Journal articles: 'One-Piece-Flow'

1

Nyhuis, Peter, and Markus Vogel. "Logistische Positionierung von One-Piece-Flow-Prozessen." ZWF Zeitschrift für wirtschaftlichen Fabrikbetrieb 100, no. 3 (March 27, 2005): 99–103. http://dx.doi.org/10.3139/104.100869.

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Hu, Luo Yan, Ya Rui Huo, Chang Qing Jin, Yan Zheng, Qian Zheng, and Yan Yan Xu. "One-Piece Flow Implementation Research in the Garment Enterprises." Advanced Materials Research 655-657 (January 2013): 2352–57. http://dx.doi.org/10.4028/www.scientific.net/amr.655-657.2352.

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One-piece flow is one of the effective tools of lean production. Many garment enterprises expect to implement it in their own enterprises, but a lot of difficulties exist in the implementation process. In this paper, it takes an example of a well-known processing enterprise and to study the one-piece flow implementation process of a pair of jeans pipeline. By nearly a year of tracking and research, the paper systematically summarizes the pre-production preparation and production maintenance in the implementation of the One-piece flow. It demonstrates in detail on how to achieve the improvement of the hardware, software and personnel in order to reach the requirement of one-piece flow. Then, it systematically discusses the wage system of one-piece flow and will provide a theoretical and practical basis for the implementation of a single-piece flow production.

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Nyhuis, Peter, and Markus Vogel. "Adaptation of logistic operating curves to one‐piece flow processes." International Journal of Productivity and Performance Management 55, no. 3/4 (April 1, 2006): 284–99. http://dx.doi.org/10.1108/17410400610653237.

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PurposeTo provide a model for precise logistic controlling of one‐piece flow processes and for the description of the interactions between logistic performance measures. The developed method can help manufacturing enterprises to control their production processes and therewith to exploit existing rationalization potentials in their production.Design/methodology/approachThe Institute of Production System and Logistics adapted the logistic operating curve for schedule reliability and the logistic operating curve for mean throughput time to describe the behaviour of one‐piece flow processes. This model‐based method depicts the correlation between the delivery reliability and mean WIP level of single manufacturing systems and enables a goal‐oriented modelling as well as a controlling of single manufacturing processes.FindingsThe derivation, calculation, and fields of application of the logistic operating curves for one‐piece flow processes, that give a functional relationship between mean WIP, mean throughput time and schedule reliability, are presented in this paper. Moreover, the paper presents how the logistic performance measures can be adjusted to target values.Originality/valueThis paper offers practical help to manufacturing enterprises confronted with the task of evaluation and optimization of manufacturing processes within the framework of production controlling. Moreover, the developed method enables manufacturing enterprises to identify bottleneck work systems where action can be taken to optimize their schedule situation and thereby improve the delivery reliability of an entire manufacturing department.

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MILTENBURG, JOHN. "One-piece flow manufacturing on U-shaped production lines: a tutorial." IIE Transactions 33, no. 4 (April 2001): 303–21. http://dx.doi.org/10.1080/07408170108936831.

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INOUE, Reiko, and Youichi NONAKA. "Development of Transportation Control System for Buffer-less One-Piece Flow Line." Journal of the Japan Society for Precision Engineering 80, no. 3 (2014): 322–27. http://dx.doi.org/10.2493/jjspe.80.322.

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Shi, ZhuanZhuan, YunLi Tian, XiaoShuai Wu, ChangMing Li, and Ling Yu. "A one-piece lateral flow impedimetric test strip for label-free clenbuterol detection." Analytical Methods 7, no. 12 (2015): 4957–64. http://dx.doi.org/10.1039/c5ay00706b.

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Ioana, Apafaian Dumitrita, Egri Diana Maria, and Veres Cristina. "Case Study Regarding the Implementation of One-Piece Flow Line in Automotive Company." Procedia Manufacturing 46 (2020): 244–48. http://dx.doi.org/10.1016/j.promfg.2020.03.036.

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Kneer, Aron, Michael Wirtz, Marcel Can Bozkurt, Alexander Solohub, Timo Laufer, Markus Hauf, Thomas Altmannsberger, Hermann Bieg, and Stephan Barbe. "One‐Piece Stainless‐Steel 3D Printed Minichannel Evaporators using Flow Boiling Carbon Dioxide." Chemical Engineering & Technology 43, no. 5 (March 3, 2020): 923–32. http://dx.doi.org/10.1002/ceat.202000069.

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Li, S. G., Y. Ni, X. Wang, L. Shi, and L. J. Zhu. "Design of one-piece flow production system with mixed flows: a timed process flow diagram-based approach." International Journal of Computer Integrated Manufacturing 25, no. 11 (November 2012): 996–1010. http://dx.doi.org/10.1080/0951192x.2012.684709.

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Li, S. G., and Y. L. Rong. "The reliable design of one-piece flow production system using fuzzy ant colony optimization." Computers & Operations Research 36, no. 5 (May 2009): 1656–63. http://dx.doi.org/10.1016/j.cor.2008.03.010.

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Liu, Chuntong, Zhengyi Zhang, Hongcai Li, Zhenxin He, Xiaofeng Zhao, and Rongjing Wu. "Research on one-piece structure target flow sensing technology based on fiber Bragg grating." Photonic Sensors 6, no. 4 (October 13, 2016): 303–11. http://dx.doi.org/10.1007/s13320-016-0352-6.

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William, A., and P. E. Miller. "Review of:“One-Piece Flow — Cell Design for Transforming”, Kenichi Sekine, Productivity Press, Cambridge, MA, Year: 1992." IIE Transactions 24, no. 4 (September 1992): 111. http://dx.doi.org/10.1080/07408179208964238.

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SUEMATSU, Kota, Hiroyuki KOUSAKA, and Tatsuya FURUKI. "Development of HiPIMS deposition technology using a cylindrical target surrounding a substrate for one-piece-flow coating." Proceedings of Mechanical Engineering Congress, Japan 2020 (2020): S11507. http://dx.doi.org/10.1299/jsmemecj.2020.s11507.

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Scholz, Michael, Saskia Kolb, Christopher Kästle, and Jörg Franke. "Operation-oriented One-piece-flow Manufacturing: Autonomous and Smart Systems as Enabler for a Full-meshed Production Network." Procedia CIRP 57 (2016): 722–27. http://dx.doi.org/10.1016/j.procir.2016.11.125.

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Naufal, Ahmad Adnan, Ahmed Jaffar, Yusoff Noriah, and Nurul Hayati Abdul Halim. "Implementation of Continuous Flow System in Manufacturing Operation." Applied Mechanics and Materials 393 (September 2013): 9–14. http://dx.doi.org/10.4028/www.scientific.net/amm.393.9.

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The Continuous Flow System (CFS) is a production system that focuses on one piece flow product at every process in the assembly line. The implementation of this CFS could lead to operational excellence in terms of productivity, space utilization and the number of workers. CFS can be considered as a lean manufacturing foundation and its effective implementation promises significant savings in operation. CFS is achieved through a series of associated kaizen activities at the identified working place. The kaizen activities include establishment of Standardized Work (SW), implementation of U-shaped line and establishment of Material Handling System (MHS). All these activities are carried with one ultimate goal; to eliminate identified waste at the work place. This is essential to any CFS implementation. This paper presents a series of kaizen activities that have been engaged in creating the continuous flow system at the identified assembly line. This is a case-based study which was conducted at a local auto-component company in Malaysia. Findings from the results show that the company has achieved high productivity, minimal space utilization as well as reduction in number of direct manpower. The outcome of this CFS implementation confirms that it has met the supposedly lean principles also known as the one piece flow. Therefore, the objective of this study is to highlight the implemented kaizen activities and its benefit in achieving the CFS of the case study.

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Satoglu, Sule Itir, Mehmet Bulent Durmusoglu, and Tijen Ertay. "A mathematical model and a heuristic approach for design of the hybrid manufacturing systems to facilitate one-piece flow." International Journal of Production Research 48, no. 17 (August 13, 2009): 5195–220. http://dx.doi.org/10.1080/00207540903089544.

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Cheng, Mei, and Zhi Min Zhang. "Metal Flow Behaviour in Tee Joint Valve Body Multidirectional Extrusion." Materials Science Forum 747-748 (February 2013): 431–36. http://dx.doi.org/10.4028/www.scientific.net/msf.747-748.431.

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By multi-axis active load deformation method, the equivalence diameter tee joint was formed on multi-axis numerical control hydraulic press machine. The loading route was determined by numerical simulation. The experiment results showed that two loading method can complete form the parts. The different directions metal flow was observed under multi-axis loading conditions. To simplify analysis, the flow field was divided into several regions. In every region, the metal flow direction was only one. In multi-axis loading, the way of deformation follows priority deformation principle: The metal flows only choose one direction even if the work piece were under the complicated coupling field condition. The mathematical model of the deformation force and metal flow rate was established. The theoretical calculation had been provided.

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Misirli, Cenk. "On materials flow using different lubricants in upsetting process." Industrial Lubrication and Tribology 66, no. 5 (August 5, 2014): 623–31. http://dx.doi.org/10.1108/ilt-01-2012-0009.

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Purpose – The purpose of this paper is to apply the upsetting process to cylindrical specimens using flat end dies in which three types of lubricants were used. In many industrial processes, friction and lubrication have major advantages and are key during the metal forming process. Upset forging is a process which increases the diameter of the work-piece by compressing its length. Design/methodology/approach – The materials flow for various materials using different lubricants in upsetting was investigated in this study. AISI 304 austenitic-stainless steel and commercially pure aluminium (Al99.7) were used as the test materials. The upsetting process was applied to the cylindrical specimens using flat end dies. Three types of lubricants, namely, grease, graphite and SAE 40 oil, were used in this study. Experiments were performed using a hydraulic press, which has 5 mm/s ram speed, with a capacity of 150 metric tons. On the other hand, finite element methods (FEMs) have been carried out to analyse the forming performance for displacement prediction in the barrelling process. Findings – The results showed that the measured radius of the curvature of the barrel seemed to confirm the calculation values used before the initiation of the experimental process. It has been observed that the surface roughness had no considerable effect on the barrelling contour changes on the free surfaces, as it showed an increasing deformation ratio for all materials and lubricant types. However, minimum friction at the interface seems to occur with the grease lubricant. The present analyses show that FEMs, which can be used in the rapid prediction of required barrelling process displacements, are more suitable for use in a pressure distribution analysis for the development of the barrelling radius. Research limitations/implications – It would be interesting to search the material flow for more different materials and lubricants. It could be a good idea if future work could be concentrated on the material flow on upsetting by using different lubricants. Practical implications – Open-die forging, which is also known as the upsetting process, is one of the simplest forging operations used in bulk deformation processes. This operation can be explained as a solid work-piece which is positioned between two flat dies, and then with the aid of compression, the height of the work-piece is reduced under controlled working parameters during the upsetting process, in which friction and surface roughness are the major parameters playing an important role on the material flow. In a cold upsetting process, one of the undesirable conditions is that barrelling occurs as a consequence of friction between the work-piece and the die surfaces. The existence of this frictional constraint directly affects the plastic deformation of the work-piece, as friction causes barrelling in upsetting processes. However, it has been observed that the use of lubricants reduces the degree of bulging. Social implications – This paper will be useful for industrial applications. Originality/value – The main value of this paper is to contribute and fulfil in detail the material flow of various materials using different lubricants that are being studied so far in the literature.

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Beachum, Dan. "Lean manufacturing beefs up marginspull systems, takt time, and one-piece flow benefit the operation of a powder coating system." Metal Finishing 103, no. 1 (January 2005): 20–25. http://dx.doi.org/10.1016/s0026-0576(05)80010-8.

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Skołud, Bożena, Damian Krenczyk, and Marcin Zemczak. "An Idea of the Continuous Flow for Concurrent Multi-Assortment Production." Applied Mechanics and Materials 809-810 (November 2015): 1444–49. http://dx.doi.org/10.4028/www.scientific.net/amm.809-810.1444.

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Nowadays in the era of advanced stage of Lean Manufacturing concept forces manufacturers to research of new idea of the production flow organization and to implement more and more innovative organizational solutions. The article presents the authors concept of implementation the combination of continuous flow and concurrent multi assortment production. Continuous flow is an approach to discrete manufacturing that contrast with batch production and is associated with just-in-time and Kanban production. The goal is an optimal balanced line. The paradigm aim is to achieve single-piece flow. For this purpose the similarity of the products that use the shared resources and start their production one by one in a predetermined sequence is searched. In addition, it is recommended to transform the internal setup into external one for eliminating investment in set-up times. This concept is similar to the group technology developed down in 70’s and based on the classification of products into four groups.

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Andersen, Hanne Voldborg, and Elsebeth Korsgaard Sorensen. "Enhancing Understanding, Flow And Self-Efficacy In Learners With Developmental And Attention Difficulties Through ICT-Based Interventions." European Journal of Open, Distance and E-Learning 20, no. 1 (June 27, 2017): 154–75. http://dx.doi.org/10.1515/eurodl-2017-0010.

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AbstractThe purpose of this paper is to investigate in which ways technologies may be used to increase inclusion and a feeling of flow and self-efficacy in learning processes when it comes to learners with developmental and attention deficits (focus learners) in a mainstream classroom. The paper is one piece of outcome of a wider study on ICT facilitated inclusion, and this current piece of research addresses the challenges of enhancing focus learners’ comprehension when working with the curriculum. Several technologies have been tried out in a real school context and seven types of interventions are identified as valuable for focus learners’ capability in learning processes. The paper discusses the findings and concludes that conscious use of technology-based interventions makes it possible to provide learning challenges balanced to the learners’ individual skills. But a broader understanding and acceptance by all stakeholders of the specific challenges of this group of learners in mainstream educational systems seems needed to fulfil the potential.

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Santoso, Gemma Eka, Gita Ayu, and Nike Septivani. "Lean Strategy Implementation to Improve Throughput in Assembly Line: Dul-Db21ssc Manufacturing Process at PT. X." ComTech: Computer, Mathematics and Engineering Applications 4, no. 1 (June 30, 2013): 371. http://dx.doi.org/10.21512/comtech.v4i1.2749.

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Lean production has dramatically lifted the competitiveness of many manufacturing companies and the value they deliver to customers. This project examines the benefit of balancing process and workstation arrangement of dogbone damper in an order that maintains a smooth flow of materials and component through the process. The analysis begins from calculating takt value to establish the required rate of production. From here, any total cycle time exceeding takt time is called a bottleneck process and should become a target of the improvement. Next, arranging people and equipment into cells has great advantage in terms of achieving lean goals. One advantage of cells is the one-piece flow concept, which states that each product moves through the process one unit a time without sudden interruption, at a pace determined by the customer’s need.

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Baldwin, R. M., and H. R. Simmons. "Flow-Induced Vibration in Safety Relief Valves." Journal of Pressure Vessel Technology 108, no. 3 (August 1, 1986): 267–72. http://dx.doi.org/10.1115/1.3264785.

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Flow-induced vibration in safety relief valves (SRV’s) in high-energy piping systems such as power plants is identified as the source of many SRV failures. The mechanism is an unstable coupling of vortex shedding at the mouth of the valve with the side branch acoustic resonance. Characteristics of the problem and computerized methods of acquiring data lead to positive identification of flow-induced vibration. Pulsation and vibration data recorded from several valves in power plant steam service are presented for comparison of stable and unstable configurations. Based on this data, a rational design procedure utilizing the relationship among Strouhal number, Mach number, and stub dimensions has been developed to eliminate an existing problem or to prevent one in a new piping system. Proper side branch sizing coupled with flow stabilization techniques provide for the design of a main pipe to safety valve transition piece which has been shown to be successful in several applications.

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Kozeruk, A. S., Y. L. Malpica, M. I. Filonova, V. I. Shamkalovich, and R. O. Dias Gonzalez. "MATHEMATICAL MODELING OF OPERATIONAL ZONE FOR TECHNOLOGICAL EQUIPMENT USED FOR DOUBLE-SIDED PROCESSING OF LENSES." Science & Technique 17, no. 3 (May 31, 2018): 204–10. http://dx.doi.org/10.21122/2227-1031-2018-17-3-204-210.

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A mathematical modeling of geometric and kinematic relations has been made in respect of an operational zone for one of the standard machine tool sections which is used for simultaneous double-sided abrasive processing of highly-accurate lenses with a small rigidity (with a thin centre) under free lapping conditions. An analytical expression has been obtained for calculation of a sliding velocity in an arbitrarily selected point either on a surface to be processed or on a processing surface. As the proposed technology for simultaneous double-sided processing presupposes oscillatory motion of only processing tools then in order to eliminate a joint opening (a local contact fault between lapping surfaces of a tool and a work-piece) length of a drive piece must be not less than a specified value. In this case a convex tool is rigidly connected with a drive piece and it makes a reversing rotary motion (an oscillatory motion) around a centre of the processed spherical surface and a hinged joint of the centre with an output element of the technological equipment actuation mechanism is realized by transition of the drive piece ball end with a spherical seat in the output unit. In order to reveal analytical dependence of tool drive piece length on radius value of the processed spherical lens surface and friction coefficient in the contact zone of the tool and a work-piece the paper has considered a flow pattern of force while processing concave surfaces of lenses having small radius of curvature in case when the tool is positioned at the top. The friction coefficient included in the obtained expression has been determined for grinding while using suspensions of М40, М28, М10 micro-powders in a cast-iron grinding instrument and polishing while using polyrhythm suspension in a pitch and urethane-foam polisher. A method of the inclined plane has been used in this case and following the method a work-piece of optical glass has been initially lapped to the tool with the help of the appropriate abrasive suspension and the required angle has been determined at the moment when the work-piece started its sliding movement along the tool surface.

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Glenny, R. W., L. Polissar, and H. T. Robertson. "Relative contribution of gravity to pulmonary perfusion heterogeneity." Journal of Applied Physiology 71, no. 6 (December 1, 1991): 2449–52. http://dx.doi.org/10.1152/jappl.1991.71.6.2449.

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We designed a series of experiments and analyses to quantify the contribution of gravity to pulmonary perfusion heterogeneity. Regional pulmonary perfusion was measured in five anesthetized and ventilated dogs in both supine and prone positions by use of radiolabeled microspheres injected during apnea at functional residual capacity. Measurements of flow were repeated in each position, and the sequence of positions was prospectively designed to nullify any effect of order. The lungs of each animal were excised, perfused with saline until clear, dried at an inflation pressure of 25 cmH2O, and cut into 1.9-cm3 pieces. Each piece was weighed and the radioactivity determined in a scintillation counter. Measurement errors were minimized by excluding lung pieces that had greater than 25% airway and weighed less than 10 mg or greater than 60 mg. Weight-normalized flows in each position and repetition were determined for each lung piece. An analysis of variance model was used to identify the percentage of variation in regional flow that was due to position (supine vs. prone), to random error and time (measurement and repetition), and to structure, where structure was defined as the component of flow that remained constant across position and replication. The contributions of position, error/time, and structure to the total variability of flow across the five dogs were 7.8 +/- 0.6, 8.4 +/- 8.3, and 83.8 +/- 8.4%, (SD), respectively. Because the contribution of position represents the additive effect of gravity between two opposite positions, the contribution of gravity to perfusion heterogeneity in one position may be as little as 4%.(ABSTRACT TRUNCATED AT 250 WORDS)

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Hedra, Abrahem M. M., Heng Zhi Cai, Ling Xue, Zhen Feng Hao, Xin Liang Wang, and Ya Jun Zhang. "The Design and Analysis of Polymer Cosmetic Micro-Needle." Advanced Materials Research 562-564 (August 2012): 451–54. http://dx.doi.org/10.4028/www.scientific.net/amr.562-564.451.

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At present, most of cosmetic micro-needle in the market is made of biomedical stainless steels, but the processing technology is complicated and the piece-production cost is high. Micro injection molding technology can make the complicated polymer micro-needle in one cycle with the help of the rich experience accumulated in this area. And the method is suitable for mass production. This paper introduces the design of a new type of cosmetic micro-needle with polymer, its number simulation with injection molding software mold flow and the strength simulation.

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Scholle, Markus, Philip H. Gaskell, and Florian Marner. "A Potential Field Description for Gravity-Driven Film Flow over Piece-Wise Planar Topography." Fluids 4, no. 2 (May 2, 2019): 82. http://dx.doi.org/10.3390/fluids4020082.

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Models based on a potential field description and corresponding first integral formulation, embodying a reduction of the associated dynamic boundary condition at a free surface to one of a standard Dirichlet-Neumann type, are used to explore the problem of continuous gravity-driven film flow down an inclined piece-wise planar substrate in the absence of inertia. Numerical solutions of the first integral equations are compared with analytical ones from a linearised form of a reduced equation set resulting from application of the long-wave approximation. The results obtained are shown to: (i) be in very close agreement with existing, comparable experimental data and complementary numerical predictions for isolated step-like topography available in the open literature; (ii) exhibit the same qualitative behaviour for a range of Capillary numbers and step heights/depths, becoming quantitively similar when both are small. A novel outcome of the formulation adopted is identification of an analytic criteria enabling a simple classification procedure for specifying the characteristic nature of the free surface disturbance formed; leading subsequently to the generation of a related, practically relevant, characteristic parameter map in terms of the substrate inclination angle and the Capillary number of the associated flow.

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BARBOT, THIERRY, and SÉRGIO R. FENLEY. "Classification and rigidity of totally periodic pseudo-Anosov flows in graph manifolds." Ergodic Theory and Dynamical Systems 35, no. 6 (July 3, 2014): 1681–722. http://dx.doi.org/10.1017/etds.2014.9.

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In this article we analyze totally periodic pseudo-Anosov flows in graph 3-manifolds. This means that in each Seifert fibered piece of the torus decomposition, the free homotopy class of regular fibers has a finite power which is also a finite power of the free homotopy class of a closed orbit of the flow. We show that each such flow is topologically equivalent to one of the model pseudo-Anosov flows which we previously constructed in Barbot and Fenley (Pseudo-Anosov flows in toroidal manifolds.Geom. Topol. 17(2013), 1877–1954). A model pseudo-Anosov flow is obtained by glueing standard neighborhoods of Birkhoff annuli and perhaps doing Dehn surgery on certain orbits. We also show that two model flows on the same graph manifold are isotopically equivalent (i.e. there is a isotopy of$M$mapping the oriented orbits of the first flow to the oriented orbits of the second flow) if and only if they have the same topological and dynamical data in the collection of standard neighborhoods of the Birkhoff annuli.

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Fahimi, F., and A. H. El-Shafie. "Comment on "A hybrid model of self organizing maps and least square support vector machine for river flow forecasting" by Ismail et al. (2012)." Hydrology and Earth System Sciences 18, no. 7 (July 29, 2014): 2711–14. http://dx.doi.org/10.5194/hess-18-2711-2014.

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Abstract. Without a doubt, river flow forecasting is one of the most important issues in water engineering field. There are lots of forecasting techniques that have successfully been utilized by previously conducted studies in water resource management and water engineering. The study of Ismail et al. (2012), which was published in the journal Hydrology and Earth System Sciences in 2012, was a valuable piece of research that investigated the combination of two effective methods (self-organizing map and least squares support vector machine) for river flow forecasting. The goal was to make a comparison between the performances of self organizing map and least square support vector machine (SOM-LSSVM), autoregressive integrated moving average (ARIMA), artificial neural network (ANN) and least squares support vector machine (LSSVM) models for river flow prediction. This comment attempts to focus on some parts of the original paper that need more discussion. The emphasis here is to provide more information about the accuracy of the observed river flow data and the optimum map size for SOM mode as well.

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Menapace, Rupert. "Mini- and Micro-incision Cataract Surgery – A Critical Review of Current Technologies." European Ophthalmic Review 03, no. 02 (2009): 52. http://dx.doi.org/10.17925/eor.2009.03.02.52.

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Modern cataract surgery is striving for smaller and smaller incisions with the aim of making clear corneal incisions that are as safe and topographically stable as possible. Recent innovations in both phacoemulsification (phaco) and intraocular lens (IOL) technology have made micro-incision cataract surgery, defined as <2mm incision, safe and effective. Bi-axial sleeveless micro-phaco has recently been joined by sleeve-armed micro-co-axial micro-phaco, made possible by the development of slim-shaft strong-bevel phaco needles armed with micro-sleeves that run flush with an enlarged needle head. Such tip technology allows for a highly efficient and safe high-flow, high-vacuum phaco through incisions as small as 1.4mm by providing high influx and suppressing surge while avoiding mechanical and thermal tissue damage. Two tips have so far been made available for mini- (2.2–2.4mm) and micro-incision cataract surgery (MICS) (1.4–1.6mm, depending on the incision architecture used). With the micro-tip supplemented by additional flow through an infusion spatula (‘infusion-assisted’ or ‘hybrid’ phaco), excessive flow and vacuum rates may be used, resulting in a two-fold efficiency as mirrored by the reduced phaco power required. IOL technology is lagging behind phaco technology. The challenge is to avoid trade-offs with regard to implant stability and aftercataract formation, as well as optical performance. Current MICS-IOLs are mostly hydrophilic acrylic one-piece constructions with insufficiently sharp posterior optic edges and broad haptic–optic junctions, both of which features compromise the optic-edge barrier effect. Recently, a hydrophobic three-piece IOL has been made available, which features a slim haptic junction and an exquisitely sharp optic edge and also allows for optional optic entrapment into a posterior capsulorhexis for lasting eradication of after-cataracts.

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Imanaka, Hideaki, Dean Hess, Max Kirmse, Luca M. Bigatello, Robert M. Kacmarek, Wolfgang Steudel, and William E. Hurford. "Inaccuracies of Nitric Oxide Delivery Systems during Adult Mechanical Ventilation." Anesthesiology 86, no. 3 (March 1, 1997): 676–88. http://dx.doi.org/10.1097/00000542-199703000-00021.

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Background Various systems to administer inhaled nitric oxide (NO) have been used in patients and experimental animals. We used a lung model to evaluate five NO delivery systems during mechanical ventilation with various ventilatory patterns. Methods An adult mechanical ventilator was attached to a test lung configured to separate inspired and expired gases. Four injection systems were evaluated with NO injected either into the inspiratory circuit 90 cm proximal to the Y piece or directly at the Y piece and delivered either continuously or only during the inspiratory phase. Alternatively, NO was mixed with air using a blender and delivered to the high-pressure air inlet of the ventilator. Nitric oxide concentration was measured from the inspiratory limb of the ventilator circuit and the tracheal level using rapid- and slow-response chemiluminescence analyzers. The ventilator was set for constant-flow volume control ventilation, pressure control ventilation, pressure support ventilation, or synchronized intermittent mandatory ventilation. Tidal volumes of 0.5 l and 1 l were evaluated with inspiratory times of 1 s and 2 s. Results The system that premixed NO proximal to the ventilator was the only one that maintained constant NO delivery regardless of ventilatory pattern. The other systems delivered variable NO concentration during pressure control ventilation and spontaneous breathing modes. Systems that injected a continuous flow of NO delivered peak NO concentrations greater than the calculated dose. These variations were not apparent when a slow-response chemiluminescence analyzer was used. Conclusions NO delivery systems that inject NO at a constant rate, either continuously or during inspiration only, into the inspiratory limb of the ventilator circuit produce highly variable and unpredictable NO delivery when inspiratory flow is not constant. Such systems may deliver a very high NO concentration to the lungs, which is not accurately reflected by measurements performed with slow-response analyzers.

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Piggush, J. D., and T. W. Simon. "Heat Transfer Measurements in a First-Stage Nozzle Cascade Having Endwall Contouring: Misalignment and Leakage Studies." Journal of Turbomachinery 129, no. 4 (August 11, 2006): 782–90. http://dx.doi.org/10.1115/1.2720506.

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This work supports new gas turbine designs for improved performance by evaluating endwall heat transfer rates in a cascade that is representative of a first-stage stator passage and incorporates endwall assembly features and leakage. Assembly features, such as gaps in the endwall and misalignment of those gaps, disrupt the endwall boundary layer, typically leading to enhanced heat transfer rates. Leakage flows through such gaps within the passage can also affect endwall boundary layers and may induce additional secondary flows and vortex structures in the passage near the endwall. The present paper documents leakage flow and misalignment effects on the endwall heat transfer coefficients within a passage which has one axially contoured and one straight endwall. In particular, features associated with the combustor-to-turbine transition piece and the assembly joint on the vane platform are addressed.

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Cenek, Martin, Rowan Bulkow, Eric Pak, Levi Oyster, Boyd Ching, and Ashika Mulagada. "Semantic Network Analysis Pipeline—Interactive Text Mining Framework for Exploration of Semantic Flows in Large Corpus of Text." Applied Sciences 9, no. 24 (December 5, 2019): 5302. http://dx.doi.org/10.3390/app9245302.

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Historical topic modeling and semantic concepts exploration in a large corpus of unstructured text remains a hard, opened problem. Despite advancements in natural languages processing tools, statistical linguistics models, graph theory and visualization, there is no framework that combines these piece-wise tools under one roof. We designed and constructed a Semantic Network Analysis Pipeline (SNAP) that is available as an open-source web-service that implements work-flow needed by a data scientist to explore historical semantic concepts in a text corpus. We define a graph theoretic notion of a semantic concept as a flow of closely related tokens through the corpus of text. The modular work-flow pipeline processes text using natural language processing tools, statistical content narrowing, creates semantic networks from lexical token chaining, performs social network analysis of token networks and creates a 3D visualization of the semantic concept flows through corpus for interactive concept exploration. Finally, we illustrate the framework’s utility to extract the information from a text corpus of Herman Melville’s novel Moby Dick, the transcript of the 2015–2016 United States (U.S.) Senate Hearings on Environment and Public Works, and the Australian Broadcast Corporation’s short news articles on rural and science topics.

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Stepan, Lenka L., Daniel S. Levi, and Gregory P. Carman. "A Thin Film Nitinol Heart Valve." Journal of Biomechanical Engineering 127, no. 6 (July 6, 2005): 915–18. http://dx.doi.org/10.1115/1.2049311.

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In order to create a less thrombogenic heart valve with improved longevity, a prosthetic heart valve was developed using thin film nitinol (NiTi). A “butterfly” valve was constructed using a single, elliptical piece of thin film NiTi and a scaffold made from Teflon tubing and NiTi wire. Flow tests and pressure readings across the valve were performed in vitro in a pulsatile flow loop. Bio-corrosion experiments were conducted on untreated and passivated thin film nitinol. To determine the material’s in vivo biocompatibility, thin film nitinol was implanted in pigs using stents covered with thin film NiTi. Flow rates and pressure tracings across the valve were comparable to those through a commercially available 19 mm Perimount Edwards tissue valve. No signs of corrosion were present on thin film nitinol samples after immersion in Hank’s solution for one month. Finally, organ and tissue samples explanted from four pigs at 2, 3, 4, and 6 weeks after thin film NiTi implantation appeared without disease, and the thin film nitinol itself was without thrombus formation. Although long term testing is still necessary, thin film NiTi may be very well suited for use in artificial heart valves.

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NAM, JAEWOOK, and MARCIO S. CARVALHO. "Mid-gap invasion in two-layer slot coating." Journal of Fluid Mechanics 631 (July 17, 2009): 397–417. http://dx.doi.org/10.1017/s0022112009007022.

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Multi-layer, continuous liquid coating is the most efficient way to manufacture films that require more than one layer for optimal performance. Dual-layer slot coating is one of different coating methods largely used to deposit two thin, uniform liquid layers on to a moving substrate. The two liquid phases are separated by an inter-layer that starts at the separation point (or line, in three dimensions) attached to the die surface. The stability of the two-phase flow and the location of the separation point are directly related to the quality of the final product. Ideally, the separation point should be attached to the downstream corner of the mid die piece of a dual slot-coating die. However, its location may change as operating conditions vary, leading to undesired flow states, with microvortices and periodic oscillation. The movement of the separation point from its desired location along the die surface is usually referred to as mid-gap invasion and can be associated with the onset of coating defects. It is crucial to determine the set of flow conditions at which it occurs. We study the evolution of the separation-point location and the inter-layer configuration as a function of operating conditions by flow visualization and by solving the two-dimensional Navier–Stokes equation for free-surface flows. The results reveal two different mechanisms for mid-gap invasion, depending on the viscosity ratio of the two liquid layers. They also show that the most critical parameter responsible for the onset of mid-gap invasion is the bottom-layer wet thickness (flow rate). Although the movement of the separation point involves an evolution of complex flow states, a simple but accurate criterion based on rectilinear flow approximation is proposed.

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Wu, Wang Ping, Zhao Feng Chen, Jie Ming Zhou, and Xue Yu Cheng. "Thermal Properties of Vacuum Insulation Panels with Glass Fiber." Advanced Materials Research 446-449 (January 2012): 3753–56. http://dx.doi.org/10.4028/www.scientific.net/amr.446-449.3753.

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The VIPs consist of the glass-fiber core material and two types of envelope film. The glass fiber was fabricated by a centrifugal blowing process. The core material was prepared by the wet method. The thermal conductivities of the core material and VIPs were measured by the heat flow meter. The thermal conductivity for six pieces of 1mm thick core material is less than that for one piece of 6mm thick core material, which is affected by the fiber diameter, porosity ratio and the largest pore size diameter. The VIP for the building material has a low thermal conductivity (<0.008W/mK). The VIP for the home appliance has a lower thermal conductivity (<0.003W/mK). The VIP maintains a high-uniform thermal conductivity values due to the getter effect.

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Jung, Dong Won, Dong Hong Kim, Bong Chun Kim, Dae Lim Ko, and Duc Toan Nguyen. "A Development of Lancing Engineering Method for Lamp-CAN Stamping Process by Using Forming Analysis." Advanced Materials Research 337 (September 2011): 443–47. http://dx.doi.org/10.4028/www.scientific.net/amr.337.443.

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The products manufactured by the Sheet metal process are widely used in automobile and aircraft industries due to their high strength and superior surface characteristics. In this study, to improve the formability of the lamp-can, forming process was conducted using the Lancing engineering method. Lancing process is a press operation in which the work-piece is sheared and cut with one strike of the die to be a single-line cut or split, without removing any metal. Finite element method (FEM) was used to predict and investigate the improvement of formability of a lam-can with lancing process. As a result, it is believed that the Lancing process used in lamp-can forming would be helpful in the development of high-quality forming products because it can make material flow run well.

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Latorre, R., and R. Baubeau. "Numerical Study of Wall Influence on Boundary-Layer Transition for Two-Dimensional NACA 16-012 and 4412 Hydrofoil Sections." Journal of Ship Research 34, no. 01 (March 1, 1990): 38–47. http://dx.doi.org/10.5957/jsr.1990.34.1.38.

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One of the difficulties in hydrofoil model tests is the relatively low Reynolds number of the test piece and the presence of the test section walls. This paper presents the results of systematic calculations of the potential flow field of NA 4412 and NACA 16-012 hydrofoil in a test section with wall-to-chord ratios h/c -1.0. The corresponding boundary-layer calculations using the CERT calculation scheme are presented to show the influence of the nearby walls on shifting the location of the boundary-layer laminar-turbulent separation as well as turbulent separation. By introducing an effective angle of attack, it is possible to obtain close agreement in the calculated and measured suction side pressure distortion as well as the locations of the boundary-layer separation and transition.

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Altemeier, William A., Steve McKinney, and Robb W. Glenny. "Fractal nature of regional ventilation distribution." Journal of Applied Physiology 88, no. 5 (May 1, 2000): 1551–57. http://dx.doi.org/10.1152/jappl.2000.88.5.1551.

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High-resolution measurements of pulmonary perfusion reveal substantial spatial heterogeneity that is fractally distributed. This observation led to the hypothesis that the vascular tree is the principal determinant of regional blood flow. Recent studies using aerosol deposition show similar ventilation heterogeneity that is closely correlated with perfusion. We hypothesize that ventilation has fractal characteristics similar to blood flow. We measured regional ventilation and perfusion with aerosolized and injected fluorescent microspheres in six anesthetized, mechanically ventilated pigs in both prone and supine postures. Adjacent regions were clustered into progressively larger groups. Coefficients of variation were calculated for each cluster size to determine fractal dimensions. At the smallest size lung piece, local ventilation and perfusion are highly correlated, with no significant difference between ventilation and perfusion heterogeneity. On average, the fractal dimension of ventilation is 1.16 in the prone posture and 1.09 in the supine posture. Ventilation has fractal properties similar to perfusion. Efficient gas exchange is preserved, despite ventilation and perfusion heterogeneity, through close correlation. One potential explanation is the similar geometry of bronchial and vascular structures.

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Kulkarni, Mohan, Sunil Dingare, and Chandrakant Kulkarni. "Modeling, Simulation and Analysis of Tapered Receiver Utilization in Solar Cycloidal Concentrating System for Enhancement of System Efficiency." International Journal of Heat and Technology 39, no. 2 (April 30, 2021): 550–58. http://dx.doi.org/10.18280/ijht.390225.

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This paper presents modeling, simulation and analysis of heat transfer and fluid flow in the tapered receiver used in solar cycloidal concentrating system which is a novel concept. The main objective of this paper is to analyze performance of solar cycloidal concentrating system by utilizing novel concept of tapered receiver for enhancement of system efficiency. This solar cycloidal concentrating system is used for testing purpose from Jan 20-April 20 in Pune city, India. The calibrated device Pyranometer is used to provide values of solar irradiance. Readings are taken daily after each one hour for the whole day. Modeling of the tapered receiver tube which is novelty of this research is done using SOLIDWORKS software. The governing equations of fluid flow and heat transfer in the system are solved by using ANSYS-CFX CFD software. The obtained results show efficiency increment and rise in temperature. Experimental results and analysis using software shows that using novel concept of tapered receiver, there is noticeable decrement in thermal losses as there is decrement in the area of receiver from inlet to outlet of receiver tube and hence increase in the efficiency is observed. The tapered receiver is designed in such a way that, the entire receiver tube of 20 feet is cut into a separate 20 pieces. Each piece is having 304.80 mm in long. Total 20 pieces are separately designed for manufacturing of taper receiver. For each piece cut of 0.9 mm from inlet to outlet is taken for OD as well as for ID using CNC machine. Tapered receiver was manufactured by using various operations which includes MS rod cutting, machining, welding, arrangement for sensor fitting at said location and end nozzles.

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Bessone, Lucas, Joan Soler-Guitart, and Pablo Gamazo. "A parallelized algorithm to speed up 1D free-surface flow simulations in irrigation canals." Journal of Hydroinformatics 22, no. 6 (September 17, 2020): 1620–39. http://dx.doi.org/10.2166/hydro.2020.049.

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Abstract A parallel algorithm for 1D free-surface flow simulations in irrigation canals is shown. The model is based on the Hartree method applied to Saint-Venant equations. Due to the close-to-steady flow nature in irrigation canals, external and internal boundary conditions are linearized to preserve the parallel character. Gate trajectories, off-take withdrawals, and external boundary conditions are modeled as piece-wise functions of time, so there are discontinuities. To achieve a fully parallelized algorithm, an explicit version of the Hartree method is chosen, and external and internal boundary conditions are linearized around operation point. This approach is used to build a computer simulator, written in C-CUDA language. Two tests by ASCE Committee on Canal Automation Algorithms have been used to evaluate accuracy and performance of the algorithm. The Maricopa Stanfield benchmark has been used to prove its accuracy, and the Corning Canal benchmark to evaluate performance in terms of processing time. Surprisingly, solving a 12 hr-long prediction horizon with a cell size of about Δx= 10 m is less than 1 s on a Nvidia K40 card. Results were compared with a serial and a multi-CPU version of the same algorithm. The implementation that showed the best performance on different platforms is the one that uses GPU.

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Belchev, B., S. G. Neale, and M. A. Walton. "Flow of S-matrix poles for elementary quantum potentials1This research was supported in part by an NSERC Undergraduate Summer Research Award (SGN) and an NSERC Discovery Grant (MAW)." Canadian Journal of Physics 89, no. 11 (November 2011): 1127–40. http://dx.doi.org/10.1139/p11-107.

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The poles of the quantum scattering matrix (S-matrix) in the complex momentum plane have been studied extensively. Bound states give rise to S-matrix poles, and other poles correspond to non-normalizable antibound, resonance, and antiresonance states. They describe important physics but their locations can be difficult to determine. In pioneering work, Nussenzveig (Nucl. Phys. 11, 499 (1959)) performed the analysis for a square well (wall), and plotted the flow of the poles as the potential depth (height) varied. More than fifty years later, however, little has been done in the way of direct generalization of those results. We point out that today we can find such poles easily and efficiently using numerical techniques and widely available software. We study the poles of the scattering matrix for the simplest piecewise flat potentials, with one and two adjacent (nonzero) pieces. For the finite well (wall) the flow of the poles as a function of the depth (height) recovers the results of Nussenzveig. We then analyze the flow for a potential with two independent parts that can be attractive or repulsive, the two-piece potential. These examples provide some insight into the complicated behavior of the resonance, antiresonance, and antibound poles.

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Ran, Ranjiangshang, Quentin Brosseau, Brendan C. Blackwell, Boyang Qin, Rebecca L. Winter, and Paulo E. Arratia. "Bacteria hinder large-scale transport and enhance small-scale mixing in time-periodic flows." Proceedings of the National Academy of Sciences 118, no. 40 (September 27, 2021): e2108548118. http://dx.doi.org/10.1073/pnas.2108548118.

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Understanding mixing and transport of passive scalars in active fluids is important to many natural (e.g., algal blooms) and industrial (e.g., biofuel, vaccine production) processes. Here, we study the mixing of a passive scalar (dye) in dilute suspensions of swimming Escherichia coli in experiments using a two-dimensional (2D) time-periodic flow and in a simple simulation. Results show that the presence of bacteria hinders large-scale transport and reduces overall mixing rate. Stretching fields, calculated from experimentally measured velocity fields, show that bacterial activity attenuates fluid stretching and lowers flow chaoticity. Simulations suggest that this attenuation may be attributed to a transient accumulation of bacteria along regions of high stretching. Spatial power spectra and correlation functions of dye-concentration fields show that the transport of scalar variance across scales is also hindered by bacterial activity, resulting in an increase in average size and lifetime of structures. On the other hand, at small scales, activity seems to enhance local mixing. One piece of evidence is that the probability distribution of the spatial concentration gradients is nearly symmetric with a vanishing skewness. Overall, our results show that the coupling between activity and flow can lead to nontrivial effects on mixing and transport.

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Hinder, Murray, Alistair McEwan, Thomas Drevhammer, Snorri Donaldson, and Mark Brian Tracy. "T-piece resuscitators: how do they compare?" Archives of Disease in Childhood - Fetal and Neonatal Edition 104, no. 2 (May 4, 2018): F122—F127. http://dx.doi.org/10.1136/archdischild-2018-314860.

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BackgroundThe T-piece resuscitator (TPR) has seen increased use as a primary resuscitation device with newborns. Traditional TPR design uses a high resistance expiratory valve to produce positive end expiratory pressure (PEEP) or continuous positive airway pressure (CPAP) at resuscitation. A new TPR device that uses a dual flow ratio valve (fluidic flip) to produce PEEP/CPAP is now available (rPAP). We aimed to compare the measured ventilation performance of different TPR devices in a controlled bench test study.Design/methodsSingle operator provided positive pressure ventilation to an incremental testlung compliance (Crs) model (0.5–5 mL/cmH2O) with five different brands of TPR device (Atom, Neopuff, rPAP, GE Panda warmer and Draeger Resuscitaire). At recommended peak inflation pressure (PIP) 20 cmH2O, PEEP of 5 cmH2O and rate of 60 inflations per minute.Results1864 inflations were analysed. Four of the five devices tested demonstrated inadvertent elevations in mean PEEP (5.5–10.3 cmH2O, p<0.001) from set value as Crs was increased, while one device (rPAP) remained at the set value. Measured PIP exceeded the set value in two infant warmer devices (GE and Draeger) with inbuilt TPR at Crs of 0.5 (24.5 and 23.5 cmH2O, p<0.001). Significant differences were seen in tidal volumes across devices particularly at higher Crs (p<0.001).ConclusionsResults show important variation in delivered ventilation from set values due to inherent TPR device design characteristics with a range of lung compliances expected at birth. Device-generated inadvertent PEEP and overdelivery of PIP may be clinically deleterious for term and preterm newborns or infants with larger Crs during resuscitation.

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Gentil-Nunes, Pauxy. "Reading Textural Functions, Instrumental Techniques, and Space Through Partition Complexes." MusMat: Brazilian Journal of Music and Mathematics IV, no. 2 (December 28, 2020): 80–97. http://dx.doi.org/10.46926/musmat.2020v4n2.80-97.

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Partitional complexes are sets of discrete textural configurations (called shortly of partitions in Partition Analysis) that successfully interact to construct a global textural structure. This textural mode is called the Textural Proposal of a piece, where referential partitions (those that represent the main features of textural configurations in the excerpt) stand out. This conceptual environment, developed in musical texture formalization through observation and musical repertoire analysis, is now applied to musical practice. In the present work, we highlight three of these situations. The first one deals with the creative flow (compositional process) and its relation with textural planning. The second observes how these same textural functions condition the body's physical coupling to the instrument (fingers, hands, pedals, instrumentation). Finally, just as an introduction, we envisage some spatial relations, involving instrument distribution on stage, emphasizing historical concert music.

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Li, Tao, Xianhao Bao, Jiaxuan Feng, Zhenjiang Li, Junjun Liu, Yuxi Zhao, Mingwei Wu, et al. "Endovascular Reconstruction from Aortic Valve to Aortic Arch Using One-Piece Valved-Fenestrated Stent Graft with a Branch: A Proof-of-Concept Study." Heart Surgery Forum 22, no. 5 (September 16, 2019): E380—E384. http://dx.doi.org/10.1532/hsf.2585.

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Objective: To explore the feasibility of endovascular reconstruction of aortic root including aortic valve, sinus of valsalva and ascending aorta by a single stent-graft, a novel valved stent-graft with two fenestrae for preserving the coronary arteries was designed and performed in-vitro on a pig heart based circulation simulating system. Methods: Pig hearts were harvested from 30 healthy adult female pigs weighing between 60-65 kilograms. Before sacrifice, all the pigs received aortic computed tomography angiography (CTA) examinations and morphologic parameters of aortic root were measured. Then we customized the valved stent-grafts according to the CTA measurements. After the pig heart was fixed on the special platform according to the original orientation and connected to the circulation system, the stent graft was delivered through transapical access and covered the segment from aortic annulus to proximal part of aortic arch under DSA (digital subtraction angiography) guidance. Then changes of coronary flow before and after the procedure and fenestration alignment with coronary ostia were analyzed. Results: The overall technical success rate was 100%. The valve functions tested by ultrasound were in good condition under 120 mmHg circulation pressure. The flow of left coronary artery (LCA) did not decrease, but increased after the stent-graft implantation (340 ± 2.06 mL/min versus 288 ± 5.29 mL/min, P < .05). Similarly, the flow of right coronary artery (RCA) also increased (392 ± 9.17 mL/min versus 348 ± 8.01 mL/min; P < .05). The final angiography confirmed that both coronary arteries were patent. When generally observed from outer wall of valsalva sinus, both RCA and LCA orifices were aligned with the fenestrae. In 4 cases, the autologous valve leaflets blocked nearly 20% of the LCA fenestra’s area, but the flow did not significantly decrease in these cases. Conclusion: Stimulated on a pig heart-based circulation simulation system, the one-piece valved-fenestrated stent graft with a branch could be delivered via the transapical access and deployed accurately, which achieved endovascular reconstruction of aortic valve, sinus of valsalva and ascending aorta while preserving the coronary artery perfusion by fenestrations. More in-vivo experiments on animal models are mandatory to further verify its efficacy and safety.

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Agrawal, A. K., J. S. Kapat, and T. T. Yang. "An Experimental/Computational Study of Airflow in the Combustor–Diffuser System of a Gas Turbine for Power Generation." Journal of Engineering for Gas Turbines and Power 120, no. 1 (January 1, 1998): 24–33. http://dx.doi.org/10.1115/1.2818084.

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This paper presents an experimental/computational study of cold flow in the combustor–diffuser system of industrial gas turbines employing can-annular combustors and impingement-cooled transition pieces. The primary objectives were to determine flow interactions between the prediffuser and dump chamber, to evaluate circumferential flow nonuniformities around transition pieces and combustors, and to identify the pressure loss mechanisms. Flow experiments were conducted in an approximately one-third geometric scale, 360-deg annular test model simulating practical details of the prototype including the support struts, transition pieces, impingement sleeves, and can-annular combustors. Wall static pressures and velocity profiles were measured at selected locations in the test model. A three-dimensional computational fluid dynamic analysis employing a multidomain procedure was performed to supplement the flow measurements. The complex geometric features of the test model were included in the analysis. The measured data correlated well with the computations. The results revealed strong interactions between the prediffuser and dump chamber flows. The prediffuser exit flow was distorted, indicating that the uniform exit conditions typically assumed in the diffuser design were violated. The pressure varied circumferentially around the combustor casing and impingement sleeve. The circumferential flow nonuniformities increased toward the inlet of the turbine expander. A venturi effect causing flow to accelerate and decelerate in the dump chamber was also identified. This venturi effect could adversely affect impingement cooling of the transition piece in the prototype. The dump chamber contained several recirculation regions contributing to the losses. Approximately 1.2 dynamic head at the prediffuser inlet was lost in the combustor–diffuser, much of it in the dump chamber where the fluid passed though narrow pathways. A realistic test model and three-dimensional analysis used in this study provided new insight into the flow characteristics of practical combustor–diffuser systems.

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Zhao, Jian Hua, and Dian Rong Gao. "Analysis for Coupling Relationship of Oil Pocket under Eccentric Load in Hydrostatic Worktable." Applied Mechanics and Materials 233 (November 2012): 28–34. http://dx.doi.org/10.4028/www.scientific.net/amm.233.28.

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The oil pocket of the hydrostatic worktable in the modern heavy numerical control (NC) machine tools is designed under the circumstance that the working load acts equally on the oil pockets. But when the work piece is out of the rotary center of the worktable, the working load acts unequally on the oil pockets, and then the performance indexes for the oil pockets, such as acting force, oil film thickness, hydraulic damping, rated flow, are different. Based on the eccentric working load, under the circumstance that the oil pocket provides the fluid oil with constant pressure and constant flow mode, the coupling relationship between the oil pockets is analyzed, and the expression and the relatively bar graphics are presented. To achieve the machining quality and to prevent against the totally worn-out of the machine tools, it is best to adjust one oil pocket in order to keep the oil film of all oil pockets at the same thickness. While one oil pocket is adjusted, the oil pockets are intercoupling, and then the performance indexes change synchronously. According to the characteristics of the oil pocket in the hydrostatic worktable, the expression on the coupling relationship for the oil pocket is derived, then the performance indexes are analyzed qualitatively and the curves are plotted. The proposed research analyzed qualitatively the coupling relationship on the performance indexes for the constant pressure and the constant flow oil pockets separately in the worktable. It can improve the design efficiency and the accuracy with the help of the computer programs, and provides the reference for the practical engineering.

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Larsson, Jonas, Joel Peterson, and Heikki Mattila. "The knit on demand supply chain." Autex Research Journal 12, no. 3 (November 12, 2012): 67–75. http://dx.doi.org/10.2478/v10304-012-0013-9.

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The knit on demand supply chain As customers’ tastes become more differentiated, so must companies’ offerings evolve. The demand for variety may soon become unmanageable, and several companies are addressing this trend by adopting a system of mass customization. One project, Knit on Demand, has been conducted by the Swedish School of Textiles in close collaboration with a knitting company and a retailer of tailored fashion in Stockholm. Production and sales of customized products pose logistical challenges for the companies involved, including the one-piece flow through almost the entire supply chain and the demand for short lead times in an otherwise slow environment, adding to the cost of manufacturing mass customized garments. Customization has logistical benefits such as minimised inventory; hence, high inventory turnover and the possibility of fast response to meet customer demand. The Knit on Demand concept can be considered as leagile because it comprises both lean and agile components. It is lean in the manufacturing stage upstream and agile downstream to better respond to customer demand on the market.

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Christopoulos, D., and Lucia Quaglia. "Network Constraints in EU Banking Regulation: The Capital Requirements Directive." Journal of Public Policy 29, no. 2 (July 3, 2009): 179–200. http://dx.doi.org/10.1017/s0143814x09001068.

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AbstractThe ongoing financial turmoil has brought into sharp relief the importance of financial services regulation. Yet, we still know relatively little about how financial regulation is negotiated within the EU, in particular which policy actors are most influential and what are the mechanisms that allow them to exercise influence. This paper addresses these questions using Social Network Analysis (SNA), focusing on the banking regulation network and one core piece of legislation: the Capital Requirements Directive (CRD). Of particular interest is the flow of influence among the key actors. Triangulating an in-depth case study with qualitative interview data and social network analysis, this work investigates a number of hypotheses, associating brokerage roles and extroversion with relative influence in the policy making process. We find that influential actors are those that hold key structural positions in this network and by implication appear to have a better understanding of network topography.

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Journal articles on the topic 'One-Piece-Flow'

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