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An approach to fixture systems management in machining processes
Consalter, L. A.;Boehs, L.;
Journal of the Brazilian Society of Mechanical Sciences and Engineering , 2004, DOI: 10.1590/S1678-58782004000200005
Abstract: starting from the premise that the management of fixture systems in the area of machining has been somewhat neglected from the standpoint of its technological development, the work reported on herein focuses on the development of a methodology for the management of these systems. based on the findings of a survey carried out at companies operating in this sector and on a review of the literature on the subject, both of which confirm this lack, hypotheses are drawn up and supporting data compiled to underpin the development of a systematic, extensive and flexible model. the model, founded on principles of standardization and modularity, basically consists of four main stages: the company's definition/characterization of fixtures management, selection of the type of fixture suitable for the company, rationalization and organization of the area, and the construction of planning and control architectures within the company. we foresee that the formalization of the scientifically-based management support model proposed here will contribute significantly to productive and r&d sectors, computerizing the fixtures management methods used by companies and integrating their managerial philosophies and procedures for machining tools and fixtures.
Optimization of machining fixture layout for tolerance requirements under the influence of locating errors
S Vishnupriyan, M.C Majumder, K Ramachandran
International Journal of Engineering, Science and Technology , 2010,
Abstract: Dimensional accuracy of workpart under machining is strongly influenced by the layout of the fixturing elements like locators and clamps. Setup or geometrical errors in locators result in overall machining error of the feature under consideration. Therefore it is necessary to ensure that the layout is optimized for the desired machining tolerance for a given deviation in the set up or geometry of the locator. Also, the locator layout should be capable of holding the workpart in a unique position during machining thus providing deterministic location. This paper proposes a Genetic Algorithm (GA) based optimization method to arrive at a layout of error containing locators for minimum machining error satisfying the tolerance requirements and providing deterministic location. A three dimensional workpiece under the 3-2-1 locating scheme is studied. Results indicate that by optimally placing the error containing locators the geometric error component of the machining error can be substantially reduced thus enabling compliance to overall dimensional requirements.
Optimization of machining fixture layout for tolerance requirements under the influence of locating errors  [PDF]
S. Vishnupriyan,M. C. Majumder,K. P. Ramachandran
International Journal of Engineering, Science and Technology , 2010,
Abstract: Dimensional accuracy of workpart under machining is strongly influenced by the layout of the fixturing elements like locators and clamps. Setup or geometrical errors in locators result in overall machining error of the feature under consideration. Therefore it is necessary to ensure that the layout is optimized for the desired machining tolerance for a given deviation in the set up or geometry of the locator. Also, the locator layout should be capable of holding the workpart in a unique position during machining thus providing deterministic location. This paper proposes a Genetic Algorithm (GA) based optimization method to arrive at a layout of error containing locators for minimum machining error satisfying the tolerance requirements and providing deterministic location. A three dimensional workpiece under the 3-2-1 locating scheme is studied. Results indicate that by optimally placing the error containing locators the geometric error component of the machining error can be substantially reduced thus enabling compliance to overall dimensional requirements.
面向电弧放电加工的旋转冲液夹具模态分析及结构优化研究
Modal Analysis and Structural Optimization of Rotary Flushing Fixture for Arc Discharge Machining
 [PDF]

王庆,谢习华,张立斌
- , 2018,
Abstract: 根据电弧放电加工过程利用高速冲液流场对电弧进行有效控制的工作原理,设计了一套用于实现高速内冲液功能的旋转冲液夹具。旋转冲液夹具的动态特性对电弧放电加工的加工性能具有明显影响,因此,采用ANSYS有限元分析软件对冲液夹具进行模态仿真分析。仿真结果表明,冲液夹具在工作时会出现沿某些方向的剧烈振动,导致弹性部件发生较大的变形。分析仿真结果可知,通过改进材料属性和几何模型,可以减小弹性部件的振动变形,最终实现旋转冲液夹具的结构优化。
Based on the theory of arcing controlling with the high-speed inner flushing flow fluid forming while machining, the rotary flushing fixture is designed. Furthermore, the dynamic characteristics of the rotary flushing fixture have the significant effect on the machining performance of the arc discharge machining. Therefore, the modal simulation analysis is conducted to explore the vibrant performance of the flushing fixture by a finite element analysis software ANSYS. The simulation results show that the vibration in some directions of the flushing rotary fixture would occur violently while machining, which results in large elastically deformation parts. The simulation analysis results show that the deformation of the elastic parts could be decreased by adopting the different material properties and geometric model, from which the structure optimization of the rotary flushing fixture could be realized
Study of Computer-Aided Design Process and Methods Based on Welding Fixture  [cached]
Yi Zhang,Sihui Mu
Journal of Computers , 2012, DOI: 10.4304/jcp.7.6.1421-1428
Abstract: Although various computer-aided fixture design (CAFD) systems have been developed to assist the designer during the various stages of fixture design, most of previous computer aided fixture design research has mainly concentrated on machining fixtures rather than welding fixtures. The development of complicated computer aided welding fixture design (CAWFD) system has received much less attention. Welding fixture can ensure welding dimension, improve assembly precision and efficiency. It can prevent the welding deformation. The function of welding fixture was introduced in this paper. The computer-aided welding fixture design workflow was developed. The design steps include the project creation, setup design, Orientation and position determination, fixture plan design, fixture configuration design, fixture design verification and fixture design output. The classification of welding fixture component has been demonstrated. Information tree and the database tables to save the unit information are designed. The unit information retrieval menu and interface based on UG, Visual C++ and database is realized.
Dietary supplement education in a senior population  [PDF]
Kimberly G. Elder, Sarah A. Nisly
Open Journal of Internal Medicine (OJIM) , 2011, DOI: 10.4236/ojim.2011.13015
Abstract: Background: Dietary supplements are widely used among United States senior citizens for various indications. Potential dangers with supplement use include the lack of regulation by the Food and Drug Administration (FDA) and the possibility for drug-supplement interactions. Senior focused education may increase the safe use of dietary supplements by older adults. Objective: The primary objective of this study was to determine the effectiveness of a pharmacist driven educational seminar in a local senior population. Methods: Participants aged 55 years and older in one of three senior programs were eligible for inclusion. Initially, a needs-assessment interview was conducted at a health fair. At that time, interviews focusing on dietary supplement use were delivered to study participants. Following the health fair, interview responses were analyzed to determine the most commonly used dietary supplements. During the second phase of the project, an educational seminar focusing on general dietary supplement information and the most commonly used supplements in the phase one population was created and delivered. Pre- and post-surveys were administered at the seminar to gauge baseline knowledge and impact of pharmacist education. Additionally, results were analyzed for any change in attitudes about dietary supplements. Results: Forty-nine participants were interviewed about their use of dietary supplements at the initial health fair. Among these participants, 81.6% were taking at least one supplement. The most commonly used supplements were calcium (n = 23), multivitamins (n = 22), fish oil (n = 13), and vitamin B (n = 12). Approximately 180 participants attended the subsequent educational seminar. Knowledge statistically significantly improved from baseline for all six questions posed to study participants. Overall, the program was well received and attitudes about dietary supplements changed as a result of viewing the seminar. Conclusions: Dietary supplements were commonly used by the study population for various indications. Education by pharmacists is an effective method to increase knowledge and awareness about dietary supplements among this population.
An Interactive Web-based Learning System for Assisting Machining Technology Education  [cached]
Chi-Chia Liu,Min Jou
International Journal of Online Engineering (iJOE) , 2008, DOI: 10.3991/ijoe.v4i2.484
Abstract: The key technique of manufacturing methods is machining. The degree of technique of machining directly affects the quality of the product. Therefore, the machining technique is of primary importance in promoting student practice ability during the training process. Currently, practical training is applied in shop floor to discipline student’s practice ability. Much time and cost are used to teach these techniques. Particularly, computerized machines are continuously increasing in use. The development of educating engineers on computerized machines becomes much more difficult than with traditional machines. This is because of the limitation of the extremely expensive cost of teaching. The quality and quantity of teaching cannot always be promoted in this respect. The traditional teaching methods can not respond well to the needs of the future. Therefore, this research aims to the following topics; (1).Propose the teaching strategies for the students to learning machining processing planning through web-based learning system. (2).Establish on-line teaching material for the computer-aided manufacturing courses including CNC coding method, CNC simulation. (3).Develop the virtual machining laboratory to bring the machining practical training to web-based learning system. (4).Integrate multi-media and virtual laboratory in the developed e-learning web-based system to enhance the effectiveness of machining education through web-based system.
Diploma Supplement - Instrument of the Quality Assurance Process in the Romanian Higher Education?  [cached]
M?d?lina Coco?atu
EIRP Proceedings , 2012,
Abstract: The quality of education, graduate’s performances and the level of abilities and skills acquiredduring their studies are reflected in the Diploma Supplement, crucial tool in ensuring quality in highereducation and in university’s activity centering on the student. The Diploma Supplement is a response tochallenges, aiding mobility and access to lifelong learning opportunities. It promotes transparency in highereducation and fair and informed judgements about qualifications. National higher education institutionsproduce the supplement according to a template jointly developed by the European Commission, the Councilof Europe and UNESCO. The purposes of this paper are to analyze the importance of universities’classification realized for the first time in Romania and the impact that it has on student, because I considerthat the student is very important for developing universities’ structure and activities.
ALGORITMA PENENTUAN TITIK PENCEKAMAN HOLE-BASED MODULAR FIXTURE  [cached]
Josef Hernawan Nudu,Isa Setiasyah Toh
Jurnal Teknik Industri , 2008,
Abstract: This article illustrates fixturing algorithm for determining clamping point of hole-based modular fixture. The proposed algorithm is based on the algorithm developed by Ariastuti et al. The previous algorithm could be applied for determining clamping point of dedicated or slot-based modular fixture but it can not be applied directly for hole-based modular fixture. Conversion of locators’ coordinate and clamping coordinate into coincident baseplate-coordinates and an approach for modeling the magnitude and action point of equivalent forces are proposed. This algorithm is designed for fixturing prismatic workpart having machining feature(s) being processed on a vertical milling machine. The machining features are hole, blind hole, pocket, slot, blind slot, step, and blind step. Three hypothetical worksamples were analyzed using Ariastuti’s algorithm and this new algorithm. The result shows that both algorithms have the same properties in terms of feasible fixturing and unfeasible fixturing on a single setup.The new algorithm gives coordinates that coincide with holes of related baseplate in feasible fixturing. Forces equilibrium during machining is the only aspect being considered for feasibity analysis. Fixture elements’ dimension, strength, and deformation have not been considered yet. Abstract in Bahasa Indonesia: Makalah ini memaparkan algoritma fixturing untuk penentuan titik pencekaman fixture modular jenis hole yang dikembangan dari algoritma Ariastuti et al. Algoritma Ariastuti et al. dapat digunakan untuk menentukan titik pencekaman dedicated fixture dan modular fixture jenis slot, namun tidak dapat diterapkan secara langsung pada modular fixture jenis hole. Algoritma usulan menambahkan satu tahapan berupa penyesuaian koordinat lokator dan klem yang bersesuaian dengan posisi lubang pada plat dasar modular fixture jenis hole. Algoritma yang diusulkan berbeda dalam hal penentuan besar dan titik tangkap gaya potong ekivalen, serta penentuan titik pencekaman yang dipilih. Penelitian dibatasi pada fixturing benda kerja prismatik yang memiliki feature hole, blind hole, pocket, slot, blind slot, step, dan blind step untuk pemesinan pada mesin milling vertikal. Fisibilitas fixturing ditentukan oleh kondisi kesetimbangan gaya selama proses pemesinan. Aplikasi algoritma usulan pada tiga buah benda uji hipotetis memberikan hasil yang setara dengan algoritma Ariastuti et al.; berupa kondisi fixturing fisibel atau tidak fisibel. Hasil kondisi fixturing yang fisibel adalah titik lokator dan klem yang bersesuaian dengan posisi susunan lubang pada plat dasar fix
Effect of education on the knowledge and applying folic acid supplement in women at reproductive ages
Mirmohammadali M,Moddares M,Babaei Gh,Kamravamanesh M
Hayat Journal of Faculty of Nursing & Midwifery , 2004,
Abstract: Introduction: Folic acid is one of the most important vitamins for women of reproductive ages, especially before conception and during pregnancy. Many researches have shown the role of folic acid in prevention of fetal malformations especially neural tube defects, anemia, cardiovascular disease and some cancers. Material and Methods: This research is a semi-experimental study. A sample of 130 married women at reproductive ages (15-45 year) referring to health centers in Kermanshah was selected randomly. The tool for collecting data was questionnaire. After filling the pretest questionnaire, each woman participated in a face to face 15 minutes educational session. Two weeks later the same questionnaire was filled by the participant. To analyze the data, the descriptive statistics, frequency distribution charts, the mean and central tendency as well as validating statistics ( 2 test and t test) was used. Results: The results indicated that there was a statistically significant difference in amount of knowledge (p 0.0001, t=-27.381) and the amount of usage (p=0.0001, 2 = 42.968) of folic acid supplement before and after education. This difference was more prominent in women between 25-29 years of age, self-employed, with diploma degree, housewives, having diploma holding husbands and first time pregnancies. Conclusion: The amount of information and usage of folic acid supplement increased significantly after education. This finding reveals the importance of health education and the important role of health personnel such as midwives. Therefore, it is suggested that women of reproductive ages be informed of importance of taking folic acid supplement.
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