• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.6
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• pp.55-61
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• 2014

This paper related with the ECMA (Enchanced CMA) algorithm performance which is possible to simultaneously compensation of the amplitude and phase by appling the minimum disturbance techniques in the CMA adatpve equalizer. The ECMA can improving the gradient noise amplification problem, stability and roburstness performance by the minimum disturbance technique that is the minimization of the equalizer tap weight variation in the point of squared euclidiean norm and the decision directed mode, and then the now cost function were proposed in order to simultaneouly compensation of amplitude and phase of the received signal with the minimum increment of computational operations. The performance of ECMA algorithm was compared to present MCMA by the computer simulation. For proving the performance, the recovered signal constellation that is the output of equalizer output signal and the residual isi and Maximum Distortion charateristic and MSE learning curve that are presents the convergence performance in the equalizer and the overall frequency transfer function of channel and equalizer were used. As a result of computer simulation, the ECMA has more better compensation capability of amplitude and phase in the recovered constellation, and the convergence time of adaptive equalization has improved compared to the MCMA.

• Korean Journal of Oriental Medicine
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• v.10 no.1
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• pp.49-61
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• 2004

The Standardization of terms in The Pulse studies(脈學) is a need for development of learning. This study, for the correction of existing misused terms in The Pulse studies, we study on modernly and objectively the terms in The Pulse studies. By a focus of ${\ulcorner}$The Pulse Studies of Bin-Ho(瀕湖脈學)${\lrcorner}$, we studies on the new classification of pulse condition. The error of a existing technical books on Pulse studies begin that the classification of pulse condition is not establish a Standardization. For the correction of existing misused terms in The Pulse studies, we study on the pulse condition is expressed objectively a blood vessel that it is a subject of pulse condition. The expression of blood vessel contain a depth of blood vessel, a speed of pulsation, a curve of blood vessel, thickness of blood vessel, a diameter of blood vessel in expand and contract of blood vessel, a interval in expand and contract of blood vessel, a distinctness on a boundary of blood vessel, a speed of blood flow in blood vessel, a volume of blood flow in blood vessel, a condition of blood in blood vessel, a propelling power of blood vessel. These is standard of the new classification of pulse condition.

• Archives of Plastic Surgery
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• v.40 no.4
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• pp.312-319
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• 2013

Over the past decade, driven by advances in educational theory and pressures for efficiency in the clinical environment, there has been a shift in surgical education and training towards enhanced simulation training. Microsurgery is a technical skill with a steep competency learning curve on which the clinical outcome greatly depends. This paper investigates the evidence for educational and training interventions of traditional microsurgical skills courses in order to establish the best evidence practice in education and training and curriculum design. A systematic review of MEDLINE, EMBASE, and PubMed databases was performed to identify randomized control trials looking at educational and training interventions that objectively improved microsurgical skill acquisition, and these were critically appraised using the BestBETs group methodology. The databases search yielded 1,148, 1,460, and 2,277 citations respectively. These were then further limited to randomized controlled trials from which abstract reviews reduced the number to 5 relevant randomised controlled clinical trials. The best evidence supported a laboratory based low fidelity model microsurgical skills curriculum. There was strong evidence that technical skills acquired on low fidelity models transfers to improved performance on higher fidelity human cadaver models and that self directed practice leads to improved technical performance. Although there is significant paucity in the literature to support current microsurgical education and training practices, simulated training on low fidelity models in microsurgery is an effective intervention that leads to acquisition of transferable skills and improved technical performance. Further research to identify educational interventions associated with accelerated skill acquisition is required.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.2
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• pp.81-88
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• 2018

Spectrum sensing, the key technology of the cognitive radio networks, is used by a secondary user to determine the frequency state of a primary user. The energy detection in the spectrum sensing determines the presence or absence of a primary user according to the intensity of the allocated channel signal. Since this technique simply uses the strength of the signal for spectrum sensing, it is difficult to detect the signal of a primary user in the low SNR band. In this paper, we propose a way to combine spectrum sensing and support vector machine using wavelet packet decomposition to overcome performance degradation in low SNR band. In our proposed scheme, the sensing signals were extracted by wavelet packet decomposition and then used as training data and test data for support vector machine. The simulation results of the proposed scheme are compared with the energy detection using the AUC of the ROC curve and the accuracy according to the SNR band. With simulation results, we demonstrate that the proposed scheme show better determining performance than one of energy detection in the low SNR band.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.3
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• pp.63-68
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• 2014

This paper related with the I-CMA (Improved-CMA) algorithm that is possible to compensates of phase in CMA adatpve equalizer which is used for the elemination of intersymbol interference in the multipath fading and band limit characteristics of channel. The new cost function is proposed for the eliminate the amplitude and phase simulataneous by modifying the cost fuction for get the error signal in present CMA algorithm. It has a merit to the algorithm simplicities and eliminats the PLL device for phase compensation after equalization. For proving this, the recovered signal constellation that is the output of equalizer output signal and the residual isi and Maximum Distortion charateristic learning curve that are presents the convergence performance in the equalizer and the overall frequency transfer function of channel and equalizer were used. As a result of computer simulation, the I-CMA has more good compensation capability of amplitude and phas in the recovered constellation. But the convergence time is slow due to the simultaneously phase compensation.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.3
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• pp.57-62
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• 2014

This paper proposes the improving the equalization performance using the adaptive modulus concept to the MCMA blind equalizer in order to the reduction of intersymbol interference which occurs in the band limited and time dispersive communication channel. In MCMA blind algorithm, it is possible to reducing the amplitude and phase rotation of intersymbol interference without training sequence, the fixed constant modulus of transmission signal is used. But in proposed algorithm, the modulus are adaptively varies according to the equalizer output signal, then the improved equalization performance were obtained by the computer simulation. For this, the recovered signal constellation that is the output of the equalizer, the convergence performance by MSE, MD (maximum distortion) and residual isi characteristic learning curve were used. The propose algorithm has fairly good performance compared to the traditional MCMA algorithm in the same adaptive equalization algorithm.

• Archives of Plastic Surgery
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• v.33 no.4
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• pp.454-457
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• 2006

Purpose: The anastomosis of hepatic artery to recipient vessel has a major role in a liver transplantation, so its occlusion is the most important cause of failure of liver transplantations. We made the study to reveal the peculiarities in pediatric liver transplantations compared with adult cases. Methods: From January 1999 to September 2005, we performed 99 cases of pediatric liver transplantation. The mean age at operation was 4.17 years of age. The hepatic vein and portal vein are anastomosed by the general surgeons and then the hepatic artery is anastomosed by the plastic surgeons. The Doppler ultrasonography and computed tomography were used for postoperative checkup for hepatic artery patency. Results: There were no immediate complications, but hepatic arterial occlusion was developed in 3 cases (2.8%). In pediatric patients, the anastomosis of hepatic artery is more difficult than adults because of the rapid respiratory and pulse rate, the small vascular diameter, and the large gap of diameter difference between the recipient and the donor vessels. Conclusion: We could confirm that pediatric liver transplantations are relatively safe but long learning curve was needed.

• Journal of Korean Neurosurgical Society
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• v.29 no.12
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• pp.1577-1583
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• 2000

Objectives : Among the various types of minimally invasive spine surgeries, thoracoscopic surgery is becoming more widely accepted and increasingly utilized. This report delineates our clinical experience using thoracoscopy to resect herniated thoracic discs in 16 patients who suffered from myelopathy or intolerable radiculopathy. Patients and Methods : Between Mar. 1997 and Sep. 1999, 16 consecutive patients underwent thoracoscopic discectomy for treatment of herniated thoracic discs. There were 12 men and 4 women(mean age 43.5 years ; range 18-61 years). Eleven patients presented with myelopathic signs and symptoms from spinal cord compression and 5 patients had incapacitating thoracic radicular pain without myelopathy. The surgical level was varied between T3 and T12. The pathology of specimen were 11 hard discs and 5 soft discs herniations. Thoracoscopic techniques were performed with long narrow spine instruments and high speed drill through 3 or 4 ports under one lung ventilated general anesthesia. During the operation three patients were converted to open thoracotomy due to intolerable one lung ventilation, excessive bleeding and inadequate operation field. The mean operation time was 264min.(range : 100-420min.), and postoperative mean admission period was 11 days. Results : Clinical and neurological outcomes were good in all patients(mean follow-up period 20 months). Among the eleven myelopathic patients, 8 improved neurologically, and 3 stabilized. Among the five radiculopathic patients, 4 recovered completely and no patient had worsened. Postoperative complications were pleural effusion in one case, intercostal neuralgia in one, delayed hemopneumothorax in one, prolonged air leakage in one and pneumonia in one case. Conclusions : Thoracoscopic discectomy needs a steep learning curve to be familiar to anatomical space and handling of endoscopic instruments. However, it is technically feasible and can be effectively performed with acceptable results.

• Clinics in Shoulder and Elbow
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• v.1 no.2
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• pp.160-166
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• 1998

The purpose of this study was to assess the results of arthroscopic subacromial decompression in patients with chronic impingement and to evaluate the results according to the rotator cuff pathology. We evaluated the clinical results of treatment for chronic impingement syndrome in 28 patients from Feb 1996 to Feb 1997. There were twenty men and eight women in age from 24 to 72 years (mean age 51) with dominant arm involvement in sixteen patients. Follow up evaluations averaged 15(range 12-24)months. The average duration of symptoms were 15(range 6­60)months. The final diagnoses which were based on the physical examination, plain radiographs and arthroscopic findings, were stage II impingement in 16 patients and stage ill impingement in 12 patients. We excluded the patients with acromioclavicular arthritis or glenohumeral instability in this study. All patients were managed non-operatively a minimum of six months. During the operation we performed contouring and smoothing the acromial undersurface and only resecting of the anterolateral band of the coracoacromial ligament. The clinical results were quantitated using UCLA shoulder rating score. Satisfactory results were obtained in 23(80%) patients. Unsatisfactory results were obtained in 5(18%) patients with posterior cuff tear. The average UCLA pain score showed significant improvement from 2.8(constant pain) to 7.2(present during heavy activities) at final follow up. The function and active forward flexion scores also increased from their preoperative value. There was no significant differences according to the surface and severity of tear and NeeI' stage (P>0.05). These results compared favorably with those reported following open acromioplasty. While arthroscopic subacromial decompression is a demanding technique with a learning curve, it is a reliable treatment for chronic impingement syndrome. A less aggressive approach to subacromial decompression and preserving the posteromedial band of the coracoacromialligament does not appear to compromise results.

• Journal of Educational Research in Mathematics
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• v.24 no.2
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• pp.125-143
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• 2014

In this study, we analyzed a mathematical discussion in the Calculus II course of the Gifted Science Academy and individual interviews to determine the relationship between cognitive conflicts and commognitive conflicts. The mathematical discussion began with a question from a student who seemed to have a cognitive conflict about the osculating plane of a space curve. The results indicated that the commognitive conflicts were resolved by ritualizing and using the socially constructed knowledge, but cognitive conflicts were not resolved. Furthermore, we found that the cause of the cognitive conflict resulted from the student's imperfect analogical reasoning and the reflective discourse about it could be a learning opportunity for overcoming the conflict. These findings imply that cognitive conflicts can trigger the appearance of commognitive conflicts, but the elimination of commognitive conflicts does not imply that cognitive conflicts are resolved.