scholarly journals Comparison of reliability evaluation methods between China and Canada standards for wood structures featuring duration of load

2020 ◽  
Vol 66 (1) ◽  
Author(s):  
Qiongyao Wu ◽  
Shuang Niu ◽  
Enchun Zhu
Keyword(s):  
Reliability Analysis ◽  
Analysis Method ◽  
Safety Level ◽  
Wood Structures ◽  
Load Effect ◽  
Key Factor ◽  
Live Loads ◽  
High Level ◽  
Partial Factor ◽  
Duration Of Load

Abstract Duration of load (DOL) is a key factor in design of wood structures, which makes the reliability analysis of wood structures more complicated. The importance of DOL is widely recognized, yet the methods and models through which it is incorporated into design codes vary substantially by country/region. Few investigations of the effect of different model assumptions of DOL and other random variables on the results of reliability analysis of wood structures can be found. In this paper, comparisons are made on the reliability analysis methods that underlie the China and the Canada standards for design of wood structures. Main characteristics of these two methods, especially the way how DOL is treated are investigated. Reliability analysis was carried out with the two methods employing the same set of material properties and load parameters. The resulted relationships between reliability index β and resistance partial factor γR* (the β–γR* curves) for four load combinations are compared to study the safety level indicated by the two methods. The comparison shows that the damage accumulation model (Foschi–Yao model) in the Canada analysis method is highly dependent on the type and duration of load, resulting in more conservative design than the China analysis method in loading cases dominated by dead load, but less conservative design in cases of high level of live loads. The characteristics of the load effect term of the performance function are also found to make considerable difference in reliability levels between the two methods. This study aims to provide references for researchers and standard developers in the field of wood structures.

Determination of the Optimum Partial Factors in Structural Reliability Analysis

1998 ◽  
Vol 05 (02) ◽  
pp. 169-180 ◽  
Author(s):  
D. H. Li ◽  
C. Y. Tang ◽  
M. Jie ◽  
Albert H. C. Tsang ◽  
Y. C. Tsim
Keyword(s):  
Objective Function ◽  
Reliability Analysis ◽  
Structural Reliability ◽  
Optimization Method ◽  
Design Criterion ◽  
Resistance Force ◽  
Reliability Design ◽  
Structural Reliability Analysis ◽  
Live Loads ◽  
Partial Factor

In this paper, an optimization method is used to determine the values of partial factors in structural reliability analysis. Once the proper objective function is defined, a group of optimum partial factors, which enable the objective function to take its minimum value, will need to be determined. In the present study, two kinds of objective function are considered. The conditions that have to be satisfied for optimum partial factors of these two kinds of objective function are then derived. In both cases, the result shows that the partial factors of both dead and live loads should satisfy the same proportional expression and should be inversely proportional to the partial factor of resistance force. A simple beam is used as an example to illustrate the computations involved. It is found that the design concept proposed in this paper leads to a design criterion similar to that which applies to the conventional deterministic method. Thus, this concept can be easily used in practice. The illustrative example shows that the values of the dead load and live load have a significant effect on the reliability design criteria.

Analisis SWOT (Strength, Weakness, Opportunities, Threats) Melalui Inkuiri Terbimbing Pada Materi Kegiatan Ekonomi Mahasiswa Pendidikan Guru Sekolah Dasar

2019 ◽  
Vol 1 (2) ◽  
pp. 141
Author(s):  
Iis Yeni Sugiarti
Keyword(s):  
Swot Analysis ◽  
Descriptive Analysis ◽  
Qualitative Approach ◽  
Guided Inquiry ◽  
Analysis Method ◽  
Economic Activities ◽  
External Analysis ◽  
High Level ◽  
Center Area ◽  
Trade Competition

Abstrak. Desa Trusmi merupakan sentra batik sekaligus kuliner di Kabupaten Cirebon. Banyaknya pemegang usaha di bidang produksi batik mengakibatkan persaingan dagang diwilayah tersebut. Penelitian ini bertujuan untuk menganalisis SWOT (Strength, Weakness, Opportunities, Threats)  di salah satu usaha batik milik H. Edi Baredi atau sering dikenal dengan EB Batik Tradisional melalui inkuri terbimbing. Analisis meliputi profil usaha, aspek produksi, aspek tenaga kerja, aspek pemasaran dan aspek keuangan. Jenis penelitian ini menggunakan pendekatan kualitatif dengan metode deskripstif analisis. Berdasarkan analisis internal dan eksternal analisis SWOT, strategi yang  dilakukan oleh EB Batik Tradisional yaitu menghindari kehilangan penjualan dan profit yang disebabkan banyaknya persaingan dagang di kawasan sentra batik Trusmi dengan munculnya inovasi baru. Penguatan karakter pada produksi batiknya dapat mengatasi pesaingan dagang dan menambah daya tarik pembeli. Kata Kunci: SWOT, Inkuiri Terbimbing, dan Kegiatan Ekonomi Abstract. Trusmi village is a center of batik as well as culinary in Cirebon Regency. A large number of business holders in the field of batik production has resulted in trade competition in the region. This study aims to analyze SWOT (Strength, Weakness, Opportunities, Threats) in one of the batik business owned by H. Edi Baredi or often known as EB Traditional Batik through guided injury. The analysis includes the business profile, production aspects, labor aspects, marketing aspects, and financial aspects. This type of research uses a qualitative approach with descriptive analysis method. Based on internal and external analysis of the SWOT analysis, the strategy carried out by EB Traditional Batik is to avoid losing sales and profits due to the high level of trade competition in the Trusmi batik center area with the emergence of innovations. Strengthening the character of batik production can overcome trade competition and increase the attractiveness of buyers. Keywords: SWOT, Guided Inquiry, and Economic Activities

scholarly journals Analysis of Lipid Peroxidation by UPLC-MS/MS and Retinoprotective Effects of the Natural Polyphenol Pterostilbene

Antioxidants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 168
Author(s):  
Isabel Torres-Cuevas ◽  
Iván Millán ◽  
Miguel Asensi ◽  
Máximo Vento ◽  
Camille Oger ◽  
...  
Keyword(s):  
Lipid Peroxidation ◽  
Diabetic Retinopathy ◽  
Redox Homeostasis ◽  
Ultra Performance Liquid Chromatography ◽  
Protective Effects ◽  
Diabetic Retina ◽  
Key Factor ◽  
Adrenic Acid ◽  
Diabetic Rabbits ◽  
High Level

The loss of redox homeostasis induced by hyperglycemia is an early sign and key factor in the development of diabetic retinopathy. Due to the high level of long-chain polyunsaturated fatty acids, diabetic retina is highly susceptible to lipid peroxidation, source of pathophysiological alterations in diabetic retinopathy. Previous studies have shown that pterostilbene, a natural antioxidant polyphenol, is an effective therapy against diabetic retinopathy development, although its protective effects on lipid peroxidation are not well known. Plasma, urine and retinas from diabetic rabbits, control and diabetic rabbits treated daily with pterostilbene were analyzed. Lipid peroxidation was evaluated through the determination of derivatives from arachidonic, adrenic and docosahexaenoic acids by ultra-performance liquid chromatography coupled with tandem mass spectrometry. Diabetes increased lipid peroxidation in retina, plasma and urine samples and pterostilbene treatment restored control values, showing its ability to prevent early and main alterations in the development of diabetic retinopathy. Through our study, we are able to propose the use of a derivative of adrenic acid, 17(RS)-10-epi-SC-Δ15-11-dihomo-IsoF, for the first time, as a suitable biomarker of diabetic retinopathy in plasmas or urine.

scholarly journals An Efficient Time-Variant Reliability Analysis Method with Mixed Uncertainties

Algorithms ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 229
Author(s):  
Fangyi Li ◽  
Yufei Yan ◽  
Jianhua Rong ◽  
Houyao Zhu
Keyword(s):  
Reliability Analysis ◽  
Limit State ◽  
Random Variables ◽  
Equivalent Model ◽  
Independent Random Variables ◽  
Problem Analysis ◽  
Analysis Method ◽  
Calculation Algorithm ◽  
Reliability Problem ◽  
Interval Variables

In practical engineering, due to the lack of information, it is impossible to accurately determine the distribution of all variables. Therefore, time-variant reliability problems with both random and interval variables may be encountered. However, this kind of problem usually involves a complex multilevel nested optimization problem, which leads to a substantial computational burden, and it is difficult to meet the requirements of complex engineering problem analysis. This study proposes a decoupling strategy to efficiently analyze the time-variant reliability based on the mixed uncertainty model. The interval variables are treated with independent random variables that are uniformly distributed in their respective intervals. Then the time-variant reliability-equivalent model, containing only random variables, is established, to avoid multi-layer nesting optimization. The stochastic process is first discretized to obtain several static limit state functions at different times. The time-variant reliability problem is changed into the conventional time-invariant system reliability problem. First order reliability analysis method (FORM) is used to analyze the reliability of each time. Thus, an efficient and robust convergence hybrid time-variant reliability calculation algorithm is proposed based on the equivalent model. Finally, numerical examples shows the effectiveness of the proposed method.

scholarly journals Use of Pediatric Injectable Medicines Guidelines and Associated Medication Administration Errors: A Human Reliability Analysis

2021 ◽  
pp. 106002802199964
Author(s):  
Matthew D. Jones ◽  
Jonathan Clarke ◽  
Calandra Feather ◽  
Bryony Dean Franklin ◽  
Ruchi Sinha ◽  
...  
Keyword(s):  
Reliability Analysis ◽  
Medication Administration ◽  
Original Study ◽  
Human Reliability ◽  
Large Magnitude ◽  
Human Reliability Analysis ◽  
Video Recordings ◽  
Medication Administration Errors ◽  
Key Factor ◽  
Clinically Significant

Background: In a recent human reliability analysis (HRA) of simulated pediatric resuscitations, ineffective retrieval of preparation and administration instructions from online injectable medicines guidelines was a key factor contributing to medication administration errors (MAEs). Objective: The aim of the present study was to use a specific HRA to understand where intravenous medicines guidelines are vulnerable to misinterpretation, focusing on deviations from expected practice ( discrepancies) that contributed to large-magnitude and/or clinically significant MAEs. Methods: Video recordings from the original study were reanalyzed to identify discrepancies in the steps required to find and extract information from the NHS Injectable Medicines Guide (IMG) website. These data were combined with MAE data from the same original study. Results: In total, 44 discrepancies during use of the IMG were observed across 180 medication administrations. Of these discrepancies, 21 (48%) were associated with an MAE, 16 of which (36% of 44 discrepancies) made a major contribution to that error. There were more discrepancies (31 in total, 70%) during the steps required to access the correct drug webpage than there were in the steps required to read this information (13 in total, 30%). Discrepancies when using injectable medicines guidelines made a major contribution to 6 (27%) of 22 clinically significant and 4 (15%) of 27 large-magnitude MAEs. Conclusion and Relevance: Discrepancies during the use of an online injectable medicines guideline were often associated with subsequent MAEs, including those with potentially significant consequences. This highlights the need to test the usability of guidelines before clinical use.

Reliability Analysis Method on Repairable System with Standby Structure Based on Goal Oriented Methodology

2015 ◽  
Vol 32 (7) ◽  
pp. 2505-2517 ◽  
Author(s):  
Xiao-jian Yi ◽  
B.S. Dhillon ◽  
Jian Shi ◽  
Hui-na Mu ◽  
Hai-ping Dong
Keyword(s):  
Reliability Analysis ◽  
Repairable System ◽  
Analysis Method

A Probabilistic and Interval Hybrid Reliability Analysis Method for Structures with Correlated Uncertain Parameters

2015 ◽  
Vol 12 (04) ◽  
pp. 1540006 ◽  
Author(s):  
C. Jiang ◽  
J. Zheng ◽  
B. Y. Ni ◽  
X. Han
Keyword(s):  
Reliability Analysis ◽  
Structural Reliability ◽  
Correlation Coefficients ◽  
Analysis Method ◽  
Analysis Model ◽  
Probability Interval ◽  
Uncertain Variables ◽  
Uncertainty Model ◽  
Sample Correlation ◽  
Hybrid Reliability

This paper proposes a probability-interval mixed uncertainty model considering parametric correlations and a corresponding structural reliability analysis method. First of all, we introduce the sample correlation coefficients to express the correlations between different kinds of uncertain variables including probability and interval variables. Then dependent parameters are transformed into independent ones through a matrix transformation. A reliability analysis model is put forward, and an efficient method is built to obtain the reliability index or failure probability interval of the structure. Finally, four numerical examples are provided to verify the validity of the method.

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