• East Asian mathematical journal
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• v.25 no.3
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• pp.299-320
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• 2009

In mathematics, the education of the geometry proof has been playing an important role in promoting the ability for logical thinking by means of developing the deductive reasoning. However, despite of those importance mentioned above, considering the present condition for the education of the geometry proof in middle schools, it is still found that most of classes are led mainly by teachers, operating the cramming system of eduction, and students in those classes have many difficulties in learning the geometry proof course. Accordingly this thesis suggests the other method that is distinguished from previous proof educations. The thesis of Kai-Lin Yang and Fou-Lai Lin on 'A Model of Reading Comprehension of Geometry Proof (RCGP)', which was published in 2007, have various practical examples based on the model. After composing classes based on those examples and instructing the geometry proof, found out a problem. And then advance a new teaching model that amendment and supplementation However, it is considered to have limitation because subjects were minority and classes were operated by man-to-man method. Hopefully, the method of proof education will be more developed through performing more active researches on this in the nearest future.

• PNF and Movement
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• v.13 no.2
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• pp.111-118
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• 2015

Purpose: The purpose of this study was to describe the effects of proprioceptive neuromuscular facilitation (PNF) on episodes of foot drop and the ability to cross obstacles in stoke patients. Methods: The patient was a 57-year-old man with left hemiplegia. This patient displayed episodes of foot drop while walking and issues with crossing obstacles. The patient underwent therapeutic exercises and occupational therapy twice daily at a hospital five times a week. The patient was treated with PNF outside of these therapeutic sessions. Each session, which was 60 minutes in length, was conducted 3 times a week over 8 weeks. Over the course of treatment, a pre-test and post-test were completed. The patient walked for a test time of 6M. During the testing process, the patient crossed obstacles. In addition, the number of foot drop episodes was recorded. Each test was measured three times to determine the mean value. Results: After the PNF treatments, the number of foot drop episodes decreased from five to one. The 6M walking test time during which the patient crossed obstacles also decreased from 18 seconds to 10 seconds. Conclusion: The use of PNF treatments is beneficial to reduce the number of foot drop episodes while walking and to improve the ability to cross obstacles in stroke patients.

• Journal of Mechanical Science and Technology
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• v.19 no.3
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• pp.792-801
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• 2005

This paper discusses a dc motor equipped electric power steering (EPS) system and demonstrates its advantages over a typical hydraulic power steering (HPS) system. The tire-road interaction torque at the steering tires is calculated using the 2 d.o.f. bicycle model, in other words by using a single-track model, which was verified with the J-turn test of a real vehicle. Because the detail parameters of a steering system are not easily acquired, a simple system is modeled here. In previous EPS systems, the assisting torque for the measured driving torque is developed as a boost curve similar to that of the HPS system. To improve steering stiffness and return-ability of the steering system, a third-order polynomial as a torque map is introduced and modified within the preferred driving torques researched by Bertollini. Using the torque map modification sufficiently improves the EPS system.

• 한국연소학회:학술대회논문집
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• 2005.10a
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• pp.58-63
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• 2005

As fuel cells approach commercialization, hydrogen production becomes a critical step in the overall energy conversion pathway. Reforming is a process that produces a hydrogen-rich gas from hydrocarbon fuels. Hydrogen production via autothermal reforming (ATR) is particularly attractive for applications that demand a quick start-up and response time in a compact size. However, further research is required to optimize the performance of autothermal reformers and accurate models of reactor performance must be developed and validated. The design includes the requirement of accommodating a wide range of experimental set ups. Factors considered in the design of the reformer are capability to use multiple fuels, ability to vary stoichiometry, precise temperature and pressure control, implementation of enhancement methods, capability to implement variable catalyst positions and catalyst arrangement, ability to monitor and change reactant mixing, and proper implementation of data acquisition. A model of the system was first developed in order to calculate flowrates, heating, space velocity, and other important parameters needed to select the hardware that comprises the reformer. Predicted performance will be compared to actual data once the reformer construction is completed. This comparison will quantify the accuracy of the model and should point to areas where further model development is required. The end result will be a research tool that allows engineers to optimize hydrogen production via autothermal reformation.

• Journal of Applied Biological Chemistry
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• v.65 no.1
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• pp.75-79
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• 2022

Antioxidant, α-glucosidase inhibition, and anticoagulant effects of 80% ethanolic extract from mistletoe (Viscum album var. coloratum) were investigated. The yield and polyphenol content of the mistletoe extract were 30.9±0.4% and 57.6±1.5 mg gallic acid equivalents/g, respectively. The antioxidant effects of the mistletoe extract such as free and cationic radical scavenging ability, nitrite scavenging ability, and reducing power increased in proportion to its concentration. Also the mistletoe extract inhibited the activity of α-glucosidase, and delayed plasma coagulation mainly by inhibiting the extrinsic and common pathways in blood coagulation system.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.10a
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• pp.343-346
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• 2009

The grounding system of low voltage power systems is TT grounding system in Korea. In order to follow the international standard, TN grounding system is adopted. However, the performance of grounding systems has not been evaluated. This paper deals with the experimental results of protection ability of grounding system when lightning surge invades to the neutral line of low voltage power system. As a result, the TT grounding system is most frail for the lightning surge and it does not protect the electrical devices. On the other hand, the TN grounding system perfectly protects the electrical equipment and prevents the electric shock for human through the equipotential bonding. In case of TN system with supplement grounding, it is very important to lower the supplement grounding resistance to protect the electrical equipment and electric shock for human.

• Journal of The Korean Dental Society of Anesthesiology
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• v.10 no.1
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• pp.27-33
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• 2010

The gag reflex is a physiologic reaction which safeguards the airway from foreign bodies. But, an exaggerated gag reflex can be a severe limitation to a patient's ability to accept dental care and for a clinician's ability to provide it. The overactive gag reflex can be due to psychological factors or physiological factors, or both. Psychological factors can include fear of loss of control and past traumatic experiences. A 58-year-old man, scheduled for extraction of left upper second molar, left lower second and third molar and implantation of left upper second molar, and left lower second molar had no specific underlying medical problems. He had exaggerated gag reflex. Dental treatment was successfully performed using intravenous sedation. Intravenous sedation with midazolam and propofol was a useful management technique for reflex control during dental treatment extended to the posterior regions in the oral cavity.

• The Korean Journal of Pain
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• v.9 no.1
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• pp.200-205
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• 1996

Radiofrequency thermocoagulation(RF) techniques are safe and effective methods as compared to neurodestructive procedure. Other advantages are: ability to perform RF lesions under local or sedative anesthesia, rapid recovery period, low incidence of morbidity and mortality, ability to repeat RF lesions, and leaves no significant scarring. We performed C2 ganglionotomy by RF lesion generator on a patient, suffering post-traumatic occipital neuralgia, as the patient did not respond to conservative therapies such as: trigger point injection, TENS, cryotherapy and stretch, occipital nerve block, C2 ganglion block. Prognostic nerve block was performed usng local anesthetics. Excellent effect was conformed before C2 ganglionotomy. This procedure was performed under fluoroscopy. Type RCK-2A Rosomoff Cordotomy kit was used to stabilize the head and neck. Postoperatively, the patient was free of occipital pain and head motions no longer triggered pain. To date, the patient remains symptom free except for some cervical discomfort.

• Journal of the Korea Society of Computer and Information
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• v.25 no.8
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• pp.39-45
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• 2020

Despite the increasing interest in cyber security in recent years, the emergence of new technologies has led to a shortage of professional personnel to efficiently perform the cyber security. Although various methods such as cyber rage are being used to cultivate cyber security experts, there are problems of limitation of virtual training system, scenario-based practice content development and operation, unit content-oriented development, and lack of consideration of learner level. In this paper, we develop a fuzzy rule-based user-customized training scenario automatic generation system for improving user's ability to respond to infringement. The proposed system creates and provides scenarios based on advanced persistent threats according to fuzzy rules. Thus, the proposed system can improve the trainee's ability to respond to the bed through the generated scenario.

• Elastomers and Composites
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• v.56 no.2
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• pp.72-78
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• 2021

A phase-change material (PCM) is a material that has the ability to delay heat transfer by absorbing heat from its environment or releasing heat to its environment while its phase changes from solid to liquid or liquid to solid at a specific temperature. As it is applied, it can contribute to environmental conservation such as energy savings and carbon dioxide emission reduction. In order for a PCM to store and release heat, the volume change during its phase transition should be large, and thus a phase transition space is required. When a PCM is used as a polymer additive, it is confined within the polymer, and there is no phase transition space; thus, its ability to absorb and release heat is significantly reduced. Therefore, in this study, porous silica was used to provide EVA/PCM compounds with sufficient space for their phase transition, and to improve the compatibility between the EVA and PCM, modified silica is used: surface-modified 5 wt% silica with 3-methacryloxypropyltrimethoxysilane. The compound was prepared and compared with the silica compound. The presence or absence of the modified silica surface modification was confirmed using Fourier-transform infrared spectroscopy and thermogravimetric analysis, the heat capacity of the compound was evaluated based on a differential scanning calorimetry analysis, and its mechanical strength and morphology were determined using scanning electron microscopy.