• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.4
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• pp.1824-1845
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• 2016

The GMM is a conventional approach which has been recently applied in many face recognition studies. However, the question about how to deal with illumination changes while ensuring high performance is still a challenge, especially with real-world databases. In this paper, we propose a Visual Observation Confidence (VOC) measure for robust face recognition for illumination changes. Our VOC value is a combined confidence value of three measurements: Flatness Measure (FM), Centrality Measure (CM), and Illumination Normality Measure (IM). While FM measures the discrimination ability of one face, IM represents the degree of illumination impact on that face. In addition, we introduce CM as a centrality measure to help FM to reduce some of the errors from unnecessary areas such as the hair, neck or background. The VOC then accompanies the feature vectors in the EM process to estimate the optimal models by modified-GMM training. In the experiments, we introduce a real-world database, called KoFace, besides applying some public databases such as the Yale and the ORL database. The KoFace database is composed of 106 face subjects under diverse illumination effects including shadows and highlights. The results show that our proposed approach gives a higher Face Recognition Rate (FRR) than the GMM baseline for indoor and outdoor datasets in the real-world KoFace database (94% and 85%, respectively) and in ORL, Yale databases (97% and 100% respectively).

• Journal of Korean Neurosurgical Society
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• v.62 no.2
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• pp.256-262
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• 2019

Objective : Pituitary adenomas (PAs) are often detected as incidental findings. However, the natural history remains unclear. The objective of this study was to evaluate the natural history and growth pattern of untreated PAs. Methods : Between 2003 and 2014, 59 PAs were managed with clinico-radiological follow up for longer than 12 months without any kind of therapeutic intervention. Tumor volumes were calculated at initial and last follow-up visit, and tumor growth during the observation period was determined. Data were analyzed according to clinical and imaging characteristics. Results : The mean initial and last tumor volume and diameter were $1.83{\pm}2.97mL$ and $13.77{\pm}6.45mm$, $2.85{\pm}4.47mL$ and $15.75{\pm}8.08mm$, respectively. The mean annual tumor growth rate was $0.33{\pm}0.68mL/year$ during a mean observation period of $46.8{\pm}32.1months$. Sixteen (27%) PAs showed tumor growth. The initial tumor size (HR, 1.140; 95% confidence interval, 1.003-1.295; p=0.045) was the independent predictive factor that determined the tumor growth. Six patients (11%) of 56 conservatively managed non-symptomatic PAs underwent resection for aggravating visual symptoms with mean interval of 34.5 months from diagnosis. By Cox regression analysis, PAs of last longest diameter over 21.75 mm were a significant prognostic factor for eventual treatment. Conclusion : The initial tumor size of PAs was independently associated with the tumor growth. Six patients (11%) of conservatively managed PAs were likely to be treated eventually. PAs of last follow-up longest diameter over 21.75 mm were a significant prognostic factor for treatment. Further studies with a large series are required to determine treatment strategy.

• Journal of Trauma and Injury
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• v.27 no.4
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• pp.139-144
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• 2014

Purpose: Detection and determination of tendon injury in the finger or hand is not easy. Therefore, we aimed to study and evaluate the accuracy and the effectiveness of ultrasonography for the diagnosis of finger tendon injury. Methods: In this study, we enrolled patients, regardless of age and sex, with lacerations on their fingers. Patients with invisible wounds were excluded. We evaluated the accuracy and the effectiveness of ultrasonography and compared the results obtained from ultrasonography and with those obtained by visual observation of the injuries. Results: The sensitivity, the specificity and the accuracy of ultrasonography were found to be 66.7%, 100% and 91.3%, respectively (p<0.001) while those of physical examination were 71.4%, 98.3% and 91.3%, respectively. Small differences were observed between the sensitivities and specificities of the two examinations; however, the accuracies were the same (p<0.001). The area under the receiver operating characteristic (ROC) curve, which was used for diagnosis of tendon rupture using ultrasonography, was found to be 0.985 (95% confidence interval CI: 0.929-0.999),while that of physical examination was 0.938 (95% CI: 0.861-0.980). Conclusion: Ultrasonography can be used an effective diagnostic tool for patients with finger tendon injury.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.4
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• pp.453-461
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• 2019

Intraoperative neurophysiological monitoring (INM) examination identifies the damage caused to the nervous system during surgery. This method is applied in various surgeries to validate the procedure being performed, and proceed with confidence. The assessment is conducted in an operating room, using subdermal needle electrodes to optimize the examination. There are no textbooks or guides for the correct stimuli and recording areas for the surgical laboratory test. This article provides a detailed description of the correct stimuli and recording parts in motor evoked potential (MEP), somatosensory evoked potential (SSEP), brainstem auditory evoked potentials (BAEP) and visual evoked potentials (VEP). Free-running Electromyography (EMG) is an observation of the EMG that occurs in the muscle, wherein the functional state of most cranial nerves and spinal nerve roots is determined. In order to help understand the test, an image depicting the inserting subdermal needle electrodes into each of the muscles, is attached. Furthermore, considering both the patient and the examiner, a safe method is suggested for removal of electrodes after conclusion of the test.