Effect of Tuned Spring on Vibration Control Performance of Modified Liquid Column Ball Damper

This paper reports the theoretical findings of the new modified type of tuned liquid column ball damper (TLCBD), called a tuned liquid column ball spring damper (TLCBSD). In this new modified form, the ball inside the horizontal section of the damper is attached to the spring. Furthermore, two types of this modified version are proposed, known as a tuned liquid column ball spring sliding damper (TLCBSSD) and a tuned liquid column ball spring rolling damper (TLCBSRD). In the former, the rotational motion of the ball attached to the spring is restricted, whereas in the latter, the ball attached to the spring can translate as well as rotate. Mathematical models and optimum design parameters are formulated for both types. The performance of these new modified damper versions is assessed numerically and subjected to harmonic, seismic, and impulse loadings. The results show that the performance of the newly proposed dampers is relatively better than traditional TLCBDs in harmonic and seismic excitations. The peak response reduction soon after the impact load becomes zero is comparatively better in TLCBSDs over TLCBDs. Overall, the newly proposed passive vibration control devices performed excellently in structure response reduction over TLCBDs.

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INFLUENCE OF RARE-EARTH ON THE MICROSTRUCTURE AND MECHANICAL PROPERTIES OF HIGH MANGANESE STEEL UNDER IMPACT LOAD

Acta Metallurgica Slovaca ◽

10.12776/ams.v25i3.1309 ◽

2019 ◽

Vol 25 (3) ◽

pp. 158

Author(s):

Nam Duong Nguyen ◽

Nguyen Duong Nguyen ◽

Khanh Mai Pham

Keyword(s):

Mechanical Properties ◽

Rare Earth ◽

Impact Strength ◽

Impact Load ◽

Manganese Steel ◽

High Manganese ◽

High Manganese Steel ◽

Microstructure And Mechanical Properties ◽

The Impact ◽

Better Than

In this paper, the influence of rare earth (RE) on the microstructure and mechanical properties of austenitic high manganese steel (HMnS) Mn15Cr2V were investigated. The results showed that the microstructure, hardness and impact strength of RE modification sample is finer and better than non-modified sample. Under the effect of impact load, the hardness and the depth of the work-hardening layer of the modified steel was higher than that of the non-modified steel, thereby, the value of microhardness in the surface of the modified sample was 420 HV while it was only 395 HV in the non-modified sample. The value of the impact strength of the modified sample was up to 132J/cm2 compared to the non-modified sample is only 115J/cm2. Moreover, after impact load, the austenite nanoparticles had been found out on the surface of this steel, this is the cause of the increasing of mechanical properties in this steel.

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Energy-saving investigation of vacuum reactive distillation for the production of ethyl acetate

Chemical Product and Process Modeling ◽

10.1515/cppm-2021-0060 ◽

2022 ◽

Vol 0 (0) ◽

Author(s):

Ganesh N. Patil ◽

Nirmala Gnanasundaram

Keyword(s):

Ethyl Acetate ◽

Reactive Distillation ◽

Cooling Water ◽

Design Parameters ◽

Total Annual Cost ◽

Operating Pressure ◽

Cooling Water Temperature ◽

Pressure Swing ◽

The Impact ◽

Better Than

Abstract Ethyl acetate (EtAc) reactive distillation (RD) configurations often use atmospheric pressure, and this operating pressure can be reduced further to conserve energy based on the condenser cooling water temperature. Using the Aspen Plus simulator, two proposed configurations, RD column with stripper and pressure swing reactive distillation (PSRD), were simulated at lower operating pressure. The impact of RD column operating pressure on total energy usage and total annual cost (TAC) was studied. All design parameters were optimized using sequential iterative optimization procedures and sensitivity analysis to minimize the energy cost while maintaining the required product purity at 99.99%. The simulation results showed that the RD column with a stripper is better than PSRD with a saving of 23.17% in TAC and 31.53% in the specific cost of EtAc per kg. Compared to literature results, the proposed configurations have lower reboiler duty requirements and lower cost per kg of EtAc.

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VIBRATION CONTROL OF SLENDER STRUCTURES WITH OPTIMIZED LIQUID COLUMN VIBRATION ABSORBERS

10.26678/abcm.cobem2019.cob2019-0470 ◽

2019 ◽

Author(s):

Jéssica Carolina Barbosa Vieira ◽

Thiago da Silva ◽

Carlos Alberto Bavastri

Keyword(s):

Vibration Control ◽

Liquid Column ◽

Vibration Absorbers ◽

Slender Structures

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Advertising Media Impact in Consumer Buying Behavior

Journal of Balkumari College ◽

10.3126/jbkc.v8i0.29310 ◽

2019 ◽

Vol 8 ◽

pp. 54-56

Author(s):

Ashmita Dahal Chhetri

Keyword(s):

Consumer Behavior ◽

Young Male ◽

Electronic Media ◽

Buying Behavior ◽

Media Impact ◽

High Degree ◽

The Impact ◽

Buying Behaviors ◽

The Relationship ◽

Better Than

Advertisements have been used for many years to influence the buying behaviors of the consumers. Advertisements are helpful in creating the awareness and perception among the customers of a product. This particular research was conducted on the 100 young male and female who use different brands of product to check the influence of advertisement on their buying behavior while creating the awareness and building the perceptions. Correlation, regression and other statistical tools were used to identify the relationship between these variables. The results revealed that the relationship between media and consumer behavior is positive. The adve1tising impact on sales and there is positive and high degree relationship between advertising and consumer behavior. The impact on advertising of a product of electronic media is better than non-electronic media.

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Impact Load Buffering Method Based on Stress Wave Attenuation Principle

International Journal of Applied Mechanics ◽

10.1142/s1758825119500194 ◽

2019 ◽

Vol 11 (02) ◽

pp. 1950019 ◽

Cited By ~ 2

Author(s):

Lin Gan ◽

He Zhang ◽

Cheng Zhou ◽

Lin Liu

Keyword(s):

Stress Wave ◽

Wave Attenuation ◽

Impact Load ◽

Dynamics Simulation ◽

Scanning System ◽

Isolation Method ◽

Element Analysis ◽

System A ◽

High Emission ◽

The Impact

Rotating scanning motor is the important component of synchronous scanning laser fuze. High emission overload environment in the conventional ammunition has a serious impact on the reliability of the motor. Based on the theory that the buffer pad can attenuate the impact stress wave, a new motor buffering Isolation Method is proposed. The dynamical model of the new buffering isolation structure is established by ANSYS infinite element analysis software to do the nonlinear impact dynamics simulation of rotating scanning motor. The effectiveness of Buffering Isolation using different materials is comparatively analyzed. Finally, the Macht hammer impact experiment is done, the results show that in the experience of the 70,000[Formula: see text]g impact acceleration, the new buffering Isolation method can reduce the impact load about 15 times, which can effectively alleviate the plastic deformation of rotational scanning motor and improve the reliability of synchronization scanning system. A new method and theoretical basis of anti-high overload research for Laser Fuze is presented.

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A Rational Numerical Method for Simulation of Drop-Impact Dynamics of Oleo-Pneumatic Landing Gear

Applied Sciences ◽

10.3390/app11094136 ◽

2021 ◽

Vol 11 (9) ◽

pp. 4136

Author(s):

Rosario Pecora

Keyword(s):

Numerical Method ◽

Initial Conditions ◽

Impact Load ◽

Numerical Models ◽

Landing Gear ◽

Design Stage ◽

Impact Dynamics ◽

State Variables ◽

Adopted Model ◽

The Impact

Oleo-pneumatic landing gear is a complex mechanical system conceived to efficiently absorb and dissipate an aircraft’s kinetic energy at touchdown, thus reducing the impact load and acceleration transmitted to the airframe. Due to its significant influence on ground loads, this system is generally designed in parallel with the main structural components of the aircraft, such as the fuselage and wings. Robust numerical models for simulating landing gear impact dynamics are essential from the preliminary design stage in order to properly assess aircraft configuration and structural arrangements. Finite element (FE) analysis is a viable solution for supporting the design. However, regarding the oleo-pneumatic struts, FE-based simulation may become unpractical, since detailed models are required to obtain reliable results. Moreover, FE models could not be very versatile for accommodating the many design updates that usually occur at the beginning of the landing gear project or during the layout optimization process. In this work, a numerical method for simulating oleo-pneumatic landing gear drop dynamics is presented. To effectively support both the preliminary and advanced design of landing gear units, the proposed simulation approach rationally balances the level of sophistication of the adopted model with the need for accurate results. Although based on a formulation assuming only four state variables for the description of landing gear dynamics, the approach successfully accounts for all the relevant forces that arise during the drop and their influence on landing gear motion. A set of intercommunicating routines was implemented in MATLAB® environment to integrate the dynamic impact equations, starting from user-defined initial conditions and general parameters related to the geometric and structural configuration of the landing gear. The tool was then used to simulate a drop test of a reference landing gear, and the obtained results were successfully validated against available experimental data.

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Design of a Robust Memristive Spiking Neuromorphic System with Unsupervised Learning in Hardware

ACM Journal on Emerging Technologies in Computing Systems ◽

10.1145/3451210 ◽

2021 ◽

Vol 17 (4) ◽

pp. 1-26

Author(s):

Md Musabbir Adnan ◽

Sagarvarma Sayyaparaju ◽

Samuel D. Brown ◽

Mst Shamim Ara Shawkat ◽

Catherine D. Schuman ◽

...

Keyword(s):

Unsupervised Learning ◽

Recognition Task ◽

Single Layer ◽

Process Variations ◽

Spike Timing ◽

System Level ◽

Design Parameters ◽

Digital Pulse ◽

Neuromorphic System ◽

The Impact

Spiking neural networks (SNN) offer a power efficient, biologically plausible learning paradigm by encoding information into spikes. The discovery of the memristor has accelerated the progress of spiking neuromorphic systems, as the intrinsic plasticity of the device makes it an ideal candidate to mimic a biological synapse. Despite providing a nanoscale form factor, non-volatility, and low-power operation, memristors suffer from device-level non-idealities, which impact system-level performance. To address these issues, this article presents a memristive crossbar-based neuromorphic system using unsupervised learning with twin-memristor synapses, fully digital pulse width modulated spike-timing-dependent plasticity, and homeostasis neurons. The implemented single-layer SNN was applied to a pattern-recognition task of classifying handwritten-digits. The performance of the system was analyzed by varying design parameters such as number of training epochs, neurons, and capacitors. Furthermore, the impact of memristor device non-idealities, such as device-switching mismatch, aging, failure, and process variations, were investigated and the resilience of the proposed system was demonstrated.

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Locking down the Impact of New Zealand’s COVID-19 Alert Level Changes on Pets

Animals ◽

10.3390/ani11030758 ◽

2021 ◽

Vol 11 (3) ◽

pp. 758

Author(s):

Fiona Esam ◽

Rachel Forrest ◽

Natalie Waran

Keyword(s):

New Zealand ◽

Separation Anxiety ◽

National Surveys ◽

Normal Life ◽

Pet Owners ◽

Level 1 ◽

The Impact ◽

Better Than

The influence of the COVID-19 pandemic on human-pet interactions within New Zealand, particularly during lockdown, was investigated via two national surveys. In Survey 1, pet owners (n = 686) responded during the final week of the five-week Alert Level 4 lockdown (highest level of restrictions—April 2020), and survey 2 involved 498 respondents during July 2020 whilst at Alert Level 1 (lowest level of restrictions). During the lockdown, 54.7% of owners felt that their pets’ wellbeing was better than usual, while only 7.4% felt that it was worse. Most respondents (84.0%) could list at least one benefit of lockdown for their pets, and they noted pets were engaged with more play (61.7%) and exercise (49.7%) than pre-lockdown. Many respondents (40.3%) expressed that they were concerned about their pet’s wellbeing after lockdown, with pets missing company/attention and separation anxiety being major themes. In Survey 2, 27.9% of respondents reported that they continued to engage in increased rates of play with their pets after lockdown, however, the higher levels of pet exercise were not maintained. Just over one-third (35.9%) of owners took steps to prepare their pets to transition out of lockdown. The results indicate that pets may have enjoyed improved welfare during lockdown due to the possibility of increased human-pet interaction. The steps taken by owners to prepare animals for a return to normal life may enhance pet wellbeing long-term if maintained.

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Making Up 3D Bodies

Proceedings of the ACM on Computer Graphics and Interactive Techniques ◽

10.1145/3468779 ◽

2021 ◽

Vol 4 (2) ◽

pp. 1-9

Author(s):

Kiona Hagen Niehaus ◽

Rebecca Fiebrink

Keyword(s):

Software Tool ◽

The Body ◽

Design Parameters ◽

Artistic Practice ◽

Human Form ◽

Modeling Systems ◽

Exploratory Approach ◽

Disability Status ◽

High Level ◽

The Impact

This paper describes the process of developing a software tool for digital artistic exploration of 3D human figures. Previously available software for modeling mesh-based 3D human figures restricts user output based on normative assumptions about the form that a body might take, particularly in terms of gender, race, and disability status, which are reinforced by ubiquitous use of range-limited sliders mapped to singular high-level design parameters. CreatorCustom, the software prototype created during this research, is designed to foreground an exploratory approach to modeling 3D human bodies, treating the digital body as a sculptural landscape rather than a presupposed form for rote technical representation. Building on prior research into serendipity in Human-Computer Interaction and 3D modeling systems for users at various levels of proficiency, among other areas, this research comprises two qualitative studies and investigation of the impact on the first author's artistic practice. Study 1 uses interviews and practice sessions to explore the practices of six queer artists working with the body and the language, materials, and actions they use in their practice; these then informed the design of the software tool. Study 2 investigates the usability, creativity support, and bodily implications of the software when used by thirteen artists in a workshop. These studies reveal the importance of exploration and unexpectedness in artistic practice, and a desire for experimental digital approaches to the human form.

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Simulation Tests of a Cow Milking Machine—Analysis of Design Parameters

Processes ◽

10.3390/pr9081358 ◽

2021 ◽

Vol 9 (8) ◽

pp. 1358

Author(s):

Ewa Golisz ◽

Adam Kupczyk ◽

Maria Majkowska ◽

Jędrzej Trajer

Keyword(s):

Mathematical Model ◽

Simplified Model ◽

Design Parameters ◽

Degree Polynomial ◽

Fourth Degree ◽

Local Loss ◽

Linear Drag ◽

Milking Machine ◽

Machine Analysis ◽

The Impact

The objective of this paper was to create a mathematical model of vacuum drops in a form that enables the testing of the impact of design parameters of a milking cluster on the values of vacuum drops in the claw. Simulation tests of the milking cluster were conducted, with the use of a simplified model of vacuum drops in the form of a fourth-degree polynomial. Sensitivity analysis and a simulation of a model with a simplified structure of vacuum drops in the claw were carried out. As a result, the impact of the milking machine’s design parameters on the milking process could be analysed. The results showed that a change in the local loss and linear drag coefficient in the long milk duct will have a lower impact on vacuum drops if a smaller flux of inlet air, a higher head of the air/liquid mix, and a higher diameter of the long milk tube are used.

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