• Magazine of the Korean Society of Agricultural Engineers
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• v.17 no.4
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• pp.3897-3920
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• 1975

Since the most of Korean dairy and cattle raising farms are too small to introduce western mechanized farming, it is necessary to develope small size equipments. This study has been carried to develop a rotary mower as on attachment of 8 to 10 horse powertiller which is widely spread in rural area. It will not ony be helpfull for the farmers to harvesting hay grass but also desirable to increase the power tiller utility. The protto type rotary mower designed through the fundamental investigations, has been modified and improved through the field trials, and a series of field tests has been carried to investigate its performance and economic feasibility comparing with existing vailable harvesting equipments. The results are as follows; 1. To increase the stability, two guide wheels are attached to both side of the protto type rotary mower. 2. To prevent the clinging of tall grasses, the vertical driving shafts are covered with cylindrical protectors. 3. The cutting height is adjustable in 8 steps from 2.5 to 20 centimeters by changing the length of guide wheel legs. 4. The practical Critical cutting speed were always higher than theoretical value in both case of single cutting blade and three when the cutting depth was 25 millimeter. 5. The peripheral speed of cutting blade was varied in response to the change of engine speed, mean while the peripheral speed was adequate as it was changhed from 25 to 35 meter per second when the power tiller is operated in proper working ground speed. 6. The time requirement to harvest 10 a were 88.7, 54.6 and 41.4 minutes for the first, second and third stage of ground speed respectively, and because of the difficulty of delivery, it was observed that operating with fourth stage of ground speed was not recomanendable when the grass height is taller than 90 centimeters. 7. The performance of rotary mower were 1.1-1.7, 1.4-4.0, 3.8-11.8 and 7.4-22.0 times of reciprocating mower, portable disc type cutter, hay scythe and ordinary sickle respectively. 8. When the slope exceeds, 20 degree the downward harvesting operation was impossible because of the excessive front end weight, while less than 5 degree of land slope did not effect in field operation. 9. Increased traveling spee caused higher cutting height and slight cutting failure, but seems not to effect to the gross yield, and the efficiency of cutting width were from 83 to 94 precent. 10. Tn rank of economy were rotary mower (3,2 stage operation), reciprocating mower, hay scythe, portable disc type cutter and sickle in order when the annul operation exdeeds 100 hours. From the above results, it is convinced that the protto type rotary mower is good enough to the livestock farmers as a hay harvesting equipment because of its economy, hardiness in operating and its out standing performance and hopefully it will contribute to the extension of Korean livestock farming.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.3923-3930
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• 2014

In this study, the physical and dynamic characteristics of soil were analyzed by selecting 3 sections as research subjects among road and structure construction sections in the construction site of the Gwangyang ${\bigcirc}{\bigcirc}$ industry area, and conducted consolidation analysis and bearing capacity assessments through Midas-GTS according to the construction conditions of the structures and section conditions of reinforcement using stabilized soil. The effects of improving the settlement and bearing capacity according to the improved effects of the stability and sections of reinforcement using stabilized soil in applying the reinforcement method using stabilized soil were analyzed as a solution for improving the settlement and bearing capacity of soft clay for constructing roads and structures. The improvement effects of the settlement and bearing capacity were outstanding when the reinforcement method using stabilized soil to the soft clay was applied. After applying the reinforcement method using stabilized soil, the holdback effect of the consolidation settlement was excellent by decreasing the volume of the consolidation settlement from a minimum of 53% to a maximum of 82%. When the width of the reinforcement using stabilized soil was twice the width of the constructed structure, it was found that the holdback effect of the consolidation settlement ranged from 1% to 7% through the width of reinforcement using stabilized soil. In addition, when applying reinforcement more than 6m in width and 1m in depth using stabilized soil, it was found that the increase in the allowable bearing capacity was 2.3 to 3.3 times more than that before applying the reinforcement, which suggests that the increase in bearing capacity by applying the reinforcement method using stabilized soil was significant.

• The Journal of the Korea Contents Association
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• v.15 no.11
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• pp.635-657
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• 2015

The current society characterized by knowledge-based information technology and multiculturalism put more emphasis on problem-solving skills, creative thinking, and communication skills than any other periods did. In response to the demand of the current times, multidisciplinary, or convergence courses and majors are being created and conducted in college education, yet, with the lack of specific teaching and learning model for the convergence courses. In this context, this study aimed to examine PBL as an instructional model for the convergent approaches in classroom, since PBL has been regarded as a model for fostering the 21st century learning capabilities for student coupled with the learning principles of authentic tasks, learner-centeredness, collaborative learning. This study, after conducted a PBL course for the general art education during the summer semester of 2014, analyzed the result using data collected from students' reflective journals, in-depth interviews, and SNS posts among the students. The result presented students' enhanced self-respect, increased interest in their learning and communication skills, and their recognition of the value on diversity and empathetic attitudes toward each others. In conclusion, PBL showed its potential as an alternative instructional model for the multidisciplinary and convergent learning in college education.

• Journal of Korea Technology Innovation Society
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• v.18 no.1
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• pp.28-48
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• 2015

This study is public R & D institutions report to verify what the impact factors on the course of progress of industrialization based on technology companies who previously received prior to the developed technology, what policies and plans for the next requirements based on this by offering the implications for business rate was to contribute to the improvement of the public research institution technology transfer. In this study, the influence factors on technology commercialization derived through the analysis of existing and previous studies, the characteristics of the previously received corporate environmental characteristics and previous technologies through a survey of the company received a technology transfer from public research institutions commercialization decisions and contributions, including sales and commercialization of the results were analyzed by logistic regression analysis demonstrated how to have relevance. Analysis, and linkage with high production company has an existing case of IT technology transfer, commercialization of higher technical success rate was higher compatibility. On the other hand, were observed and expected success rate were higher when a rather commercialized technologies independently be earlier than if participating in joint research in the development of the technology, unlike previously, completeness of the prior art did not significantly affect. This study has the following policy implications. Public research institutions have developed technologies are commercialized to figure out what the requirements of the technical aspects of consumer technologies in order to create economic wealth. And for technology commercialization for enough technical competencies to absorb the technology, and that the technology and considering the link between business and technology commercialization success to be applied. This study has some limitations. First, the sample size was not sufficient. In relation to the presence and participation of corporate success and commercialization of the R & D process, with many previous studies are needed more in-depth analysis by leading research in the sense that different results are obtained. Also did not reflect the will or the corporate culture, management and organizational skills and belongs to the external environment and internal corporate enterprises industry characteristics affecting the success of corporate management of the business. And lacked sufficient consideration of the various technical characteristics present in the form of joint research and industry. Finally, there is a limit of generalizations about other industries.

• Journal of Korea Technology Innovation Society
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• v.15 no.3
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• pp.675-699
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• 2012

Recently innovation cluster has been emphasized as a valid policy measure for innovation. For suggesting a new model of innovation cluster, we conducted literature review for the theories of regional innovation system(RIS) and innovation clusters. As a result, the success factors of innovation cluster were classified into system measures, physical measures, and social(human resources) measures from the perspective of RIS. The case of Gyeonggi province's innovation cluster policy was examined for an empirical analysis. For an in-depth analysis, a survey for the tenant companies in Pangyo technovalley(PTV) was conducted. As a result, it was found that Gyeonggi province's innovation cluster policy is evolving from 'a government-initiated system' to 'the 3rd-generation convergence RIS' and that PTV is closely related to the system measures of 'support for up-to-date management and technology information' and 'support for academic-research-industry cooperative research and technological cooperation,' physical measures of 'strengthening the function of PTV support division' and 'shared research equipment and other infrastructures,' and social measures of 'legal, financial, and administrative support system' and 'public childcare facilities'. Also, technology sector was divided into IT and non-IT for a validity check to find out that there was no significant difference in all factors, except for the public relations factors. This study is expected to provide resources for other related researches.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.551-561
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• 2017

This study attempts to determine the strategy to improve the quality of staff supervision by exploring the experiences of the staff supervision in community welfare centers. For this purpose, multiple case study was performed by conducting in-depth interviews with 10 supervisors for the analysis data and analyzing the resulting themes. The key subjects from their experience were 'Supervisors recognize and prepare the supervision as Challenge and Aspiration', 'Supervision leaves only chaos and frustration', and 'Inspiration from the supervisor and infinite effort result in fruit'. Based on these results, this study suggests the following practical suggestions for the educational, administrative and supportive functions of Supervision. First, educational functions should be proposed as an extension of supervisor's education opportunities and manuals related to educational growth of supervision. Second, the administrative function should be changed to evaluate social welfare institution's evaluation framework so as to evaluate the supervision internal regulation and supervision according to it and various supervision models should be developed. Third, supportive supervision function that can be encouraged for supervisees should be enhanced. This study was meaningful because it presents specific suggestions for supervisors and supervisee's relation and situation in the community welfare center through the qualitative research method.

• Journal of Korean Society on Water Environment
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• v.32 no.3
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• pp.243-252
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• 2016

In cases of water pollution accidents, accurate prediction for arrival time and concentration of contaminants in a river is essential to take proper measures and minimize their impact on downstream water intake facilities. It is critical to fully understand the behavior characteristics of contaminants on river surface, especially in case of oil spill accidents. Therefore, in this study, the effects of main parameters of advection and diffusion of contaminants were analyzed and validated by comparing the results of Lagrangian particle tracking (LPT) simulation of Environmental Fluid Dynamic Code (EFDC) model with those of Global Position System (GPS)-equipped drifter experiment. Prevention scenario modeling was accomplished by taking cases of movable weir operation into account. The simulated water level and flow velocity fluctuations agreed well with observations. There was no significant difference in the speed of surface particle movement between 5 and 10 layer modeling. Therefore, 5 layer modeling could be chosen to reduce computational time. It was found that full three dimensional modeling simulated wind effects on surface particle movements more sensitively than depth-averaged two dimensional modeling. The diffusion range of particles was linearly proportional to horizontal diffusivity by sensitivity analysis. Horizontal diffusivity estimated from the results of GPS-equipped drifter experiment was 0.096 m²/sec, which was considered to be valid for applying the LPT module in this area. Finally, the scenario analysis results showed that particle movements could be stagnant when discharge from the upstream weir was reduced, implying the possibility of securing time for mitigation actions such as oil boom installation and wiping oil contaminants. The outcomes of this study can help improve the prediction accuracy of particle tracking simulation to establish the most suitable mitigation plan considering the combination of movable weir operation.

• Journal of Technology Innovation
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• v.18 no.2
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• pp.253-288
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• 2010

Production innovation capabilities are critical to the survival and growth of firms. This paper investigates industrial dynamics and dynamic capabilities of firms by looking at how an industry evolution process influences firms' product innovation strategy and how dynamic capabilities affect firms' product innovation process. Korea Wireless Internet industry shows a full cycle of industry evolution process including introduction phase, growth phase, maturity phase, and decline phase using by dynamic technological and market changes. 7 listed companies in Korea Wireless Internet industry were selected. We have conducted multiple case studies based upon in depth interviews. Empirical results show that different phases of industry evolution influence firms' strategy of product innovation. Dynamic capabilities are also appears to be very important to the survival and growth of a firm.

• Journal of Korean Medicine Rehabilitation
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• v.24 no.4
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• pp.41-48
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• 2014

Objectives The present study examines the domestic trend of Failed Back Surgery Syndrome (FBSS) in Korea. Methods The studies on FBSS were investigated via searching Korean web databases. As a result, 41 research papers were found and they were analyzed according to the year of publishment, the titles of journals which have the papers, the types of study, the definition of FBSS, employed treatment trials, and the instruments for assessment. Results The number of the research papers on FBSS published was increased since 2005. The studies on FBSS were mainly published in the Korean Journal of Pain. The most popular type of the studies were the case report and the most studies defined FBSS as persistent or recurring low back pain with or without sciatica after receiving spine surgeries. Various surgical and conservative treatments were employed in the studies and Visual Analogue Scale (VAS), Numeric Rating Scale (NRS), Oswestry Disability Index (ODI) were used as primary means of assessments. Conclusions Reviewing the domestic trends of studies on FBSS and examining the definition of FBSS is essential for the future studies because there is no clear criteria for making diagnosis of FBSS. Therefore, the further studies on FBSS need to be more elaborate with the definition of FBSS, and it is also necessary to apply more assessment tools for the better understanding of FBSS from various aspects. Ultimately, this review is anticipated to benefit the future in-depth study on FBSS.

• Journal of dental hygiene science
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• v.14 no.2
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• pp.107-113
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• 2014

This study was conducted to evaluate the association between periodontal disease and diabetes mellitus. The final analysis population of this study was composed of 4,830 adults with diabetes mellitus or periodontal disease and aged 19 years or older, based on the third-edition data of the 4th Korea National Health and Nutrition Examination Survey (KNHANES) (in 2009). Diabetic status and potential confounders were used in questionnaire materials and physical examination materials, and the presence of periodontal disease was used in the materials for oral health examination by a dentist. For diabetic status, fasting plasma glucose (FPG) levels <100 mg/dl were subcategorized into normal group and FPG levels ${\geq}100mg/dl$ into impaired fasting glucose group; glycosylated hemoglobin (HbA1c) levels <7% into normal group and HbA1c ${\geq}7%$ into diabetes group, on the basis of the American Diabetes Association. According to the 2009 Korea Health Statistics, the case where the pocket depth is 3 mm or more was defined as periodontal disease. The association between the two diseases was evaluated through $x^2$-test and logistic regression analysis using R-commander 2.14. In impaired fasting glucose group, community periodontal index (CPI) groups 3 to 4 had higher risks for periodontal disease 1.23 times (95% confidence interval, 1.07~1.42) than those of CPI groups CPI 0~2, even after adjustment for several confounders. In addition, periodontal disease and diabetes mellitus showed statistically significant differences depending on age, sex, income level, educational background, smoking status, alcohol consumption, and snack intake. The analyses of the third-edition data of the 4th KNHANES showed that there was a statistically significant association between periodontal disease and diabetes mellitus as examined by means of CPI in this study.