• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.6
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• pp.1269-1276
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• 2005

In this paper, Mixer using the direct-conversion method intended to use in front-end of a RF receiver is designed. The direct conversion Mixer is an alternative wireless receiver architecture to the well-established superheterodyne, particularly for high integration, low power, and low cost. It operates at 2.4GHz band, and is designed and simulated with a 0.35um CMOS technology and HSPICE simulator. Layout is implemented with a Mentor IC Station. The 2.4GHz CMOS Mixer employs a modified single-balanced Gilbert Cell with additional MOSFET in the output stages to improve IIP2, which is a standard of linearity in direct conversion receiver. Additional coversion-stages's transconductances are controlled by each MOSFET's physical properties. The HSPICE simulation results show that the 2.4GHz CMOS Mixer has voltage gam of 29dB, IIP2 of 63dBm, respectively. The Mixer also draws 3.5mA from a 3.3V supply.

• Journal of Practical Engineering Education
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• v.12 no.1
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• pp.93-100
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• 2020

To qualitative improvement in addition to the quantitative growth of field placement, efforts to reduce short-term (4 weeks) and mid-term professional practice (8 weeks) and to increase the proportion of long-term term professional practice (12 weeks or more) are increasing at university sites. There are the problems: the absence of systematic and specialized field placement curriculum of the short-term and mid-term professional practice, the participation of university field placement increases, companies do not prefer to participate in its program and students hesitate to apply to long-term practice due to their major. In order to solve these problems, this paper proposes the IPBP(Industry Problem Based professional Practice) based on Gyeongbuk K University which the students solve the company's difficulties during the field placement with their professor if need. In order to build a win-win field practice culture with participating companies, we suggest that the IPBP solution field practice presented in this paper is one of the good models.

• Communications of Mathematical Education
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• v.32 no.1
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• pp.1-22
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• 2018

The purpose of the study was to examine the effects of mentoring experience in STEAM classes on pre-service mathematics teachers' teaching competency for STEAM education. The study was conducted with 23 pre-service mathematics teachers who participated in the mentoring program affiliated with free learning semester system during one semester. To investigate the changes of pre-service mathematics teachers' teaching competencies for STEAM education and the effects of the mentoring program, pre, post questionnaires, lesson journals, and whole group discussion data were collected. According to the results, pre-service mathematics teachers' competencies for 'knowledge of STEAM education', 'subject matter knowledge', 'teaching and learning methods', and 'learning environments and circumstances' categories were improved significantly after the mentoring program. Especially, some results indicated that pre-service mathematics teachers' teaching experiences in real STEAM classrooms were very helpful for the development of understandings of STEAM education and construction of practical knowledge.

• Journal of the Korean Society for Library and Information Science
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• v.48 no.1
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• pp.117-147
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• 2014

Mentoring programs have proven highly successful in many industries, and therefore there is an increasing demand for such programs in other fields. Therefore, this study proposed to design and operate an LIS student-librarian mentoring program. To accomplish this, mentees were selected from the LIS students at K University, and mentors were selected by mentees from a pool of LIS workers. The mentoring program was then operated for three months, and all participants were surveyed before and after the program. As a result, first, it was revealed that the librarian mentoring program allowed mentees to enhance their understanding of the practical field, and help them to set career paths and goals. Second, participants insisted that six months is a more appropriate mentoring period, 2-3 hours per meeting is proper as a mentoring time, and considered that the information for mentors and mentees must be provided to each other before mentoring. Third, the intention to rejoin a mentoring program in the future was very high in both groups, but they insisted that the financial support, locational support, and providing sufficient information about mentoring program must be considered.

• Journal of the Korean Society of School Health
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• v.25 no.1
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• pp.133-142
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• 2012

Purpose: The purpose of this study is to identify the effects of suicide reports by mass media and social support on suicide ideation for college students. Methods: Participants are 350 undergraduate students in one university. This study uses three questionnaires: Perception and Attitude toward Suicide Reports, Social Support, and Suicidal Ideation. The SPSS/WIN 12.0 program is used to analyze the data. In particular, the participants' biographical data are analyzed into frequency and percentage. The degrees of suicide reports, social support, and suicide ideation are calculated into Mean and SD. Moreover, the suicide ideation by suicide report and social support are analyzed by the two-way analysis of variance (ANOVA). Results: This study reveals that college students have an average of 30 minutes to one hour news time a day (38.9%) and have at least one suicide report in a month (30.3%). 79.7% participants believe that the suicide report of mass media results in the cause of the copycat suicide. In terms of suicide report and suicide ideation, the types of mass media (F (4,340)=2.41, p<.05) and suicidal urge (F (1,340)=31.23, p<.01), respectively, have significant influences on suicide ideation. On the other hand, the social support and suicide ideation, whether college students have their mentors (F (1,328)=13.26, p<.001) and/or careres (F (1,328)=26.84, p<.001) have significant influences on suicide ideation. Conclusion: College students have higher suicide ideation at news by internet site rather than by radio, TV, and so on. Moreover, college students who have a suicide feeling in the last one year, have more suicide ideation than who have not. On the other hand, college students who have a mentor and carer tend to have less suicide ideation.

• Journal of the Society of Disaster Information
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• v.7 no.4
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• pp.316-327
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• 2011

The purposes of this study are to investigate various experience factors that special guards firstly appointed calculate during the occupational socialization and suggest the preliminary data which is necessary to the establishment of educational service strategy of preliminary special guard and security guard. So, in-depth interviewing and ethnographic study were conducted for 4 special guards firstly appointed. As the result, the occupational socialization process of special guards firstly appointed are quickening period, preparatory period, adaptation period and conflict/maturity period. The first, quickening period is a decision of family background, exercise experience and university entrance. The second, preparatory period is certificates and mentor of department vision, university curriculum and occupational preparation. The third, adaptation period is occupational specialty, occupational professionalism, occupational satisfaction, motivation and company colleagues. The forth, conflict/maturity period is job stress, turnover, conflict in company, efforts for self-development and prospect of job. Therefore, this study will be able to be applied as a guide for special guard's performance improvement and provide educational preliminary data for following-up studies.

• Journal of Periodontal and Implant Science
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• v.39 no.2
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• pp.185-192
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• 2009

Purpose: The aim of this study was to examine the correlation of the subjective and the objective evaluation of edentulous ridge bone quality, and to evaluate the change of the dental implant stability in each bone density group for early healing period after implant installation. Methods: Sixty-seven implants(Osstem implant$^{(R)}$, Seoul, Korea) were included in this study. We evaluated the bone density by 2 methods. The one was the subjective method which was determined by practitioner s tactile sense, the other was the objective bone type was based on Hounsfield units. The implant stability in each bone type group was assessed by resonance frequency analyzer(Osstell mentor$^{(R)}$). Data were analyzed for the change of the implant stability, and they were compared to verify the difference of groups at the time of installation, 2, 6, 10, 14 weeks postoperatively. Spearman's correlation was used to demonstrate the correlation between the subjective and the objective evaluation of the bone density, and analysis of variance(ANOVA) was used to analyze the differences of implant stability at each time point. Results: There was no close relation between the subjective and the objective evaluation of the bone density(r=0.57). In the subjective groups, there was statistically significant difference between the type 1 and 3 at 10 weeks and between the type 2 and 3 at 14 weeks. In the objective groups, there was no statistically significant difference between the D 1, 2, 3, 4, and 5 group with regard to RFA from baseline to 14 weeks(P>0.1). Conclusions: The implant stability increased over time during the study, and it was improved with bone density proportionally after 2weeks postoperatively. It is recommended that the decision of bone density is base on Hounsfield unit for implant loading time.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.04a
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• pp.81-86
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• 2007

The air velocity flowing in inner combustion chamber of Scramjet is supersonic and the time of its stay is very short as a few milliseconds. Within this short time, fuel injection, air-fuel mixing, and combustion process should be accomplished. Several methods are suggested for mixing enhancement. Among these, cavity is selected to study for enhancement of mixing. The numerical simulation is performed in the case of freestream Mach number of 2.5 and cavity located in front of fuel jet injection. 8 different sized cavities of length-height ratio were used in order to recognize the effect about cavity size. Also, the case without cavity was analyzed to find the effect of cavity. Used code compared with the result of experiment under identical conditions and it was verified. Through this comparison and verification, mixing enhancement by cavity could be confirmed.

• Journal of Digital Convergence
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• v.16 no.10
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• pp.69-78
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• 2018

This The purpose of this study is to find policy implications through the analysis of the operational cases and establishment performance of the Leading University for startups. The method of the study was statistical analysis using the data generated during the operation of the Leading University for startups. The results of the study show that there is a difference between short-term performance by gender and age. Second, there was no correlation of the short-term performance with the evaluation, but a negative correlation was observed with the detailed document evaluation part. Third, there is no difference in short-term performance depending on the mentor. Strategic utilization is to reduce the reflection of the founder's short-term performance in the appraisal of the Leading Universities. And there is a need to improve the evaluation method for the applicant. The limitations of this study are that it is inadequate to be an empirical study through statistical analysis. And statistical analysis shows that there are not enough cases. Therefore, I will make an empirical study which will expand the number of cases by including cases of several universities in the future.

• Journal of Korean Academy of Nursing
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• v.37 no.5
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• pp.703-714
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• 2007

Purpose: The purpose of this study was to evaluate the effects of a mentoring program to improve the exercise and dietary habits of adolescents. Methods: A non-equivalent control group, pretest-posttest design was used. The independent variable was a mentoring program for improvement of exercise and dietary habits of adolescents, in which the mentors were nursing students and the mentees were female middle school students. The dependent variables were weekly exercise frequency, weekly exercise time, perception of exercise benefit, frequency of vegetable intake, and dietary habits. The intervention was conducted by various methods such as group education, individual approach through the mentor-mentee relationship, and multimedia approaches. Results: At follow-up, the perception of the exercise benefit was significantly greater in the intervention group than in the control group. The weekly exercise frequency and frequency of vegetable intake in the intervention group were significantly greater after the intervention than those before the intervention. Conclusion: This mentoring program is potentially of an effective health promotion program for adolescents and will enable nursing students who participate in the program as mentors to gain confidence in their professional capability.