• Advances in materials Research
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• 제4권1호
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• pp.23-30
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• 2015

Energy absorption and exposure buildup factor have been computed for natural uranium in the energy range of 0.05-15MeV up to penetration depth of 40 mfp. Five-parameter geometric progression (G-P) fitting method has been used to compute buildup factors of uranium. The variation of energy absorption and exposure buildup factors with, penetration depth and incident photon energies for the uranium has been studied. It has been concluded that the values of energy absorption and exposure buildup factors are very large at 0.15 MeV.

• 소성∙가공
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• 제9권5호
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• pp.486-493
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• 2000

Extrusion die-lip buildup has direct and negative impact on the properties of the final product. At the present time there is no absolute method of die-lip prevention. However, a Periodical shut down of extrusion line for the removal has been the general practice throughout the industry in concern. In this study the die-lip buildup was Investigated with a particular attention paid to the influence of die exit geometry and dimensions on the stresses produced at the point of die exit. To demonstrate the relationship between the stress state and the magnitude of the die-lip buildup, a method of virtual manufacturing was performed, assuming elastic-plastic material behavior for the high-density polyethylene under investigation. The overall numerical results suggested that the longer the die-land and/or the smaller the areal reduction of the die would reduce the tendency for the die-lip formation. Similarly, haying a fillet around the circumferential edge of the die exit would be favorable in decreasing the die-lip buildup.

• Nuclear Engineering and Technology
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• 제55권12호
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• pp.4426-4430
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• 2023

In this article, Exposure Buildup Factor(EBF) and the Energy Absorption Buildup Factor(EABF) have been determined for blood, brain, and muscle using the Monte Carlo method which is represented by MCNP5 codes and compared with geometric progression(G-P) fitting method which is represented by Phy-X/PSD online platform. The novelty of the present work is used an energy source of less than 0.1 MeV to determine buildup factors using MCNP5 and using Phy-X/PSD for some human tissues. thus, the energy range used in this case study was 0.06-3 MeV for penetration depths covered 0.5-3 MFP. Results of MCNP5 and Phy-X/PSD are validated against reference values of water that were reported at ANS-6.4.3. present results of EABFs and EBFs for the previously mentioned human tissues appeared good agreement between MCNP5 in comparison with Phy-X/PSD, whereas, the maximum average relative deviation did not exceed 2.37%. results of our article can be used in different medical applications, such as brachytherapy, radiotherapy, and diagnostics.

• Nuclear Engineering and Technology
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• 제53권11호
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• pp.3808-3815
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• 2021

In this paper, the EPICS2017 photoatomic database was used to evaluate the photon mass attenuation coefficients and buildup factors of soils collected at different depths in the Philippine islands. The extraction and interpolation of the library was accomplished at the recommended linear-linear scales to obtain the incoherent and total cross section and mass attenuation coefficient. The buildup factors were evaluated using the G-P fitting method in ANSI/ANS-6.4.3. An agreement was achieved between XCOM, MCNP5, and EPICS2017 for the calculated mass attenuation coefficient values. The buildup factors were reported at several penetration depths within the standard energy grid. The highest values of both buildup factor classifications were found in the energy range between 100 and 400 keV where incoherent scattering interaction probabilities are predominant, and least at the region of predominant photoionization events. The buildup factors were examined as a function of different soil silica contents. The soil samples with larger silica concentrations were found to have higher buildup factor values and hence lower shielding characteristics, while conversely, those with the least silica contents have increased shielding characteristics brought by the increased proportions of the abundant heavier oxides.

• Corrosion Science and Technology
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• 제23권2호
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• pp.83-92
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• 2024

A hot-dip simulator was utilized to replicate abnormal coating buildup observed during line stops at galvanize lines, assessing the influence of processing conditions on buildup (up to 14 mm/side). Steel samples from 19 coils (comprising IF, BH, LCAK, HSLA, DP600-DP1180, Si: 0.006 - 0.8 wt%, P: 0.009 - 0.045 wt%) were examined to explore the phenomenon of heavy coating growth. It was discovered that heavy coating buildup (~3 mm/h) and rapid strip dissolution (~0.17 mm/h) in a GA or GI pot can manifest with specific combinations of steel chemistry and processing conditions. The results reveal the formation of a unique coating microstructure, characterized by a blend of bulky Zeta crystals and free Zn pockets/networks due to the "Sandlin" growth mechanism. Key variables contributing to abnormal coating growth include steel Si content, anneal temperature, dew point in heating and soaking furnaces, Zn pot temperature, Zn bath Al%, and cold-rolling reduction%. At ArcelorMittal Dofasco galvanize lines, an automatic online warning system for operators and special scheduling for incoming Si-bearing steels have been implemented, effectively preventing further heavy buildup occurrences.

• Advances in materials Research
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• 제2권2호
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• pp.93-98
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• 2013

Objective of this study is to calculate gamma buildup factors for pointed and isotropic gamma sources in depleted uranium, uranium dioxide, natural uranium, tin, water and concrete using MCNP4C code. The thickness of the media ranges from 0.5 to 10 mean-free-path (mfp) and gamma energy ranges from 0.5 to 10 MeV. Owing to the outstanding accuracy of MCNP in calculation involving gamma interaction, results fairly match those reported previously. The maximum relative error is 2%.

• Journal of Multimedia Information System
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• 제8권1호
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• pp.11-16
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• 2021

This study developed a design to estimate the location of rescue demander using the sound system at disaster site, in the conditions of indoor positioning cannot be performed properly. It is a location tracing system through smart phone application. It generates sound wave information of rescuer at the rescue site, and it can be used as assistant means for indoor location tracing at the disaster site using sound wave receiving measurement technology.

• 대한간호
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• 제36권2호
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• pp.49-63
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• 1997

This study was performed to provide preliminary data for the development of a useful instrument to measure the effect of sex education. The study was conducted with the voluntary participation of 155 college students enrolled in the course "Sexuality and Relationship" at Y university in Seoul. At the end of that course, they were asked to write freely about the change they had experienced on sexuality. All meaningful statements were elicited and classified into 7 categories; "Change of Knowledge", "Enlightenment", "Change of Attitude on Sexuality", "Buildup of Ability", "Buildup of. Identity", "Change of Emotion", "Change of Behavior:' There were significant changes in the areas of knowledge(28. 6%), enlightenment(27.4%), and attitudes(20.3%) about sexuality among these 7 categories. The Change of Knowledge category consists of 3 areas: "concretion of knowledge", "increase of information", and "correction of misunderstanding." In the category of Enlightenment, total 12 areas are included: "sex role", "erception of lack of knowledge", "importance of family", "life plan", "parent role", "value of life", "equality", "sexual autonomy", "importance of sexuality", "freedom of sexuality", "perception of sexual problem", and "meaning of love." The Attitude Change category consists of 8 areas. These are "being natural", "being progressive", "being sensitive", "being truthful", "being expressive", "being cautious", "being responsible", and "being confident". The category of Buildup of Ability includes 4 areas: "problem solving", "sex education", "relationship", and "communication". The category of Buildup of Identity includes "sexual identity", and "value of sexuality". The Emotional Change category includes 3 areas: "positive feeling", "negative feeling", and "breaking from negative feeling on sexuality". The Behavior Change category includes "sex-related behavioral change". In conclusion, up to now most researches on sex education effect measures only changes of knowledge, attitude, and behavior. But we believe the changes in "Enlightenment", "Buildup of Ability", "Buildup of Identity", "Change of Emotion", should be included in addition to knowledge, attitude, and behavior in the development of an instrument to measure the sex education effects. And the effect of sex education should measure the degree of learning of autonomy, enlightenment, and ability of behavior and so on rather than studying the simple changes in sexuality.enment", "Buildup of Ability", "Buildup of Identity", "Change of Emotion", should be included in addition to knowledge, attitude, and behavior in the development of an instrument to measure the sex education effects. And the effect of sex education should measure the degree of learning of autonomy, enlightenment, and ability of behavior and so on rather than studying the simple changes in sexuality.ng the simple changes in sexuality.

• 벤처창업연구
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• 제16권5호
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• pp.49-59
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• 2021

산학협력 네트워킹을 통해 기업 구성원들의 경영인식, 시스템구축, 전략 운영이 기업성과에 미치는 영향력의 관계성을 연구하여 증명하였다.. 연구 결과 첫째, 산학협력 네트워킹의 중요성으로 시스템구축은 기업성과에 가장 큰 영향력을 제공하고 있는 것으로 나타났다. 둘째, 산학협력으로 구축된 기업 경영 인식의 구성원 공감 형성이다. 기업 경영 인식은 기업의 전략적 운영과정에서 중요한 요인으로 제시되었다. 셋째, 전략 운영의 중요성이다. 전략 운영은 기업성과와의 관계성이 높은 것으로 증명되었다. 넷째, 산학협력 네트워킹의 시스템구축과 전략운영과의 관계성을 증명하였다. 시스템구축은 기업의 전략 운영에 중요한 영향력을 제공한다. 다섯째, 산학협력으로 도출된 경영인식을 통한 시스템구축이다. 구성원들의 경영인식은 시스템구축에 유의한 영향력을 제공하는 것으로 나타났다. 마지막으로 경영인식과 기업성과 간의 관계성도 유의한 것으로 나타났다. 구성원들의 경영인식은 기업의 성과에 중요한 변수로 제안한다. 코로나 팬데믹 환경에서 중소기업이 가지는 구성원들의 경영인식은 기업성과에 높은 영향력을 제공하는 것으로 확인되었으며, 현장 개선과 정보 자산의 지속적 확보는 중소기업의 경쟁우위를 확보하는 주요 변수로 제안된다. 본 연구는 중소기업의 한계점을 산학협력을 통해 혁신성장의 기반을 마련하고 현장 중심의 창조적 프로세스 개선 방법과 구성원들과의 경영인식 공감대 형성, 프로그램 시스템 구축을 통한 중소기업의 경쟁력 확보 강화방안을 제안하였다는데 의의가 있다.

• 대한의용생체공학회:의공학회지
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• 제38권5호
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• pp.256-263
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• 2017

By using the buildup characteristics of the radiophotoluminescence glass dosimeter(RPLGD), it is aimed to help the measurement of the accurate dose by measuring the radiation dose according to the time of the glass element. Five glass elements were arranged on the table and the source to image receptor distance(SID) was set to 100 cm for the build-up radiation dose measurement of the fluorescent glass dosimeter glass element(GD-352M). Radiation doses and saturation rates were measured over time according to irradiation time, with the tube voltage (30, 60, 90 kVp) and tube current (50, 100 mAs) Repeatability test was repeated ten times to measure the coefficient of variation. The radiation dose increased from 0.182 mGy to 12.902 mGy and the saturation rate increased from 58.3% with increasing exposure condition and time. The coefficient of variation of the glass elements of the fluorescent glass dosimeter was ranged from 0.2 to 0.77 according to the X - ray exposure conditions. X - ray exposure showed that the radiation dose and saturation rate were increased with buildup characteristics, and degeneration of glass elements was not observed. The reproducibility of the variation coefficient of the radiation generator was included within the error range and the reproducibility of the radiation dose was excellent.