Evaluation and Comparison of Two Design for Assembly Methods: Subjectivity of Information Inputs

2011 ◽  
Author(s):  
Eric Owensby ◽  
Aravind Shanthakumar ◽  
Vikrant Rayate ◽  
Essam Namouz ◽  
Joshua D. Summers
Keyword(s):  
Consumer Products ◽  
Bench Mark ◽  
Design For Assembly ◽  
Assembly Time ◽  
Subjective Information ◽  
The Times ◽  
Types Of Information ◽  
Information Amount ◽  
Complexity Algorithm ◽  
Assembly Software

This paper presents a comparison study on two design for assembly (DFA) tools, Boothroyd and Dewhurst’s Design for Manufacturing and Assembly software and the Mathieson-Summers connective-complexity algorithm, focusing on the amount of information required from the designer to complete the analysis and the subjectivity of this information. The Boothroyd Dewhurst software requires the user to answer a set of questions about each part and how it is assembled to estimate an assembly time, assembly cost, and to suggest design improvements. The connective-complexity method predicts assembly times based on the physical connectivity between parts within an assembly. The methods are applied to three consumer products and evaluated and compared through five criteria: approximate time to conduct the analysis, predicted assembly time, amount of required input information, amount of subjective information, and number of redesign features provided to the user. The results show that the DFMA software requires the user to go through eight types of information answering a total of forty nine questions per part. Sixteen of these questions are based on subjective information making the analysis nearly a third subjective. The connectivity method requires only two types of information and a total of five questions per part to complete the analysis, none of it being subjective. The predicted assembly times from the connective-complexity DFA method ranged from 13.11% to 49.71% lower than the times predicted by the DFMA software. The results from this comparison can be used to bench mark DFA methods so that their weaknesses can be identified and improved.

scholarly journals Mapping Urbanization as an Anthropedogenetic Process: A Section through the Times of Urban Soils

2020 ◽  
Vol 5 (2) ◽  
pp. 262-279 ◽  
Author(s):  
Antoine Vialle ◽  
Mario Giampieri
Keyword(s):  
Environmental History ◽  
Urban Areas ◽  
Urban Soils ◽  
Dynamic Vision ◽  
Strategic Role ◽  
Spatio Temporal ◽  
Map Series ◽  
The Times ◽  
Types Of Information ◽  
Ecological Transition

Current trends of spatial planning policies give a strategic role to soils, the multifunctionality of which must be considered as a crucial driver facing cities’ forthcoming social-ecological transition. However, soils within urban areas are insufficiently studied as a long-term record of environmental history and heavy anthropization. This article investigates the extreme qualitative variability of urban soils by presenting a conceptual model and cartographic workflow highlighting soil evolution processes as a value which co-variates with urbanization. Based on a case study in West Lausanne (Switzerland), the layers and map series of an atlas underscore the applicability of different types of information and spatial analysis for documenting the influence of anthrosediments and land cover changes. Combined with empirical profile descriptions, such a consolidated concept map defines a template, in the form of a complex spatio-temporal figure, on which to apply the state factor approach. Instead of using a simple spatial transect or gradient, the increasing anthropic dominance over original landscape conditions is explained using a section through time. An urban anthroposequence consequently retraces contrasting soil development pathways as a coherent bundle of historical trajectories. Such a narrative integrates various facets of land use, including one-off construction techniques and recurring maintenance practices, planning tools, and morphologies, into a specific ‘project for the ground’ which brought forth the mixed mesh of the Swiss Plateau ‘cityterritory.’ Ultimately, the dynamic vision conveyed by these intertwined soil–urbanization coevolution trajectories outlines opportunities for the regeneration of the resource deposit made up of both West Lausanne’s urban fabric and its soils as a palimpsest.

Reduction of Acquisition Time Through New Design for Assembly Heuristics

1994 ◽  
Author(s):  
Robert H. Sturges ◽  
David O. Hunt
Keyword(s):  
Product Design ◽  
Information Flow ◽  
Acquisition Time ◽  
Design For Assembly ◽  
Automatic Processes ◽  
Acquisition Process ◽  
Assembly Time ◽  
New Information ◽  
Component Orientation ◽  
Time Averages

Abstract Rearranging component positions and orientations inside products can reduce the acquisition times associated with handling distance and component orientation. Modeling the acquisition process with an information-based Design for Assembly methodology identifies and quantifies acquisition difficulty for manual and automatic processes. Heuristics based on evaluations of acquisition difficulty guide the relocation and reorientation of components inside the product to reduce assembly time. Since acquisition time averages one third of the total assembly time, significant improvements are shown to be feasible. A new information flow from downstream assembly issues into product design is demonstrated.

scholarly journals Usulan Perbaikan Peracangan Produk Smart Light Menggunakan Metode Design for Assembly Boothroyd-Dewhurst

2018 ◽  
Vol 1 (3) ◽  
Author(s):  
Arief Irfan Syah Tjaja ◽  
Rochmat Puji Astomo ◽  
Rispianda
Keyword(s):  
Design For Assembly ◽  
Assembly Process ◽  
Lamp Product ◽  
Design Efficiency ◽  
Street Lighting ◽  
Good Design ◽  
Assembly Time ◽  
Light Product ◽  
Led Lights ◽  
Design Result

ABSTRACTSmart Lamp product is a street lighting product which developed by PT X with LED lights concept. The design of Smart Light product is found to be slightly violate the terms of good design to the assembly process proposed by Boothroyd-Dewhurst as there is a component with sharp side, too much for using fastener, difficult fastener installation because the component is blocked and so forth. Existing design efficiency of Smart Light product is based on a calculation using the Boothroyd-Dewhurst table is 7.63% with total assembly time for 1149.1 seconds while the proposed design efficiency is 15.52% with total assembly time is 539.84 seconds. The changes of the design result reduction of the estimated product cost from Rp1.831.721, - and the BEP in 1482 products on existing product to Rp1.732.609, - and the BEP in 1283 products on proposed product.Kata kunci: design efficiency, assembly time, estimated cost, break event point (BEP).ABSTRAKProduk Smart Light adalah merupakan sebuah produk lampu penerangan jalan yang dikembangkan oleh PT X dengan konsep lampu LED. Rancangan produk Smart Light ini ternyata tidak sedikit melanggar ketentuan-ketentuan perancangan yang baik untuk proses perakitan yang dikemukakan oleh Boothroyd-Dewhurst seperti terdapat komponen yang memiliki bagian yang tajam, penggunaan fastener yang terlalu banyak, pemasangan fastener yang sulit karena komponen terhalang dan sebagainya. Efisiensi desain existing produk Smart Light ini berdasarkan pada perhitungan menggunakan tabel Boothroyd-Dewhurst adalah 7,63% dengan waktu perakitan total selama 1149,1 detik sedangkan efisiensi desain usulan adalah 15,52% dengan waktu perakitan total selama 539,84 detik. Perubahan rancangan desain mengakibatkan pengurangan pada estimasi biaya produk dari Rp1.831.721,- dan break event point (BEP) pada produk ke 1482 untuk produk existing menjadi Rp1.732.609,- dan BEP pada produk ke 1283 untuk produk usulan..Keywords: efisiensi desain, waktu perakitan, estimasi biaya, break event point

Application of an Information-Based Design for Assembly Theory to Assembly Workstation Design

1993 ◽  
Author(s):  
David O. Hunt ◽  
Robert H. Sturges
Keyword(s):  
Problem Formulation ◽  
Mixed Integer ◽  
Computational Time ◽  
Design For Assembly ◽  
Assembly Time ◽  
Aspect Ratios ◽  
Workstation Design ◽  
Orientation Time ◽  
Np Hard Problem ◽  
Assembly Tasks

Abstract An effective presentation of components at the workstation can have a significant impact in reducing assembly time. Our goal is to reduce the assembly time by optimization of the component presentation. The assembly factors recognized in Design for Assembly theory as relevant to both parts acquisition and assembly workstation layout are recognition, orientation, weight, and handling distance. This study considers a single manual assembler at an assembly station, with the components in rectangular bins of differing sizes and aspect ratios. Ninety degree rotations are allowed for minimizing potential handling distance. The assembly task is modelled with multiple assembly points representing the final location of the components. Components can be preoriented or random in the bins, with preorientation removing the recognition and orientation time penalties. The problem formulation employs Mixed Integer Non-Linear Programming (MINLP), and numerical evidence suggests an np-hard problem. Heuristic methods control computational time to practical levels for realistic assembly tasks. Our results show that numerical optimization of assembly workstation layout can reduce the expected level of difficulty over random or manual workstation design methods.

Identifying Failure Modes and Effects Through Design for Assembly Analysis

2018 ◽  
Author(s):  
Phyo Htet Hein ◽  
Nate Voris ◽  
Jiaying Dai ◽  
Beshoy W. Morkos
Keyword(s):  
Failure Mode ◽  
Failure Modes ◽  
Estimation Method ◽  
Time Estimation ◽  
Handling Time ◽  
Insertion Time ◽  
Design For Assembly ◽  
Assembly Time ◽  
Time Required ◽  
The Ideal

Design for Assembly (DFA) time estimation method developed by G. Boothroyd and P. Dewhurst allows for estimating the assembly time of artifacts based on analysis of component features using handling and insertion tables by an assembler, who is assumed to assemble the artifact one-part-at-a-time. Using the tables, each component is assigned an assembly time which is based on the time required for the assembler to manipulate (handling time) and the time required for it to interface with the rest of the components (insertion time). Using this assembly time and the ideal assembly time (i.e. the absolute time it takes to assemble the artifact, assuming each component takes the ideal time of three seconds to handle and insert), this method allows to calculate the efficiency of a design’s assembly process. Another tool occasionally used in Design for Manufacturing (DFM) is Failure Modes and Effects Analysis (FMEA). FMEA is used to evaluate and document failure modes and their impact on system performance. Each failure mode is ranked based on its severity, occurrence, and detectability scores, and corrective actions that can be taken to control risk items. FMEA scores of components can address the manufacturing operations and how much effort should be put into each specific component. In this paper, the authors attempt to answer the following two research questions (RQs) to determine the relationships between FMEA scores and the DFA assembly time to investigate if part failure’s severity, occurrence, and detectability can be estimated if handling time and insertion time are known. RQ (1): Can DFA metrics (handling time and insertion time) be utilized to estimate Failure Mode and Effects scores (severity, occurrence, and detectability)? RQ (2): How does each response metric relate to predictor metrics (positive, negative, or no relationship)? This is accomplished by performing Boothroyd and Dewhurst’s DFA time estimation and FMEA on select set of simple products. Since DFA metrics are based on combination of designer’s subjectivity and part’s geometric specifications and FMEA scores are based only on designer’s subjectivity, this paper attempts to estimate part failure severity, occurrence, and detectability less subjectively by using the handling time and insertion time. This will also allow for earlier and faster acquisition of potential part failure information for use in design and manufacturing processes.

scholarly journals Pelatihan Penyusunan Laporan Keuangan dan Pajak Entitas yang Tidak Menyelenggarakan Sistem Akuntansi Bagi Guru SMK dan SMA Pengajar Akuntansi di Kota Pontianak

2019 ◽  
Vol 2 (1) ◽  
pp. 147
Author(s):  
Zulham Al Farizi ◽  
Susan Andriana ◽  
Linda Suherma
Keyword(s):  
Information Technology ◽  
Information Systems ◽  
Accounting Information ◽  
Financial Statements ◽  
Financial Statement ◽  
Accounting Information Systems ◽  
Available Technology ◽  
The Times ◽  
Types Of Information ◽  
Tax Reporting

This activity aims to provide a basic theory of how to compile financial statements for entities that do not hold accounting information systems, provide skills to utilize available technology to conduct financial statement preparation, and introduce the types of information technology used in tax reporting. Currently the industrial world has entered the Industrial era 4.0 graduates from education providers must have technology-based competencies in order to be able to have competitiveness and keep up with the times. Industries that are running domestically, should be able to be carried out and carried out by local workers by increasing their capacity. So that they are not just occupying low positions

scholarly journals Revealing lost 16th-century royal emblems on two Andrea Amati’s violins using XRF scanning

2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Marie Radepont ◽  
Jean-Philippe Échard ◽  
Matthias Ockermüller ◽  
Hortense de la Codre ◽  
Oulfa Belhadj
Keyword(s):  
Spatial Distribution ◽  
Research Question ◽  
Spectroscopic Technique ◽  
16Th Century ◽  
Philip Ii ◽  
The Past ◽  
Wide Range ◽  
Approach Method ◽  
The Times ◽  
Types Of Information

Abstract A key issue in understanding artefacts from the past is the loss of readability of the signs they may have borne. The two 16th-century musical instruments studied here—rare Italian violins made by Andrea Amati (c.1505-1577) in Cremona—bear remains of painted heraldic emblems, which are barely legible and thus remained undeciphered until today. They are exemplary representatives of this research question, indeed combining various types of losses, which are widely encountered on archaeological artefacts: they are now incomplete (parts are missing, surfaces are abraded) and the paint matter itself, of which the signs are made, has altered. In this study, the complete original outlines and geometrical subdivisions of the shields are deduced from calculations based on the conventional heraldic construction practices of the times. Also, in situ elemental imaging of the shield areas—here using scanning X-ray fluorescence (XRF) spectroscopy— brings two types of information: (i) the nature of pigments, allowing to deduce the initial colours of the paints not discernable to the eye, whether abraded or discoloured; (ii) the spatial distribution of these pigments and colours inside the shield. This multi-approach method leads to the unprecedented revelation of a combination of symbols (tinctures of fields, emblematic ornaments, and their relative spatial distribution), all having meanings in heraldic language. The reconstructed coats of arms appear to be pointing to a very specific nine-year period (1559–1568) of the life of the queen Elisabeth (Isabel) of Valois, spouse of Philip II of Spain. We suggest that this approach, combining an imaging spectroscopic technique and a geometrical study of remaining decors, here providing new insights into the musical history at the Court of Spain, may be used to enhance the readability of a wide range of writings, signs and symbols on artefacts from the past.

The Eclipsing Binary WX Eridani

1979 ◽  
Vol 46 ◽  
pp. 385
Author(s):  
M.B.K. Sarma ◽  
K.D. Abhankar
Keyword(s):  
Light Curve ◽  
Spectral Type ◽  
Orbital Period ◽  
Primary Component ◽  
Light Curves ◽  
Absorption Feature ◽  
Primary Star ◽  
Eclipsing Binary ◽  
The Times ◽  
Phase Angles

AbstractThe Algol-type eclipsing binary WX Eridani was observed on 21 nights on the 48-inch telescope of the Japal-Rangapur Observatory during 1973-75 in B and V colours. An improved period of P = 0.82327038 days was obtained from the analysis of the times of five primary minima. An absorption feature between phase angles 50-80, 100-130, 230-260 and 280-310 was present in the light curves. The analysis of the light curves indicated the eclipses to be grazing with primary to be transit and secondary, an occultation. Elements derived from the solution of the light curve using Russel-Merrill method are given. From comparison of the fractional radii with Roche lobes, it is concluded that none of the components have filled their respective lobes but the primary star seems to be evolving. The spectral type of the primary component was estimated to be F3 and is found to be pulsating with two periods equal to one-fifth and one-sixth of the orbital period.

High-Voltage Scanning Electron Microscopy

1970 ◽  
Vol 28 ◽  
pp. 6-7
Author(s):  
J. M. Cowley
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Scanning Transmission Electron Microscopy ◽  
Wave Optics ◽  
Contrast Effects ◽  
Transmission Electron ◽  
Mode Of Operation ◽  
Scanning Transmission ◽  
Types Of Information ◽  
Voltage Scanning

The comparison of scanning transmission electron microscopy (STEM) with conventional transmission electron microscopy (CTEM) can best be made by means of the Reciprocity Theorem of wave optics. In Fig. 1 the intensity measured at a point A’ in the CTEM image due to emission from a point B’ in the electron source is equated to the intensity at a point of the detector, B, due to emission from a point A In the source In the STEM. On this basis it can be demonstrated that contrast effects In the two types of instrument will be similar. The reciprocity relationship can be carried further to include the Instrument design and experimental procedures required to obtain particular types of information. For any. mode of operation providing particular information with one type of microscope, the analagous type of operation giving the same information can be postulated for the other type of microscope. Then the choice between the two types of instrument depends on the practical convenience for obtaining the required Information.

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