Reduction of Impact Noise at the Design Stage: A Specific Case Study

1972 ◽  
Vol 186 (1) ◽  
pp. 391-399
Author(s):  
M. A. Salter ◽  
B. Downs ◽  
G. R. Wray
Keyword(s):  
Experimental Approach ◽  
Design Stage ◽  
Experimental Investigations ◽  
Theoretical Treatment ◽  
Impact Noise ◽  
Design Changes ◽  
Machine Cycle ◽  
Mechanism Of Impact ◽  
The Impact

A case study is made on the tack driving assembly of a boot and shoe lasting machine, and relates to the impact noise occurring during part of the machine cycle. Much of the noise is radiated due to vibrations at several frequencies of the tack driver lifting lever, which is excited by the direct application of impacts during the tack driving process. An experimental approach in applying noise reduction principles to various components of the assembly has been preferred to a more complex theoretical treatment, since the identification of the mechanism of impact noise generation and its subsequent abatement is directly relevant to most machine designers faced with the possibility of impact noise problems in other types of machinery. Small design changes, based on the knowledge gained from the experimental investigations, have resulted in noise reductions from 10 to 14 dB being achieved.

Case Study: Laboratory and Field Measurements for Evaluating the Weighted Reduction in Impact Noise Associated with Floor Coverings

2002 ◽  
Vol 9 (2) ◽  
pp. 151-162 ◽  
Author(s):  
Jorge Patrício
Keyword(s):  
Field Measurements ◽  
Design Stage ◽  
Sound Insulation ◽  
Horizontal Beam ◽  
Impact Noise ◽  
Loudness Level ◽  
Floor Coverings ◽  
The Difference ◽  
Study Laboratory

In order that impact sound insulation in buildings complies with national regulations, the use of floor coverings needs to be considered, either at the design stage, or as a corrective measure. The improvement of impact sound insulation for floor coverings shown in marketing literature, comes from laboratory tests, expressed as the difference between the values of bare and covered floor noise insulation indices, calculated in accordance with what is prescribed in standard EN ISO 717/2. However, the values of the improvement for the same product are sometimes very different from laboratory to on-site conditions. This problem is more acute for buildings with non-homogenous floors such as beam-block. This case study presents some tests performed on identical horizontal beam-block slabs, in the laboratory and on site, using the same floor coverings. Discrepancies in the values obtained for the characterisation of each floor covering are observed. Assuming that part of the problem could be linked to the type of index used, a comparison is made using the following metrics: ΔdB(A); ΔLn,w (or ΔL3n,w – when on site); and the difference of Loudness Level.

Reduction of Noise at the Design Stage: A Case Study of a Lightly Loaded Assembly

1969 ◽  
Vol 184 (1) ◽  
pp. 593-614 ◽  
Author(s):  
M. A. Satter ◽  
B. Downs ◽  
G. R. Wray
Keyword(s):  
Analytical Study ◽  
Design Stage ◽  
Acoustic Absorption ◽  
Noise Generation ◽  
Noise Emission ◽  
Design Changes ◽  
Damping Materials ◽  
Lower Noise ◽  
Made In

An experimental and analytical study is made of the noise emission from the drawroll assembly of a textile draw-twisting machine. As an alternative to resorting to acoustic absorption techniques or the use of expensive high damping materials, investigations are made into the basic method of noise generation in the assembly. This leads to the incorporation of small design changes and the significantly lower noise emission thereby achieved is compared with the original emission. Aimed at the machine designer, the presentation is made in a straightforward, non-mathematical fashion.

Reliability-Informed Economic and Energy Evaluation for Design for Remanufacturing: A Case Study on a Hydraulic Manifold

2021 ◽  
Author(s):  
Venkat P. Nemani ◽  
Jinqiang Liu ◽  
Navaid Ahmed ◽  
Adam Cartwright ◽  
Gül E. Kremer ◽  
...  
Keyword(s):  
Life Cycles ◽  
Design Stage ◽  
Design Strategies ◽  
Early Design Stage ◽  
Energy Evaluation ◽  
Design For Remanufacturing ◽  
Design Changes ◽  
Development Evaluation ◽  
Field Reliability

Abstract Design for Remanufacturing (DfRem) is an attractive approach for sustainable product development. Evaluation of DfRem strategies, from both economic and environmental perspectives, at an early design stage can allow the designers to make informed decisions when choosing the best design option. Studying the long-term implications of a particular design scenario requires quantifying the benefits of remanufacturing for multiple life cycles while considering the reliability of the product. In addition to comparing designs on a one-to-one basis, we find that including reliability provides a different insight into comparing design strategies. We present a reliability-informed cost and energy analysis framework that accounts for product reliability for multiple remanufacturing cycles within a certain warranty policy. The variation of reuse rate over successive remanufacturing cycles is formulated using a branched power-law model which provides probabilistic scenarios of reusing or replacing with new units. To demonstrate the utility of this framework, we use the case study of a hydraulic manifold, which is a component of a transmission used in some agricultural equipment, and use real-world field reliability data to quantify the transmission’s reliability. Three design improvement changes are proposed for the manifold and we quantify the costs and energy consumption associated with each of the design changes for multiple remanufacturing cycles.

scholarly journals Energy Efficiency Analysis in Buildings using Dynamic Simulations

2017 ◽  
Vol 2 (5) ◽  
pp. 1
Author(s):  
Elena Eftimie
Keyword(s):  
Energy Efficiency ◽  
Energy Performance ◽  
Design Stage ◽  
Dynamic Simulations ◽  
Heating Systems ◽  
Use Phase ◽  
Comfort Parameters ◽  
The Impact

This paper proposes an analysis of factors that have a significant impact on energy efficiency in buildings. Thus, as a first objective proposes an analysis of the impact of rehabilitation and modernization of buildings in view of their energy performance improvement. A second followed objective consisted of the study of some production and use thermal energy systems in order to increase the thermal comfort. Based on a case study, this paper provides the opportunity for comparative analyses both among different insulation materials for buildings and among different heating systems. Determination of energy consumption for space heating and of the building comfort parameters was achieved using dynamic simulations by means of TRNSYS program; it was envisaged that the assessment of energy efficiency in buildings, the design stage or before their rehabilitation, is more economical than finding solutions in the use phase of buildings.

BIM-based model for quantifying the design change time ripple effect

2017 ◽  
Vol 44 (8) ◽  
pp. 626-642 ◽  
Author(s):  
Valeh Moayeri ◽  
Osama Moselhi ◽  
Zhenhua Zhu
Keyword(s):  
Construction Projects ◽  
Total Duration ◽  
Information Modeling ◽  
Ripple Effect ◽  
Project Schedule ◽  
Design Changes ◽  
Building Information ◽  
Quantification Model ◽  
The Impact

Design changes by owners are common to many construction projects and can cause severe delays if owners do not consider that a change in one part of the project may cause a series of changes in other parts of that project. The impact of a changed component on other unchanged components is known as the “change ripple effect”. To efficiently manage design changes, the ripple effect should be quantified and impact evaluated. This paper presents a building information modeling (BIM)-based quantification model to quantify the ripple effect of owner-requested design changes. The developed model calculates the impact of design changes and their ripple effect on a project’s total duration. After analyzing the ripple effect over time, the model updates the project schedule accordingly. To demonstrate its usefulness and illustrate its essential features, the model is applied to a case study.

scholarly journals Influence of Single-Phase Solar Photovoltaic Systems on Total Harmonic Distortion: A Case Study

2018 ◽  
Vol 12 (2) ◽  
pp. 607
Author(s):  
Chin Kim Gan ◽  
Sara Ragab Mahmoud ◽  
Kyairul Azmi Baharin ◽  
Mohd Hendra Hairi
Keyword(s):  
Single Phase ◽  
Harmonic Distortion ◽  
Total Harmonic Distortion ◽  
Photovoltaic System ◽  
Design Stage ◽  
Small Scale ◽  
Photovoltaic Systems ◽  
Solar Photovoltaic ◽  
The Impact

<span>The installation of small-scale solar photovoltaic system has recently gaining popularity in Malaysia mainly driven by the Feed-in Tariff scheme. Given its relatively small generation capacity, the single-phase solar inverters are not required to comply with power quality standard. Neverthelss, the impact of small-scale solar system on the grid could become significant when the penetration is increasing over the years. In this regard, this paper presents a case study on the influence of single-phase grid-connected solar photovoltaic systems on the total harmonic distortion for current at the point of common coupling. Field measurements have been carried out for a total of 12 single-phase solar systems which were installed at three different locations at Universiti Teknikal Malaysia Melaka. Detailed analyses have been performed to characterize the aggregated current harmonic performance for the overall system.  The findings from the presented case study suggest that the current quality from the inverter is highly dependent on the level of inverter output. Hence, the proper selection of the array-to-inverter ratio at the system design stage could greatly improve the overall total harmonic performance performance for current.</span><span>The installation of small-scale solar photovoltaic system has recently gaining popularity in Malaysia mainly driven by the Feed-in Tariff scheme. Given its relatively small generation capacity, the single-phase solar inverters are not required to comply with power quality standard. Neverthelss, the impact of small-scale solar system on the grid could become significant when the penetration is increasing over the years. In this regard, this paper presents a case study on the influence of single-phase grid-connected solar photovoltaic systems on the total harmonic distortion for current at the point of common coupling. Field measurements have been carried out for a total of 12 single-phase solar systems which were installed at three different locations at Universiti Teknikal Malaysia Melaka. Detailed analyses have been performed to characterize the aggregated current harmonic performance for the overall system.  The findings from the presented case study suggest that the current quality from the inverter is highly dependent on the level of inverter output. Hence, the proper selection of the array-to-inverter ratio at the system design stage could greatly improve the overall total harmonic performance performance for current.</span>

Reduction of Rotating Imbalance Measurement Variation Resulting From Test Apparatus Redesign

2005 ◽  
Author(s):  
Shannon K. Sweeney ◽  
Kenneth J. Fisher
Keyword(s):  
Applied Research ◽  
Technology Development ◽  
Test Apparatus ◽  
Technology Application ◽  
Measurement Variation ◽  
Research Activities ◽  
Design Changes ◽  
Rotor Assembly ◽  
The Impact

A case study is presented describing an undergraduate MET capstone design project aimed at reducing the measurement variation of rotating imbalance during the testing of vehicular powertrain products. Primary focus involved the redesign of the rotor assembly interfacing the balance machine and the product. The project entailed the implementation of innovative statistical methods discovered during the ongoing applied research activities of the faculty advisor. These methods were conveyed to the students who were charged with their application during the project. Tasks assigned to the students included the evaluation of existing measurement variation, identification of sources of measurement variation, redesign of the test apparatus to reduce the sources of variation, and quantification of the impact of redesign on measurement variation. The redesign of the rotor assembly and the marked reduction in measurement variation resulting from the design changes are described within the paper. The case study provides an example of the successful integration of technology development derived during the advising faculty’s innovative applied research with technology application by students during a successful undergraduate capstone student design experience.

Factors Affecting Ship Design and Construction Lead Time and Cost

2005 ◽  
Vol 21 (03) ◽  
pp. 186-194
Author(s):  
Howard Moyst ◽  
Biman Das
Keyword(s):  
Design Process ◽  
Lead Time ◽  
Ship Design ◽  
Start Time ◽  
Design Quality ◽  
Improve Design ◽  
Design Changes ◽  
The Impact ◽  
Design And Construction

This paper reviews a ship design and construction case study in the context of the published literature on the design process and its impact on construction. The objective was to explore the factors that impact design and construction lead time and cost. Design and construction managers constantly experience pressure to accelerate the construction start time in an environment characteristic of frequent design changes and rework. Often the construction of the first ships of a series will aggressively overlap the design phase. This investigation assessed a case study that illustrated that as the degree of overlap between design and construction increases, design changes increased ship construction costs and duration. This negates the advantage of trying to reduce lead time by overlapping phases. Before strategies of overlapping are utilized, shipbuilders need to better understand the details of the design process and its integration with other functions to improve design quality and reduce the impact of design changes on manufacturing and construction. It is recommended that when overlapping strategies are considered, design changes and their impact on construction be factored into the decision. A better strategy would be to eliminate design quality issues and design and construction rework.

scholarly journals Evaluating the Impacts of Courtyards on Educational Buildings, Case Study in the University of Sharjah

2021 ◽  
Vol 14 (1) ◽  
pp. 141
Author(s):  
Iman Ibrahim ◽  
Nadia Al Badri ◽  
Emad Mushtaha ◽  
Osama Omar
Keyword(s):  
Experimental Approach ◽  
Simulation Analysis ◽  
Social Aspects ◽  
Traditional Architecture ◽  
Interior Spaces ◽  
Middle East Countries ◽  
Before And After ◽  
The University ◽  
The Impact

Courtyards are traditionally associated with the Middle East countries, where climate and culture have given shape to a particular type of traditional architecture. The study evaluates the environmental and social impacts of courtyards in an educational building integrated with occupant’s interaction behavior. The case study of the University of Sharjah includes eight different courtyards unoccupied for many years, in different locations around the building with various proportions; the objectives were to examine and evaluate the impact of redesigning the interior spaces of the courtyards in terms of environmental and social aspects. The inductive and experimental approach were adopted in this research, where two surveys were conducted for the occupants, before and after the design applications. In addition to the use of eco-tech software for simulation. In conclusion, the results of surveys and interviews clarified the problem and offered some recommendations and simulation analysis provided recommendations and guidelines for designers.

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