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A Study on Evaluation Development of PBL in a Mongolian University (몽골 대학에서의 PBL 수업 평가 개발 연구)

  • Bayarmaa, Natsagdorj;Lee, Keunsoo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.8
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    • pp.322-328
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    • 2018
  • The purpose of this study is to examine the performance of Problem-Based Learning (PBL) based on Google Classroom(GC). GC is an easy and free online learning that plays an important role in education and training recently. Students become increasingly independent in self-directed learning while sharing ideas and resources, transferring knowledge actively across domains and researching for solutions to the given problem in PBL. Students can check the submission date on the task page and start the task with a single click, and teachers can quickly check if the task is complete, and score it directly from GC. Designed The Evaluation of Problem -Based Learning based on GC in this study. The students read the given materials and identify the purpose of the subjects and selected the learning issues, investigated them. After then they discuss the subjects and make the reports. The students work to study them with research papers, books and internet materials. The research findings showed that PBL based on GC was effective in learning together. Students had positive attitude in their PBL learning environment. This study suggests it is possible that the development of PBL Evaluation on the GC.

Incorporating Time Constraints into a Recommender System for Museum Visitors

  • Kovavisaruch, La-or;Sanpechuda, Taweesak;Chinda, Krisada;Wongsatho, Thitipong;Wisadsud, Sodsai;Chaiwongyen, Anuwat
    • Journal of information and communication convergence engineering
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    • v.18 no.2
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    • pp.123-131
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    • 2020
  • After observing that most tourists plan to complete their visits to multiple cultural heritage sites within one day, we surmised that for many museum visitors, the foremost thought is with regard to the amount of time is to be spent at each location and how they can maximize their enjoyment at a site while still balancing their travel itinerary? Recommendation systems in e-commerce are built on knowledge about the users' previous purchasing history; recommendation systems for museums, on the other hand, do not have an equivalent data source available. Recent solutions have incorporated advanced technologies such as algorithms that rely on social filtering, which builds recommendations from the nearest identified similar user. Our paper proposes a different approach, and involves providing dynamic recommendations that deploy social filtering as well as content-based filtering using term frequency-inverse document frequency. The main challenge is to overcome a cold start, whereby no information is available on new users entering the system, and thus there is no strong background information for generating the recommendation. In these cases, our solution deploys statistical methods to create a recommendation, which can then be used to gather data for future iterations. We are currently running a pilot test at Chao Samphraya national museum and have received positive feedback to date on the implementation.

Vibration Characteristics of a Synchro Clutch Coupling for Steam Turbine (증기터빈용 Synchro Clutch Coupling의 진동 특성)

  • Shim, Eung-Gu;Lee, Tae-Gu;Moon, Seung-Jae;Lee, Jae-Heon
    • Plant Journal
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    • v.4 no.3
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    • pp.66-72
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    • 2008
  • The vibration of steam turbine is caused by Mass unbalance, Shaft misalignment, Oil whip and rubbing etc. But in turbine which is normally operated and maintained, the Mass unbalance component possesses the greatest portion. Our power plant has two steam turbines in capacity of 200 MW and 135 MW respectively and each turbine is supported by 6 journal bearings. However, we had many difficulties because the vibration amplitude of #3 and #4 Bearings was high during the start-up and operation mode change of steam turbine. But, with this study, we completely solved the vibration problem caused by the mass unbalance of #1 steam turbine. Until a recent date, #3 and #4 bearings which support high pressure turbine for #1 steam turbine had shown about $135{\mu}m$ in vibration amplitude (sometimes it increased to $221{\mu}m$ maximum. alarm: 6 mils, trip: 9 mils) at base load. After applying the study, they decreased to about $45{\mu}m$ maximum. It is a result from that we did not change the setting value of bearing alignment and only changed the assembly position of internal parts in Synchro clutch coupling rachet wheel which links between high pressure turbine and low pressure turbine, and increased the internal gap and machining of the Pawl cage surface. In the operation of steam turbine, if the vibration value increases by 1X, we should reduce the vibration of bearing by weight balancing. However, unless the vibration of bearing is declined by the balancing, we will have to disassemble and check the component and find the cause. In this study, we researched the way to lower mass unbalance that is 1X vibration component which has the greatest portion of vibration generated by steam turbine and we got good result by applying the findings of this study.

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A study on Mass Unbalance Vibration Generated from 200MW Steam Turbine Synchro Clutch Coupling (증기터빈용 Synchro Clutch Coupling에서 발생하는 진동에 관한 연구)

  • Shim, Eung-Gu;Kim, Young-Kyun;Moon, Seung-Jae;Lee, Jae-Heon
    • 한국전산유체공학회:학술대회논문집
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    • 2008.03b
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    • pp.232-235
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    • 2008
  • The vibration of steam turbine is caused by Mass Unbalance, Shaft Misalignment, Oil Whip and Rubbing etc. but in turbine which is normally operated and maintained, the Mass Unbalance component possesses the greatest portion. Our power plant has two steam turbines in capacity of 200MW and 135MW respectively and each turbine is supported by 6 journal bearings. However, we had many difficulties because the vibration amplitude of No 3 and 4 Bearings was high during the start-up and operation mode change of steam turbine. But, with this study, we completely solved the vibration problem caused by the mass unbalance of No 1 steam turbine. Until a recent date, No 3 and 4 bearings which support high pressure turbine for No 1 steam turbine had shown about 135${\mu}$m in vibration amplitude (sometimes it increased to 221${\mu}$m maximum. alarm: 6mils, trip: 9mils) at base load. After applying the study, they decreased to about 40${\mu}$m maximum. It is a result from that we did not change the setting value of Bearing Alignment and only changed the assembly position of internal parts in Synchro Clutch Coupling Rachet Wheel which links between high pressure turbine and low pressure turbine, and increased the internal gap and machining of the Pawl stopper surface. In the operation of steam turbine, if the vibration value increases by 1X, we should reduce the vibration of bearing by weight balancing. However, unless the vibration of bearing is declined by the balancing, we will have to disassemble and check the component and find the cause. In this study, We researched the way to lower mass unbalance that is 1X vibration component which has the greatest portion of vibration generated by steam turbine and We got good result by applying the findings of this study.

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Development and Application of Life-Assessment Guidelines for Fossil-Fuel Power Plant Facilities in Korea (한국 화력 발전설비의 수명평가기준 개발 및 활용)

  • Choi, Woo-Sung;Song, Gee-Wook;Kim, Bum-Shin;Hyun, Jung-Seob;Heo, Jae-Sil
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.34 no.9
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    • pp.1265-1272
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    • 2010
  • In view of the frequent start-ups and load changes in the recent past, there is a need for fossil-fuel power plants to be more efficient and reliable for long-term operation. Under high-temperature and high-pressure conditions, severe creep and fatigue damages can occur in major plant facilities, particularly, turbines and boilers. For highly stable operation and better maintenance, various techniques that facilitate a systematic assessment of the service life of critical facilities have been developed. However, to date, in Korea, to evaluate the remaining life of major facilities of fossil power plant, qualitative or semiquantitative analyses are carried out without following any standard guidelines or procedure. In this study, a standard code for assessing the remaining life of major plant facilities is proposed. This code takes into account creep and fatigue damage, which are generally accepted as dominant causes of damage to facilities. KEPIC (Korea Electric Power Industry code) is scheduled to include this guideline in 2010.

A Study for Lecture Evaluation Service in University (대학의 강의평가 서비스에 대한 연구)

  • Lee, Moon-Goo
    • Journal of Service Research and Studies
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    • v.1 no.1
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    • pp.91-101
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    • 2011
  • A lecture evaluation is an important factor to validate student's level and improve a reformation of the college evaluation as well. Therefore, this paper researches into the lecture evaluation to apply a better objective method and a fair assessment of all lectures. These researches are analyzed by each subject, based on the lecture assessment performed in K College. First, if a student absent more than 4 weeks, they cannot be participated in the lecture evaluation. Second, the lecture evaluation date takes place when the next class registrations start. Third, the connection between the number of students and the teaching assessment should be considered. Finally, various types of the teaching assessment tools, including the lecture evaluation method such as multiple choices or writing questions need to be applied. Finally lecture evaluation results must be reflected in the next lesson.

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The Effect of Laser Therapy for Diabetic Ulcer : Systematic Review (당뇨병성 궤양의 레이저치료에 대한 효과 : 체계적 문헌고찰)

  • Kang, Ki-Wan;Kang, Ja-Yeon;Jeong, Min-Jeong;Kim, Hong-Jun;Seo, Hyung-Sik;Jang, In-Soo
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.30 no.4
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    • pp.62-74
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    • 2017
  • Objectives : The purpose of this study is to investigate the effect of laser therapy for diabetic ulcer by using methods of systematic review. Methods : In this review, PubMed, Cochrane library, Web of Science, CNKI, CiNii, J-STAGE, NDSL and OASIS were used as the search engines. The search period is from the start date of the search engine to October 3, 2016. Randomized controlled trials(RCTs) using laser therapy for diabetic ulcer were searched and extracted by two independent researchers. Risk of bias(RoB) of Cochrane was used to assess methodological quality of studies. Results : Finally, five RCTs were selected. The follow-up period ranged from 15 days to 20 weeks. InGaAlP laser, GaAlAs laser and light emitting diode(LED) were used to treat diabetic ulcer. The clinical trials used sham laser irradiation or standard treatment as control in comparison to laser therapy. The endpoints included ulcer size, rate of healing and time to healing with follow-up period. The RCTs demonstrated therapeutic outcomes with no adverse effect. Most items of RoB were unclear and methodological quality was low. Conclusions : Our analysis suggests that laser therapy has therapeutic effects for diabetic ulcer. However, more systematic and stringent clinical trials will be required.

Immediate Effect of Pressure Pain Threshold and Flexibility in Tensor Fascia Latae and Iliotibial Band According to Various Foam Roller Exercise Methods

  • Kim, Ho;Shin, Wonseob
    • Journal of International Academy of Physical Therapy Research
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    • v.10 no.4
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    • pp.1879-1888
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    • 2019
  • Background: The treatment of pain in the iliotibial band friction syndrome has been difficult to determine, according to studies to date. However, recent studies have suggested that flexibility in the subacute stage of pain in the iliotibial band friction syndrome may help reduce pain. Objective: To investigate the immediate effect on pressure pain threshold and flexibility of the tensor fascia latae and iliotibial band by applying static and dynamic myofascial release foam rolling and self-stretching to adults with shortening iliotibial band. Design: Randomized controlled trial Methods: In this study, 50 subjects who were selected in advance as a randomized controlled trial were randomly allocated using a R Studio program. The included subjects were randomly allocated to three intervention groups. The static self-myofascial release 18 people, dynamic self-myofascial release group 16 people separated the self-stretching group 16 people and conducted a homogeneity check in advance. Before the start of the experiment, after of the experiment, 5 minutes after the end of the experiment, the pressure pain threshold and flexibility change for each part were measured. Results: The results of this study showed that the static self-myofascial release showed a significant difference in the pressure pain threshold in the tensor fascia latae and middle, lower part of the iliotibial band, compared with the other intervention groups (p<.05). In change of flexibility, the static self-myofascial release was significantly different than the other intervention groups (p<.05). Conclusion: The result of this study suggest that static self-myofascial release using foam roller may help to improve the pain and flexibility of the iliotibial band and to apply it as a more discerning intervention.

A Case Report on Pain Associated with a Varicocele Treated with Korean Medicine, including Dong's Acupuncture (동씨침을 포함한 한방치료로 호전된 정계정맥류로 인한 통증 치험 1례)

  • Kim, Na-yeon;Yoon, Mi-jung;Choi, Hong-sik;Kim, Seung-mo;Kim, Kyung-soon
    • The Journal of Internal Korean Medicine
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    • v.42 no.5
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    • pp.760-766
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    • 2021
  • Objectives: This study investigated the effectiveness of Dong's acupuncture for pain associated with a varicocele. Methods: A 23-year-old male patient visited for pain due to varicocele that occurred on March 2 and was treated with acupuncture and moxibustion three times on March 16, 17, and 19. The Numerical Rating Scale (NRS) was used to evaluate the patient's pain. Results: After the three treatments, the NRS scores decreased, and the patient's subjective symptoms improved. Also, the patient required no medication for a week from the date of treatment start. Conclusions: These findings demonstrate that Korean medicine may be an option for treating a painful varicocele, but further research is required for confirmation.

Effects of Herbal Medicines on Bone Mineral Density Score in Osteoporosis or Osteopenia: Study Protocol for a Systematic Review and Meta-Analysis (한약이 골다공증 혹은 골감소증 환자의 골밀도에 미치는 영향: 체계적 문헌고찰 및 메타분석을 위한 프로토콜)

  • Hong, Su Min;Lee, Eun Jung
    • Journal of Korean Medicine Rehabilitation
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    • v.31 no.2
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    • pp.49-55
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    • 2021
  • Objectives The impact of social and economic losses on society due to the occurrence of osteoporosis patients is serious. The purpose of this study is to identify the types and effects of herbal medicine for osteoporosis and osteopenia. Methods We will investigate 8 online databases (MEDLINE/PubMed, Cochrane library, EMbase, China National Knowledge Infrastructure [CNKI], J-stage, National Digital Science Library [NDSL], Research Information Sharing Service [RISS], Koreanstudies Information Service System [KISS]) without language, publication date limitation for the clinical study of herbal medicine for osteoporosis and osteopenia published between the start of the database and 2021. The frequency, duration and pattern of the any type of herbal medicine utilization will be analyzed. Results Randomized controlled trials about herbal medicine or herbal medicine extracts for osteoporosis and osteopenia should be included in the study. Cochrane risk in bias tools will be used to evaluate the methodological quality of the study. A risk ratio or mean difference with a 95% confidence interval will show the effects of herbal medicine or herbal medicine extracts for osteoporosis and osteopenia. Conclusions The results of the systematic review will reflect the current status of herbal medicine treatment for osteoporosis and osteopenia, and it can be expected to verify the validity of the effectiveness, and provide it as a basic data for the use of herbal medicine in clinical utilization.