scholarly journals Procedure for the Selection of Rubber Compound in Rubber-Metal Springs for Vibration Isolation

Polymers ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 1737
Author(s):  
Milan Banić ◽  
Dušan Stamenković ◽  
Aleksandar Miltenović ◽  
Dragan Jovanović ◽  
Milan Tica
Keyword(s):  
Numerical Simulation ◽  
Constitutive Model ◽  
Vibration Isolation ◽  
Correct Selection ◽  
Virtual Experiment ◽  
Rubber Compound ◽  
Key Factor ◽  
Railway Engineering ◽  
Selection Of

The selection of a rubber compound has a determining influence on the final characteristics of rubber-metal springs. Therefore, the correct selection of a rubber compound is a key factor for development of rubber-metal vibration isolation springs with required characteristics. The procedure for the selection of the rubber compound for vibration isolation of rubber-metal springs has been proposed, so that the rubber-metal elements have the necessary characteristics, especially in terms of deflection. The procedure is based on numerical simulation of spring deflection with Bergström-Boyce constitutive model in virtual experiment, with a goal to determine which parameters of the constitutive model will lead to spring required deflection. The procedure was verified by case study defined to select rubber compound for a rubber–metal spring used in railway engineering.

scholarly journals Why We Go Where We Go: Profiling User Decisions on Choosing POIs

2020 ◽  
Author(s):  
Renjun Hu ◽  
Xinjiang Lu ◽  
Chuanren Liu ◽  
Yanyan Li ◽  
Hao Liu ◽  
...  
Keyword(s):  
Key Factors ◽  
Real World Data ◽  
Decision Factors ◽  
Point Of Interest ◽  
Learning Factor ◽  
Poi Recommendation ◽  
Key Factor ◽  
Selection Of ◽  
Decision Structures

While Point-of-Interest (POI) recommendation has been a popular topic of study for some time, little progress has been made for understanding why and how people make their decisions for the selection of POIs. To this end, in this paper, we propose a user decision profiling framework, named PROUD, which can identify the key factors in people's decisions on choosing POIs. Specifically, we treat each user decision as a set of factors and provide a method for learning factor embeddings. A unique perspective of our approach is to identify key factors, while preserving decision structures seamlessly, via a novel scalar projection maximization objective. Exactly solving the objective is non-trivial due to a sparsity constraint. To address this, our PROUD adopts a self projection attention and an L2 regularized sparse activation to directly estimate the likelihood of each factor to be a key factor. Finally, extensive experiments on real-world data validate the advantage of PROUD in preserving user decision structures. Also, our case study indicates that the identified key decision factors can help us to provide more interpretable recommendations and analyses.

scholarly journals INFLUENCE OF RIBBING ON THE STRESS-STRAIN STATE OF A FLAT ROUND TANK BOTTOM

2021 ◽  
Vol 112 ◽  
pp. 77-80
Author(s):  
А.K. Baibulov ◽  
◽  
N.V. Ivanitskaya ◽  
Keyword(s):  
Numerical Simulation ◽  
Strain State ◽  
Low Pressure ◽  
Correct Selection ◽  
Stress Strain ◽  
Stress Strain State ◽  
Head Surface ◽  
Tank Bottom ◽  
Rib Arrangement ◽  
Selection Of

Options with radial and longitudinal-transverse rib arrangement were considered. The research was carried out by numerical simulation in the ANSYS program. The values of stresses and deformations in the tank bottom were obtained depending on the number and location of stiffeners on it. It is established that the main load is perceived by the Central part of the ribs. Therefore, due to the correct selection of stiffeners, it is possible to reduce the thickness of the head plate. To equalize the stresses on the head surface, the number of edges should be at least six, and the radial placement of the edges is more preferable. With the same deformations, in this case, the stresses in the head are somewhat less. The results obtained make it possible to increase the strength of the flat head and use it in tanks intended for storing liquid and gaseous substances under low pressure.

Studies regarding correct selection of statistical methods for the needs of increasing the efficiency of identification of land for consolidation—A case study in Poland

2019 ◽  
Vol 87 ◽  
pp. 104064 ◽  
Author(s):  
Justyna Wójcik-Leń ◽  
Przemysław Leń ◽  
Monika Mika ◽  
Hubert Kryszk ◽  
Paweł Kotlarz
Keyword(s):  
Statistical Methods ◽  
Correct Selection ◽  
Selection Of

scholarly journals Peak Power of Heat Source for Domestic Hot Water Preparation (DHW) for Residential Estate in Poland as a Representative Case Study for the Climate of Central Europe

Energies ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 8047
Author(s):  
Łukasz Amanowicz
Keyword(s):  
Heat Source ◽  
Peak Power ◽  
Residential Buildings ◽  
Renewable Energy Sources ◽  
Hot Water ◽  
Correct Selection ◽  
Domestic Hot Water ◽  
Heat Demand ◽  
Selection Of

Due to the energy transformation in buildings, the proportions of energy consumption for heating, ventilation and domestic hot water preparation (DHW) have changed. The latter component can now play a significant role, not only in the context of the annual heat demand, but also in the context of selecting the peak power of the heat source. In this paper, the comparison of chosen methods for its calculation is presented. The results show that for contemporary residential buildings, the peak power for DHW preparation can achieve the same or higher value as the peak power for heating and ventilation. For this reason, nowadays the correct selection of the peak power of a heat source for DHW purposes becomes more important, especially if it uses renewable energy sources, because it affects its size and so the investment cost and economic efficiency. It is also indicated that in modern buildings, mainly accumulative systems with hot water storage tanks should be taken into account because they are less sensitive to design errors (wrongly selected peak value in the context of the uncertainty of hot water consumption) and because they result in acceptable value of peak power for DHW in comparison to heating and ventilation.

Instrumentation Selection and Uncertainty Analysis for Performance Test of Small Centrifugal Compressors

2004 ◽  
Author(s):  
Amro M. Al-Qutub ◽  
Fahad A. Al-Sulaiman
Keyword(s):  
Uncertainty Analysis ◽  
Performance Test ◽  
Correct Selection ◽  
Small Scale ◽  
Performance Parameters ◽  
Centrifugal Compressors ◽  
Accuracy Of Results ◽  
Lower Uncertainty ◽  
Selection Of

In the design phase of centrifugal compressors, it is essential to have some experimental results on performance. The extent of usefulness of the experiments depends on quality and accuracy of the results. Part of proper experimental procedure is the correct selection of instrumentation leading to lower uncertainty in the final results. ASME PTC 10 (Performance Test Code on Compressors and Exhausters) requires fluctuation limits on the measured performance parameters. This does not guarantee limits for accuracy of performance parameters. Also, different experimental setup will affect uncertainty of the results, even with similar instrumentation accuracy. The present research deals with uncertainty analysis for performance evaluation of small-scale centrifugal compressor. The instrumentation errors are accommodated in the relation to ASME PTC 19.1 (test uncertainty). The analysis takes into consideration the correlated bias limits. Selection of proper type of instruments for measuring associated parameters is based on literature review. A case study is included as an example to illustrate the selection on instrumentation accuracy and preferred bias correlations. The analysis is a useful tool in designing experiments for testing compressor and optimizing accuracy of results.

Numerical Simulation of a BPH Thermal Therapy—A Case Study Involving TUMT

2006 ◽  
Vol 129 (4) ◽  
pp. 548-557 ◽  
Author(s):  
John P. Abraham ◽  
Ephraim M. Sparrow ◽  
Satish Ramadhyani
Keyword(s):  
Numerical Simulation ◽  
Phase Change ◽  
Medical Records ◽  
Interstitial Water ◽  
Fatty Tissue ◽  
Deep Tissue ◽  
Temperature Liquid ◽  
Medical Examinations ◽  
Selection Of

The use of numerical simulation as a means to predict the outcome of transurethral microwave thermotherapy (TUMT) is set forth in detail. The simulation was carried out as a case study of a specific TUMT procedure. The selection of the case study was based on the availability of extensive medical records which documented an extraordinary application of TUMT. Predictions were made of the time-varying temperature patterns within the prostate, the bladder, the sphincter, the pelvic floor, and the fat and connective tissue which envelop these organs. These temperature patterns provided the basis of maps which highlighted those locations where necrosis occurred. An injury integral was used to predict the extent of the necrotic tissue produced by the therapy. It was found that, for the specific case being considered, necrosis occurred not only within the prostate but also extended to the neck of the bladder and to the fatty tissue. A special feature of the simulation was the accounting of the liquid-to-vapor phase change of the interstitial water. The vapor generated by the phase change is believed to significantly enlarge the region of necrosis. By the same token, the vapor pressure is expected to cause motion of the high-temperature liquid to deep-tissue regions. The damage predicted by the numerical simulation was compared, in detail, with post-operative medical examinations and found to be corroborated.

scholarly journals Load Capacity and Displacement of Recycled Concrete and Self-Insulation Block Masonry Wall

Materials ◽  
2020 ◽  
Vol 13 (4) ◽  
pp. 863 ◽  
Author(s):  
Huizhi Zhang ◽  
Jifeng Liu ◽  
Yang Yue ◽  
Xiuqin Cui ◽  
Yuezong Lian
Keyword(s):  
Numerical Simulation ◽  
Compressive Strength ◽  
Constitutive Model ◽  
Simulation Analysis ◽  
Load Capacity ◽  
Engineering Application ◽  
Experimental Tests ◽  
Recycled Concrete ◽  
Strength Increase ◽  
Selection Of

In order to discuss the load capacity and displacement of masonry constructed with recycled concrete and self-insulation blocks, one type of 10.6 MPa compressive strength block and three kinds of mortar with M15, M10, and M5 compressive strengths are selected. The constitutive model and corresponding parameters selection of different materials in the ABAQUS numerical simulation are analyzed, and the numerical simulation analysis and experimental tests of the load capacity and displacement of masonry constructed with mortars of different strengths are carried out. The results show that masonry compression failure is controlled by the mortar or block that has the lower compressive strength. The displacement of masonry increases with the mortar compressive strength increase, and the higher mortar compressive strength is beneficial for improving the load capacity and displacement of masonry. Reasonable selection of the constitutive model and parameters will help to obtain reasonable results for the ABAQUS numerical simulation. Construction quality and loading method will affect the load capacity and displacement of the masonry. The above conclusion can provide reference for the engineering application of recycled concrete and self-insulation blocks.

scholarly journals Evaluation of roadside service centers. Case study: Zahedan to Khash Road

2017 ◽  
Vol 7 (4) ◽  
pp. 374-381
Author(s):  
Maryam Karimiyan Bostani ◽  
Fateme Hashemzehi ◽  
Mahmood Reza Anvari
Keyword(s):  
Correct Selection ◽  
Transportation Industry ◽  
Related Factors ◽  
Job Opportunities ◽  
Selection Systems ◽  
Research Findings ◽  
The City ◽  
Selection Of

In the recent century, the excessive and unplanned growth of urbanism and inattention to the proper and correct selection of locations for roadside uses, especially roadside services, have led to the appearance of problems such as lack of spaces for service centers, inappropriate access, and other problems. The strategic location of the city of Zahedan among other cities of Sistan and Baluchistan Province and its connection to the national corridors requires development and growth of transportation industry and improvement of its performance. Some of the utmost important centers that have to be established for this purpose on the roadsides in the required quantities are roadside service and welfare centers. Therefore, in order to maintain and promote the security of the roads in the country, the establishment of such centers requires studies, evaluations and eventually, determination of appropriate and secure locations. In this study, considering the necessity of establishing service and welfare centers on the Zahedan to Khash Road, first, the existing centers were evaluated from the perspectives of passengers, then, by the use of site selection systems, some locations were determined in the high traffic parts of this road. The research methodology in this study is descriptive-analytical which is used in order to analyze the collected data. The research findings show that according to the passengers, the conditions of roadside services on the Zahedan to Khash Road and the existing infrastructures are weak. However, they are satisfied with social and security-related factors. The passengers also stated that these roadside service centers have created job opportunities in the region. They also have been effective in providing security of the roads.

scholarly journals Decision support system based in AHP method to selection vendors of clinical laboratorys inputs

2019 ◽  
Vol 10 (5) ◽  
pp. 1536
Author(s):  
André Andrade Longaray ◽  
Anderson Picua Gonçalves ◽  
Vilmar Gonçalves Tondolo ◽  
Rosana Tondolo ◽  
Catia Maria dos Santos Machado
Keyword(s):  
Selection Process ◽  
Clinical Analysis ◽  
Correct Selection ◽  
Analytic Hierarchy ◽  
Organizational Goals ◽  
Analysis Laboratory ◽  
Hierarchy Process ◽  
The City ◽  
Selection Of

In a competitive marketing scenario, the purchasing area contributes significantly to the achievement of organizational goals. Its mission is to identify the competitive needs of products and services, becoming responsible for the timely delivery, costs optimization and quality. Within shopping, a correct selection of vendors is important for this to happen. From this perspective, the present study aims to develop a model that assists in the vendors’ selection process. This way, a case study was carried out in a clinical analysis laboratory located in the city of Rio Grande, where the AHP (Analytic Hierarchy Process) was used as an intervention tool. The development process consisted in three stages. The first one aimed at structuring the model, in which the hierarchy of criteria was defined. In the second step, the judgments were carried out and the relative weights for each criterion and subcriterion were calculated. Finally, the third step aimed at applying the model developed in a purchasing process. The model was tested in a selection process that involved the evaluation of three vendors of a laboratorial input, in order to identify which one met the demands of the organization. The result obtained with its use was considered satisfactory, this way, the model was approved by the manager who participated in the structuring process of the AHP hierarchy.

scholarly journals Influence of Hydrogeological Investigation’s Accuracy on Technology of Shaft Sinking and Design of Shaft Lining—Case Study from Southern Poland

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2050
Author(s):  
Kajetan d’Obyrn ◽  
Paweł Kamiński ◽  
Jacek Motyka
Keyword(s):  
Rock Mass ◽  
Geological Data ◽  
Geotechnical Investigation ◽  
Coal Basin ◽  
Southern Poland ◽  
Key Factor ◽  
Shaft Sinking ◽  
Shaft Lining ◽  
Selection Of

Accuracy of hydrogeological and geotechnical investigation in place of shaft sinking is a key factor for selection of sinking method and design of the shaft lining. The following work presents the influence of the rising level of accuracy of geological data gathered in the area of shaft sinking in the Silesian Coal Basin and technical projects of shaft lining and technology of its sinking, which have been changing over the years. The initial project of the shaft was repeatedly modified. Each modification eventuated in rising requirements for the shaft lining, such as increasing its thickness or changing concrete class. It has become necessary to use additional methods of reinforcing rock mass around the shaft.

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