• Proceedings of the KIPE Conference
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• 2018.11a
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• pp.161-162
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• 2018

철도챠량에서 일반적으로 사용되는 상용전원은 보조전원장치(이하 SIV)로 불리는 전력변환장치로부터 공급된다. 본 논문에서는 LLC 공진형 컨버터를 적용하여 스위치의 영전압 스위칭(Zero-Voltage-Switching, ZVS)을 통해 높은 효율을 달성하고, 고속스위칭에 의해 인덕터, 커패시터, 트랜스포머와 같은 소자의 부피를 줄이고 시스템의 효율을 높여 기존의 보조전원장치보다 약 40%이상 소형 경량화가 가능한 보조전원장치에 대한 연구를 소개한다.

• Journal of the Korean Society of Radiology
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• v.14 no.2
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• pp.129-138
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• 2020

Due to the nature of the Rosenberg Method, the patient needs to maintain posture for a certain period of time, and the joint space is observed in various forms depending on the angle of knee flexion, which causes difficulties in examination. In order to solve these problems, Image quality was evaluated in order to evaluate the usefulness of the assistive device by making the assistive device itself. SNR and CNR analysis about the presence or absence of an assistive device using the extremity phantom and the angle of the assistive device itself were not statistically significant(p < 0.05). As a result of measuring the distance between the right and left edges of the medial condyle based on the presence or absence of an assist device, and the absence of assist device (96.00±40.6 mm) and presence of an assist device (134.86±17.68 mm) were statistically significant (p <0.05). To find the aLDFA relationship about the femur and tibia, we measured the right and left aLDFA based on the presence or absence of assist device. As a result, the absence of the right-side aLDFA assist device (74.63°±4.87) and the presence of assist device (79.64°±3.65) were statistically significant (p <0.05). The absence of the left-side aLDFA assist device (76.39°±4.62) and the presence of assist device (79.64°±3.65) were statistically significant (p < 0.05). but, As a result of measuring the distance of the overlapping parts of the right and left proximal tibiofibular joint and the lateral condyle, There were no statistically significant differences between the right and left sides. In conclusion, we confirmed that we can obtain Diagnostically valuable images with a constant knee-to-knee spacing using an assist device we self-created. In addition, we could learn through aLDFA relationship between femur and tibial that the smaller the angle, the more medial condyle overlaps with JSW, We also confirmed the significance by deriving similar values on the normal range values of aLDFA using assist devices. However, it is considered necessary to pay attention to internal and external rotations in order to obtain good quality images by evaluating the distance of overlapping parts between proximal tibiofibular joint and lateral condyle.

• Archives of design research
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• v.20 no.3 s.71
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• pp.107-118
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• 2007

The aim of this paper is to suggest a design guideline for a teaching assistant robot by finding out images that satisfy the role of the teaching assistant robot, and to search for a body features that show such images. Role images of teaching assistant robots were established from literature review and factor analysis. And eight elements of body features were extracted from human's elements of body feature. Robot external form samples varied according to the body feature was modeled three-dimensionally. Children, who are the main users of teaching assistant robots, valuated the 3D robot samples projected onto wall in real size. The valuation basis was role images of teaching assistant robots, adjectives about age and gender, preference, and appropriateness as teaching assistant robots. The result of valuation was analyzed by analysis of variance, and analysis of correlation. The result revealed the fact that four elements of body feature (the ratio of head length, height, the ratio of breast girth, and waist girth) were related to role images. Among these elements, height and waist girth was more important than the rest, particularly, waist girth had strong relation with all the role images. Also, in order to reveal tender and kind image, the ratio of head length was proved to have to be adjusted according to waist girth. On the basis of these result, a design guideline for a teaching assistant robot was suggested.

• The Journal of Korean Association of Computer Education
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• v.14 no.1
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• pp.35-43
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• 2011

The purpose of this research is to confirm that how the support type of the assistant teacher changes the students' creativity and self-efficacy in the Robot Education, particularly Robot Edu-Camp. The study objects are 72 elementary students for 8 groups; each group has 9 students, and 4 groups of them have the assistant teachers and others are supported by giving some feedbacks for their questions or some information if they need. The assumption of this study sets up as in the following; there are no differences for the students' creativity and self-efficacy between the supporting of the assistant teachers with making robots and programing together and the giving feedbacks and information if students need. To verify this assumption, we use the nonequivalent control group in the pretest-posttest designs. The result is as in the following. There's no meaningful differences of the students' creativity by the support type of the assistant teachers. But in the self-efficacy, the groups which are giving feedbacks and information if they need have more higher level of achievement than others. The result shows that if the assistant teachers help the students directly, the students' levels of the self-direction, and control are low because they lean on the teachers. This will give you some implications to the follow-up studies about the support type of the assistant teachers in the Robot Education.

• The Korean Journal of Pesticide Science
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• v.10 no.3
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• pp.210-217
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• 2006

The study was carried out to select the effective adjuvant as a photostabilizer for acetamiprid 5% SL(soluble concentrate) and to find its optimum content by using chemical and biological methods. Adjuvants used for the study were KS1 and KS2. Photodegradation test, insecticidal efficacies and residual analysis for the study were investigated. Although photodegradation rate of acetamiprid SL was decreased by addition of KS1 and KS2, the difference between KS1 and KS2 was not significant. As KS2 showed better efficacies against the cotton aphid (Aphis gossypii) and higher amount of residue on pepper than KS1, KS2 was selected as a photostabilizer for acetamiprid SL. Acetamipid SL with KS2 showed lower photodegradation rate, better efficacies against the cotton aphid (Aphis gossypii) and higher amount of residue on pepper as content of KS2 in acetamiprid SL was decreased. Therefore, it was concluded that the optimum content of KS2 was 0.1%. These results have demonstrated that the selected adjuvant could be used to enhance insecticidal activity and reduce spay dose of insecticide by protecting its photodegradation.

• The KIPS Transactions:PartA
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• v.14A no.1 s.105
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• pp.25-30
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• 2007

Korea has deeper digital divide between disabled and non-disabled people than other industrialized countries have. This study attributes the deep divide to policy factors and attempts to discern differences in policies concerning IT assistive devices between Korea and America. This study finds that major differences in policy exist between the two countries, and the differences account for Korea's unsatisfactory state of digital divide. Firstly, Korra has different 'perception' of assistive devices. While IT assistive devices are perceived as rehabilitation tools as well as bridges over digital divide in America, they are still foreign to social welfare and rehabilitation of disabled people in Korea. Secondly, the two countries differ in 'enforcement of policy.' In Korea, unlike in America, compliance with regulations on assistive devises is not compulsory. Besides, laws and regulations do not clarify possible sources of financing and legal sanctions, thus their enforcement is hardly effective. Thirdly, Korea's strategy for assistive device 'market' is very different from America's. America has long-term strategies to enliven the market for IT assistive devices. But Korea provided a lump sum of device development fund, and then gave out the assistive devices free of charge. As a result, the IT assistive device market has not been formed, and the foundation for further device development is yet to be constructed.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.7 no.2
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• pp.133-138
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• 2013

This study was aimed to examine effects of the assistive technology program that has purpose to maintain and promote employment of persons with disabilities. An administrative data constructed by the Korea Employment Agency for the Disabled(KEAD) was utilized. Propensity score matching were used as analysis methods to minish sample selection bias caused by nonrandom sampling. As a result, turnover rate of people with disabilities who used assistive technology device was lower compared to persons with disabilities did not use assistive technology device. Also, in terms of company, for employment promotion effect on the persons with disabilities, company that provided assistive technology device was higher than that of company did not provide assistive technology device. Finally, assistive technology devices were effective in the employment area was confirmed.

• Journal of Digital Convergence
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• v.14 no.10
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• pp.535-542
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• 2016

This study was to explore the meanings and follow-up tasks for enactment of Act on Supply and Utilization Promotion of Assistive Technology Devices for People with Disabilities and Seniors(Assistive Technology Act) in Korea. I conducted analysis about contents and establishment process of the Act. The study found meaningful effects ; it provided the basis for supporting assistive technology devices based on the social model, it led to an Implementation of the national obligations such as UN Convention on the Rights of Persons with Disabilities, it provided terms related to assistive technology. It is suggested to conduct follow-up studies and to put the efforts to strengthen additional laws for backing up the effective policy for extended support of assistive technology devices and for security of budget, for establishing regional service centers, for phasing of professional qualification, for controlling quality, for establishing an information system, and for promoting industries.

• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.5
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• pp.692-699
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• 2008

This paper describes optimal operation method using recognition of walker's will for a robotic walker. Recently, walking aid system has been required according to the increase of elder and handicapped person. However, most of walking aid system don't have actuator for its movement. Unfortunately, standard frames have weakness for the movement to upward/download direction of slope. So, active type walking aids are interested, but it is not easy to control. In this paper, we adapt user's will system that can recognize walking direction and speed. First, FSR(Force Sensing Register) is applied to measure user's will to walk. And then, fuzzy algorithm is used for determining optimal wheel velocity and direction of the walking aid. From the result, walking aid can move smoothly and safely following the user's will. The walking aid can help user to walk more optimally. Here, all the processes are verified experimentally in the real world.

• Journal of the Korean School Mathematics Society
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• v.17 no.1
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• pp.1-21
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• 2014

This research aims to analyze the process of selecting, maintaining, and changing the method of learning mathematics by middle school students from the perspective of self-regulated learning ability, in order to help students to select a rational method of studying. For this purpose, we defined 'assisted-learning' as all kinds of education that education demanders receive to supplement their regular school studies. As results of the research, it was found as follows. First, the students with high self-regulated learning ability selected, maintained, and changed their assisted-learning based on their concrete decision and rational reasons regarding the effect of their learning process and assisted-learning to themselves. Second, the students with high self-regulated learning ability had tendency to be very active participation in class than the students with low ability. Third, the students with high self-regulated learning ability felt the effect of assisted-learning on their learning mathematics, and felt the enhancement of their interest and confidence. Also, it is notable that the students selected 'their own willingness to study' as a major factor for the success of assisted-learning.