• Journal of Engineering Education Research
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• v.12 no.3
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• pp.50-58
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• 2009

A survey was conducted and analyzed for strengthening the employment competitiveness of engineering students. Questionnaires were conducted to students and graduates majoring in mechanical, civil engineering and computer science as well as to small and medium sized industries. It includes the level of satisfaction and requirement to recognize the situation of the students in metropolitan Seoul area. Survey results indicate that for undergraduates and graduates, knowledge of their own majors is most important. However, for industry, the most important factor is the ability of analysis and application, and their personalities. With the results of this survey, it is expected that these discrepancies between industries and students are reduced and the competitiveness of students is strengthened.

• Clinics in Shoulder and Elbow
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• v.12 no.1
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• pp.94-97
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• 2009

Purpose: Hibernoma is a very rare benign soft tissue tumor of the hypervascularized brown fat tissue with no malignant potential. Materials and Methods: However, it is difficult to differentiate a hibernoma from other malignant tumors, such as liposarcoma using computed tomography and magnetic resonance imaging, and a surgical resection with histological confirmation is the treatment of choice. Results: Histopathologically, hibernoma is composed of brown adipose cells that are polygonal and multivacuolated with a centrally located nucleus and granular cytoplasm, unlike white adipose cells. Conclusion: This article describes a patient with a histologically-confirmed hibernoma of the right shoulder.

• Land and Housing Review
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• v.3 no.2
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• pp.187-193
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• 2012

A technology that newly attract attention in the area of energy-related study is the energy harvesting(or scavenging) technology. In this paper, the performance of power generation for the energy harvesting block with a combination of piezoelectric technology and electromagnetic technology among various energy harvesting technologies was investigated. The goal of this study is to evaluate on the applicability of our developed energy harvesting block into the field of urban & housing. First, we evaluated the performance of power generation for the multi-layer energy harvester at laboratory scale. Second, we described the features of our developed prototype module that includes amplification technologies to improve power density per module and evaluated the performance of power generation for the energy harvesting block in a variety of ways. From the test results, the developed product increased the performance of power generation up to 255% or 505% compared to the existing product and its superiority were shown. Finally, we suggested the direction for the improvement of the energy harvesting block module.

• Journal of the Korean Society for Nondestructive Testing
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• v.32 no.5
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• pp.585-596
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• 2012

PVDF(poly vinylidene fluoride) and P(VDF-TrFE)(poly vinylidene fluoride-tetrafluoroethylene) are the typical piezoelectric polymers with unique properties. Even they are inferior to conventional piezoelectric ceramics PZT in electromechanical conversion efficiency and interior loss, though they are superior in receiving sensitivity and frequency bandwidth. Their acoustic impedances are relatively close to water or biological tissue and it is easier to make thin film than other piezoelectric materials. Futhermore, the film is so flexible that it is easy to attach on a complex surface. Those properties are suitable for the ultrasound transducers which are useful for medical and biological application, so that various types of polymer transducers have been developed. In this paper, several important considerations for design and fabrication of piezoelectric polymer transducers were described and their effect on the transducer performance were demonstrated through the KLM model analysis. Then, it was briefly reviewed about the structures of the polymer transducers developed for obtaining images as well as the characteristics of the images in several important medical and biological application fields.

• Fire Science and Engineering
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• v.26 no.4
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• pp.70-76
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• 2012

This paper deal with vehicle fire caused by damage of diesel particulate filter (DPF) on diesel passenger vehicles. In order to reduce particulate matters included exhaust gases, a DPF in the exhaust system were installed diesel vehicles. A DPF was broken by excessively trapped particulate matters, regeneration error with a malfunction of ECU and defect of suction system such as swirl valve. If the DPF was broken, hot exhaust gases was released to the bottom of vehicle and released hot exhaust gases lead to occur the fire through combustible materials around the exhaust system. When a fire happened in the diesel vehicle caused by damage of DPF, silicate inorganic compounds were attached to the exhaust ventilation pipe and muffler. The silicate inorganic compounds were created by DPF combustion consisting of raw material ceramics. If the silicate inorganic compounds attached to the tail pipe in the diesel passenger vehicles, its fire cause will be assumed damage of DPF.

• Allergy, Asthma & Respiratory Disease
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• v.6 no.6
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• pp.315-321
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• 2018

Purpose: Radiocontrast media are widely used in medical imaging to improve diagnostic accuracy. However, studies on the adverse reactions of radiocontrast media in children are limited. We aimed to describe the characteristics of adverse reactions to radiocontrast media among children who had a computed tomography scan or magnetic resonance imaging in a tertiary university hospital. Methods: We retrospectively collected data on adverse reactions to radiocontrast media by the reporting system of a tertiary university hospital. We selected data from children under the age of 19 from July 2011 to December 2017 and analyzed their characteristics. We focused mainly on the characteristics of the index case which is defined by the first adverse event of each subject. Results: During the period, a total of 88,050 radiocontrast media-enhanced imaging studies were performed and 184 cases of adverse reactions were reported. A total of 71 were identified as index cases. Forty-nine (69.0%) were male and the mean age was $12.7{\pm}3.2$ years. The incidence of radiocontrast media-related adverse reactions was 0.09% and severe reactions were 0.002%. The most common clinical feature was skin manifestations (54.9%), followed by gastrointestinal symptoms (40.8%) and neuropsychiatric symptoms (7.4%). Conclusion: Adverse reactions to radiocontrast media rarely occur in children and the incidence of severe reactions is low. Most reactions are mild and are related to the skin and gastrointestinal system. This report would provide good evidence for establishing a management strategy in children scheduled for imaging studies using radiocontrast media.

• Journal of Convergence for Information Technology
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• v.11 no.7
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• pp.104-110
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• 2021

A novel selective oxidation process has been developed for low source/drain (S/D) series resistance of the fin channel metal oxide semiconductor field effect transistor (MOSFET). Using this technique, the selective oxidation fin-channel MOSFET (SoxFET) has the gate-all-around structure and gradually enhanced S/D extension regions. The SoxFET demonstrated over 70% reduction in S/D series resistance compared to the control device. Moreover, it was found that the SoxFET behaved better in performance, not only a higher drive current but also higher transconductances with suppressing subthreshold swing and drain induced barrier lowering (DIBL) characteristics, than the control device. The saturation current, threshold voltage, peak linear transconductance, peak saturation transconductance, subthreshold swing, and DIBL for the fabricated SoxFET are 305 ㎂/㎛, 0.33 V, 13.5 𝜇S, 76.4 𝜇S, 78 mV/dec, and 62 mV/V, respectively.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.2
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• pp.153-160
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• 2019

Electro-mechanical actuator system for aircraft has advantages in compactness and its lightweight, compared to the hydraulic actuator system. Hinge line actuator has low air resistance and is suitable for special purpose such as stealth. This paper describes design contents of 10,000 lbf-in class dual redundant hinge line electro-mechanical actuator system for performance test. The control structure was designed to minimize impact of torque fighting. A mathematical model is proposed to analyze and validate the performances of actuator by comparison with experiment results.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.5
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• pp.533-539
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• 2019

This study proposes a malware classification model that can handle arbitrary length input data using the Microsoft Malware Classification Challenge dataset. We are based on imaging existing data from malware. The proposed model generates a lot of images when malware data is large, and generates a small image of small data. The generated image is learned as time series data by Dynamic RNN. The output value of the RNN is classified into malware by using only the highest weighted output by applying the Attention technique, and learning the RNN output value by Residual CNN again. Experiments on the proposed model showed a Micro-average F1 score of 92% in the validation data set. Experimental results show that the performance of a model capable of learning and classifying arbitrary length data can be verified without special feature extraction and dimension reduction.

• KIPS Transactions on Computer and Communication Systems
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• v.8 no.4
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• pp.87-92
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• 2019

This paper describes the pattern analysis for data of the factory energy consumption by using machine learning method. While usual statistical methods or approaches require specific equations to represent the physical characteristics of the plant, machine learning based approach uses historical data and calculate the result effectively. Although rule-based approach calculates energy usage with the physical equations, it is hard to identify the exact equations that represent the factory's characteristics and hidden variables affecting the results. Whereas the machine learning approach is relatively useful to find the relations quickly between the data. The factory has several components directly affecting to the electricity consumption which are machines, light, computers and indoor systems like HVAC (heating, ventilation and air conditioning). The energy loads from those components are generated in real-time and these data can be shown in time-series. The various sensors were installed in the factory to construct the database by collecting the energy usage data from the components. After preliminary statistical analysis for data mining, time-series clustering techniques are applied to extract the energy load pattern. This research can attributes to develop Factory Energy Management System (FEMS).