scholarly journals Reliability Estimation for Zero-Failure Data Based on Confidence Limit Analysis Method

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Haiyang Li ◽  
Zeyu Zheng
Keyword(s):  
Confidence Limit ◽  
High Efficiency ◽  
Reliability Estimation ◽  
Estimation Methods ◽  
Single Group ◽  
Failure Data ◽  
Practical Engineering ◽  
Multiple Groups ◽  
Almost All ◽  
Limit Analysis Method

Due to the improvement of the quality of industrial products, zero-failure data often occurs during the reliability life test or in the service environment, and such problems cannot be handled using traditional reliability estimation methods. Regarding the processing and analysis of zero-failure data, the confidence limit assessment methods were proposed by some researchers. Based on the existing research, a confidence limit method set (CLMS) is established in the Weibull distribution for reliability estimation of zero-failure data. The method set includes the unilateral confidence limit method and optimal confidence limit method, so that almost all existing grouping types of zero-failure data can be quickly evaluated, and multiple methods can be used in parallel to deal with the same problem. The effectiveness and high efficiency of the CLMS combined with numerical simulation examples have been verified, and the possibility of analyzing multiple groups of zero-failure data with a confidence limit method suitable for processing single group of zero-failure data is expanded. Finally, the actual effect of the method set is verified by the single group of zero-failure data of rolling bearings and the multiple groups of zero-failure data of torque motors. The results of the example evaluation show that the CLMS has obvious advantages in practical engineering applications.

Reliability Estimates for IRT-Based Forced-Choice Assessment Scores

2021 ◽  
pp. 109442812199908
Author(s):  
Yin Lin
Keyword(s):  
Impression Management ◽  
Empirical Studies ◽  
Forced Choice ◽  
Reliability Estimation ◽  
Estimation Methods ◽  
High Stakes ◽  
Personnel Decisions ◽  
Assessment Scores ◽  
Reliability Estimates ◽  
Different Types

Forced-choice (FC) assessments of noncognitive psychological constructs (e.g., personality, behavioral tendencies) are popular in high-stakes organizational testing scenarios (e.g., informing hiring decisions) due to their enhanced resistance against response distortions (e.g., faking good, impression management). The measurement precisions of FC assessment scores used to inform personnel decisions are of paramount importance in practice. Different types of reliability estimates are reported for FC assessment scores in current publications, while consensus on best practices appears to be lacking. In order to provide understanding and structure around the reporting of FC reliability, this study systematically examined different types of reliability estimation methods for Thurstonian IRT-based FC assessment scores: their theoretical differences were discussed, and their numerical differences were illustrated through a series of simulations and empirical studies. In doing so, this study provides a practical guide for appraising different reliability estimation methods for IRT-based FC assessment scores.

scholarly journals Estimation of Additional Equivalent Damping Ratio of the Damped Structure Based on Energy Dissipation

2019 ◽  
Vol 2019 ◽  
pp. 1-14
Author(s):  
Xiuyan Hu ◽  
Qingjun Chen ◽  
Dagen Weng ◽  
Ruifu Zhang ◽  
Xiaosong Ren
Keyword(s):  
Energy Dissipation ◽  
Damping Ratio ◽  
Theoretical Concept ◽  
Estimation Methods ◽  
External Excitation ◽  
Single Degree Of Freedom ◽  
Equivalent Damping ◽  
Seismic Motion ◽  
Practical Engineering ◽  
Energy Dissipation Capacity

In the design of damped structures, the additional equivalent damping ratio (EDR) is an important factor in the evaluation of the energy dissipation effect. However, previous additional EDR estimation methods are complicated and not easy to be applied in practical engineering. Therefore, in this study, a method based on energy dissipation is developed to simplify the estimation of the additional EDR. First, an energy governing equation is established to calculate the structural energy dissipation. By means of dynamic analysis, the ratio of the energy consumed by dampers to that consumed by structural inherent damping is obtained under external excitation. Because the energy dissipation capacity of the installed dampers is reflected by the additional EDR, the abovementioned ratio can be used to estimate the additional EDR of the damped structure. Energy dissipation varies with time, which indicates that the ratio is related to the duration of ground motion. Hence, the energy dissipation during the most intensive period in the entire seismic motion duration is used to calculate the additional EDR. Accordingly, the procedure of the proposed method is presented. The feasibility of this method is verified by using a single-degree-of-freedom system. Then, a benchmark structure with dampers is adopted to illustrate the usefulness of this method in practical engineering applications. In conclusion, the proposed method is not only explicit in the theoretical concept and convenient in application but also reflects the time-varying characteristic of additional EDR, which possesses the value in practical engineering.

scholarly journals Nuclear-Targeted TAT-PZLL-D3 Co-Delivery DOX and p53 for Chemotherapy Resistance of SCLC

2021 ◽  
Author(s):  
Dan Wang ◽  
Tianshou Cao ◽  
Wanyu Li ◽  
Li Li ◽  
Qunfa Huang ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Drug Resistance ◽  
Tumor Recurrence ◽  
High Efficiency ◽  
Chemotherapy Resistance ◽  
A549 Cells ◽  
Delivery Vector ◽  
Transactivator Of Transcription ◽  
Almost All

Abstract Small cell lung cancer (SCLC) accounts for 13% ~ 15% of lung cancer. It is a subtype with high malignancy and poor prognosis. Almost all patients with SCLC will inevitably have drug resistance and tumor recurrence, which has become an urgent problem in the treatment of SCLC. Nuclear-targeted drug delivery system, which enables intra-nuclear release of anticancer drugs, is expected to address this challenge. In this study, based on transactivator of transcription (TAT)’s active transport property to the nucleus, we developed a high-efficiency nucleus-targeted co-delivery vector that delivers genes and drugs directly into the nucleus of A549 cells. The system is based on a poly-(N-ε-carbobenzyloxy-L-lysine) (PZLL) and dendritic polyamidoamine (PAMAM) block copolymer (PZLL-D3) with TAT modified on the surface of carrier. In vitro studies showed that DOX and p53 could can be effectively transported to the nucleus and kill the cancer cells. Thus, such deliver system would bypass the drug resistance and tumor recurrence problem.

A Fault-Tolerant Offset Algorithm for Measured Data with Defects

2014 ◽  
Vol 902 ◽  
pp. 344-350
Author(s):  
Xiang Jia Li ◽  
Ning Dai ◽  
Wen He Liao ◽  
Yu Chun Sun ◽  
Yong Bo Wang
Keyword(s):  
High Efficiency ◽  
Fault Tolerant ◽  
Engineering Application ◽  
Measured Data ◽  
Sphere Model ◽  
High Quality ◽  
Fitting Method ◽  
Enveloping Surface ◽  
Practical Engineering ◽  
Offset Surface

Offsetting of measured data, as a basic geometric operation, has already been widely used in many areas, like reverse engineering, rapid prototyping and NC machining. However, measured data always carry typical defects like caves and singular points. A fault-tolerant offset method is proposed to create the high quality offset surface of measured data with such defects. Firstly, we generated an expansion sphere model of measured data with the radius equivalent to the offset length. Secondly, using the computational geometry application of convex hull, we acquire the data of outermost enveloping surface of this expansion sphere model. Finally, we use local MLS projection fitting method to wipe out existing defects, and generate the high-quality triangular mesh surface of the offset model. The offset surface generated by this method is suitable for practical engineering application due to its high efficiency and accuracy.

scholarly journals Implementation of Unbalanced Ternary Logic Gates with the Combination of Spintronic Memristor and CMOS

Electronics ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 542 ◽  
Author(s):  
Haifeng Zhang ◽  
Zhaowei Zhang ◽  
Mingyu Gao ◽  
Li Luo ◽  
Shukai Duan ◽  
...  
Keyword(s):  
High Efficiency ◽  
Load Capacity ◽  
Complementary Metal Oxide Semiconductor ◽  
Logic Gates ◽  
Logic Circuit ◽  
Oxide Semiconductor ◽  
Ternary Logic ◽  
Logic Operations ◽  
Almost All ◽  
Logic Functions

A memristor is a nanoscale electronic element that displays a threshold property, non-volatility, and variable conductivity. Its composite circuits are promising for the implementation of intelligence computation, especially for logic operations. In this paper, a flexible logic circuit composed of a spintronic memristor and complementary metal-oxide-semiconductor (CMOS) switches is proposed for the implementation of the basic unbalanced ternary logic gates, including the NAND, NOR, AND, and OR gates. Meanwhile, due to the participation of the memristor and CMOS, the proposed circuit has advantages in terms of non-volatility and load capacity. Furthermore, the input and output of the proposed logic are both constant voltages without signal degradation. All these three merits make the proposed circuit capable of realizing the cascaded logic functions. In order to demonstrate the validity and effectiveness of the entire work, series circuit simulations were carried out. The experimental results indicated that the proposed logic circuit has the potential to realize almost all basic ternary logic gates, and even some more complicated cascaded logic functions with a compact circuit construction, high efficiency, and good robustness.

Practical value of food bait «Fliblok gran-ules» in order to reduce the number of zoo-philic flies at the pig farms

2020 ◽  
Vol 2 ◽  
pp. 51-57
Author(s):  
S.V. Engashev ◽  
◽  
F. I. Vasilevich ◽  
M.D. Novak ◽  
E.S. Engasheva ◽  
...  
Keyword(s):  
High Efficiency ◽  
Food Pellet ◽  
Farm Animals ◽  
Economic Damage ◽  
Blood Sucking ◽  
Russian Federa Tion ◽  
Pig Farms ◽  
Causative Agents ◽  
Pig Farm ◽  
Almost All

Bestial flies are widely spred at various types of livestock enterprises (dairy farms, fattening farms, pig farms, sheep farms, stud farms, poultry farms) of the Russian Federa-tion; they are mechanical and biological carriers of many pathogens of infectious and invasive diseases, can cause anemia and stress in productive farm animals and young animals. The economic damage from infec-tious and parasitic diseases, the causative agents of which carry licking and blood-sucking flies, as well as from a decrease in productivity due to stress, is measured in hundreds of millions of rubles a year. In addition, high costs are required for veteri-nary, anti-epizootic and recreational activi-ties. We conducted a test to study the effective-ness of the Flyblock® food pellet bait (organization-developer of NEC Agrovet-zashchita LLC), an insecticidal and attract-ant measurement during the period of the maximum number of bestial flies on a pig farm.The food bait was tested from the sec-ond half of summer until the end of Septem-ber in three commercial pig farms of the Ryazan Region: 50 x 12 m - experimental, 5 x 12 m - control № 1 (fodder kitchen), 50 x 12 m - control № 2. In the experimental room, the Flyblock® drug granules were distributed by the rate of 5 g per 5 m2 in cardboard containers 12 x 8 cm in size with 4 cm high side walls in plac-es not accessible to animals - window open-ings. The Flyblock® pellet food bait was placed once with regular monitoring (starting from the first day and for 2.5 months) of its effectiveness against bestial flies with the obligatory re-moval of dead flies. Studies have showed the high efficiency of Flyblock® food pellets against bestial flies. The effectiveness of the the drug against licking and bloodsucking flies when keeping pigs for fattening in the premises of a com-mercial pig farm is in almost all cases of research more than 95%.

Research on R245fa Condensation Heat Transfer Characteristic Inside Horizontal Tubes

2016 ◽  
Author(s):  
Shengchun Liu ◽  
Wenkai Zhang ◽  
Ziteng Dong
Keyword(s):  
Heat Transfer ◽  
High Efficiency ◽  
Transfer Characteristic ◽  
Condensation Heat Transfer ◽  
Two Phase ◽  
Horizontal Tubes ◽  
Copper Pipe ◽  
Practical Engineering ◽  
Inner Diameter ◽  
Condensation Heat Transfer Coefficient

Condensation heat transfer of R245fa in horizontal copper pipe is studied in this paper. In the experimental study, the pipe inner diameter is 4.38 mm, the condensing temperature range from 50∼60°C, mass flow rate ranges from 3.132kg/h to 11.988kg/h, and inlet ranges from 0.89∼1. The research results indicate that the condensation coefficient is rose with the condensing; and it will rise when the inlet quality ranges from 0.89 to 1. Experimental value and the existing two-phase flow correlation are compared in this paper. It shows that the condensation heat transfer coefficient predicted by Haraguchi correlation has a high accuracy relatively. The research provides a foundation to promote development of microchannel high efficiency heat exchanger and it is useful to practical engineering.

Evaluation of Air Filtration Options for an Industrial Gas Turbine

2015 ◽  
Author(s):  
Christopher A. Perullo ◽  
Josh Barron ◽  
Dale Grace ◽  
Leonard Angello ◽  
Tim Lieuwen
Keyword(s):  
Pressure Drop ◽  
Gas Turbines ◽  
Life Cycle Cost ◽  
High Efficiency ◽  
Air Filtration ◽  
Unit Output ◽  
Almost All ◽  
The Cost ◽  
The Impact ◽  
Unit Performance

Gas turbines ingest large quantities of air during operation. As a result, large quantities of foreign particles ranging in size from smoke (0.01 to 1.0 micron) to pollen (10 micron) enter the unit and can contribute to both fouling and erosion depending on particle size. Fouling and erosion both lead to reductions in unit output and efficiency resulting in increased operational cost. Operators have historically combatted fouling through a combination of online water washes, more effective off-line water washes, and air filtration. As is the case with almost all engineering problems, the trade-off between the cost and effectiveness of these methods must be evaluated. Online washing is somewhat effective but has led to first stage blade erosion and unit trips in some cases. Off-line washing is more effective at cleaning the unit, but requires the unit to be shut down for extended periods of time. Air filtration can help prevent foreign particles from entering the unit, but higher efficiency filters are generally associated with a larger inlet pressure drop, leading to decreased unit output; this is balanced against reduced fouling rates. These tradeoffs between the costs associated with higher efficiency filters and the frequency of compressor washing need to be evaluated on a plant-by-plant basis to determine the best combination of air filtration and compressor washing programs. This paper presents a field study carried out to determine the effectiveness of high efficiency filters in preventing compressor fouling. Fourteen units at four sites were monitored over a 9 month to 3 year time period to determine the changes in unit performance and the impact of water washes on unit performance for both pre and final filters of lower and higher efficiency ratings. Results to date indicate that higher efficiency filters are effective at reducing the need for off-line water washes and potentially reduce life-cycle cost. Reduced output from the higher pressure drop, high efficiency filters is offset by the better performance retention offered from reduced fouling rates.

Reliability Estimation of Fatigue Life for Machine Parts under Uniaxial Constant Amplitude Load

2012 ◽  
Vol 249-250 ◽  
pp. 632-635
Author(s):  
Yu He Li ◽  
Xin Li Bai ◽  
Ying Fang Zhang
Keyword(s):  
Fatigue Life ◽  
Design Method ◽  
Engineering Application ◽  
Reliability Estimation ◽  
Estimation Methods ◽  
Fatigue Reliability ◽  
Constant Amplitude ◽  
Reliability Design ◽  
Fatigue Design ◽  
Machine Parts

Two methods acquiring p-S-N curve for machine parts are given, namely directly searching out the p-S-N curve of the material from material database and using the idealized p-S-N curve. Reliability estimation methods of fatigue life of machine parts are derived under uniaxial constant amplitude load. Two kinds of circumstances (fixed stress and probabilistic stress) and two kinds of stress cycles (reversed cycle and unsymmetric reversed cycle) are considered. An iteration method is presented and the corresponding computer program is developed for estimating reliable life of machine parts. The engineering application results show that the calculated results are closer to experimental results. The suggested method can be convenient to fatigue reliability design of machine parts. It has good stimulative effect on popularization and application of existing anti-fatigue design method for machine parts, and high value of engineering application.

Sign in / Sign up

Export Citation Format

Share Document