• Title/Summary/Keyword: combination tests

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A Study on the Characteristics of the Tube-to-Support Dynamic Impact Force Measurement Facility (튜브와 지지대 사이의 동적상호 충격력 측정장치 특성규명에 관한 연구)

  • 김일곤;박진무
    • Journal of KSNVE
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    • v.5 no.1
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    • pp.95-106
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    • 1995
  • Flow-induced vibration in heat exchanger (or fuel rod) in nuclar power plant can cause dynamic interactions between tubes and tube supports resulting in fretting-wear. To increase the reliability and design life of heat exchanger components, design criteria that establish acceptable limits of vibration and minimize fretting wear are necessary. The fretting-wear rate is dependent upon material combination, contact configuration, environmental conditions and tube-to tube support dynamic interaction. It is demostrated that the fretting -wear rate correlates well with tube-to-support contact force or work rate. The tube-to-support dynamic interaction, which consists of dynamic contact forces and tube motion, is used to relate single-span wear data to real heat exchanger configurations consisting of multi-span tube bundles. This paper describes the test facility to measure tube-to-support dynamic impact force and reports its dynamic characteristics through the four impact tests - a force transduces independent and external impact tests, central ring inside impact test and additional cylinder impact test. Through the tests the impact parameter change dependent upon the material difference of impacting ball is studied, and the impact parameters of Force Transducer Assembly components are measured. And also the dynamic behavior of Force Transducer Assembly is analyzed. The force measurement technique herein is shown to provide a reasonable measure of dynamic contact forces.

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Correlation of single leg vertical jump, single leg hop, and single leg squat distances in healthy persons

  • Shin, Seung-Ho;Woo, Hyunjae
    • Physical Therapy Rehabilitation Science
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    • v.2 no.1
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    • pp.57-61
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    • 2013
  • Objective: To determine the correlation among three functional tests: single leg vertical jump (SLVJ), single leg hop for distance (SLHD), and single leg squat (SLSQ). Design: Cross sectional study. Methods: Twenty healthy men (n=10) and women (n=10) with no history of lower extremity dysfucntion participated in this study and performed in university research laboratory. The procedures consisted of a general warm-up, a task-specific warm-up, actual testing, and a cool down. All participants performed the three tests in random order. Each test was performed three times for the dominant and non-dominant lower extremity (LE). SLVJ, SLHD, SLSQ were measured using a standard tape measure. Results: Statistically significant difference was presented between dominant LE and non-dominant LE in each function test (p<0.05). The strongest correlation was between SLVJ and SLSQ, 0.939 and 0.883 for dominant and non-dominant LE, respectively (p<0.05). The weakest correlation was between SLVJ and SLHD, 0.713 for dominant (p<0.05) and between SLSQ and SLHD, 0.739 for non-dominant (p<0.05). Conclusions: There is a strong correlation between SLVJ and SLSQ, suggesting that each test measures similar constructs of function and can be substitutive, while weak correlation between SLSQ and SLHD suggest these two tests do not measure the same functional components and could be paired as outcome measures for the clinical assessment of LE function. It will provide physical therapist with scientific evidence for effective test combination of LE function assessment in clinical practice.

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A tutorial on generalizing the default Bayesian t-test via posterior sampling and encompassing priors

  • Faulkenberry, Thomas J.
    • Communications for Statistical Applications and Methods
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    • v.26 no.2
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    • pp.217-238
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    • 2019
  • With the advent of so-called "default" Bayesian hypothesis tests, scientists in applied fields have gained access to a powerful and principled method for testing hypotheses. However, such default tests usually come with a compromise, requiring the analyst to accept a one-size-fits-all approach to hypothesis testing. Further, such tests may not have the flexibility to test problems the scientist really cares about. In this tutorial, I demonstrate a flexible approach to generalizing one specific default test (the JZS t-test) (Rouder et al., Psychonomic Bulletin & Review, 16, 225-237, 2009) that is becoming increasingly popular in the social and behavioral sciences. The approach uses two results, the Savage-Dickey density ratio (Dickey and Lientz, 1980) and the technique of encompassing priors (Klugkist et al., Statistica Neerlandica, 59, 57-69, 2005) in combination with MCMC sampling via an easy-to-use probabilistic modeling package for R called Greta. Through a comprehensive mathematical description of the techniques as well as illustrative examples, the reader is presented with a general, flexible workflow that can be extended to solve problems relevant to his or her own work.

The Effect of CPR Clinical Training in Nursing Students's Knowledge and Practical Ability (심폐소생술 실습교육이 간호학생의 지식 및 수행능력에 미치는 효과)

  • Oh, Suk-Hee;Sun, Jung-Joo;Kim, Sang-Hee
    • Journal of Korean Public Health Nursing
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    • v.23 no.2
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    • pp.153-161
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    • 2009
  • Purpose: This study was done to evaluate the differences between an experimental group and a control group of nursing students for their knowledge of CPR and their practical ability after undergoing CPR training. Method: This experiment was done with nursing students, who are divided into the experimental group (20 students) and the control group (23 students) in Chunbuk C city. The data were analyzed using the SPSS PC+ 12.0 program for the Chi-square tests, t-tests and Wilcoxon rank sum tests. Results: The 1st hypothesis, that the CPR knowledge scores for the experimental group will be higher than the scores for the control group (t=-3.934, p=<.001), was supported. On the other hand, the control group showed a conspicuous and meaningful improvement (t=-3.932, p=<.001). The 2st hypothesis, that the practical ability scores for the experimental group will be higher than the scores for the control group (t=-3.926, p=<.001), was supported. Conclusion: The CPR training in combination with theory and clinical placement is seen as a means to effectively develop the knowledge and practical ability of CPR.

Investigating the combination of natural and crushed gravel on the fresh and hardened properties of self-compacting concrete

  • Moosa Mazloom;Mohammad Ebrahim Charmsazi;Mohammad Hosein Parhizkari
    • Structural Monitoring and Maintenance
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    • v.11 no.1
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    • pp.1-18
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    • 2024
  • Self-compacting concrete is widely used around the globe today due to its special and unique properties. This study examines the effect of natural and crushed gravel combinations in different percentages in short-and long-term properties of concrete. The best utilized sand had a fineness modulus of 2.7. In the mentioned mix designs, silica fume was used with 0 and 7% of the weight of the cement. In order to check the properties of fresh and hardened concrete, 9 and 5 test types were performed, respectively. The carried out tests were slump flow, V-funnel, J-ring, L-box, U-box and column segregation for fresh concrete, and compressive, tensile and flexural strengths for hardened concrete. A mix with only 100% natural gravel was considered as the control mix. According to the results, the control mix design and the one containing 100% crushed gravel with silica fume were the best in fresh and hardened concrete tests, respectively. Finally, using the optimization method, a mix design with 25% natural gravel, 75% crushed gravel and silica fume was introduced as the best mix in terms of the results of both fresh and hardened concrete tests.

Efficacy of Pap Test in Combination with ThinPrep Cytological Test in Screening for Cervical Cancer

  • Chen, Hua;Shu, Hui-Min;Chang, Zhou-Lin;Wang, Zhi-Feng;Yao, Hai-Hong;Zhu, Hong-Mei;Lu, Tian-Mei;Ma, Qiang-Yan;Yang, Bin-Lie
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.4
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    • pp.1651-1655
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    • 2012
  • Background: Our aim was to investigate the efficacy of the Pap test in combination with the ThinPrep cytological test (TCT) in screening for cervical cancer in China. Design: From March 2006 to October 2008, 988 women with the mean age $46.4{\pm}10.5$ years (range, 23-80 years) were recruited to receive cervical cancer screening. Pap test results ${\geq}$ grade III and TCT findings ${\geq}$ ASCUS/AGUS were considered abnormal. Subjects with a Pap test result ${\geq}$ grade IIb received TCT. Colposcopy and biopsies were performed in all participants, and final diagnosis was based on pathological findings. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and Youden index for predicting CIN I or above were determined. Results: The sensitivity, specificity, PPV, NPV and Youden index of the Pap test were 43.1%, 97.2%, 70.0%, 91.9%, and 40.3%, respectively. The same values for TCT in predicting CIN were 80.0%, 63.2%, 16.0%, 97.3%, and 43.2%, respectively. The two tests in combination gave values for predicting CIN of 64.8%, 87.6%, 43.6%, 94.4%, and 53.5%, respectively. Combined testing exhibited the highest Youden index (53.4%). Conclusion: The Pap test with a reduced threshold in combination with the TCT has high sensitivity and high specificity in screening for cervical cancer.

Slope stabilization with high-performance steel wire meshes in combination with nails and anchors

  • Rudolf Ruegger;Daniel Flum
    • Proceedings of the Korean Geotechical Society Conference
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    • 2000.11b
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    • pp.3-38
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    • 2000
  • Slope draperies in soil and rock are a well known method to avoid rockfalls into the roads or onto housings. Common wire mesh or a combination of wire mesh and wire rope nets are pinned to the slope by the means of fully grouted nails or anchors. Most of these installations have not been designed to stabilize the slope, but simply avoid the rocks from bouncing. The combination of soil- or rocknailing with a designable flexible facing system offers the advantage of a longterm stabilization of slopes and can replace other standard methods for slope stabilization. The capability to transfer axial and shear loads from the flexible facing system to the anchor points is most decisive for the design of the stabilization system. But the transfer of forces by mesh as pure surface protection devices is limited on account of their tensile strength and above all also by the possible force transmission to the anchoring points. Strong wire rope nets increase the performance for slope stabilizations with greater distances between nails and anchors and are widely used in Europe. However, they are comparatively expensive in relation to the protected surface. Today, special processes enable the production of diagonally structured mesh from high-tensile steel wire. These mesh provide tensile strengths comparable to wire rope nets. The interaction of mesh and fastening to nail / anchor has been investigated in comprehensive laboratory tests. This also in an effort to find a suitable fastening plates which allows an optimal utilization of the strength of the mesh in tangential (slope-parallel) as well as in vertical direction (perpendicular to the slope). The trials also confirmed that these new mesh, in combination with suitable plates, enable substantial pretensioning of the system. Such pretensioning increases the efficiency of the protection system. This restricts deformations in the surface section of critical slopes which might otherwise cause slides and movements as a result of dilatation. Suitable dimensioning models permit to correctly dimension such systems. The new mesh with the adapted fastening elements have already been installed in first pilot projects in Switzerland and Germany and provide useful information on handling and effects.

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Improvement of Biocontrol of Damping-off and Root Rot/Wilt of Faba Bean by Salicylic Acid and Hydrogen Peroxide

  • Abdel-Monaim, Montaser Fawzy
    • Mycobiology
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    • v.41 no.1
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    • pp.47-55
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    • 2013
  • Rhizoctonia solani, Fusarium solani, F. oxysporum, and Macrophomina phaseolina were found to be associated with root rott and wilt symptoms of faba bean plants collected from different fieldes in New Valley governorate, Egypt. All the obtained isolates were able to attack faba bean plants (cv. Giza 40) causing damping-off and root rot/wilt diseases. R. solani isolates 2 and 5, F. solani isolate 8, F. oxysporum isolate 12 and M. phaseolina isolate 14 were the more virulent ones in the pathogenicity tests. Biocontrol agents (Trichoderma viride and Bacillus megaterium) and chemical inducers (salicylic acid [SA] and hydrogen peroxide) individually or in combination were examined for biological control of damping-off and root rot/wilt and growth promoting of faba bean plants in vitro and in vivo. Both antagonistic biocontrol agents and chemical inducers either individually or in combination inhibited growth of the tested pathogenic fungi. Biocontrol agents combined with chemical inducers recorded the highest inhibited growth especially in case SA + T. viride and SA + B. megaterium. Under green house and field conditions, all treatments significantly reduced damping-off and root rot/wilt severity and increased of survival plants. Also, these treatments increased fresh and weights of the survival plants in pots compared with control. The combination between biocontrol agents and chemical inducers were more effective than used of them individually and SA + T. viride was the best treatment in this respect. Also, under field conditions, all these treatments significantly increased growth parameters (plant height and number of branches per plant) and yield components (number of pods per plant and number of seeds per plant, weight of 100 seeds and total yield per feddan) and protein content in both seasons (2010~2011 and 2011~2012). Faba bean seeds soaked in SA + T. viride and SA + B. megaterium were recorded the highest growth parameters and yield components. Generally, the combination between biocontrol agents and chemical inducers recorded the best results for controlling damping-off and root rot/wilt diseases in greenhouse and field with addition improved plant growth and increased yield components in field.

Studies on the Control of Bud Bright of Mulberry Tree when Intermediate-Cutting Harvest in Autumn (추기 중간벌채수확 뽕나무의 아고병방제에 관할 연구)

  • 유근섭
    • Journal of Sericultural and Entomological Science
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    • v.16 no.2
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    • pp.99-109
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    • 1974
  • These studies aimed to establishment of controlling measure of the bud blight of mulberry tree when intermediate cutting harvest in autumn. The results obtained as following. 1. Effect of chemicals a) Results of 1972 (1) Of the seventeen chemicals tested. according to in vitro, the mycelial growth of Gibberella lateritium f. sp. mori was highly inhibited by PTAB and Benlate. PTAB and Benlate were also highly effective under the conditions of pathogen inoculated to the piece of mulberry tree and fungicidal action of these chemicals were stronger than the others. (2) Topsin-M. organic fungicide and plant growth regulator were not effective to inhibition of mycelial growth. (3) The effectiveness of fungicides were reduced gradually as the time after treatment increased. PTAB and Benlate retained approximately 50 percent of the original activity even after 15 days. (t) Of the twelve chemicals tested in fold, Benlate combination of PTAB with Apion, Apion and PTAB were the most effective fungicides for the control of bud blight of mulberry tree. (5) There is a sigificant difference between the timing on spraying, but it is not greatly effective for the control of bud blight of mulberry tree. b) Results of 1975 (1) Of the ten chemicals tested, according to in vitro RH 893, combination of Benlate with TMTD and TMTD were the most effective to inhibition of mycelial growth, followed by Benlate and combination of Benlate with Topsin M. (2) Of the eleven chemicals tested, Benlate, combination of Benlate with Kinondu, combination of Benlate with Topsin-M and Topsin M were highly effective under the renditions of pathogen inoculated to the piece of mulberry tree. (3) Of the eleven chemical evaluation tests were conducted in 3 experiment fold of Seoul, Chuncheun and Pusan, Benlate, Topsin-M, Apion, TMTD. combination of Benlate with Topsin-M, combination of Benlate with TMTD, combination of Benlate with Apion were highly effective chemicals for the control of bud blight of mulberry tree. (4) There is no difference between the timing on the chemical spraying after intermediate cutting harvest mulberry tree in autumn. 2. Ecological Control. When the mulberry shoot were cut off one to two buds from the top of intermediate cutting from 15th to 30th on October, bud blight of mulberry tree was greatly reduced in next spring compared with the effective chemical spraying. 3. Economical analysis on the results of chemical and ecological tests. When the expenses of ecological control for bud blight of mulberry tree per one ha was 100. thats of chemical control was from 159 to 254 according to spraying machines.

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Thermal-Mechanical and Low Cycle Fatigue Characteristics of 12Cr Heat Resisting Steel with Hold Time Effects (유지시간 효과를 고려한 12Cr 내열강의 열피로 및 저주기 피로 특성)

  • Ha, J.S.;Koh, S.K.;Ong, J.W.
    • Transactions of the Korean Society of Automotive Engineers
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    • v.3 no.1
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    • pp.1-12
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    • 1995
  • Isothermal and thermal-mechanical fatigue characteristics of 12Cr heat resisting steel used for high temperature applications were investigated including hold time effects. Isothermal low cycle fatigue test at $600^{\circ}C$ and in-phase, out-of-phase thermal-mechanical fatigue test at 350 to $600^{\circ}C$ were conducted using smooth cylindrical hollow specimen under strain-control with total strain ranges from 0.006 to 0.015. Regardless of thermal-mechanical and isothermal fatigue tests, cyclic softening behavior was observed and much more pronounced in the thermal-mechanical fatigue tests with hold times due to the stress relaxation during the hold time. The phase difference between temperature and strain in thermal-mechanical fatigue tests resulted in significantly shorter fatigue life for out-of-phase compared to in-phase. The differences in fatigue lives were dependent upon the magnitudes of plastic strain ranges and mean stresses. During the hold time in the strain-controlled fatigue tests, the increase in the plastic strain range and the stress relaxation were observed. It appeared that the increase in plastic strain range per cycle and the introduction of creep damage made important contributions to the reduction of thermal-mechanical fatigue life with hold time, and the life reduction tendency was more remarkable in the in-phase than in the out-of-phase thermal-mechanical fatigue. Isothermal fatigue tests performed under the combination of fast and slow strain rates at $600^{\circ}C$ showed that the fatigue life decreased as the strain rate and frequency decreased,especially for the low strain ranges.

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