FEATURES OF SELECTING DIELECTRIC LAYERS FOR ELECTROLUMINESCENT STRUCTURES

2021 ◽  
Vol 56 ◽  
pp. 115-122
Author(s):  
V. G. Boiko ◽  

The paper considers an equivalent scheme of a thin-film electroluminescent emitter (TFELE), taking into account dielectric leaks, and proposes a criterion for the optimal choice of a dielectric in the structure to increase its efficiency. A calculation method is proposed for the optimal choice of material for dielectric films in an electroluminescent structure, taking into account their dielectric loss tangent. The algorithm for optimizing the parameters is based on the method of pairwise comparison of two dielectrics, provided that the charge flowing through the structure is constant or increased. The calculated data for materials are given in the form of a table according to the sequence of deterioration of their characteristics. The most attractive of the materials considered are PbTiO3, Ta2O5, Y2O3, as well as improved ceramics, which is confirmed by experiment. The possibility of applying the proposed model to explain the dependence of the luminosity of electroluminescent emitters on their excitation voltage is shown. A comparative analysis of the results of the calculation and experiment of the dependence of brightness on the applied voltage (B-V) for three types of TFELE based on a luminescent layer ZnS : Mn (0.5%) with a thickness of 0.6 μm, placed between two dielectric layers with a thickness of about 0.3- 0.35 μm with Ta2O5, Sm2O3 and Y2O3, respectively. It is established that the threshold luminescence excitation voltage correlates with the value of εE, and the maximum brightness with the value of εE / tg (δ). The table also shows the calculated characteristics of NdAlO3 and AlN films deposited by high-frequency magnetron sputtering. Higher brightness values can be expected from electroluminescent structures with such a dielectric than from structures with dielectric films with Sm2O3 and Y2O3. The results of such studies are presented in the form of a graph and table. This method can find practical application in the development of new materials and technologies for their production.

Author(s):  
D. Zudhistira ◽  
V. Viswanathan ◽  
V. Narang ◽  
J.M. Chin ◽  
S. Sharang ◽  
...  

Abstract Deprocessing is an essential step in the physical failure analysis of ICs. Typically, this is accomplished by techniques such as wet chemical methods, RIE, and mechanical manual polishing. Manual polishing suffers from highly non-uniform delayering particularly for sub 20nm technologies due to aggressive back-end-of-line scaling and porous ultra low-k dielectric films. Recently gas assisted Xe plasma FIB has demonstrated uniform delayering of the metal and dielectric layers, achieving a planar surface of heterogeneous materials. In this paper, the successful application of this technique to delayer sub-20 nm microprocessor chips with real defects to root cause the failure is presented.


Author(s):  
A. V. Ponomarev

Introduction: Large-scale human-computer systems involving people of various skills and motivation into the information processing process are currently used in a wide spectrum of applications. An acute problem in such systems is assessing the expected quality of each contributor; for example, in order to penalize incompetent or inaccurate ones and to promote diligent ones.Purpose: To develop a method of assessing the expected contributor’s quality in community tagging systems. This method should only use generally unreliable and incomplete information provided by contributors (with ground truth tags unknown).Results:A mathematical model is proposed for community image tagging (including the model of a contributor), along with a method of assessing the expected contributor’s quality. The method is based on comparing tag sets provided by different contributors for the same images, being a modification of pairwise comparison method with preference relation replaced by a special domination characteristic. Expected contributors’ quality is evaluated as a positive eigenvector of a pairwise domination characteristic matrix. Community tagging simulation has confirmed that the proposed method allows you to adequately estimate the expected quality of community tagging system contributors (provided that the contributors' behavior fits the proposed model).Practical relevance: The obtained results can be used in the development of systems based on coordinated efforts of community (primarily, community tagging systems). 


2014 ◽  
Vol 14 (7) ◽  
pp. 1663-1676 ◽  
Author(s):  
M. Brazdova ◽  
J. Riha

Abstract. In this paper a model for the estimation of the number of potential fatalities is proposed based on data from 19 past floods in central Europe. First, the factors contributing to human losses during river floods are listed and assigned to the main risk factors: hazard – exposure – vulnerability. The order of significance of individual factors has been compiled by pairwise comparison based on experience with real flood events. A comparison with factors used in existing models for the estimation of fatalities during floods shows good agreement with the significant factors identified in this study. The most significant factors affecting the number of human losses in floods have been aggregated into three groups and subjected to correlation analysis. A close-fitting regression dependence is proposed for the estimation of loss of life and calibrated using data from selected real floods in central Europe. The application of the proposed model for the estimation of fatalities due to river floods is shown via a flood risk assessment for the locality of Krnov in the Czech Republic.


2011 ◽  
Vol 18 (3) ◽  
pp. 66-70 ◽  
Author(s):  
H. Mehdigholi ◽  
H. Rafsanjani ◽  
Behzad Mehdi

Estimation of rolling bearing life with damage curve approach The ability to determine the bearing life time is one of the main purposes in maintenance of rotating machineries. Because of reliability, cost and productivity, the bearing life time prognostic is important. In this paper, a stiffness-based prognostic model for bearing systems is discussed. According to presumed model of bearing and fundamental of damage mechanics, damage curve approach is used to relate stiffness of vibratory system and bearing running life. Furthermore, using the relation between acceleration amplitude at natural frequency and stiffness, final relation between acceleration amplitude at natural frequency and running life time according to damage curve approach can be established and the final running time is predicted. Experiments have been performed on self alignment bearing under failures on inner race and outer race to calibrate and to validate the proposed model. The comparison between model-calculated data and experimental results indicates that this model can be used effectively to predict the failure lifetime and the remaining life of a bearing system.


Author(s):  
Shan Jin ◽  
Shuai Yuan ◽  
Ting Liu ◽  
Peihua Han ◽  
Yong Bai

Steel strip reinforced flexible pipe (SSRFP) is a kind of unbonded composite pipe, which has more application foreground in offshore engineering due to its excellent mechanics and the considerable flexibility. In practical application, SSRFP will inevitably experience bending during reeling process and installation. In this paper, the mechanical behavior of SSRFP subjected to pure bending are studied both experimentally and numerically. A four-point bending equipment is utilized to conduct the full-scale laboratorial tests of SSRFP. Furthermore, the commercial software ABAQUS is employed to simulate its ovalization instability. The results acquired from the ABAQUS simulation are compared with the ones from verification bending experiment, which are in good coincidence with each other. The proposed model and the relative results may be of interest to the manufacture factory engineers.


Author(s):  
Kotchapong Sumanonta ◽  
Pasist Suwanapingkarl ◽  
Pisit Liutanakul

This article presents a novel model for the equivalent circuit of a photovoltaic module. This circuit consists of the following important parameters: a single diode, series resistance (Rs) and parallel resistance (Rp) that can be directly adjusted according to ambient temperature and the irradiance. The single diode in the circuit is directly related to the ideality factor (m), which represents the relationship between the materials and significant structures of PV module such as mono crystalline, multi crystalline and thin film technology.  Especially, the proposed model in this article is to present the simplified model that can calculate the results of I-V curves faster and more accurate than other methods of the previous models. This can show that the proposed models are more suitable for the practical application. In addition, the results of the proposed model are validated by the datasheet, the practical data in the laboratory (indoor test) and the onsite data (outdoor test). This ensures that the less than 0.1% absolute errors of the model can be accepted.


2018 ◽  
Vol 5 (2) ◽  
Author(s):  
Hanky Fransiscus ◽  
Cyntiarani Karyoko Karyoko ◽  
Bagus Made Arthaya

Industri kreatif memiliki kontribusi yang besar bagi perekonomian Indonesia, membuka lapangan kerja baru, serta memperkuat citra dan identitas bangsa. Salah satu bagian dari industri kreatif adalah pengrajin kulit. Produk yang dihasilkan oleh pengrajin cukup bervariasi, seperti dompet, sepatu, tas, dll. Material kulit yang digunakan berupa kulit asli atau kulit sintetis. Salah satu proses dalam menghasilkan produk-produk tersebut adalah embossing untuk membentuk pola hias atau merk. Embossing dapat dilakukan dengan dengan high frequency welding. High frequency welding merupakan penyatuan material dengan menggunakan energi elektromagnetik frekuensi tinggi untuk menghasilkan panas pada material polar sehingga meleleh dan menghasilkan bentuk seperti yang diinginkan setelah proses pendinginan. Laboratorium Proses Produksi Program Studi Teknik Industri memiliki mesin high frequency welding yang dapat digunakan sebagai materi praktikum serta membantu pengrajin kulit kota Bandung, khususnya pengrajin kulit Cibaduyut untuk menghasilkan emboss yang baik. Embossing kulit sintetis dan kulit asli memerlukan parameter proses yang berbeda, hal ini disebabkan sifat fisik setiap jenis kulit. Oleh karena itu diteliti parameter yang tepat untuk menghasilkan emboss kulit sintetis. Penelitian ini menggunakan kulit sintetis yang terbuat dari PVC (Polivinil Klorida). Cetakan yang digunakan merupakan cetakan sederhana berbentuk 2 lingkaran, yaitu lingkaran dalam dan lingkaran luar. Parameter yang diteliti terdiri dari 2 parameter, yaitu suhu dan waktu pengelasan. Eksperimen dilakukan dengan 3 level suhu, yaitu 140°C, 160°C, dan 170°C sedangkan waktu pengelasan dilakukan dengan 3 level yaitu 3 detik, 7 detik, dan 10 detik. Response dari eksperimen ini adalah jari-jari dalam dan jari-jari luar emboss. Hasil proses embossing dipindai dengan menggunakan 3D Scanner dan kemudian dilakukan pengukuran dengan menggunakan perangkat lunak reverse engineering. Pengaruh dari kedua faktor dan interaksinya diketahui dengan menggunakan ANOVA. Pairwise comparison dilakukan dengan menggunakan Tukey’s method. Hasil yang diperoleh adalah suhu mempengaruhi response. Berdasarkan percobaan yang dilakukan hasil embossing dengan suhu sebesar 170oC lebih baik daripada 140oC atau 160oC. Kata kunci: high frequency welding, design of experiment, kulit sintetis, pvc


2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Zaher Sepehrian ◽  
Sahar Khoshfetrat ◽  
Said Ebadi

Data envelopment analysis (DEA) has been used for obtaining weights for the analytic hierarchy process (AHP), an approach known as DEAHP. This method sometimes identifies more than one decision criterion or alternative as DEAHP-efficient. To overcome this problem, this paper proposes a new approach that not only generates appropriate weights for the decision criteria or alternatives, but also differentiates between DEAHP-efficient decision criteria or alternatives. To this end, we propose a DEA model with an assurance region and a cross-weight model that prioritizes decision criteria or alternatives by considering their most unfavorable weights. Two numerical examples are also provided to illustrate the advantages and potential applications of the proposed model.


Symmetry ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 243 ◽  
Author(s):  
Sarbast Moslem ◽  
Danish Farooq ◽  
Omid Ghorbanzadeh ◽  
Thomas Blaschke

The use of driver behavior has been considered a complex way to solve road safety complications. Car drivers are usually involved in various risky driving factors which lead to accidents where people are fatally or seriously injured. The present study aims to dissect and rank the significant driver behavior factors related to road safety by applying an integrated multi-criteria decision-making (MCDM) model, which is structured as a hierarchy with at least one 5 × 5 (or bigger) pairwise comparison matrix (PCM). A real-world, complex decision-making problem was selected to evaluate the possible application of the proposed model (driver behavior preferences related to road safety problems). The application of the analytic hierarchy process (AHP) alone, by precluding layman participants, might cause a loss of reliable information in the case of the decision-making systems with big PCMs. Evading this tricky issue, we used the Best Worst Method (BWM) to make the layman’s evaluator task easier and timesaving. Therefore, the AHP-BWM model was found to be a suitable integration to evaluate risky driver behavior factors within a designed three-level hierarchical structure. The model results found the most significant driver behavior factors that influence road safety for each level, based on evaluator responses on the driver behavior questionnaire (DBQ). Moreover, the output vector of weights in the integrated model is more consistent, with results for 5 × 5 PCMs or bigger. The proposed AHP-BWM model can be used for PCMs with scientific data organized by traditional means.


Kybernetes ◽  
2010 ◽  
Vol 39 (1) ◽  
pp. 37-54 ◽  
Author(s):  
He‐Yau Kang ◽  
Amy H.I. Lee

PurposeMost industries have become increasingly competitive nowadays, and a good supply chain relationship is essential for a company to survive and to acquire reasonable profit. Therefore, supplier selection is very important. The purpose of this paper is to propose a novel model for evaluating the performance of suppliers.Design/methodology/approachA supplier performance evaluation model based on analytic hierarchy process (AHP) and data envelopment analysis (DEA) is constructed. DEA is applied first to evaluate quantitative factors, and the results are transformed into pairwise comparison values for AHP analysis. Qualitative factors are also evaluated through AHP analysis, and a final ranking of suppliers can be obtained by combining the quantitative and qualitative results.FindingsThe proposed model can be applied to evaluate and select the most appropriate integrated circuit packaging company for outsourcing. With the incorporation of experts' opinions and the consideration of qualitative and quantitative factors, the model can provide a both subjective and objective supplier performance ranking.Practical implicationsThe proposed model can be tailored and applied to supplier evaluation and selection in other industries.Originality/valueAlthough many models are available for supplier evaluation, this paper considers both the subjective and objective performance characteristics simultaneously in the evaluation process.


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