detection test sets is presented for fan-out reconvergent combinational logic networks. A fan-out network is decomposed into a set of fan-out free subnetworks by breaking the internal fan-out points, and the minimal detecting test sets for each subnetwork are found separately. And then, the compatible tests amonng each test set are combined maximally into composite tests to generate primary input binary vectors. The technique for generating minimal test experiments which cover all the possible faults is illustrated in detail by examples.

• Journal of Trauma and Injury
• /
• v.36 no.4
• /
• pp.447-450
• /
• 2023

Traumatic abdominal wall hernia is a rare presentation, most commonly reported in the context of motor vehicle accidents and associated with blunt abdominal injuries and handlebar injuries in the pediatric population. A 13-year-old boy presented with multiple traumatic injuries and hemodynamic instability after a high-speed motor vehicle accident. His injuries consisted of massive traumatic abdominal wall hernia (grade 4) with bowel injury and perforation, blunt aortic injury, a Chance fracture, hemopneumothorax, and a humeral shaft fracture. Initial surgical management included partial resection of the terminal ileum, sigmoid colon, and descending colon. Laparostomy was managed with negative pressure wound therapy. The patient underwent skin-only primary closure of the abdominal wall and required multiple returns to theatre for debridement, dressing changes, and repair of other injuries. Various surgical management options for abdominal wall closure were considered. In total, he underwent 36 procedures. The multiple injuries had competing management aims, which required close collaboration between specialist clinicians to form an individualized management plan. The severity and complexity of this injury was of a scale not previously experienced by many clinicians and benefited from intrahospital and interhospital specialist collaboration. The ideal aim of primary surgical repair was not possible in this case of a giant abdominal wall defect.