• Title/Summary/Keyword: MegaStudy

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Study on Hydration Properties of High Strength Mass Concrete to apply Precast Concrete (PC 적용을 위한 고강도 매스콘크리트의 수화특성에 관한 연구)

  • Park, Heung-Lee;Kim, Sung-Jin;Lee, Hoi-Keun;Lee, Seung-Hoon;Park, Byung-Keun;Jung, Sang-Jin
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.04a
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    • pp.661-664
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    • 2008
  • As architectures have recently become high-risers and megastructured, stable high strength products have been ensured. Accordingly, use of precast concrete accouplement has been increased in order to facilitate air compression and rationalize construction. Since not only external heating but also internal temperature rise caused by the accumulation of cement hydration heat in manufacturing process, precast concrete members with large cross-section used for high-rise mega-structure's columns and beams may exhibit different temperature history compared to the precast concrete members for wall and sub-floor with relatively small cross-sections. Therefore, this study aims to elucidate the characteristics of temperature history of mass concrete members cast with high-strength concrete for precast concrete application. In this study, large cross-sectional precast concrete mock-up, unit cement quantity, and temperature histories in manufacturing precast concrete member under different curing condition were inclusively investigated.

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A study on Value and Application of Mobile Harbor in Terms of Coastal Transportation (모바일하버(Mobile Harbor)의 가치와 활용방안에 대한 연구 - 연안운송 중심으로 -)

  • Shin, Chang-Hoon;Jeong, Su-Hyun;Park, Soo-Nam
    • Journal of Navigation and Port Research
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    • v.34 no.3
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    • pp.221-228
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    • 2010
  • As container traffic is increasing, the introduction of mega-vessel has had a significant impact on the ports and terminals business. This movement of container shipping has led to intensely competitive environment among ports, so substantial pressures to develop new container ports or to expand existing ones, have been grown. However, it requires a huge investment, especially cost and time, to overcome environmental, geographical and financial restrictions generated from developing a port. This study addressed the Mobile Harbor, the new concept of marine logistics system as an alternative strategy. We performed an economic analysis on the introduction of the Mobile Harbor in coastal transport sector and also a sensitivity analysis to examine the effects of changing factors related on the economic evaluation. We have examined the value and application of Mobile Harbor as a preliminary study, which may contribute to further studies on the Mobile Harbor.

A Study on the Promotional Media Strategy of Non-face-to-face and Martial Arts Events

  • Kim, Bo-kyung
    • Journal of the Korea Society of Computer and Information
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    • v.25 no.12
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    • pp.271-278
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    • 2020
  • This study looked at the World Martial Arts Mastership's 'non-face promotional media strategies and methods' after the Corona-19 fandom, and found out if they could be applied to other sports events. As a method of research, the promotional media strategy of martial arts mastership was divided into types and in-depth interviews with media agents were conducted. According to the study, hosting an online martial arts competition, building an untact convention platform, and a base education facility can be a successful contest with budget support. Martial arts branding, popularization and industrialization can be a new attempt if ideas and execution personnel are sufficient. If IT technology and Chungbuk martial arts infrastructure are combined, they will be able to pioneer a new model called 'non-face-to-face-to K-sports'.

Parameterization of the Company's Business Model for Machine Learning-Based Marketing Stress Testing

  • Menkova, Krystyna;Zozulov, Oleksandr
    • International Journal of Computer Science & Network Security
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    • v.22 no.2
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    • pp.318-326
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    • 2022
  • Marketing stress testing is a new method of identifying the company's strengths and weaknesses in a turbulent environment. Technically, this is a complex procedure, so it involves artificial intelligence and machine learning. The main problem is currently the development of methodological approaches to the development of the company's digital model, which will provide a framework for machine learning. The aim of the study was to identify and develop an author's approach to the parameterization of the company's business processes for machine learning-based marketing stress testing. This aim provided the company's activities to be considered as a set of elements (business processes, products) and factors that affect them (marketing environment). The article proposes an author's approach to the parameterization of the company's business processes for machine learning-based marketing stress testing. The proposed approach includes four main elements that are subject to parameterization: elements of the company's internal environment, factors of the marketing environment, the company' core competency and factors impacting the company. Matrices for evaluating the results of the work of expert groups to determine the degree of influence of the marketing environment factors were developed. It is proposed to distinguish between mega-level, macro-level, meso-level and micro-level factors depending on the degree of impact on the company. The methodological limitation of the study is that it involves the modelling method as the only one possible at this stage of the study. The implementation limitation is that the proposed approach can only be used if the company plans to use machine learning for marketing stress testing.

Nanosulfated Silica as a Potential Heterogeneous Catalyst for the Synthesis of Nitrobenzene

  • Khairul Amri;Aan Sabilladin;Remi Ayu Pratika;Ari Sudarmanto;Hilda Ismail;Budhijanto;Mega Fia Lestari;Won-Chun Oh;Karna Wijaya
    • Korean Journal of Materials Research
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    • v.33 no.7
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    • pp.265-272
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    • 2023
  • In this study, the synthesis of nitrobenzene was carried out using sulfated silica catalyst. The study delved into H2SO4/SiO2 as a solid acid catalyst and the effect of its weight variation, as well as the use of a microwave batch reactor in the synthesis of nitrobenzene. SiO2 was prepared using the sol-gel method from TEOS precursor. The formed gel was then refluxed with methanol and calcined at a temperature of 600 ℃. SiO2 with a 200-mesh size was impregnated with 98 % H2SO4 by mixing for 1 h. The resulting 33 % (w/w) H2SO4/SiO2 catalyst was separated by centrifugation, dried, and calcined at 600 ℃. The catalyst was then used as a solid acid catalyst in the synthesis of nitrobenzene. The weights of catalyst used were 0.5; 1; and 1.5 grams. The synthesis of nitrobenzene was carried out with a 1:3 ratio of benzene to nitric acid in a microwave batch reactor at 60 ℃ for 5 h. The resulting nitrobenzene liquid was analyzed using GC-MS to determine the selectivity of the catalyst. Likewise, the use of a microwave batch reactor was found to be appropriate and successful for the synthesis of nitrobenzene. The thermal energy produced by the microwave batch reactor was efficient enough to be used for the nitration reaction. Reactivity and selectivity tests demonstrated that 1 g of H2SO4/SiO2 could generate an average benzene conversion of 40.33 %.

Prevalence of canine heartworm infection among dogs on breeding farms in Chungnam province (충남지역 집단 번식농장 사육견의 심장사상충 감염률 조사)

  • Lee, Jong-Hoon;Sim, Sang-Won;Kim, Hui;Kim, Young-Jin;An, Shin-Uk;Han, Kwei-Sup
    • Korean Journal of Veterinary Service
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    • v.26 no.1
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    • pp.19-26
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    • 2003
  • This study was attempted to survey on the prevalence of canine heartworm(Dirofilaria immitis) infection among 100 dogs(male 39, female 61) on the nine breeding farms in eastern Chungnam province in December 2002. Blood samples taken from dogs were examined for the presence of D immitis microfilaria by the modified Knott's test and an antigen test was using FASTest$\^$/ HW Antigne kit (Mega Cor A-6912 Horbranz-Austraia). 1. Eleven(11.0%) of the 100 examined dogs were microfilaria positive, while nineteen dogs(19.0%) were antigen positive, which suggested that the antigen test was more sensitive than the microfilarial test in detecting heartworm infection. 2. Infected dogs were observed higher more at 2 years older ages(4/48, 8.3%) and male(9/39, 23.1%) than young ages(4/48, 8.3%) and female(10/61, 16.4%). 3. The regional infection rates were of Gongju(15/43, 34.9%), Geumsan(4.27, 14.8%), while none of infection dogs in Yeongi(0/30, 0%). 4. Survey for hematological values of D immitis infected dogs : WBC and eosinophils were 21.4${\pm}$7.2 k/${\mu}\ell$, 3.5${\pm}$0.4 k/${\mu}\ell$, respectively. In conculsion, this study could be overemphasized the importance of control program the heartworm in eastern Chungnam province

Numerical Investigation on Combined Load Carrying Capacity and Consolidation Behavior of Suction Piles (석션파일의 조합하중 지지력 및 압밀거동에 관한 수치해석 연구)

  • Yoo, Chung-Sik;Hong, Seung-Rok
    • Journal of the Korean Geotechnical Society
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    • v.30 no.1
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    • pp.103-116
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    • 2014
  • This paper presents the results of a numerical investigation on the load carrying capacity and consolidation behavior of suction piles. Three dimensional numerical models which reflect realistic ground conditions and installation procedures including the ground-suction pile interface were adopted to conduct a parametric study on variables such as the length-diameter ratio and the loading configurations, i.e, vertical, horizontal, and combined loads. The results indicated that the load carrying capacity of a suction pile can only be realistically obtained when the interface behavior between the suction pile and the ground is correctly modeled. Also carried out was the stress-pore pressure coupled analysis to investigate the consolidation behavior of the suction pile after the application of a vertical loading. Based on the results, failure envelops and associated equations were developed, which can be used to estimate load carrying capacity of suction piles installed in similar conditions considered in this study. The results of consolidation analysis based on the stress-pore pressure coupled analysis indicate that no significant excess pore pressure and associated consolidation settlement occur for the loading configuration considered in part due to the load transfer mechanism of the suction pile.

Evaluation on the Maximum Yield Strength of Steel Stirrups in Reinforced Concrete Beams (철근콘크리트 보에 사용된 전단보강철근의 항복강도 제한에 대한 평가)

  • Lee, Jin-Eun;Lee, Jung-Yoon
    • Journal of the Korea Concrete Institute
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    • v.24 no.6
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    • pp.685-693
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    • 2012
  • The yield strength of shear reinforcement is restricted in the present design codes. In this study, the possibility of the yield strength increase in shear reinforcement is evaluated according to ACI318-08, EC2-02 and CSA-04 by comparing the experimental and calculated results. Three cases were used to analyze the shear strength of the beam. One had no limitation in the yield strength of shear reinforcement, another had restriction on the yield strength of shear reinforcement, and the other had a restriction on the yield strength of shear reinforcement and the shear reinforcement ratio. The study results showed that the case with unlimited shear reinforcement yield strength predicted the test result better than other two cases. Even though the rebar yield strength higher than the strength required in present code was applied to existing shear design equation, the result was reasonable. Therefore, the design equation seemed to be appropriate even if the high-strength shear reinforcement is used in practice based on the existing shear design method.

A Correlation Study of Clinical Outcomes by Quantification of Fatty Degeneration of the Subscapularis: Partial vs. Whole Cross-section

  • Park, Joo Hyun;Lee, Kwang Yeol;Rhee, Sung Min;Oh, Joo Han
    • Clinics in Shoulder and Elbow
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    • v.21 no.2
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    • pp.67-74
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    • 2018
  • Background: Fatty degeneration of rotator cuff is a well-known predictor of postoperative outcome. The purpose of this study was to evaluate the clinical features of rotator cuff tears involving subscapularis, and investigate whether fatty degeneration quantified from only the upper subscapularis correlates better with clinical outcomes than quantified from the whole subscapularis. Methods: We retrospectively analyzed 315 consecutive patients who underwent arthroscopic repair for rotator cuff tears involving subscapularis with a minimum follow-up of 1 year. Preoperative and postoperative visual analogue score for pain, range of motion and functional scores were assessed. Integrity of the repaired tendon was assessed at the 1-year follow-up with either magnetic resonance imaging or ultrasonography. Results: The mean Goutallier grade of whole cross-section was significantly lower than that of upper cross-section (1.59 vs. 1.71, p<0.05), but significantly higher than that of lower cross-section (1.59 vs. 1.01, p<0.05). In analysis of 37 re-tears, the occupancy of severe fatty degeneration in upper cross-section was 86.5%, which was significantly higher than that seen in whole cross-section (56.8%, p<0.05). We calculated the cut-off tear size for prediction of re-tears as 19.0 mm for retraction and 11.0 mm for superior-inferior. The cut-off Goutallier grade was 2.5 for both whole and upper cross-sections, but area under the curve was greater in the upper cross-section than the whole (0.911 vs. 0.807). Conclusions: As fatty degeneration of upper subscapularis demonstrated a more distinct spectrum than whole subscapularis, we suggest that measuring fatty degeneration of upper subscapularis can be a more useful method to predict clinical prognosis.

A Study on the Current Status of Application of Construction Management in Pusan National University Yangsan Hospital and Guidelines for CM Improvement (양산 부산대학교병원의 건설사업관리 적용현황과 발전 방향)

  • Park, Jong-Soon;Shin, Chang-Joon;Yoo, Byeong-Gi;Chun, Jae-Youl
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • 2008.11a
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    • pp.5-12
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    • 2008
  • The construction of Pusan National University Yangsan Hospital is a new construction of a medical town in Yangsan. It is a case that CMr participated in the project from planning to post-completion. It shows an actual proof of Construction Management business applied CM by each phase. In this case, CMr selected the design-build contractor in the planning phase and technically performed CM businesses in every single phase such as design and construction schedule management regarding application of Fast Track technique, procurement management and contract administration in phases based on the Fast-tract; technique, design review, VE in the design phase, change order management in the construction phase and operating and maintenance in the post-construction phase. This study would go far toward applying CM to Mega Turnkey projects by analyzing the problems of CMr's practical application to the project and providing guidelines for effective and efficient CM business implementation especially in the Turnkey projects.

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