• Title/Summary/Keyword: experimental research

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Experimental and analytical investigation of high-strength concrete-filled steel tube square columns subjected to flexural loading

  • Chung, Kyung-Soo;Kim, Jin-Ho;Yoo, Jung-Han
    • Steel and Composite Structures
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    • v.14 no.2
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    • pp.133-153
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    • 2013
  • The concrete-filled steel tube (CFT) columns have several benefits of high load-bearing capacity, inherent ductility and toughness because of the confinement effect of the steel tube on concrete and the restraining effect of the concrete on local buckling of steel tube. However, the experimental research into the behavior of square CFT columns consisting of high-strength steel and high-strength concrete is limited. Six full scale CFT specimens were tested under flexural moment. The CFT columns consisted of high-strength steel tubes ($f_y$ = 325 MPa, 555 MPa, 900 MPa) and high-strength concrete ($f_{ck}$ = 80 MPa and 120 MPa). The ultimate capacity of high strength square CFT columns was compared with AISC-LRFD design code. Also, this study was focused on investigating the effect of high-strength materials on the structural behavior and the mathematical models of the steel tube and concrete. Nonlinear fiber element analyses were conducted based on the material model considering the cyclic bending behavior of high-strength CFT members. The results obtained from the numerical analyses were compared with the experimental results. It was found that the numerical analysis results agree well with the experimental results.

Fluid Simulation Control for Effective VFX Underwater Explosion Effects (효과적인 VFX 수중 폭발효과 구현을 위한 유체 시뮬레이션 제어)

  • Hwang, Min Sik;Lee, Hyunseok
    • Journal of Korea Multimedia Society
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    • v.20 no.9
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    • pp.1606-1618
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    • 2017
  • The explosion effect of computer graphics Visual Effects(VFX) used in films and animations is an important element that determines the completeness of the film, and its usage is getting extended. The realistic explosion effect of VFX should be made according to observations and analysis of various factors of actual explosion in real world. This experimental research would suggest the efficient production guideline for the technical characteristics of underwater explosion of VFX. For this research process, first, the comparison of actual explosion and VFX explosion effect, classification of actual explosion, and characteristics of underwater explosion effect will be addressed. Second, based on the literature reviews, the four steps of experimental production analysis tool will be derived. Third, the experimental research will be processed in along with technical factors four steps of the underwater explosion effect, (1)realistic creation and emission of fluid, (2)fluid expansion control by water pressure, (3)bubble effect, and (4)motion of bubble & dissipation of fluid. The effective method of fluid simulation production will be verified through experimental studies based on the characteristics of the actual explosion process. This experimental study suggested the VFX production technique is expected to be used as the basic data for related research field.

Development and evaluation of a pediatric nursing competency-building program for nursing students in South Korea: a quasi-experimental study

  • Koo, Hyun Young;Lee, Bo Ryeong
    • Child Health Nursing Research
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    • v.28 no.3
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    • pp.167-175
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    • 2022
  • Purpose: The present study aimed to develop and examine the effectiveness of a pediatric nursing competency-building program for nursing students. Methods: This was a quasi-experimental study with a nonequivalent control group pretest-posttest design conducted between October and December 2021. The participants included 40 nursing students (20 each in the experimental and control groups) at a university in a South Korean city. The pediatric nursing competency-building program integrated problem-based learning and simulation into clinical field practice. The experimental group participated in the program, while the control group did not. Data were analyzed using the 𝑥2 test, the independent t-test, and repeated-measures analysis of variance. Results: Pediatric nursing competency and clinical performance showed a greater increase in the experimental group than in the control group. However, the change in problem-solving ability in the experimental group was not significantly different from that in the control group. Conclusion: The pediatric nursing competency-building program effectively improved students' pediatric nursing competency and clinical performance.

Numerical simulation of columns with un-bonded reinforcing bars for crack control

  • Chen, G.;Fukuyama, H.;Teshigawara, M.;Etoh, H.;Kusunoki, K.;Suwada, H.
    • Structural Engineering and Mechanics
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    • v.26 no.4
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    • pp.409-426
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    • 2007
  • Following previous work carried out in Building Research Institute in Japan, finite element analyses of conceptual column designs are performed in this paper. The effectiveness of the numerical model is evaluated by experimental tests and parametric studies are conducted to determine influential factors in conceptual column designs. First, three different column designs are analysed: bonded, un-bonded, and un-bonded with additional reinforcing bars. The load-displacement curves and cracking patterns in concrete are obtained and compared with experimental ones. The comparisons indicate that the finite element model is able to reflect the experimental results closely. Both numerical and experimental results show that, the introduction of un-bonded zones in a column end can reduce cracking strains, accordingly reduce the stiffness and strength as well; the addition of extra reinforcement in the un-bonded zones can offset the losses of the stiffness and strength. To decide the proper length of the un-bonded zones and the sufficient amount of the additional reinforcing bars, parametric studies are carried out on their influences. It has been found that the stiffness of un-bonded designs slightly decreases with increasing the length of the un-bonded zones and increases with the size of the additional reinforcing bars.

Effectiveness of using Cognitive Virtual Tours based on Marzano Model to Develop the Achievement and Historical Research Skills for Secondary School Students

  • Abdalla, Atef Mohamed Saied
    • International Journal of Computer Science & Network Security
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    • v.22 no.8
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    • pp.292-298
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    • 2022
  • The study aimed to measure the effectiveness of using Cognitive virtual tours based on Marzano model to develop the achievement and some of historical research Skills for secondary school students. To achieve the objectives of the study, the experimental method was used and two study groups consisted of (60) students were divided into two groups, one is Control (30) students and the other is in experimental (30) students at Alsalam secondary in Ismailia Governorate. The study used several tools: The experimental processing tool of Cognitive Virtual tours based on Marzano model, Cognitive achievement test for the first unit of Secondary first grade history Course. Historical research skills. The finding of the study showed the effectiveness of using cognitive virtual tours based on Marzano model in developing the achievement and some of historical research skills for first grade secondary students which there are Statistically differences at level (0.01) between the average scores of the students in (experimental and Control) groups in post application for Cognitive achievement test. Practical application of the study can contribute to clarify how to use Cognitive virtual tours based on Marzano model in teaching history, and Draw the attention of history developers to the development of historical research skills.

Experimental Studies on the Anti-inflammatory Effect of Cannabis sativa based on a Scientometric Analysis

  • Eunsoo Sohn;Sung Hyeok Kim;Sohee Jang;Se-Hui Jung;Kooyeon Lee;Eun-Hwa Sohn
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2021.04a
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    • pp.45-45
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    • 2021
  • This study aimed to explore research on bibliometric features of cannabis by applying scientometric analysis method, and to approach experimental research evaluation based on it. A total of 30,352 articles on cannabis published since 2001 from SCOPUS were analyzed using KnowledgeMatrix Plus and VOSviewer software. Results showed differences in research activities in countries where cannabis is legalized (Canada, the United States, the Netherlands) and Asian countries where its use is illegal. Related to medical cannabis, there has been a noticeable increase in the number of studies on pain, epilepsy, seizures and brain diseases such as multiple sclerosis. In the field of basic research, the number of pharmacological studies of cannabis on the cannabinoid type 1 receptor signaling pathway and inflammation and obesity has increased significantly. Subsequent experimental studies have compared the anti-inflammatory effects of four parts of Korean cannabis such as root, stem, leaf, and bark. Consistent with the predicted results of the scientometric analysis, all parts of C. sativa showed inhibitory effects on COX-2, NO/iNOS and TNF-α expression in LPS-stimulated RAW264.7 cells. These attempts provide an experimental research approach based on scientometric assessment.

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Effect of Radioisotope Position on Performance of Industrial SPECT (방사성동위원소 위치에 따른 산업용 SPECT 성능에 미치는 영향)

  • Moon, Jinho;Kim, Jongbum;Jung, Sung-Hee
    • Journal of Radiation Industry
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    • v.6 no.3
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    • pp.245-249
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    • 2012
  • Demand of fluid flow visualization has increased in industrial processes, because medical imaging technology is highly developed. As a part of the industrial process imaging technology, industrial single photon emission computed tomography (SPECT) system was developed to measure the cross-sectional distribution of the process fluid. The SPECT consists of 36 NaI (Tl) detectors with the hexagonal configuration. Reconstructed images were acquired for various positions of radioactive source to estimate SPECT device performance. To evaluate the reliability of the experimental results, the Monte Carlo simulation results are compared with experimental results. In general, the experimental and simulation results were consistent. However, as the source position was getting far from the center of the reactor, the accuracy of reconstructed images was compromised. It seems to be due to the inconsistent spatial resolution of the collimators according to the source position.

Stability, Efficacy, Absorption and Toxicity of a New Nasal Spray Formulation including Salmon Calcitonin

  • Shim, Hyun-Joo;Kim, Mi-Kyung;Bae, En-Joo;Lee, Eung-Doo;Hyun Jo;Kim, Soon-Hae;Kwon, Jong-Won;Kim, Won-Bae
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1998.11a
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    • pp.137-137
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    • 1998
  • Stability, efficacy, absorption and toxicity of a new nasal spray formulation including salmon calcitonin were studied in the laboratory animals. After the effects of many excipients on the stability of salmon calcitonin were evaluated using HPLC system, we selected taurine. Our experimental composition of salmon calcitonin contains taurine as a stabilizer and HPMC (hydroxypropylmethyl cellulose) as an adhesive polymer. After intranasal administration of salmon calcitonin formulations, Mia$\^$(R)/, Men$\^$(R)/ and experimental composition, 22 IU to rats, the reduction percentages of calcium concentration in plasma (ΔD%) were 16.3%, 12.9% and 20.8%, respectively. After intranasal administration of Mia$\^$(R)/, Men$\^$(R)/ and experimental composition to rats, C$\sub$MAX/ (205${\pm}$161, 244${\pm}$117, and 330${\pm}$202 pg/$m\ell$, respectively) and AUC (41585${\pm}$22070, 41191${\pm}$19125, and 63357${\pm}$43126 pg. min/$m\ell$, respectively) were calculated. The permeation coefficients 10$\^$-7/,cm/sec) of salmon calcitonin in Mia$\^$(R)/, Men$\^$(R)/ and experimental composition using Ussing chamber with rabbit nasal mucosa were 4.7${\pm}$1.5, 0.75${\pm}$0.4 and 5.3${\pm}$1.1, respectively. The experimental composition with taurine and HPMC was proved to be excellent because it improved the stability of salmon calcitonin and inhanced the absorption of salmon calcitonin and was not irritative to the nasal mucosa.

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A study on the Allegory and Experimental presentation technique in Film by Zbigniew Rybczynski (Zbigniew Rybczynski 영상의 실험적 표현기법과 알레고리에 관한 연구)

  • Kim, Yun-Kyung
    • Cartoon and Animation Studies
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    • s.34
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    • pp.1-22
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    • 2014
  • The purpose of this research is to study a case of allegory and experimental presentation technique in Film by Zbigniew Rybczynski. It is to analyse this study is to inquire into the fact that experimental animation carries diverse interpretation of comtemporary art and the purpose of this study is to identify certain style through the interpretation of allegory focused on film Tango which has expanded the field of experimental animation with the unique form of the film structure and technique. Therefore, in this research, I would highlight the characteristic of allegory in Film by Zbigniew Rybczynski and research the experimental presentation technique that appears in experimental animation focused on "fragmentation" which are the expressive style of allegory.

EFFECTS OF CHRONIC INGESTION OF ANTHRANILIC ACID ON MAMMARY GLAND GROWTH IN SHN MICE

  • Nagasawa, H.;Konishi, R.;Sakagami, N.;Inatomi, H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.1 no.3
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    • pp.139-142
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    • 1988
  • Effects of anthranilic acid on normal mammary gland growth were examined in SHN/Mei female virgin mice. Anthranilic acid was given to the experimental groups as drinking water at the concentrations of 0.01, 0.02 or 0.04% for 21 days beginning 2-3 months of age. The control group received tap water only. RNA content and RNA/DNA ratio in mammary glands were significantly higher in mice given 0.04% anthranilic acid than in the control, while not mammary DNA content. The results indicate that chronic ingestion of anthranilic acid can induce an enhancement of proliferation and differentiation of mammary cells.