scholarly journals Characteristic Value of the Modulus of Elasticity (MOE) for Natural and Planted Larch in Northeast China

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 883
Author(s):  
Zhaopeng Tian ◽  
Junhua Xu ◽  
Mingyue Li ◽  
Zhaohui Wang ◽  
Erik Serrano ◽  
...  
Keyword(s):  
Modulus Of Elasticity ◽  
Northeast China ◽  
Parametric Method ◽  
Measured Data ◽  
Distribution Model ◽  
Characteristic Value ◽  
Dimension Lumber ◽  
Density Values ◽  
Characteristic Values ◽  
The Difference

The density and modulus of elasticity (MOE) distribution can provide information on the effectiveness of parametric and non-parametric methods in calculating the characteristic value of MOE. In this study, we aim to determine the optimal distribution model of the actual measured data of the lumber. We also estimate the lumber’s MOE characteristic value and compare the difference in density and MOE between natural and planted larch. Approximately 1200 pieces of dimension lumber of 4 m × 140 mm × 40 mm in size, made from larch and planted larch, were obtained, tested, and the corresponding standard MOE value was calculated. Results revealed the 3-parameter Weibull distribution to be optimal in fitting the natural and planted larch distributions. The parametric method proved effective in calculating the characteristic value of both larch groups, with characteristic MOE values of 9.73 kN/mm2 and 8.84 kN/mm2, and characteristic density values of 530 kg/m3 and 460 kg/m3 for natural and planted larch, respectively. Moreover, the MOE and density values followed grades C40 and C35. Thus, the conclusion is that the parametric method should be used to determine these characteristic values for natural and planted larch.

Pengaruh Tekanan dan Penggunaan Conplast terhadap Sifat Mekanik Eternit dari Abu Cangkang Sawit

2016 ◽  
Vol 8 (15) ◽  
pp. 47-54
Author(s):  
Haspiadi Haspiadi
Keyword(s):  
Mechanical Properties ◽  
Oil Palm ◽  
Modulus Of Elasticity ◽  
Modulus Of Rupture ◽  
Palm Shell ◽  
Oil Palm Shell ◽  
Density Values ◽  
Test Result

The purpose of this research is to know the influence of pressure and use of conplast against mechanical properties which are a Modulus of Elasticity (MOE) and Modulus of Rupture (MOR) of plasterboard. The study is done because still low quality of plasterboard made from a mixture of ashes of oil-palm shell especially of the mechanical properties compared to the controls. The method of this reserach used variation of printed pressure and the addition of conplast. Test result is obtained that the highest value of Modulus of Elasticity (MOE) 90875.94 Kg/cm2, Modulus of Rupture (MOR) 61.16 Kg/cm2 and density values in generally good printed at the pressure 60 g/cm3 and the addition of conplast 25% as well as the composition of the ash of palm shell oil 40%: limestone 40%: cement 15%: fiber 5% and 300 mL of water. ABSTRAK Tujuan dari penelitian ini adalah untuk mengetahui pengaruh tekanan dan penggunaan conplast terhadap sifat mekanik yaitu kuat lentur dan keteguhan patah eternit berbahan dasar abu cangkang sawit. Penelitian ini dilakukan karena masi rendahnya mutu eternit berbahan campuran abu cangkang sawit dari bolier khususnya sifat mekanik dibandingkan dengan kontrol. Metode penelitian yang digunakan adalah dengan variasi tekanan cetak dan penambahan conplast. Hasil uji diperoleh bahwa kuat lentur tertinggi sebesar 90875,94 Kg/cm2 dan keteguhan patah sebesar 61,16 Kg/cm2, yang dicetak pada tekanan 60 g/cm3 dan penambahan conplast 25% dengan komposisi  abu cangkang sawit 40 %: kapur 40 % : semen 15 %: serat 5 % dan air 300 mL.Kata Kunci :  Abu cangkang sawit, conplast, kuat lentur, keteguhan patah.

scholarly journals Preliminary evaluation for quality of dimension lumber in four common softwoods in Mongolia

2020 ◽  
Vol 66 (1) ◽  
Author(s):  
Murzabyek Sarkhad ◽  
Futoshi Ishiguri ◽  
Ikumi Nezu ◽  
Bayasaa Tumenjargal ◽  
Yusuke Takahashi ◽  
...  
Keyword(s):  
Pinus Sylvestris ◽  
Modulus Of Rupture ◽  
Preliminary Evaluation ◽  
Pinus Sibirica ◽  
Bending Properties ◽  
Picea Obovata ◽  
Dimension Lumber ◽  
Commercial Species ◽  
Characteristic Values

Abstract The quality of dimension lumber (2 by 4 lumber) was preliminarily investigated in four common Mongolian softwoods: Pinus sylvestris L., Pinus sibirica Du Tour, Picea obovata Ledeb., and Larix sibirica Ledeb. to produce high quality dimension lumber for structural use. In total 61, 39, 67, and 37 pieces of lumber were prepared for Pinus sylvestris, Pinus sibirica, Picea obovata, and L. sibirica, respectively. The lumber was visually graded and then tested in static bending to obtain the 5% lower tolerance limits at 75% confidence level (f0.05) of the modulus of elasticity (MOE) and the modulus of rupture (MOR). In addition, the effects of sawing patterns on bending properties were also analyzed. The f0.05 of the MOE and MOR were 4.75 GPa and 15.6 MPa, 3.39 GPa and 11.0 MPa, 3.78 GPa and 11.7 MPa, and 6.07 GPa and 22.3 MPa for Pinus sylvestris, Pinus sibirica, Picea obovata, and L. sibirica, respectively. These results suggested that with a few exceptions, characteristic values of MOR in the four common Mongolian softwoods resembled those in similar commercial species already used. In visual grading, over 80% of total lumber was assigned to select structural and No. 1 grades in Pinus sylvestris and Pinus sibirica, whereas approximately 40% of total lumber in L. sibirica was No. 3 and out of grades. Sawing patterns affected bending properties in Pinus sylvestris and L. sibirica, but did not affect Pinus sibirica and Picea obovata. Dynamic Young's modulus was significantly correlated with bending properties of dimension lumber for the four species. Based on the results, it was concluded that dimension lumber for structural use can be produced from the four common Mongolian softwoods.

The feasibility and validity of using a real time location system (RTLS) to measure bedside contact time

2021 ◽  
pp. 174498712110161
Author(s):  
Ann-Marie Cannaby ◽  
Vanda Carter ◽  
Thomas Hoe ◽  
Stephenson Strobel ◽  
Elena Ashtari Tafti ◽  
...  
Keyword(s):  
Real Time ◽  
Contact Time ◽  
Measured Data ◽  
Complete Agreement ◽  
Observation Data ◽  
The Real ◽  
Measured Time ◽  
The Difference ◽  
Hospital Wards ◽  
Location Systems

Background The association between the nurse-to-patient ratio and patient outcomes has been extensively investigated. Real time location systems have the potential capability of measuring the actual amount of bedside contact patients receive. Aims This study aimed to determine the feasibility and accuracy of real time location systems as a measure of the amount of contact time that nurses spent in the patients’ bed space. Methods An exploratory, observational, feasibility study was designed to compare the accuracy of data collection between manual observation performed by a researcher and real time location systems data capture capability. Four nurses participated in the study, which took place in 2019 on two hospital wards. They were observed by a researcher while carrying out their work activities for a total of 230 minutes. The amount of time the nurses spent in the patients’ bed space was recorded in 10-minute blocks of time and the real time location systems data were extracted for the same nurse at the time of observation. Data were then analysed for the level of agreement between the observed and the real time location systems measured data, descriptively and graphically using a kernel density and a scatter plot. Results The difference (in minutes) between researcher observed and real time location systems measured data for the 23, 10-minute observation blocks ranged from zero (complete agreement) to 5 minutes. The mean difference between the researcher observed and real time location systems time in the patients’ bed space was one minute (10% of the time). On average, real time location systems measured time in the bed space was longer than the researcher observed time. Conclusions There were good levels of agreement between researcher observation and real time location systems data of the time nurses spend at the bedside. This study confirms that it is feasible to use real time location systems as an accurate measure of the amount of time nurses spend at the patients’ bedside.

Degradation Screening Test Design for Electronic Products

2010 ◽  
Vol 156-157 ◽  
pp. 747-753
Author(s):  
Rui Lin Lin ◽  
Qiang Hui Zhong
Keyword(s):  
Screening Test ◽  
Performance Characteristics ◽  
Screening Tests ◽  
Distribution Model ◽  
Test Design ◽  
Aging Effects ◽  
Electronic Products ◽  
Model Coefficient ◽  
Degradation Characteristic ◽  
The Difference

Long-life electronic products need to be put in stress environment for long durations in traditional ESS(environmental stress screening) tests in order that items having infant mortality or defects are weeded out from products. However, long stress durations cause aging effects on good items. For some products, failures are defined in terms of performance characteristics degrading some critical values. For the purpose of reducing durations and aging effects, this paper analyzes the difference of performance characteristics between normally degraded products and abnormally degraded products, and assumes the distribution of products’ degradation characteristic variable is contaminated distribution model, then presents a degradation screening test design. This design firstly ascertains the model coefficient using identifiable condition of contaminated distribution combined with the analysis of degradation test, then ascertains screen duration and screen critical value. Lastly, this paper gives an example to illustrate the availability of the design.

scholarly journals Analysis and Development of Seawater Density Measurement Algorithms Using Arduino Uno and YL-69 Sensor

2020 ◽  
Vol 4 (5) ◽  
pp. 951-956
Author(s):  
Miftahul Walid ◽  
Hozairi ◽  
Madukil Makruf
Keyword(s):  
Sea Water ◽  
Density Measurement ◽  
Absolute Error ◽  
Error Level ◽  
Value Range ◽  
Density Values ◽  
The Mean ◽  
Arduino Uno ◽  
The Difference ◽  
Predicted Values

In this research, an analysis was carried out to develop a measuring instrument for seawater density in salt production using a microcontroller (Arduino Uno) and YL-69 sensor, this sensor was commonly used to measure soil moisture. The experimental method was used in this research to produce initial data in the form of resistance and seawater density values, then calculations are carried out using statistical methods to find equations and produce a constant variable that connects the resistance and seawater density values. The equation was used to compile the algorithm into Arduino Uno. As for the results of this research,  From six experiments conducted, two experiments produced the same sea water density value between the actual and the predicted, namely the 2nd and 5th experiments, while for other experiments there was a difference between the actual and predicted values, however, it was not too significant, the difference occurs between the value range 0 ~ 1, to determine the level of error, use the Mean Square Error (MSE) with an error level of = 0.5 and Mean Absolute Error (MAE) with an error level of = 0.6. The contribution of this research is an algorithm that can predict the density value (baume) based on the resistance value obtained from the YL 69 sensor.

scholarly journals MICRO-MECHANICAL PROPERTIES OF CEMENT AND SLAG COMPOSITES MEASURED BY NANOINDENTATION

2020 ◽  
Vol 26 ◽  
pp. 45-49
Author(s):  
Jiří Němeček ◽  
Jiří Němeček
Keyword(s):  
Mechanical Properties ◽  
Portland Cement ◽  
Modulus Of Elasticity ◽  
Volume Fraction ◽  
Blended Cement ◽  
Hydration Products ◽  
Granulated Blast Furnace Slag ◽  
The Difference ◽  
Portland Cement Paste ◽  
Furnace Slag

In this study, the micromechanical response of two cementitious composites was characterized by nanoindentation. Pure Portland cement paste and Portland cement with 50 vol. % replaced with granulated blast furnace slag (GBFS) paste were investigated at the age of 28 days. Grid nanoindentation, statistical deconvolution and scanning electron microscopy were used to characterize the main hydration products. Several grids with approximately 500 indents on each sample were performed to obtain modulus of elasticity, hardness and creep indentation parameter. Similar mechanical phases containing calcium silica hydrate, crystalline calcium hydroxide and un-hydrated clinker were found in both samples varying by volume fraction. Blended cement, moreover, contains a phase of slag hydration products with a significantly lower modulus of elasticity. This phase with a high portion of unreacted GBFS is mostly responsible for the difference of mechanical properties of the whole composite.

scholarly journals Case Report. Prosthetic Rehabilitation of Crowded Maxillary Anterior Teeth

2017 ◽  
Vol 2 (s1) ◽  
pp. 64-67
Author(s):  
Emese Rita Markovics ◽  
Kinga Dörner ◽  
Orsolya Birta ◽  
Julia Popa
Keyword(s):  
Case Report ◽  
Plaster Cast ◽  
Point Of View ◽  
Case Presentation ◽  
Golden Proportion ◽  
Anterior Teeth ◽  
Characteristic Values ◽  
The Difference ◽  
Objective Basis ◽  
Dental Plaster

Introduction In this case report we present the aesthetical correction of crowded anterior teeth in a patient who has refused the orthodontic treatment. We also discuss how this correction can be resolved from the point of view of dental prosthetic and what measurements can be helpful in order to collect the data used to restore a satisfying smile on the patient’s face using dental ceramic restoration. Case presentation: A 32-year-old patient complained about his crowded incisors. We examined the incisal curvature, the proportion between the height and the width of the teeth, and the relation between the widths of the teeth and the golden proportion. The results of the measurements were compared to the characteristic values of the ideal denture. After the examination of the dental plaster cast, calculating the difference between the existing space and the necessary space, we were able to calculate the lack of space, which caused the crowded teeth. Conclusion: Along the prosthetic planning, these measurements may serve as a guideline to the dentist as an objective basis for the formation of an aesthetic denture and smile.

scholarly journals A Novel Change Detection Method Based on Statistical Distribution Characteristics Using Multi-Temporal PolSAR Data

Sensors ◽  
2020 ◽  
Vol 20 (5) ◽  
pp. 1508 ◽  
Author(s):  
Jinqi Zhao ◽  
Yonglei Chang ◽  
Jie Yang ◽  
Yufen Niu ◽  
Zhong Lu ◽  
...  
Keyword(s):  
Change Detection ◽  
Optimal Threshold ◽  
Distribution Model ◽  
Test Statistic ◽  
Omnibus Test ◽  
Polarimetric Synthetic Aperture Radar ◽  
Difference Image ◽  
East Lake ◽  
Multi Temporal ◽  
The Difference

Unsupervised change detection approaches, which are relatively straightforward and easy to implement and interpret, and which require no human intervention, are widely used in change detection. Polarimetric synthetic aperture radar (PolSAR), which has an all-weather response capability with increased polarimetric information, is a key tool for change detection. However, for PolSAR data, inadequate evaluation of the difference image (DI) map makes the threshold-based algorithms incompatible with the true distribution model, which causes the change detection results to be ineffective and inaccurate. In this paper, to solve these problems, we focus on the generation of the DI map and the selection of the optimal threshold. An omnibus test statistic is used to generate the DI map from multi-temporal PolSAR images, and an improved Kittler and Illingworth algorithm based on either Weibull or gamma distribution is used to obtain the optimal threshold for generating the change detection map. Multi-temporal PolSAR data obtained by the Radarsat-2 sensor over Wuhan in China are used to verify the efficiency of the proposed method. The experimental results using our approach obtained the best performance in East Lake and Yanxi Lake regions with false alarm rates of 1.59% and 1.80%, total errors of 2.73% and 4.33%, overall accuracy of 97.27% and 95.67%, and Kappa coefficients of 0.6486 and 0.6275, respectively. Our results demonstrated that the proposed method is more suitable than the other compared methods for multi-temporal PolSAR data, and it can obtain both effective and accurate results.

scholarly journals The influence of an applied standard test method on a measurement of concrete stabilized secant modulus of elasticity

2018 ◽  
Vol 163 ◽  
pp. 07001
Author(s):  
Lucyna Domagała ◽  
Justyna Dobrowolska
Keyword(s):  
Modulus Of Elasticity ◽  
Lightweight Aggregate ◽  
Standard Test ◽  
Normal Weight ◽  
Test Method ◽  
Hardened Concrete ◽  
Secant Modulus ◽  
Testing Procedures ◽  
Standard Test Method ◽  
The Difference

The paper focuses on the influence of the standard test method applied to determine the concrete stabilized secant modulus on a specified value. The new European Standard EN 12390-13 for testing hardened concrete accepts two methods (A and B) for the determination of the secant modulus of elasticity in compression. The aim of the research was to establish how different testing procedures affect a measured value of modulus of elasticity. Four structural concrete series: two lightweight aggregate concretes and two normal-weight ones were subject to tests of moduli of elasticity determined by both standard methods, as well as compressive strength and density. The carried out tests revealed that the procedure of testing modulus of elasticity influenced a measured value. Method A led to higher values of modulus in relation to Method B, irrespective of concrete density and strength. Nevertheless, a certain relationship between the concrete structure homogeneity and the difference in results of moduli determined by both methods may be observed.

The Influence of Measured Trajectory Based Model Parameters Correcting on Simulation Precision of Power System Dynamic Frequency

2013 ◽  
Vol 448-453 ◽  
pp. 2545-2550
Author(s):  
Gang Mu ◽  
Ming Li ◽  
Jun An ◽  
Xing Wei Xu ◽  
Shuai Shao
Keyword(s):  
Numerical Simulation ◽  
Simulation Model ◽  
Process Simulation ◽  
Northeast China ◽  
Operation Mode ◽  
Measured Data ◽  
Model Parameters ◽  
Conservative Operation ◽  
Generator Frequency ◽  
Dynamic Frequency

Although numerical simulation is an important method of researching dynamic frequency process, obvious deviations have been found between numerical simulation and the measured trajectory in many accidents. And the existing simulation model and parameters cannot describe the actual dynamic process of frequency accurately. Research was carried out on the influence of four parameters to the dynamic frequency process, which based on the WSCC system. The four parameters include the inertia constant of generator, generator frequency coefficient, dead band and turbine intermediate superheating coefficient. Northeast China power grid and measured data are used to verify the above research conclusion. Checking the dynamic frequency process simulation model and parameters can improve the accuracy of dynamic frequency process simulation on the base of the measured trajectory and the physical characteristics of the parameters. It can also give efficient foundation for the setting work of UFLS, overcoming the previous conservative operation mode and so on.

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