• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.4
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• pp.78-85
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• 2019

This study targets SFRC hollow members with small depth under shear force and bending. To evaluate the effect of web width on shear strength of SFRC members, experiment and finite element analysis were conducted and compared with existing equations. The web width was planned to be 1/2 times and 2/3 times, and the shear span ratio was planned to be 1.5 times. In the shear test results, the maximum shear strength increased by 10.3 to 28.0% with the web width increased by 33%. When the overall depth of specimens was increased by 1.5 times, the shear strength of the specimen with a web width of 100mm was increased by 29.2%. On the other hand, specimen with the 150mm only increased by 11.3%. These results indicate that the smaller the web width, the greater the shear strength increase with the increase of depth. Also, the smaller the web width, the greater the contribution of steel fiber. It has been shown that the KCI code evaluates the shear strength of experiments as very safe side, and that the proposed formula of Shin et al. predicts the experimental strength relatively well. As the web width increases by 2, 3, and 6 times, the mean shear strength by FEA appears to be 1.18, 1.80, and 2.19 times respectively. This indicates that the shear strength does not increase in proportion to the increase in web width.

• Journal of Korean Critical Care Nursing
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• v.12 no.3
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• pp.35-49
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• 2019

Purpose : This study aimed to propose a common scope of practice (SOP) for 13 specialties of Advanced Practice Nurses (APNs) in Korea. Methods : The first draft of a common SOP was extracted from domestic and international laws with a literature review by 17 experts from the Korean Association of Advanced Practice Nurses (KAAPN). Then, the common SOP was finalized after comparing the activities of APNs in clinical settings. Results : A total of 70 duties were identified and six categories were suggested for the common SOP. The SOP proposed by the KAAPN featured the following: 1) identification of and discrimination between health problems; 2) prescription and implementation of diagnostic tests; 3) treatment of injuries and diseases while implementing measures to prevent exacerbation; 4) prescription of medicinal products in line with 1) to 3); 5) referral and consultation; and 6) education and counseling. It was then confirmed that the proposed six categories in the common SOP reflected all the duties performed by APNs in clinical practice, including all 40 activities. Conclusion : The results of this study can be used as evidence for the legalization of a common SOP for APNs. Given the increasing multidisciplinary team approach adopted in Korean hospitals, it may be desirable to establish a broader SOP to reflect the diverse duties of APNs.

• Journal of the Korean Geotechnical Society
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• v.35 no.3
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• pp.5-16
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• 2019

With the recent concentration of urban populations, the constructions of large structures are increasing, along with the development of foundations for large structures. PHC Piles have been used in many structures ever since Japanese introduced the technology at the end of the 20th century. Recently, many studies on the use of the PHC Pile have been carried out as earth retaining using the merits of PHC piles. In this study, static axial compression tests were conducted on the PHC-W piles constructed as column-type in building underground additional wall using the PHC-W earth retaining wall. The end bearing capacity of pile was calculated using the axial load transfer measurement that was obtained from the static axial compression test result. Since end bearing capacity of the PHC-W pile embedded in weathered rock showed a different behaviour from the conventional PHC pile, the calculation method of end bearing capacity for column-type PHC-W piles would be proposed. The unit ultimate end bearing equation proposed for single and group PHC-W pile embedded in weathered rock is $q_b=13.3N_b$ and $q_b=6.8N_b$.

• Journal of the Korean Society of Radiology
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• v.13 no.1
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• pp.39-44
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• 2019

Radiation safety management is being considered very important since radioactive isotopes such as Co-60 and Ir-192 are widely used in fields such as non-destructive test(NDT). In this study, the applicability of Mercury(II) Iodide($HgI_2$) source for tracing system was evaluated. To make sure the unit cell sensor's reliability, we evaluated the electrical properties of the sensor made with $HgI_2$, and then position dependence of the sensor was analyzed and compared with the dose distribution from the planning system. As a result of the evaluation, high reliability of the sensor was shown through the linearity of R-sq > 0.990 and reproducibility of CV < 0.015. In the position dependence evaluation, the maximum value was measured at the isocenter of the sensor and gradually decreased according to the distance. However, the dose distribution data from the planning system was turned out that has difference with that of the sensor up to 30%. This seems to come from the difference between single-point measuring based planning system and area measuring based sensor.

• Journal of the Korean Society of Radiology
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• v.13 no.1
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• pp.119-124
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• 2019

Radiation therapy using flattening filter free beam can prevent beam attenuation caused by flattening filter and can improve treatment efficiency. However, accurate dose control is not established for nonuniform iso dose distributions. In this study, curved dosimeter based on photoconductive material $HgI_2$ was fabricated and its reproducibility and linearity were evaluated at 6 MV photon energy to verify its performance. In order to show the usefulness of the curved measurement, the signals measured on the flat substrate and the curved substrate were compared in the flattening filter free beam using the acrylic filter. As a result, the reproducibility of the unit cell dosimeter was evaluated as SE 0.613%, and the linearity was evaluated as R-sq 0.9999. The usability evaluation of the array curve dosimeter demonstrated its usefulness by indicating a curvature error rate of 11.073%p and a reduced error rate.

• Journal of the Korean Society of Radiology
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• v.13 no.1
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• pp.141-146
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• 2019

Radiation sources used in the field of industrial non-destructive pose a risk of exposure due to ageing equipment and operator carelessness. Thus, the need for a safety management system to trace the location of the source is being added. In this study, Monte Carlo Simulation was performed to analyse the angle dependence of the unit-cell comprising the line-array dosimeter for tracking the location of radiation sources. As a result, the margin of error for the top 10% of each slope was 5.90% at $0^{\circ}$, 8.08% at $30^{\circ}$, and 20.90% at $60^{\circ}$. The ratio of the total absorbed dose was 83.77% at $30^{\circ}$ and 53.36% at $60^{\circ}$ based on $0^{\circ}$(100%) and showed a tendency to decrease with increasing slope. For all gradients, the maximum number was shown at $30^{\circ}$ No. 9 pixels, and for No. 10, there was a tendency to drop 7.24 percent. This study has shown a large amount of angle dependence, and it is estimated that the proper distance between the source and line-array dosimeters should be maintained at a distance of not less than 1 cm to reduce them.

• Journal of Digital Convergence
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• v.17 no.1
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• pp.9-27
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• 2019

The purpose of this study is to examine consumers' responses to mobile payment services by using a text-mining technique focusing on Samsung Pay as it is used in both online and offline transactions. We conducted text frequency analysis, text clustering analysis, and text network analysis using R programming. The major findings are as follows. First, the most frequently used key words referenced the brand names of the mobile devices, the replacement of traditional wallets and unique functions of Samsung Pay. Second, there was a clear split between positive and negative responses at the macro level. Third, replacement of traditional wallets played a great role in the positive responses and continuous use of mobile payment services. This study provides in-depth understanding of consumer responses toward mobile payment services. It also offers practical implications that may help mobile payment marketers correspond to consumer values and expectations, thus increasing consumer satisfaction.

• Korean Journal of Construction Engineering and Management
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• v.22 no.2
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• pp.3-11
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• 2021

Myanmar is an undeveloped country with high development value among Asian countries. Therefore, various countries including the U.S. are considering entering the market. In this respect, demand for real estate development project is forecast to grow on increased inflow of foreigners and Myanmar's economic growth. However, Myanmar is a high-risk country in terms of overseas companies, including national risk. In this study, we conducted an in-depth interview with experts (law, finance, technology, and local experts) after analyzing data on Myanmar to extract risk-causing factors. Through this, 106 risk factors were extracted, and the final risk classification system was established by conducting three-time groupings using the affinity diagramming. And the relative importance of each factor was presented using the analytic hierarchy process (AHP) technique. As a result, the country-related risk, the fund-related risk, and the pre-sale-related risk were highly important. The research results are expected to provide risk management standards to companies entering the Myanmar real estate development type project.

• PNF and Movement
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• v.10 no.2
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• pp.9-16
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• 2012

본 연구는 43세 남성 환자의 관절가동술과 슬링을 이용한 유착성 관절낭염 환자의 치료사례를 조사하여 그 과정과 결과를 알아보고자 하였다. 어깨통증장애지수(shoulder pain and disability index) 측정과 어깨관절의 굽힘(flexion), 벌림(abduction), 바깥돌림(external rotation), 안쪽돌림(internal rotation)에 대한 관절가동범위를 측정하여 비교하였으며 견관절 주위에 비스테로이드 소염진통 주사 1회, 약물치료를 병행하며 주 3회 8주간 보존적인 물리치료인 온습포(hot pack)와 간섭파(ICT), 관절가동술, 그리고 슬링을 이용한 운동치료를 실시하였다. 결과는 관절가동술과 슬링운동치료의 적용이 유착성 관절낭염 환자의 통증을 줄이고 관절가동범위를 증진시키는데 효과가 있는 것으로 판단된다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.7
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• pp.471-478
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• 2022

This paper is about research and development of Korea Aerospace University's Solar-Powered UAV System that named of KAU-SPUAV, and describes the design process of the 4.2 m solar UAV that succeeded in a long flight of 32 hours and 19 minutes at June 2020. In order to improve the long-term flight performance of the KAU-SPUAV, For reduce drag, a circular cross-section of the fuselage was designed, and manufactured light and sturdy fuselage by applying a monocoque structure using a glass fiber composite material. In addition, a solar module optimized for the wing shape of a 4.2 m solar drone was constructed and arranged, and a propulsion system applied with the 23[in] × 23[in] propeller was constructed to improve charging and flight efficiency. The developed KAU-SPUAV consumes an average of 55W when cruising and can receive up to 165W of energy during the day, and its Long-term Endurance was verified through flight tests.