• Transactions of the Korean Society of Machine Tool Engineers
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• v.15 no.3
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• pp.73-81
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• 2006

This paper describes our primary study for a new method of recognizing materials, which is need for precision work system. This is a study of dynamic characteristics of smart sensors, new method$(R_{SAI})$ has the sensing ability of distinguishing materials. Experiment and analysis are executed for finding the proper dynamic sensing condition. First, we developed advanced smart sensor. We made smart sensors for experiment. The type of smart sensor is HH type. The smart sensor was developed for recognition of material. Second, we develop new estimation methods that have a sensing ability of distinguish materials. Dynamic characteristics of sensor are evaluated through new recognition index$(R_{SAI})$ that ratio of sensing ability index. Distinguish of object is executed with $R_{SAI}$ method relatively. We can use the $R_{SAI}$ method for finding materials. Applications of this method are finding abnormal condition of object (auto-manufacturing), feeling of object(medical product), robotics, safety diagnosis of structure, etc.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.1
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• pp.48-55
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• 2002

This paper deals with the sensing ability of the smart sensor that has the sensing ability to distinguish materials according to the input condition changing. This is a study of dynamic characteristics of sensor. We have developed a new signal processing method that can distinguish among different materials. The smart sensor was developed for recognition of materials. Experiments and analysis were executed to estimate ability to recognize objects according to the input condition. First, we developed the advanced smart sensor. Second, we developed the new method, which has the capability sensing of different materials. Dynamic characteristics of the smart sensor were evaluated relatively through a new $R_{SAI}$ method. According to frequency changing, influence of the smart sensor are evaluated through a new recognition index ($R_{SAI}$) that ratio of sensing ability index. Applications of this method are for finding abnormal conditions of objects (auto-manufacturing), feeling of objects (medical product), robotics, safely diagnosis of structure, etc.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.4
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• pp.253-263
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• 2021

Concrete structures are damaged by aging and external environmental factors. This type of damage is to appear in the form of cracks, to proceed in the form of spalling. Such concrete damage can act as the main cause of reducing the original design bearing capacity of the structure, and negatively affect the stability of the structure. If such damage continues, it may lead to a safety accident in the future, thus proper repair and reinforcement are required. To this end, an accurate and objective condition inspection of the structure must be performed, and for this inspection, a sensor technology capable of detecting damage area is required. For this reason, we propose a deep learning-based image processing algorithm that can detect spalling. To develop this, 298 spalling images were obtained, of which 253 images were used for training, and the remaining 45 images were used for testing. In addition, an improved loss function and data augmentation technique were applied to improve the detection performance. As a result, the detection performance of concrete spalling showed a mean intersection over union of 80.19%. In conclusion, we developed an algorithm to detect concrete spalling through a deep learning-based image processing technique, with an improved loss function and data augmentation technique. This technology is expected to be utilized for accurate inspection and diagnosis of structures in the future.

• The Journal of the Convergence on Culture Technology
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• v.9 no.4
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• pp.549-555
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• 2023

Jacking force loss management inside the PSC Box girder of a common high-speed railway is a very important feature in girder performance, and requires detailed management during the maintenance of the girder. This study aimed to analyze the timing of re-tension prediction of PSC Box girder based on the reduction level of the packing force inside the girder and the results of the tension loss measured without the train load test. As a result of predicting the timing of re-tension according to the level of tension reduction of the PSC Box Girder, the Jacking Force Loss curve was gently analyzed before the structure reached 17 years after confirmed completion, and 17 years later, it was found that the jacking force loss curve progressed rapidly. The results confirmed that the tension of the structure decreases with the service life increase, but considerably decreases as the structure ages. Therefore, more data and research on tension loss of facilities over 20 years are much required.

• Journal of Genetic Medicine
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• v.6 no.1
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• pp.25-37
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• 2009

Hereditary peripheral neuropathies can be categorized as hereditary motor and sensory neuropathies (HMSN), hereditary motor neuropathies (HMN), and hereditary sensory neuropathies (HSN). HMSN, HMN, and HSN are further subdivided into several subtypes. Here, we review the most recent findings in the molecular diagnosis and therapeutic strategy for hereditary peripheral neuropathies. The products of genes associated with hereditary peripheral neuropathy phenotypes are important for neuronal structure maintenance, axonal transport, nerve signal transduction, and functions related to the cellular integrity. Identifying the molecular basis of hereditary peripheral neuropathy and studying the relevant genes and their functions is important to understand the pathophysiological mechanisms of these neurodegenerative disorders, as well as the processes involved in the normal development and function of the peripheral nervous system. These advances and the better understanding of the pathogenesis of peripheral neuropathies represent a challenge for the diagnoses and managements of hereditary peripheral neuropathy patients in developing future supportive and curative therapies.

• Journal of Oral Medicine and Pain
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• v.19 no.1
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• pp.125-136
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• 1994

Observation of elastic fiber's change of mouse TMJ due to several round factor, principally external stimulations, their influence on the TMJ structure's change and the analize of the consecutive evolution of the disease in most important. So, the author believe that the factor of TMJ feature is the elastic feature's change and it's the principal factor of the TMJ disease. For observation of the increase and disposition of elastic fiber that to regulate the elastic feature of tissue and allow it existence. For this propose, observation with histologic methods on 20mouse ICR of 3 days, 1 week, 2 weeks, 3 weeks and 4 weeks. The results were as follow : 1. In the early stage, the condyle of TMJ is originated from cartilage mass, and it's calcification is endochondral. 2. In the early stage, the disc is relatively thin and immature, but in the later stage the fiber is dense and the disposition is most functional. 3. Observation of the early stage, the elastic fiber is a thin fiber that to across antero- posterior direction, but in the later stage elastic fiber are developed, the disposition that in the early stage was perpendicular to articular surface, now in parallel. 4. The elastic fiber was observated most clearly in the retrodiscal tissue. 5. In conclusion, the elastic fiber is observed like a thin fiber 1 week from born, but the fiber to increase the weight and it dispose functionally, and 4 week from born, it can realize the normal function.

• Korean Journal of Animal Reproduction
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• v.22 no.1
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• pp.67-72
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• 1998

Nowadays many kinds of foreign breed horse and Korean native Cheju horse are raised in Korea. Horse has complicated structure and function to maintain normal health, and to overcome severe condition during gallop at full speed. Sometimes the disease take a bad turn becuase of difficulty of correct diagnosis for horse disease. In recent times, horse farm for fattening and reproduction is gradually increasing. However, thoracic disease and abdominal disease are frequently occuring by defect in raising management. But the diagnosis of these kinds of disease is difficult by former diagnostic method. Ultrasonographic diagnostic method is a method to slove the problem. In abroad, nowadays ultrasonography has been reported for circulatory organs and abdomonal organs in horse, cattle, sheep, and dog, and the importance of ultrasonographic diagnosis is recognized in veterinary clinical medicine. In the country, ultrasonography of Korean native goat, cattle and dog was recently reported, but there was no report for the ultrasonography of horse. So, ultrasonogram for the thyroid glands, jugular vein and carotid artery was evaluated in Cheju horse and Thoroughbred horse. Thyroid gland, jugular vein and carotid artery were determined on both sides of neck. The length of right thyroid lobe at the Thoroughbred horse, Thoroughbred foul, Cheju horse and Cheju foul were 54.8, 45.1, 46.1 and 42.2 mm, respectively. The width of right thyroid lobe at the Thoroughbred horse, Thoroughbred foul, Cheju horse and Cheju foul were 18.1, 14.3, 14.6 and 14.2 mm, respectively. The height of right thyroid lobe at the Thoroughbred horse, Thoroughbred foul, Cheju horse and Cheju foul were 27.3, 25.6, 26.2 and 25.5 mm, respectively. Similar ultrasonographic measurements were obtained for the left thyroid gland. The internal diameter of left jugular vein at the Thoroughbred horse, Thoroughbred foul, Cheju horse and Cheju foul were 10.6, 9.7, 10.5 and 9.2 mm, respectively. Similar ultrasonographic measurements were obtained for the right jugular vein. The internal diameter of right carotid artery at the Thoroughbred horse, Thoroughbred foul, Cheju horse and Cheju foul were 9.5, 8.8, 9.1 and 8.5 mm, respectively. Similar ultrasonographic measurements were obtained for the left carotid artery. It is concluded that the ultrasonographic values of this study provides references for the diagnosis of morphologic changes in the thyroid gland, jugular vein and carotid artery in Korean native Cheju horse and Thoroughbred horse.

• Smart Structures and Systems
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• v.32 no.1
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• pp.61-81
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• 2023

This study presents an ensemble learning based Bayesian model updating approach for structural damage diagnosis. In the developed framework, the structure is initially decomposed into a set of substructures. The autoregressive moving average (ARMAX) model is established first for structural damage localization based structural motion equation. The wavelet packet decomposition is utilized to extract the damage-sensitive node energy in different frequency bands for constructing structural surrogate models. Four methods, including Kriging predictor (KRG), radial basis function neural network (RBFNN), support vector regression (SVR), and multivariate adaptive regression splines (MARS), are selected as candidate structural surrogate models. These models are then resampled by bootstrapping and combined to obtain an ensemble model by probabilistic ensemble. Meanwhile, the maximum entropy principal is adopted to search for new design points for sample space updating, yielding a more robust ensemble model. Through the iterations, a framework of surrogate ensemble learning based model updating with high model construction efficiency and accuracy is proposed. The specificities of the method are discussed and investigated in a case study.

• Journal of Chest Surgery
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• v.20 no.2
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• pp.223-229
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• 1987

Doppler echocardiography provides valuable information regarding prosthetic heart valve function rather than structure. There are three methods of expressing the severity of mitral valve obstruction: the transvalvular pressure gradient, effective valve area, and pressure half-time. Of these, the transvalvular pressure gradient [~p] can be determined by the measurement of maximum transvalvular blood flow velocity [V] according to the modified Bernoulli`s equation [gp=4V*]. Eleven patients, who underwent mitral valve replacement with Duromedics mechanical prostheses, and 17 normal persons were investigated. There were significantly higher calculated pressure gradients in prosthetic than normal mitral valves [9.*10*2.22mmHg-vs-3.26*0.99mmHg:p<0,01], and there was a inverse relationship between pressure gradient and prosthetic valve size [11.17*0.%mmHg in size 27mm and 29mm -v- 7.38*1.12mmHg in size 31mm and 33mm; r=0.85, p<0.01] The noninvasive Doppler technique should be useful in the diagnosis of prosthetic valve obstruction.

• Clinical and Experimental Pediatrics
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• v.64 no.10
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• pp.497-503
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• 2021

Reading disability (dyslexia) refers to an unexpected difficulty with reading for an individual who has the intelligence to be a much better reader. Dyslexia is most commonly caused by a difficulty in phonological processing (the appreciation of the individual sounds of spoken language), which affects the ability of an individual to speak, read, and spell. In this paper, I describe reading disabilities by focusing on their underlying neurobiological mechanisms. Neurobiological studies using functional brain imaging have uncovered the reading pathways, brain regions involved in reading, and neurobiological abnormalities of dyslexia. The reading pathway is in the order of visual analysis, letter recognition, word recognition, meaning (semantics), phonological processing, and speech production. According to functional neuroimaging studies, the important areas of the brain related to reading include the inferior frontal cortex (Broca's area), the midtemporal lobe region, the inferior parieto-temporal area, and the left occipitotemporal region (visual word form area). Interventions for dyslexia can affect reading ability by causing changes in brain function and structure. An accurate diagnosis and timely specialized intervention are important in children with dyslexia. In cases in which national infant development screening tests have been conducted, as in Korea, if language developmental delay and early predictors of dyslexia are detected, careful observation of the progression to dyslexia and early intervention should be made.