• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.415-420
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• 2009

공학 분야에 있어서 수치 해석적 연구가 많은 주목을 받고 있다. 경제적 측면을 비롯한 다양한 측면에 있어서 모의의 간편성으로 인해 하천에서의 수리학적 거동모의에 수치해석 모의 분석법이 쓰이고 있는데 모의결과의 비교 및 검증을 위해서는 현장 실험 혹은 모형실험이 선행되어야만 한다. 본 연구에서는 강재로 제작된 S자 형태의 만곡부를 두 개 갖고 있는 사행수로 실험 장치를 제작하여 두 가지 유량조건 (30, 60 ${\ell}$/sec.)과 두 가지 하류단 수위조건 (30, 40 cm)에 대하여 수평 2차원 유속분포 자료를 이용하였다. 유속장의 자료는 Sontek사에의 3차원 micro-ADV(Acoustic Doppler Velocimeter)를 이용하여 측정하였다. 주 흐름은 직선구간에서는 중앙에서 최대 유속을 나타내며, 좌우대칭적인 유속분포의 모습을 보이고, 만곡부에서는 수로안쪽을 따라 최대유속이 발생하였다. 이는 만곡부의 정점부분에서의 이차류 발생 및 소멸에 의한 연직방향 유속분포를 통해 발생되는 현상이라 사료된다. 또한 본 연구에서는 2차원 하천해석 상용프로그램인 RAMS (베타버젼)와 SMS를 이용하여 흐름해석을 수행하였다. 실험 자료와의 비교를 통하여 두 가지 상용프로그램의 경우 모두 다소 과대 산정되는 것을 알 수 있었고, 만곡부와 직선부의 유속분포에 대한 모의결과는 RAMS (RAM2)의 결과가 보다 실험결과와 잘 일치하는 것으로 분석되었다. 위와 같은 유속분포의 분석을 통하여 각각의 상용소프트웨어의 적용성을 비교해 보았으며 향후 오염물질 거동해석 모형을 실험수로에 적용하여 그 결과를 비교할 수 있을 것으로 예상한다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.3
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• pp.457-463
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• 2016

The newly developed super ductile duplex stainless steel (SDSS) has good strength and ductility, and it can be used to reduce weight and improve the fabrication efficiency of a carbody of a rolling stock. In this study, spot weldability tests were conducted to take advantage of SDDSS in a carbody for an intermodal tram. Specimens of various thickness (0.4 to 5.0 mm) were prepared to find the proper welding conditions, and tensile load tests were conducted to evaluate the tensile-shear strength of spot welded joints. Then, nugget diameters were measured to verify the quality. The tensile-shear strength was found to be proportional to the heat parameter. It was verified that the tensile-shear strengths and nugget sizes of the joints satisfy the standard requirements. The overall weldability tests confirmed that SDDSS can be used effectively for the carbody of an intermodal tram.

• Journal of Digital Convergence
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• v.15 no.6
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• pp.369-376
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• 2017

In a digital multimedia environment with various experiences and communication, We live in an age where it is possible to experience from imagination to reality realizable by imagination. The remarkable technology based on ICT has been attracting attention as next generation video service technology from 3DTV, UHD TV, and hologram. These media, combined with space design, are able to offer us amazing and diverse experiences. In addition, now, there is a demand for more differentiated contents using human five senses recognition technology. We analyzed the application of realistic contents to space design. As a result, we have come to the conclusion that creative production which can express more fun and convenient will be an important issue.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.269-272
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• 2008

This paper reports on the cracking mitigation and flexural behavior experimentally observed in concrete prisms layered with strain-hardening cement composites (SHCCs) which is micro-mechanically designed cement composite and exhibits pseudo tensile strain-hardening behavior accompanied by multiple cracking while using a moderate amount of fiber, typically less than 2 percent in term of fiber volume fraction. In this study, SHCC is reinforced with 1.3 percent polyvinyl alcohol (PVA) and 0.20 percent polyethylene (PE) in volume fraction. Tests were conducted using $100{\times}100{\times}400mm$ long prisms supported over a simply supported span of 350mm. The four point load was applied using MTS servo control machine. The thickness patched with SHCC is the main variable for this study. Experimental study shows that when subject to monotonic flexural loading, the SHCC layered repair system showed 2.7 - 4.2 times increased load carrying capacity, and mitigated cracking damage of concrete beams layered with SHCC compared with plain concrete beams.

• Journal of the Korea Convergence Society
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• v.8 no.5
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• pp.137-143
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• 2017

Augmented reality makes people feel realistic and reduces the damage to cultural properties that can come into contact with the actual cultural heritage. Augmented reality has the advantage that it can show the past appearance of the historical building or relics, the environment, or related information in addition to the current real environment. Despite these values ​and advantages, As a result of researches and analyzes of the Augmented Reality contents of the National Museum, 'palace in my hand', and the Miruksa project In the field of domestic cultural heritage warriors, augmented reality technology has shown a very negative attitude such as simply showing cultural heritage content or using it as a guide. However, various conditions such as display and sensor hardware and technology needed to realize augmented reality more effectively are improving day by day. And If you have various facilities such as the idea of ​adding storytelling to the exhibits and WiFi building, In the near future, it will be equipped with a display system of cultural heritage contents that combines augmented reality with a more complete one.

• Journal of the Korea Convergence Society
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• v.9 no.1
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• pp.199-204
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• 2018

Smart phones that have lost their existing physical home buttons are being released at the same time, and the flow of users is also changing. The flow is highly subjective and can vary depending on the individual's tendencies. Therefore, this study investigated the change of the flow of smart phone users by Q methodology which is a method of subjectivity research. As a result, the proficiency level of how to turn on the power to start the screen showed a tendency to decrease the flow, and the playability, which is a result of curiosity about the new thing, The results were very positive in the continuity of navigation due to the use of software buttons instead of buttons. Therefore, it can be seen that the change in the hardware smartphone has a positive effect on the flow.

• Journal of Korean Association for Spatial Structures
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• v.10 no.1
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• pp.67-74
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• 2010

This paper focuses on steel arrays regarding the application of PV system for solar power system, a renewable energy in steel structure stadium that will be built in Korea, by foreign case study. 20 cases of Steel Structure Stadiums applying PV system after 1990 were selected as the main subjects. The 20 cases of Steel Structure Stadiums were categorized by rail systems that were installed to fix PV module. As the result, linear clamping and roof-integrated type among cross rails were 28% of the whole, followed by 17% of rail-fixed type and 11% of module group-fixed type among vertical-fixed types. In addition, linear clamping and roof-integrated type among cross rails were applied in the inside of the stadium while the outside and other parts of stadiums used angle bracket to fix PV module.

• YAKHAK HOEJI
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• v.55 no.4
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• pp.301-308
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• 2011

Diabetes has been one of major health risks in industrialized countries. AMP-activated protein kinase (AMPK) has been focused as a novel therapeutic target for the treatment of metabolic syndromes, because AMPK increases glucose uptake through independent insulin signal pathway. In this study, we investigated the anti-diabetic effect of Angelica gigas Nakai extract (AGNEX), a mixture of decursin and decursinol angelate (53 : 47), decursin and decursinol angelate on blood glucose, glucose transport (GLUT) and AMPK expression levels in streptozotocin (STZ)-induced diabetic rats. To induce diabetes, 50 mg/kg of STZ was injected via i.v. route and AGNEX 2 mg/kg (STZ+AG), decursin 2 mg/kg (STZ+D), decursinol angelate 2 mg/kg (STZ+DA), and metformin 100 mg/kg (STZ+M) were administered orally for 21 days. STZ+DA group showed a significant decrease in fasting blood glucose levels compared to the other groups. Decursinol angelate significantly upregulated expression of glucose transporter 4 (GLUT4) and phosphorylation of AMPK (p-AMPK) in skeletal muscle of rats. In pancreas of rats, decursinol angelate significantly increased expression of GLUT2 through down-regulation of p-AMPK. In addition to the result of pancreatic islets morphology, AGNEX, decursin, decursinol angelate, and metformin treated group recovered ${\beta}$-cell damage by hyperglycemia. These results indicate that decursinol angelate might be a potential anti-diabetic agent and AGNEX could be useful in the treatment of diabetes mellitus.

• Journal of Korean Society of Steel Construction
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• v.20 no.1
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• pp.183-193
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• 2008

The reliability analysis of simply-supported and continuous composite plate girder and box girder bridges under flexure was performed to provide a basic data for the development of LRFD c ode. The bridges were designed based on LRFD specification with newly proposed design live load which was developed by analyzing traffic statistics from highways and local roads. A performance function for flexural failure was expressed as a function of the flexural resistance of composite section and the design moments due to permanent load and live load. For the flexural resistance, the statistical parameters obtained by analyzing over 16,000 domestic structural steel samples were used. Several different values of bias factors for the live load moment from 1.0 to 1.2 were used. Due to the lack of available domestic measured data on the moment by permanent loads, the same statistical properties used in the calibration of ASHTO-LRFD were ap plied. The reliability indices for the composite girder bridges with various span lengths, different live load factors, and bias fact or for the live load were obtained by applying the Rackwitz-Fiessler technique.

• Journal of Applied Biological Chemistry
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• v.62 no.2
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• pp.123-127
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• 2019

Medicinal herb in Asian countries has been traditionally used for a long time. However, the safety and adverse effect of medicinal herb have not been established yet. The aim of this study is to evaluate toxicity in the oral administration of Clausena excavata (C. excavata) in male ICR mice for 3 weeks and the noobserved adverse effect level (NOAEL). C. excavata has been used as a medicinal herb for the treatment of dermatopathy, malaria, abdominal pain, dysentery, and enteritis. C. excavata was orally administered daily for 21 days at a dose of 100, 250, 500, 1000, and 2000 mg/kg/day (MPK). There were no significant differences in mortalities, clinical signs, body weight changes, hematological, and serum biochemistry examination in all animals administrated with C. excavate. Consequently, these findings indicated that C. excavata did not affect the toxic effect in ICR mice and the NOAEL of C. excavata was considered as more than 2000 MPK.