• Title/Summary/Keyword: material tests

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Readability of Patient Information Leaflets in Clinical Trials (임상시험 시험대상자설명서의 가독성 평가)

  • Choi, Im-Soon;Yong, Chul-Soon;Lee, Iyn-Hyang
    • Korean Journal of Clinical Pharmacy
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    • v.26 no.1
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    • pp.33-39
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    • 2016
  • Background: Elements of informed consent including capacity, disclosure, understanding, voluntariness, and permission of the participant, are all crucial for clinical trials to be legally and ethically valid. During the informed consent process, the patient information leaflet is an important information source which prospective research subjects can utilize in their decision-making. In the adequate provision of information, KGCP guideline necessitate 20 specific items, as well as the use language that individuals can understand. This study measures the vocabulary level of patient information leaflets in an effort to provide an objective evaluation on the readability of such material. Methods: The word difficulty of 13 leaflets was quantitatively evaluated using Kim kwang Hae's vocabulary grading framework, which was compared to the difficulty level of words found in the $6^{th}$ grade Korean textbook. The quantitative outcomes were statistically analyzed using chi-squared tests and linear by linear association for ordinal data. Results: There was a statistically significant difference between the vocabulary level and frequency of words in leaflets and the 6th Korean textbook. The leaflets were on average 260 sentences and about roughly 15 pages long, including lay language (easier or equal to language used in primary school) of around 12% less; technical language of around 4.5% more. As the vocabulary grades increase, there was a distinct difference in vocabulary level between Korean textbook and each information leaflet (p < 0.001). Conclusion: Patient information leaflets may fail to provide appropriate information for self-determination by clinical trial subject through the difficulty level of its wording. Improvements in the degree of patients' understanding and appropriate use of information leaflets are collaboratively equipped to strengthen patient's autonomy and therefore guaranteeing participant's rights.

Fracture Behavior of a Stacked Concrete Structure Based on the Fracture Mechanics (적층한 콘크리트 복합구조체의 파괴역학적 거동)

  • Kim, Sang-Chul;Kim, Yeon-Tae
    • Magazine of the Korea Concrete Institute
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    • v.11 no.1
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    • pp.119-127
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    • 1999
  • The objective of this study is to simulate the fracture behavior of composite structure bonded with more than 2 different cementitious materials. For this, concrete and cement were stacked and bonded in a direction perpendicular to loading and specimens were tested. Each constituent material of concrete and cement was fabricated independently also, and three point bending and indirect tensile tests were carried out for the acquisition of measured values applicable to the proposed model. As a result of comparing theoretical results and experimental ones, it was found that the proposed model derived from fictitious crack theory can be used to predict the fracture behavior of composite structures on the vases of well agreement with experimental results. It was also noted that the degree of improvement of fracture energies and strengths is greatly dependent on the stacking sequence of layers composing of a composite structure. Thus, it can be concluded that brittleness or ductility of a composite structure can be accomplished by a proper arrangement of layers on one's purpose throughout the proposed analysis.

Reliability Enhancement of Anisotropic Conductive Adhesives Flip Chip on Organic Substrates by Non-Conducting Filler Additions

  • Paik, Kyung-Wook;Yim, Myung-Jin
    • Proceedings of the International Microelectronics And Packaging Society Conference
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    • 2000.04a
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    • pp.9-15
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    • 2000
  • Flip chip assembly on organic substrates using ACAs have received much attentions due to many advantages such as easier processing, good electrical performance, lower cost, and low temperature processing compatible with organic substrates. ACAs are generally composed of epoxy polymer resin and small amount of conductive fillers (less than 10 wt. %). As a result, ACAs have almost the same CTE values as an epoxy material itself which are higher than conventional underfill materials which contains lots of fillers. Therefore, it is necessary to lower the CTE value of ACAs to obtain more reliable flip chip assembly on organic substrates using ACAs. To modify the ACA composite materials with some amount of conductive fillers, non-conductive fillers were incorporated into ACAs. In this paper, we investigated the effect of fillers on the thermo-mechanical properties of modified ACA composite materials and the reliability of flip chip assembly on organic substrates using modified ACA composite materials. For the characterization of modified ACAs composites with different content of non-conducting fillers, dynamic scanning calorimeter (DSC), and thermo-gravimetric analyzer (TGA), dynamic mechanical analyzer (DMA), and thermo-mechanical analyzer (TMA) were utilized. As the non-conducting filler content increased, CTE values decreased and storage modulus at room temperature increased. In addition, the increase in tile content of filler brought about the increase of Tg$^{DSC}$ and Tg$^{TMA}$. However, the TGA behaviors stayed almost the same. Contact resistance changes were measured during reliability tests such as thermal cycling, high humidity and temperature, and high temperature at dry condition. It was observed that reliability results were significant affected by CTEs of ACA materials especially at the thermal cycling test. Results showed that flip chip assembly using modified ACA composites with lower CTEs and higher modulus by loading non-conducting fillers exhibited better contact resistance behavior than conventional ACAs without non-conducting fillers.ers.

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Reliability Enhancement of Anisotropic Conductive Adhesives Flip Chip on Organic Substrates by Non-Conducting Filler Additions

  • Paik, Kyung-Wook;Yim, Myung-Jin
    • Journal of the Microelectronics and Packaging Society
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    • v.7 no.1
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    • pp.41-49
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    • 2000
  • Flip chip assembly on organic substrates using ACAs have received much attentions due to many advantages such as easier processing, good electrical performance, lower cost, and low temperature processing compatible with organic substrates. ACAs are generally composed of epoxy polymer resin and small amount of conductive fillers (less than 10 wt.%). As a result, ACAs have almost the same CTE values as an epoxy material itself which are higher than conventional underfill materials which contains lots of fillers. Therefore, it is necessary to lower the CTE value of ACAs to obtain more reliable flip chip assembly on organic substrates using ACAs. To modify the ACA composite materials with some amount of conductive fillers, non-conductive fillers were incorporated into ACAs. In this paper, we investigated the effect of fillers on the thermo-mechanical properties of modified ACA composite materials and the reliability of flip chip assembly on organic substrates using modified ACA composite materials. For the characterization of modified ACAs composites with different content of non-conducting fillers, dynamic scanning calorimeter (DSC), and thermo-gravimetric analyser (TGA), dynamic mechanical analyzer (DMA), and thermo-mechanical analyzer (TMA) were utilized. As the non-conducting filler content increased, CTE values decreased and storage modulus at room temperature increased. In addition, the increase in the content of filler brought about the increase of $Tg^{DSC}$ and $Tg^{TMA}$. However, the TGA behaviors stayed almost the same. Contact resistance changes were measured during reliability tests such as thermal cycling, high humidity and temperature, and high temperature at dry condition. It was observed that reliability results were significantly affected by CTEs of ACA materials especially at the thermal cycling test. Results showed that flip chip assembly using modified ACA composites with lower CTEs and higher modulus by loading non-conducting fillers exhibited better contact resistance behavior than conventional ACAs without non-conducting fillers.

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An Experimental Study on Suppression of Cavity Development by Enlargement of Base Plate of Box-Culvert Installed at River Levee (하천제방 배수통문의 저판확폭을 통한 공동발생 억제기법 연구)

  • Kim, Jin-Man;Choi, Bong-Hyuck;Lee, Dae-Young;Jin, Young-Ji
    • Journal of the Korean Geotechnical Society
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    • v.27 no.3
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    • pp.55-61
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    • 2011
  • Generally, the Box-Culvert in levee is destroyed by various reasons. Especially when Box-Culvert is installed over the pile foundation in soft ground, the failure occurrs for 1) the weakness of compaction in Box-Culvert side by the differential settlement between outer ground and inner soil prism, 2) hydraulic fracturing and disturbance of Box-Culvert side soil by the repeated acting of seepage pressure at flood time. Also the side of Box-Culvert is difficult to compact and the shear resistance is reduced by more than 1/3 for the reduction of friction caused by the difference of material property. In this study, a series of model tests are conducted for the analysis of the development mechanism of outer ground and inner soil prism by the differential settlement using the pile foundation in soft ground, and cavity suppressed technique is suggested by the analysis of base plate enlargement effect.

THE COMPARATIVE STUDY OF THERMAL INDUCTIVE EFFECT BETWEEN INTERNAL CONNECTION AND EXTERNAL CONNECTION IMPLANT IN ABUTMENT PREPARATION (구강내에서 임플랜트 지대주 형성 시 내부연결방식과 외부연결방식간의 열전달 효과 비교)

  • Huh, Jung-Bo;Ko, Sok-Min
    • The Journal of Korean Academy of Prosthodontics
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    • v.45 no.1
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    • pp.60-70
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    • 2007
  • Statement of problem: The cement-type abutment would be needed for the reduction of its body in order to correct the axis and to assure occlusal clearance. In the case of intraoral preparation, there is a potential risk that generated heat could be transmitted into the bone-implant interface, where it can cause deterioration of tissues around the implant and failed osseointegration. Purpose: The purpose of this study was to assess the difference of the heat transmitting effect on external and internal connection implant types under various conditions. Material and method: For evaluating the effects of alternating temperature, the thermocoupling wires were attached on 3 areas of the implant fixture surface corresponding to the cervical, middle, and apex. The abutments were removed 1mm in depth horizontally with diamond burs and were polished for 30 seconds at low speed with silicone points using pressure as applied in routine clinical practice. Obtained data were analyzed using Mann-Whitney rank-sum test and Wilcoxon / Kruskal-Wallis Tests. Result: Increased temperature on bone-implant interface was evident without air-water spray coolant both at high speed reduction and low speed polishing (p<.05). But, the difference between connection types was not shown. Conclusion: The reduction procedure of abutment without using proper coolant leads to serious damage of oral tissues around the implant irrespective of external and internal connection type.

Effects of simulation based education, for emergency care of patients with dyspnea, on knowledge and performance confidence of nursing students (호흡곤란 응급관리에 대한 시뮬레이션기반 교육이 간호학생의 지식과 수행자신감에 미치는 효과)

  • Hur, Hea-Kung;Park, So-Mi
    • The Journal of Korean Academic Society of Nursing Education
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    • v.18 no.1
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    • pp.111-119
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    • 2012
  • Purpose: The purpose of this study was to identify the effects on knowledge and performance confidence of nursing students in the emergency care of patients with dyspnea after simulation education using a human simulator. Method: The research design was a nonequivalent control group pretest-posttest design. For the experimental group the human simulator was used to provide simulation. Also included were base learning with audio-visual material, explanations about simulation, using SimMan for human simulation, and debriefing. Pre and post-tests were conducted to compare differences in knowledge and performance confidence. Result: The (t=3.83, p<.000) than the control group. For the experimental group, the differences in pretest-posttest scores for knowledge (t=2.30, p=.025) and performance confidence (t=4.28, p<.000) were significantly higher than the experimental group had significantly higher scores for knowledge (t=3.03, p=.004) and performance confidence (t=3.83, p<.001knowledge (t=2.30, p=.025) and performance confidence (t=4.28, p<.000) were significantly higher than the control group. Conclusion: The results of this study indicate that for student nurses, knowledge and performance confidence in emergency care of patients with dyspnea improve with human simulator simulation education. Further study is suggested to develop other scenarios for emergency care and identify the effects of critical thinking and satisfaction when using human simulator simulation education.

Clothing Temperature Changes of Phase Change Material-Treated Warm-up in Cold and Warm Environments

  • Choi Kyeyoun;Chung Hyejin;Lee Boram;Chung Kyunghee;Cho Gilsoo;Park Mikyung;Kim Yonkyu;Watanuki Shigeki
    • Fibers and Polymers
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    • v.6 no.4
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    • pp.343-347
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    • 2005
  • The purpose of this study was to investigate the appropriate amounts of phase change materials to give objective and subjective wear sensations. Vapor-permeable water-repellent fabrics with (WR-PCM) and without (WR) octadecane containing microcapsules were obtained by wet-porous coating process. Then, calculating the area of the WR-PCM treated clothes, we estimated the total calories of the clothing by multiplying the heat of fusion and heat of crystallization of PCM to the calculated area. Wear tests were conducted in both warm environment $(30^{\circ}C,\;65\%\;RH)$ and cold environment $(5^{\circ}C,\;65\%\;RH)$ with sports warm up style experimental garments made with WR and WR-PCM fabrics. Rectal, skin, and clothing microclimate temperatures, saliva and subjective evaluation measurements were done during the wear test. There was no difference of rectal and mean skin temperatures between WR and WR-PCM, but the clothing microclimate temperature of WR-PCM under warm environment was slightly lower than that of WR. In cold environment, WR-PCM showed much higher temperature than in WR. Saliva change did not appear between clothes, but did between two environments. Although subjective sensation between WR and WR-PCM was not significantly different, WR-PCM was rated as cooler than WR in warm environment and as warmer than WR in cold environment. The results of this study indicated that octadecane containing microcapsules in water-repellent fabric provide cooling effect.

Effect of Anti-washout Admixture Implementation on Backfill Aggregates on Underwater Structures (수중 구조물 골재 속채움 시 수중 불분리성 혼화제의 적용 효과)

  • Kim, Ukgie;Choi, Changho;Park, Bonggeun;Li, Zhuang;Cho, Samdeok
    • Journal of the Korean GEO-environmental Society
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    • v.15 no.9
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    • pp.59-67
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    • 2014
  • With increasing underwater structure construction, there is high interest in offshore foundation and underwater grout and various study has been done in this area. For grout materials constructed underwater, it may be washed away by water or easily disturbed and material separation phenomenon during curing period always happens. As a result, it is difficult to ensure construction quality and this has a significant influence on the design strength of structure. In this study, to understand application effects of anti-washout admixture for the preplaced construction method, where grout is injected in monopile after filled with aggregates, laboratory tests on bleeding and compressive strength of anti-washout admixture were performed under various test conditions varying size of aggregate, water and cement ratio and admixture, and test results were compared and evaluated.

Application of Paper Sludge Ash-Stabilized Soft Ground for Subgrade Soil (제지애쉬 고화제로 안정처리된 연약지반의 도로노상토 적용에 관한 연구)

  • Shin, Eunchul;Park, Sooyoung
    • Journal of the Korean GEO-environmental Society
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    • v.19 no.6
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    • pp.13-22
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    • 2018
  • The southwestern part of Korean Peninsula, which length is about 13,000 km, is largely formed with soft cohesive soil ground and when it is developed, the low bearing capacity and excessive settlement of soft ground give many problems. In particular, a lot of clayey soil is deserted due to high moisture content and weakness, and areas formed with soft ground. In this study it was performed unconfined compression test, CBR tests, laboratory frost heaving test, and wheel tracking test in order to determine the optimum mixture ratio of paper sludge ash added chemical stabilizer with soft soil for consideration of its frost heaving and strength characteristics. As a results of the above experiments, when the soft soil is mixed with 6% of chemical stabilizer to improve the soft soil for utilizing as a subgrade soil material. It is satisfied the quality standard of fill materials, and the results of this research are expected to be used as an appropriate usage standard for utilization of on-site soil generated.