Selection of Part Orientation for Multi-Axis Hybrid Manufacturing Process

2009 ◽  
Author(s):  
Jianzhong Ruan ◽  
Jun Zhang ◽  
Frank Liou
Keyword(s):  
Manufacturing Process ◽  
Search Space ◽  
Deposition Process ◽  
Hybrid Manufacturing ◽  
Optimal Orientation ◽  
Multi Stage ◽  
Build Time ◽  
Speed Up ◽  
Computation Algorithm ◽  
Selection Of

In regular 3 axis layered manufacturing processes, the build direction is fixed throughout the process. Multi-axis laser (more than 3-axis motion) deposition process, the orientation of the part can affect the non-support buildability in the multi-axis hybrid manufacturing process. However, each orientation that satisfies the buildability and other constraints may not be unique. In this case, the final optimal orientation is determined based on build time. The build time computation algorithm for multi-axis hybrid system is presented in this paper. To speed up the exhaustive search for the optimal orientation, a multi-stage algorithm is developed to reduce the search space.

Improving Program Performance via Auto-Vectorization of Loops with Conditional Statements with GCC Compiler Setting

2013 ◽  
Vol 433-435 ◽  
pp. 1410-1414
Author(s):  
Qi Shen Zhu
Keyword(s):  
Search Space ◽  
Compiler Optimizations ◽  
Program Performance ◽  
Performance Improvements ◽  
Iterative Compilation ◽  
Conditional Statements ◽  
Speed Up ◽  
Performance Ability ◽  
Number Of Passes ◽  
Selection Of

The GCC is an auto-vectorization compiler across iterations of loops to parallelism data. Turning GCC compiler optimizations flags for auto-vectorization is a way to improve the performance ability, which is a popular approach to speed up program performance. However, there are many options in GCC compiler and selecting the best combination of these options to improve program performance through vectorization is non-trivial ( as the search space is very large ).In this work we focus on the selection of compiler transformations to auto-vectorize loops with conditional statements. The selection of compiler transformations is based on the correlation between program features, speed-up, and the analysis of the code generated and a small number of passes of iterative compilation. Our preliminary experimental results show that proposed technique attains performance improvements the best ~ 6x using loops in the TSVC benchmark suite on the state-of-the-art Intel Core i3 processor.

Integrated Process Planning for a Multiaxis Hybrid Manufacturing System

2010 ◽  
Vol 132 (2) ◽  
Author(s):  
Lan Ren ◽  
Todd Sparks ◽  
Jianzhong Ruan ◽  
Frank Liou
Keyword(s):  
Process Planning ◽  
Manufacturing Process ◽  
Computer Aided Design ◽  
Manufacturing System ◽  
Deposition Process ◽  
Cnc Machining ◽  
Machining Process ◽  
Hybrid Manufacturing ◽  
Integrated Process ◽  
Planning Framework

A hybrid manufacturing system integrates computer numerical controlled (CNC) machining process and layered deposition process and achieves the benefits of both processes. An integrated process planning framework, which includes every module of the hybrid manufacturing process is critical for making the building of functional parts feasible and reliable. In this paper, the hybrid manufacturing system is introduced and the integrated process planning framework, which aims to automate the hybrid manufacturing is investigated. Critical components of the process planning, including decomposition of the computer-aided design (CAD) model, improvement of the toolpath generation pattern, and collision detection algorithms, are discussed. The interfacing and integrating process between deposition and surface finish machining is also studied. The goal of integrated process planning is to realize the automatic hybrid manufacturing process without much human interference. Experiments are implemented to validate the feasibility and reliability of the integrated process planning framework.

scholarly journals Membrane Distillation for the Production of Pharmaceutical-Grade Water—Investigation into the Application of AGMD and VMD

2021 ◽  
Vol 18 (11) ◽  
pp. 6058
Author(s):  
Cornelius Nellessen ◽  
Thomas Klein ◽  
Hans-Jürgen Rapp ◽  
Frank Rögener
Keyword(s):  
Energy Demand ◽  
Tap Water ◽  
Membrane Distillation ◽  
Pharmaceutical Products ◽  
Optimum Process ◽  
The European Union ◽  
Pharmaceutical Ingredients ◽  
Multi Stage ◽  
One Step ◽  
Selection Of

The production of pharmaceutical ingredients, intermediates and final products strongly depends on the utilization of water. Water is also required for the purification and preparation of reagents. Each specific application determines the respective water quality. In the European Union, the European Pharmacopeia (Ph. Eur.) contains the official standards that assure quality control of pharmaceutical products during their life cycle. According to this, the production of water for pharmaceutical use is mainly based on multi-stage distillation and membrane processes, especially, reverse osmosis. Membrane distillation (MD) could be an alternative process to these classical methods. It offers advantages in terms of energy demand and a compact apparatus design. In the following study, the preparation of pharmaceutical-grade water from tap water in a one-step process using MD is presented. Special emphasis is placed on the performance of two different module designs and on the selection of optimum process parameters.

Effect of Mechanical Alignment System on Assembly Accuracy

2000 ◽  
Author(s):  
Neville K. S. Lee ◽  
Grace H. Yu ◽  
Y. Zou ◽  
J. Y. Chen ◽  
Ajay Joneja
Keyword(s):  
Alignment Accuracy ◽  
Mechanical Alignment ◽  
Mechanical Assembly ◽  
Surface Waviness ◽  
Form Errors ◽  
Multi Stage ◽  
Assembly Accuracy ◽  
Alignment System ◽  
Simulation Based ◽  
Selection Of

Abstract Mechanical means of positioning are frequently used in mechanical assembly processes. However, very little attention has been paid to the selection of mechanical alignment systems (MAS) for assembly processes. Our analysis shows that if the MAS are not properly selected, the form errors as well surface waviness and roughness of the workpieces to be assembled can badly limit the level of accuracy achievable. A simulation-based methodology is described to study the alignment accuracy for multi-stage processes. Such cases are common, where fabrication operations are done on parts before they are assembled. The study shows that if the workpieces are aligned in the same orientation, using similar or identical MAS for the fabrication processes and assembly processes, then the effect of the form errors as well as surface waviness and roughness of the workpieces can be greatly suppressed.

An Interactive Visualization of Genetic Algorithm on 2-D Graph

2012 ◽  
Vol 4 (1) ◽  
pp. 34-54 ◽  
Author(s):  
Humera Farooq ◽  
Nordin Zakaria ◽  
Muhammad Tariq Siddique
Keyword(s):  
Genetic Algorithm ◽  
Growth Process ◽  
Search Space ◽  
Human Intervention ◽  
Branching Structures ◽  
Multidimensional Search ◽  
L System ◽  
User Fatigue ◽  
Search Data ◽  
Selection Of

The visualization of search space makes it easy to understand the behavior of the Genetic Algorithm (GA). The authors propose a novel way for representation of multidimensional search space of the GA using 2-D graph. This is carried out based on the gene values of the current generation, and human intervention is only required after several generations. The main contribution of this research is to propose an approach to visualize the GA search data and improve the searching process of the GA with human’s intention in different generations. Besides the selection of best individual or parents for the next generation, interference of human is required to propose a new individual in the search space. Active human intervention leads to a faster searching, resulting in less user fatigue. The experiments were carried out by evolving the parameters to derive the rules for a Parametric L-System. These rules are then used to model the growth process of branching structures in 3-D space. The experiments were conducted to evaluate the ability of the proposed approach to converge to optimized solution as compared to the Simple Genetic Algorithm (SGA).

An expectation-based account of subject islands and parasitism

2012 ◽  
Vol 49 (2) ◽  
pp. 285-327 ◽  
Author(s):  
RUI P. CHAVES
Keyword(s):  
Full Range ◽  
Search Space ◽  
Functional Explanation ◽  
Parasitic Extraction ◽  
Speed Up

Subject phrases impose particularly strong constraints on extraction. Most research assumes a syntactic account (e.g. Kayne 1983, Chomsky 1986, Rizzi 1990, Lasnik & Saito 1992, Takahashi 1994, Uriagereka 1999), but there are also pragmatic accounts (Erteschik-Shir & Lappin 1979; Van Valin 1986, 1995; Erteschik-Shir 2006, 2007) as well as performance-based approaches (Kluender 2004). In this work I argue that none of these accounts captures the full range of empirical facts, and show that subject and adjunct phrases (phrasal or clausal, finite or otherwise) are by no means impermeable to non-parasitic extraction of nominal, prepositional and adverbial phrases. The present empirical reassessment indicates that the phenomena involving subject and adjunct islands defies the formulation of a general grammatical account. Drawing from insights by Engdahl (1983) and Kluender (2004), I argue that subject island effects have a functional explanation. Independently motivated pragmatic and processing limitations cause subject-internal gaps to be heavily dispreferred, and therefore, extremely infrequent. In turn, this has led to heuristic parsing expectations that preempt subject-internal gaps and therefore speed up processing by pruning the search space of filler–gap dependencies. Such expectations cause processing problems when violated, unless they are dampened by prosodic and pragmatic cues that boost the construction of the correct parse. This account predicts subject islands and their (non-)parasitic exceptions.

Sample selection of prognostics validation test based on multi-stage Wiener process

2018 ◽  
Vol 233 (4) ◽  
pp. 605-614
Author(s):  
Zhiao Zhao ◽  
Yong Zhang ◽  
Guanjun Liu ◽  
Jing Qiu
Keyword(s):  
Wiener Process ◽  
Process Model ◽  
Failure Modes ◽  
Early Stage ◽  
Sample Selection ◽  
Degradation Process ◽  
Time Interval ◽  
Degradation Data ◽  
Multi Stage ◽  
Selection Of

Sample allocation and selection technology is of great significance in the test plan design of prognostics validation. Considering the existing researches, the importance of prognostics samples of different moments is not considered in the degradation process of a single failure. Normally, prognostics samples are generated under the same time interval mechanism. However, a prognostics system may have low prognostics accuracy because of the small quantity of failure degradation and measurement randomness in the early stage of a failure degradation process. Historical degradation data onto equipment failure modes are collected, and the degradation process model based on the multi-stage Wiener process is established. Based on the multi-stage Wiener process model, we choose four parameters to describe different degradation stages in a degradation process. According to four parameters, the sample selection weight of each degradation stage is calculated and the weight of each degradation stage is used to select prognostics samples. Taking a bearing wear fault of a helicopter transmission device as an example, its degradation process is established and sample selection weights are calculated. According to the sample selection weight of each degradation process, we accomplish the prognostics sample selection of the bearing wear fault. The results show that the prognostics sample selection method proposed in this article has good applicability.

scholarly journals KOMPETENSI PETERNAK SAPI POTONG PERANAKAN ONGOLE DALAM PEMBUATAN KOMPOS (STUDI KASUS PADA KELOMPOK TERNAK MEKAR KECAMATAN DAGANGAN KABUPATEN MADIUN)

2018 ◽  
Vol 10 (3) ◽  
pp. 1
Author(s):  
Deha Purwoko ◽  
Bekti Nur Utami
Keyword(s):  
Manufacturing Process ◽  
Research Method ◽  
Organic Content ◽  
Compost Quality ◽  
Preparation Stage ◽  
Before And After ◽  
Descriptive Approach ◽  
Quantitative Descriptive ◽  
Selection Of

This research aims to describe the level of competence of farmers in composting, and to draft extension and try out the implementation of counseling about composting in group of livestock of Mekar. The research was conducted in sub-district Dagangan of Madiun Regency. Selection of livestock group is done by purposive that is the only group of livestock that have made compost that is group of livestock of Mekar which is located in Kepet village. The research method used is case study with quantitative descriptive approach with scoring. The population is 44 people, the sample is based on the census. The results showed that: 1) the level of competence of farmers in composting is classified with the details of the competence of the preparation stage is low, the competence of the manufacturing process is low, and the competence of the storage stage is classified; and 2) drafting the extension plan based on the target and the purpose of extension so that the breeder know, understand and able to increase the C-Organic content and C / N Ratio on the compost according to the standard. Success shows the improvement of compost quality before and after counseling in accordance with the purpose of counseling.   Keywords: competence of breeder, livestock group of Mekar, draft extension, composting, extension

Controlling Penetration Depth in Projection Stereolithography by Adjusting the Operation Wavelength

2014 ◽  
Vol 611-612 ◽  
pp. 756-762 ◽  
Author(s):  
Pekka Lehtinen ◽  
Santeri Laurila ◽  
Matti Kaivola ◽  
Jouni Partanen
Keyword(s):  
Penetration Depth ◽  
Layer Thickness ◽  
Manufacturing Process ◽  
Commercial Resin ◽  
Speed Up ◽  
Curing Light ◽  
Projection Stereolithography

In projection stereolithography, the cure depth and thereby the layer thickness in the manufacturing process may be varied by changing the operation wavelength. The change can be made even in the middle of the manufacturing process, which opens up possibilities for additional flexibility and speed-up of the process.In this paper, we investigate how the penetration depth of the curing light in the resin depends on the wavelength. The measurements were performed for wavelengths between 400 nm and 550 nm using a standard commercial resin. The penetration depth was found to almost double when moving from the short wavelengths to the long ones.

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