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Sample records for waterjet propelled craft

  1. Dimensionless Numerical Approaches for the Performance Prediction of Marine Waterjet Propulsion Units

    Directory of Open Access Journals (Sweden)

    Marco Altosole

    2012-01-01

    Full Text Available One of the key issues at early design stage of a high-speed craft is the selection and the performance prediction of the propulsion system because at this stage only few information about the vessel are available. The objective of this work is precisely to provide the designer, in the case of waterjet propelled craft, with a simple and reliable calculation tool, able to predict the waterjet working points in design and off-design conditions, allowing to investigate several propulsive options during the ship design process. In the paper two original dimensionless numerical procedures, one referred to jet units for naval applications and the other more suitable for planing boats, are presented. The first procedure is based on a generalized performance map for mixed flow pumps, derived from the analysis of several waterjet pumps by applying similitude principles of the hydraulic machines. The second approach, validated by some comparisons with current waterjet installations, is based on a complete physical approach, from which a set of non-dimensional waterjet characteristics has been drawn by the authors. The presented application examples show the validity and the degree of accuracy of the proposed methodologies for the performance evaluation of waterjet propulsion systems.

  2. Numerical analysis of a waterjet propulsion system

    NARCIS (Netherlands)

    Bulten, N.W.H.

    2006-01-01

    A waterjet propulsion system is used to propel ships, using a pump which produces a high speed jet. A standard waterjet installation can be divided into an inlet, a pump and a nozzle. For manoeuvring and reversing purposes an additional steering device can be integrated into the installation. The

  3. CRAFT

    DEFF Research Database (Denmark)

    Gammelgaard Nielsen, Anders

    2012-01-01

    At the Aarhus School of Architecture, Associate Professor Anders Gammelgaard has erected a solid wood construction, based on traditional craftsmanship. The entire structure is made of heavy oak timber that is joined together using the old techniques of tongue and groove and dowels. The motivation......-air museums, as a performing art in front of an audience. In this article the author discusses the importance of craft and craftsmanship in contemporary architecture in relation to its users....

  4. Design Method for Contra-Rotating Propellers for High-Speed Crafts: Revising the Original Lerbs Theory in a Modern Perspective

    Directory of Open Access Journals (Sweden)

    Stefano Brizzolara

    2012-01-01

    Full Text Available The main theoretical and numerical aspects of a design method for optimum contrar-rotating (CR propellers for fast marine crafts are presented. We propose a reformulated version of a well-known design theory for contra-rotating propellers, by taking advantage of a new fully numerical algorithm for the calculation of the mutually induced velocities and introducing new features such as numerical lifting surface corrections, use of an integrated modern cavitation/strength criteria, a modified method to consider different numbers of blades among the two propellers, and to allow for an unloading function in the search for the optimal circulation distribution. The paper first introduces the main theoretical principles of the new methods and then discusses the influence of the main design parameters on an emblematic example of application in the case of counter rotating propellers for a pod propulsor designed for fast planing crafts (35 knots and above.

  5. Sandstone Turning by Abrasive Waterjet

    Czech Academy of Sciences Publication Activity Database

    Hlaváček, Petr; Cárach, J.; Hloch, Sergej; Vasilko, K.; Klichová, Dagmar; Klich, Jiří; Lehocká, D.

    2015-01-01

    Roč. 48, č. 6 (2015), s. 2489-2493 ISSN 0723-2632 R&D Projects: GA MŠk ED2.1.00/03.0082; GA MŠk(CZ) LO1406 Institutional support: RVO:68145535 Keywords : turning away from the jet * conventional turning towards the jet * sandstone * abrasive water jet Subject RIV: JQ - Machines ; Tools Impact factor: 2.386, year: 2015 http://www.springerprofessional.de/sandstone-turning-by-abrasive-waterjet/6038028.html

  6. Performance Enhancement of Abrasive Waterjet Cutting

    NARCIS (Netherlands)

    2008-01-01

    Abrasive Waterjet (AWJ) Machining is a recent non-traditional machining process. This technology is widely used in industry for cutting difficult-to-machine-materials, milling slots, polishing hard materials etc. AWJ machining has many advantages, e.g. it can cut net-shape parts, no heat is

  7. Using waterjet in reverse logistic operations in discarded munitions processing

    Czech Academy of Sciences Publication Activity Database

    Hloch, S.; Tozan, H.; Yagimli, M.; Valíček, Jan; Rokosz, K.

    2011-01-01

    Roč. 18, č. 2 (2011), s. 267-271 ISSN 1330-3651 Institutional research plan: CEZ:AV0Z30860518 Keywords : abrasive waterjet * anti tank bullet * automatic line Subject RIV: JQ - Machines ; Tools Impact factor: 0.347, year: 2011 http://hrcak.srce.hr/search/?q=Using+waterjet+in+reverse+logistic+operations+in+discarded+munitions+processing

  8. Abrasives and possibilities of increase in efficiency of abrasive waterjets

    Czech Academy of Sciences Publication Activity Database

    Sitek, Libor; Martinec, Petr

    2016-01-01

    Roč. 9, March 2016 (2016), s. 877-881 ISSN 1805-0476 R&D Projects: GA MŠk(CZ) LO1406; GA MŠk ED2.1.00/03.0082 Institutional support: RVO:68145535 Keywords : high-speed waterjets * abrasive waterjets * abrasives * garnet * zirconia Subject RIV: JQ - Machines ; Tools http://www.mmscience.eu/content/file/archives/MM_Science_201603.pdf

  9. Transformation Craft (T-Craft) Concept Study

    National Research Council Canada - National Science Library

    Marks, Cynthia; Phelps, Chance; Ryan, Justin; Sorensen, Paul

    2007-01-01

    The objective of the Transformation Craft (T-Craft) innovation team was to develop a conceptual craft that addresses the problem of transporting military vehicles at high speed from the Sea Base to troops inland...

  10. Space Craft

    Science.gov (United States)

    Demski, Jennifer

    2009-01-01

    This article discusses how craft innovative architecture is bringing form to the function of 21st-century learning. It describes the construction of New Tech High at Coppell, in Coppell, Texas, which produces an example of how workplace design principles can be coordinated with modern educational goals. The campus was built on the model of New…

  11. Waterjet cutting of periprosthetic interface tissue in loosened hip prostheses: an in vitro feasibility study

    NARCIS (Netherlands)

    Kraaij, Gert; Tuijthof, Gabrielle J. M.; Dankelman, Jenny; Nelissen, Rob G. H. H.; Valstar, Edward R.

    2015-01-01

    Waterjet cutting technology is considered a promising technology to be used for minimally invasive removal of interface tissue surrounding aseptically loose hip prostheses. The goal of this study was to investigate the feasibility of waterjet cutting of interface tissue membrane. Waterjets with 0.2

  12. Contextualising Craft: Pedagogical Models for Craft Education

    Science.gov (United States)

    Pollanen, Sinikka

    2009-01-01

    Craft education in Finland is, in many aspects, in a state of change. This concerns the independent position of craft as a school subject, the content of the compulsory craft courses containing textiles and technical work, the implementation of the new concept of a holistic craft process in the National Core Curriculum and so on. This bears…

  13. Mixed-Flow Waterjet (MxWJ) Model 5662-1: Initial Study of Yaw Effects on Waterjet Powering and Transom Depth Effects on Waterjet Priming

    National Research Council Canada - National Science Library

    Cusanelli, Dominic S

    2007-01-01

    ...: (1) The effects of model yaw angles on waterjet powering. Model-scale rotor force measurements of thrust and torque at angles of yaw up to 3 degrees showed little variation compared to the equivalent forces measured at zero yaw angle...

  14. Brane Craft

    Science.gov (United States)

    Janson, Siegfried

    2017-01-01

    A Brane Craft is a membrane spacecraft with solar cells, command and control electronics, communications systems, antennas, propulsion systems, attitude and proximity sensors, and shape control actuators as thin film structures manufactured on 10 micron thick plastic sheets. This revolutionary spacecraft design can have a thickness of tens of microns with a surface area of square meters to maximize area-to-mass ratios for exceptionally low-mass spacecraft. Communications satellites, solar power satellites, solar electric propulsion stages, and solar sails can benefit from Brane Craft design. It also enables new missions that require low-mass spacecraft with exceptionally high delta-V. Active removal of orbital debris from Earth orbit is the target application for this study.

  15. Abrasive-waterjet cutting of thick concrete and waterjet cleaning for nuclear facility decommissioning and decontamination

    International Nuclear Information System (INIS)

    Echert, D.C.; Hashish, M.; Marvin, M.H.

    1987-01-01

    Two tools have been developed for use by the nuclear industry: the Deep Kerf tool and the Cleaner/Scarifier tool. The Deep Kerf tool is designed to cut through thick, reinforced concrete structures to facilitate their decommissioning. It employs the abrasive-waterjet (AWJ) cutting technology. The basis of the system is a rotary nozzle that makes a slot in the concrete wide enough to accommodate the cutting tool as it advances. In this program, concrete as thick as 1.5 m was cut through from one side. A shroud and vacuum system covers the opening of the slot during cutting to contain the spoils with greater than 99% efficiency. The Cleaner/Scarifier tool was designed for removing the surface layers of contaminated concrete and decontaminating metal surfaces. It uses ultrahigh-pressure waterjets mounted on a rotating arm to remove or clean the target surface. Spoils recovery with a shroud and vacuum system is over 99% complete for both horizontal and vertical surfaces

  16. Breakthrough Energy Savings with Waterjet Technology

    Energy Technology Data Exchange (ETDEWEB)

    Lee W. Saperstein; R. Larry Grayson; David A. Summers; Jorge Garcia-Joo; Greg Sutton; Mike Woodward; T.P. McNulty

    2007-05-15

    Experiments performed at the University of Missouri-Rolla's Waterjet Laboratory have demonstrated clearly the ability of waterjets to disaggregate, in a single step, four different mineral ores, including ores containing iron, lead and copper products. The study focused mainly on galena-bearing dolomite, a lead ore, and compared the new technology with that of traditional mining and milling to liberate the valuable constituent for the more voluminous host rock. The technical term for the disintegration of the ore to achieve this liberation is comminution. The potential for energy savings if this process can be improved, is immense. Further, if this separation can be made at the mining face, then the potential energy savings include avoidance of transportation (haulage and hoisting) costs to move, process and store this waste at the surface. The waste can, instead, be disposed into the available cavities within the mine. The savings also include the elimination of the comminution, crushing and grinding, stages in the processing plant. Future prototype developments are intended to determine if high-pressure waterjet mining and processing can be optimized to become cheaper than traditional fragmentation by drilling and blasting and to optimize the separation process. The basic new mining process was illustrated in tests on two local rock types, a low-strength sandstone with hematite inclusions, and a medium to high-strength dolomite commonly used for construction materials. Illustrative testing of liberation of minerals, utilized a lead-bearing dolomite, and included a parametric study of the optimal conditions needed to create a size distribution considered best for separation. The target goal was to have 50 percent of the mined material finer than 100 mesh (149 microns). Of the 21 tests that were run, five clearly achieved the target. The samples were obtained as run-of-mine lumps of ore, which exhibited a great deal of heterogeneity within the samples. This

  17. Topographical anomaly on surfaces created by abrasive waterjet

    Czech Academy of Sciences Publication Activity Database

    Hloch, S.; Valíček, Jan

    2012-01-01

    Roč. 59, 5-8 (2012), s. 593-604 ISSN 0268-3768 Institutional research plan: CEZ:AV0Z30860518 Keywords : abrasive waterjet * initial zone * surface topography Subject RIV: JQ - Machines ; Tools Impact factor: 1.205, year: 2012 http://www.springerlink.com/content/5701144k76v02372

  18. Influence of Water-jet Nozzle Geometry on Cutting Ability of Soft Material

    Directory of Open Access Journals (Sweden)

    Irwansyah Irwansyah

    2012-06-01

    Full Text Available Hygiene is main reason for food processor to use waterjet cutting system. Traditionally food cutting process is low-quality, unsafe products, procedures and direct contact between product and labor. This paper introduced a low cost waterjet system for cutting soft material as identic food material. The low cost waterjet system has been developed by using a commercial pressure pump for cleaning purposes and modified nozzle. In order to enhance waterjet pressure for cutting products, a modified waterjet nozzle was designed. Paramater design of waterjet system was setup on nozzle orifice diameter 0.5 mm, standoff distance 15 mm, length of nozzle cylindrical tube 2.5 mm. Polycarbonate, polysterene, and polyethelene materials are used as sample product with thickness 2 mm, to represent similar properties with agriculture products. The experimental results indicate good possibilities of waterjet system to cut material in appropriate profile surface. The waterjet also can be used to improve cutting finished surface of food products. Therefore, utilizing a low cost commercial pump and modified nozzle for waterjet system reduces equipment price, operational cost and environmental hazards. It indicates viable technology applied to substitute traditional cutting technology in post harvest agriculture products. Keywords: cutting ability, modified nozzle, polymer material, water-jet system

  19. Integrated Bow Waterjet for Amphibious Vehicles.

    Science.gov (United States)

    1983-01-01

    8217 Davidson Laboratory Report 2276, October 1982. 3. J. D. van Manen , "Open-Water Test Series with Propellers in Nozzles," International Shipbuilding Progress...Volume 1, No. 2, 1954, pg. 99. 4. W.P.A. van Lammeren, J. D. van Manen and M.W.C. Oosterveld, "The Wageningen B-Screw Series," Trans. SNAME 1969, pg

  20. Performance Analysis of Abrasive Waterjet Machining Process at Low Pressure

    Science.gov (United States)

    Murugan, M.; Gebremariam, MA; Hamedon, Z.; Azhari, A.

    2018-03-01

    Normally, a commercial waterjet cutting machine can generate water pressure up to 600 MPa. This range of pressure is used to machine a wide variety of materials. Hence, the price of waterjet cutting machine is expensive. Therefore, there is a need to develop a low cost waterjet machine in order to make the technology more accessible for the masses. Due to its low cost, such machines may only be able to generate water pressure at a much reduced rate. The present study attempts to investigate the performance of abrasive water jet machining process at low cutting pressure using self-developed low cost waterjet machine. It aims to study the feasibility of machining various materials at low pressure which later can aid in further development of an effective low cost water jet machine. A total of three different materials were machined at a low pressure of 34 MPa. The materials are mild steel, aluminium alloy 6061 and plastics Delrin®. Furthermore, a traverse rate was varied between 1 to 3 mm/min. The study on cutting performance at low pressure for different materials was conducted in terms of depth penetration, kerf taper ratio and surface roughness. It was found that all samples were able to be machined at low cutting pressure with varied qualities. Also, the depth of penetration decreases with an increase in the traverse rate. Meanwhile, the surface roughness and kerf taper ratio increase with an increase in the traverse rate. It can be concluded that a low cost waterjet machine with a much reduced rate of water pressure can be successfully used for machining certain materials with acceptable qualities.

  1. Hydrochromic molecular switches for water-jet rewritable paper

    Science.gov (United States)

    Sheng, Lan; Li, Minjie; Zhu, Shaoyin; Li, Hao; Xi, Guan; Li, Yong-Gang; Wang, Yi; Li, Quanshun; Liang, Shaojun; Zhong, Ke; Zhang, Sean Xiao-An

    2014-01-01

    The days of rewritable paper are coming, printers of the future will use water-jet paper. Although several kinds of rewritable paper have been reported, practical usage of them is rare. Herein, a new rewritable paper for ink-free printing is proposed and demonstrated successfully by using water as the sole trigger to switch hydrochromic dyes on solid media. Water-jet prints with various colours are achieved with a commercial desktop printer based on these hydrochromic rewritable papers. The prints can be erased and rewritten dozens of times with no significant loss in colour quality. This rewritable paper is promising in that it can serve an eco-friendly information display to meet the increasing global needs for environmental protection.

  2. Waterjet cutting of periprosthetic interface tissue in loosened hip prostheses: an in vitro feasibility study.

    Science.gov (United States)

    Kraaij, Gert; Tuijthof, Gabrielle J M; Dankelman, Jenny; Nelissen, Rob G H H; Valstar, Edward R

    2015-02-01

    Waterjet cutting technology is considered a promising technology to be used for minimally invasive removal of interface tissue surrounding aseptically loose hip prostheses. The goal of this study was to investigate the feasibility of waterjet cutting of interface tissue membrane. Waterjets with 0.2 mm and 0.6 mm diameter, a stand-off distance of 5 mm, and a traverse speed of 0.5 mm/s were used to cut interface tissue samples in half. The water flow through the nozzle was controlled by means of a valve. By changing the flow, the resulting waterjet pressure was regulated. Tissue sample thickness and the required waterjet pressures were measured. Mean thickness of the samples tested within the 0.2 mm nozzle group was 2.3 mm (SD 0.7 mm) and within the 0.6 mm nozzle group 2.6 mm (SD 0.9 mm). The required waterjet pressure to cut samples was between 10 and 12 MPa for the 0.2 mm nozzle and between 5 and 10 MPa for the 0.6 mm nozzle. Cutting bone or bone cement requires about 3 times higher waterjet pressure (30-50 MPa, depending on used nozzle diameter) and therefore we consider waterjet cutting as a safe technique to be used for minimally invasive interface tissue removal. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

  3. Comparisons of Hydraulic Performance in Permanent Maglev Pump for Water-Jet Propulsion

    Directory of Open Access Journals (Sweden)

    Puyu Cao

    2014-08-01

    Full Text Available The operation of water-jet propulsion can generate nonuniform inflow that may be detrimental to the performance of the water-jets. To reduce disadvantages of the nonuniform inflow, a rim-driven water-jet propulsion was designed depending on the technology of passive magnetic levitation. Insufficient understanding of large performance deviations between the normal water-jets (shaft and permanent maglev water-jets (shaftless is a major problem in this paper. CFD was directly adopted in the feasibility and superiority of permanent maglev water-jets. Comparison and discussion of the hydraulic performance were carried out. The shaftless duct firstly has a drop in hydraulic losses (K1, since it effectively avoids the formation and evolution of the instability secondary vortex by the normalized helicity analysis. Then, the shaftless intake duct improves the inflow field of the water-jet pump, with consequencing the drop in the backflow and blocking on the blade shroud. So that the shaftless water-jet pump delivers higher flow rate and head to the propulsion than the shaft. Eventually, not only can the shaftless model increase the thrust and efficiency, but it has the ability to extend the working range and broaden the high efficiency region as well.

  4. Computer Crafts for Kids.

    Science.gov (United States)

    Kuntz, Margy; Kuntz, Ann

    This work presents a collection of craft projects that can be created by children. Necessary for completion of each craft is an IBM-compatible computer running Windows, "Word for Windows 6.0," with a mouse, a printer, and plain white printer paper. Simple craft supplies, including glue and scissors, also are needed. In each activity the child is…

  5. Experimental Research on the Specific Energy Consumption of Rock Breakage Using Different Waterjet-Assisted Cutting Heads

    Directory of Open Access Journals (Sweden)

    Hongxiang Jiang

    2018-01-01

    Full Text Available To investigate the specific energy consumption (SE of rock breakage by cutting heads assisted by different types of waterjet and to identify optimal waterjet parameters and assistance types, rock cutting with and without waterjets was carried on a rock fragmentation test bed. SE is a comprehensive evaluation index and was developed according to the applied load on cutting head, and the SE under different cutting conditions was compared and analyzed. The results show that the SE of rock breakage without waterjet assistance increased with the increasing of rock compressive strength (RCS but that the limited drilling depth decreased. The effect of the waterjet pressure on the SE of rock breakage by the cutting head I was marked, and SE decreased by 30∼40% when the ratio between RCS and waterjet pressure was less than 1. However, the function of the waterjet assistance was poor; therefore, a ratio of 1 could be used to distinguish the rock breakage effect of cutting head I. For cutting head II, the rock damage from the waterjet impact was limited due to the large waterjet standoff distance; thus the rock breakage performance of cutting head II was also limited. The waterjet impacting at the tip of the conical pick using cutting head III could enter into the cracks caused by the mechanical pick and fracture the rock. Therefore, the rock breakage performance of cutting head III was better than that of cutting head II.

  6. In Search of Craft

    Science.gov (United States)

    Schwalbe, Michael

    2010-01-01

    In the spring of 2009, this author asked the director of North Carolina State's Crafts Center to help him find people who might be willing to participate in a project about skill. Bill Wallace, an occasional teacher at the Crafts Center, was one of the people recommended to him. Bill Wallace is a man who can look at a tree and instinctively know…

  7. Comparative study on the performance of Pod type waterjet by experiment and computation

    Directory of Open Access Journals (Sweden)

    Moon-Chan Kim

    2010-03-01

    Full Text Available A comparative study between a computation and an experiment has been conducted to predict the performance of a Pod type waterjet for an amphibious wheeled vehicle. The Pod type waterjet has been chosen on the basis of the required specific speed of more than 2500. As the Pod type waterjet is an extreme type of axial flow type waterjet, theoretical as well as experimental works about Pod type waterjets are very rare. The main purpose of the present study is to validate and compare to the experimental results of the Pod type waterjet with the developed CFD in-house code based on the RANS equations. The developed code has been validated by comparing with the experimental results of the well-known turbine problem. The validation also extended to the flush type waterjet where the pressures along the duct surface and also velocities at nozzle area have been compared with experimental results. The Pod type waterjet has been designed and the performance of the designed waterjet system including duct, impeller and stator was analyzed by the previously mentioned in-house CFD Code. The pressure distributions and limiting streamlines on the blade surfaces were computed to confirm the performance of the designed waterjets. In addition, the torque and momentum were computed to find the entire efficiency and these were compared with the model test results. Measurements were taken of the flow rate at the nozzle exit, static pressure at the various sections along the duct and also the nozzle, revolution of the impeller, torque, thrust and towing forces at various advance speeds for the prediction of performance as well as for comparison with the computations. Based on these measurements, the performance was analyzed according to the ITTC96 standard analysis method. The full-scale effective and the delivered power of the wheeled vehicle were estimated for the prediction of the service speed. This paper emphasizes the confirmation of the ITTC96 analysis method and

  8. The influence of the waterjet propulsion system on the ships' energy consumption and emissions inventories.

    Science.gov (United States)

    Durán-Grados, Vanesa; Mejías, Javier; Musina, Liliya; Moreno-Gutiérrez, Juan

    2018-08-01

    In this study we consider the problems associated with calculating ships' energy and emission inventories. Various related uncertainties are described in many similar studies published in the last decade, and applying to Europe, the USA and Canada. However, none of them have taken into account the performance of ships' propulsion systems. On the one hand, when a ship uses its propellers, there is no unanimous agreement on the equations used to calculate the main engines load factor and, on the other, the performance of waterjet propulsion systems (for which this variable depends on the speed of the ship) has not been taken into account in any previous studies. This paper proposes that the efficiency of the propulsion system should be included as a new parameter in the equation that defines the actual power delivered by a ship's main engines, as applied to calculate energy consumption and emissions in maritime transport. To highlight the influence of the propulsion system on calculated energy consumption and emissions, the bottom-up method has been applied using data from eight fast ferries operating across the Strait of Gibraltar over the course of one year. This study shows that the uncertainty about the efficiency of the propulsion system should be added as one more uncertainty in the energy and emission inventories for maritime transport as currently prepared. After comparing four methods for this calculation, the authors propose a new method for eight cases. For the calculation of the Main Engine's fuel oil consumption, differences up to 22% between some methods were obtained at low loads. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Experiment and simulation study of laser dicing silicon with water-jet

    Energy Technology Data Exchange (ETDEWEB)

    Bao, Jiading; Long, Yuhong, E-mail: longyuhong@guet.edu.cn; Tong, Youqun; Yang, Xiaoqing; Zhang, Bin; Zhou, Zupeng

    2016-11-30

    Highlights: • The explosive melt expulsion could be a dominant process for the laser ablating silicon in liquids with ns-pulsed laser of 1064 nm irradiating. • Self-focusing phenomenon was found and its causes are analyzed. • SPH modeling technique was employed to understand the effect of water and water-jet on debris removal during water-jet laser machining. - Abstract: Water-jet laser processing is an internationally advanced technique, which combines the advantages of laser processing with water jet cutting. In the study, the experiment of water-jet laser dicing are conducted with ns pulsed laser of 1064 nm irradiating, and Smooth Particle Hydrodynamic (SPH) technique by AUTODYN software was modeled to research the fluid dynamics of water and melt when water jet impacting molten material. The silicon surface morphology of the irradiated spots has an appearance as one can see in porous formation. The surface morphology exhibits a large number of cavities which indicates as bubble nucleation sites. The observed surface morphology shows that the explosive melt expulsion could be a dominant process for the laser ablating silicon in liquids with nanosecond pulse laser of 1064 nm irradiating. Self-focusing phenomenon was found and its causes are analyzed. Smooth Particle Hydrodynamic (SPH) modeling technique was employed to understand the effect of water and water-jet on debris removal during water-jet laser machining.

  10. Implementing digital crafting : developing

    DEFF Research Database (Denmark)

    Tamke, Martin; Ramsgaard Thomsen, Mette

    2010 in the Danish Design Centre in Copenhagen. The exhibition presents 18 designers, architects and people from the crafts that have an innovative take on the future questions of sustainability, new materials and technology. Their products challenge traditional Danish Design and are yet interconnected...... in the countries traits and the way they design. Curated by the Danish Design Centre, The Danish Architectural Centre and the Danish Crafts Organisation groups of three from the different disciplines were identified in 6 scenarios with distinct expression....

  11. The meaning of craft: craft makers' descriptions of craft as an occupation.

    Science.gov (United States)

    Pöllänen, Sinikka

    2013-05-01

    The aim of this study is to examine how craft makers describe the meaning of craft as an activity in relation to their well-being. The study is based on an analysis of the written narratives of 92 textile craft makers aged 16 to 84. Based on the results, the well-being enhancing nature of craft as a meaningful occupation for those interested in crafting is evident. The significance of craft making as an occupation is described by the following three themes: (a) "the meaning and value of crafts", (b) "the feelings experienced during craft activity", and (c) "the holisticity and intentionality of craft-making". As an activity and a metaphor, craft making helped the participants to adjust to life situations. Elements of craft that enhance well-being can be traced to both the artefacts and the sense of achievement gained in producing them. The effects of craft include personal growth, development of physical and cognitive skills, control of one's body, thoughts, and feelings, as well as cultural and social awareness. The results indicate that the participants noticed the significance of craft as an agony- and stress-reducing and mind-calming activity. Holistic craft and ordinary craft played different roles in maintaining well-being.

  12. Waterjet drilling in porcine bone: the effect of the nozzle diameter and bone architecture on the hole dimensions

    NARCIS (Netherlands)

    den Dunnen, Steven; Mulder, Lars; Kerkhoffs, Gino M. M. J.; Dankelman, Jenny; Tuijthof, Gabrielle J. M.

    2013-01-01

    Using waterjets instead of rigid drill bits for bone drilling can be beneficial due to the absence of thermal damage and a consequent sharp cut. Additionally, waterjet technology allows the development of flexible instruments that facilitate maneuvering through complex joint spaces. Controlling the

  13. Experimental Study on Abrasive Waterjet Polishing of Hydraulic Turbine Blades

    International Nuclear Information System (INIS)

    Khakpour, H; Birglenl, L; Tahan, A; Paquet, F

    2014-01-01

    In this paper, an experimental investigation is implemented on the abrasive waterjet polishing technique to evaluate its capability in polishing of surfaces and edges of hydraulic turbine blades. For this, the properties of this method are studied and the main parameters affecting its performance are determined. Then, an experimental test-rig is designed, manufactured and tested to be used in this study. This test-rig can be used to polish linear and planar areas on the surface of the desired workpieces. Considering the number of parameters and their levels, the Taguchi method is used to design the preliminary experiments. All experiments are then implemented according to the Taguchi L 18 orthogonal array. The signal-to-noise ratios obtained from the results of these experiments are used to determine the importance of the controlled polishing parameters on the final quality of the polished surface. The evaluations on these ratios reveal that the nozzle angle and the nozzle diameter have the most important impact on the results. The outcomes of these experiments can be used as a basis to design a more precise set of experiments in which the optimal values of each parameter can be estimated

  14. Research on axial thrust of the waterjet pump based on CFD under cavitation conditions

    Science.gov (United States)

    Shen, Z. H.; Pan, Z. Y.

    2015-01-01

    Based on RANS equations, performance of a contra-rotating axial-flow waterjet pump without hydrodynamic cavitation state had been obtained combined with shear stress transport turbulence model. Its cavitation hydrodynamic performance was calculated and analysed with mixture homogeneous flow cavitation model based on Rayleigh-Plesset equations. The results shows that the cavitation causes axial thrust of waterjet pump to drop. Furthermore, axial thrust and head cavitation characteristic curve is similar. However, the drop point of the axial thrust is postponed by 5.1% comparing with one of head, and the critical point of the axial thrust is postponed by 2.6%.

  15. Research on axial thrust of the waterjet pump based on CFD under cavitation conditions

    International Nuclear Information System (INIS)

    Shen, Z H; Pan, Z Y

    2015-01-01

    Based on RANS equations, performance of a contra-rotating axial-flow waterjet pump without hydrodynamic cavitation state had been obtained combined with shear stress transport turbulence model. Its cavitation hydrodynamic performance was calculated and analysed with mixture homogeneous flow cavitation model based on Rayleigh-Plesset equations. The results shows that the cavitation causes axial thrust of waterjet pump to drop. Furthermore, axial thrust and head cavitation characteristic curve is similar. However, the drop point of the axial thrust is postponed by 5.1% comparing with one of head, and the critical point of the axial thrust is postponed by 2.6%

  16. Nuclear thermal rockets using indigenous Martian propellants

    International Nuclear Information System (INIS)

    Zubrin, R.M.

    1989-01-01

    This paper considers a novel concept for a Martian descent and ascent vehicle, called NIMF (for nuclear rocket using indigenous Martian fuel), the propulsion for which will be provided by a nuclear thermal reactor which will heat an indigenous Martian propellant gas to form a high-thrust rocket exhaust. The performance of each of the candidate Martian propellants, which include CO2, H2O, CH4, N2, CO, and Ar, is assessed, and the methods of propellant acquisition are examined. Attention is also given to the issues of chemical compatibility between candidate propellants and reactor fuel and cladding materials, and the potential of winged Mars supersonic aircraft driven by this type of engine. It is shown that, by utilizing the nuclear landing craft in combination with a hydrogen-fueled nuclear thermal interplanetary vehicle and a heavy lift booster, it is possible to achieve a manned Mars mission in one launch. 6 refs

  17. Josiah Wedgwood, Manufacturing and Craft

    DEFF Research Database (Denmark)

    Holt, Robin; Popp, Andrew

    2016-01-01

    Craft and industrial manufacture are often seen as dichotomous, with craft being marginalized during the process of industrialization. We want to look beyond this position, searching for craft in places where it has gone unnoticed and where it might have bloomed anew in the interstices created...

  18. The craft of screenwriting

    NARCIS (Netherlands)

    Weijers, G.W.M.

    2014-01-01

    Isn't it ironic? Screenwriting is not something you learn from a book, or a talent that just falls into your lap. Nevertheless, without talent you will never become a great scriptwriter. Above all scriptwriting is a craft that you learn to master by writing, reflecting, and rewriting time after

  19. Pure waterjet drilling of articular bone: an in vitro feasibility study.

    NARCIS (Netherlands)

    den Dunnen, Steven; Kraaij, Gert; Biskup, Christian; Kerkhoffs, Gino M. M. J.; Tuijthof, Gabriëlle J. M.

    2013-01-01

    The clinical application of waterjet technology for machining tough human tissues, such as articular bone, has advantages, as it produces clean sharp cuts without tissue heating. Additionally, water supply is possible via flexible tubing, which enables minimally invasive surgical access. This pilot

  20. Preliminary results of experimental cutting of porcine bones by abrasive waterjet

    Czech Academy of Sciences Publication Activity Database

    Hloch, S.; Valíček, Jan; Kozak, D.

    2011-01-01

    Roč. 18, č. 3 (2011), s. 467-470 ISSN 1330-3651 Institutional research plan: CEZ:AV0Z30860518 Keywords : abrasive waterjet cutting * porcine bones * surface quality Subject RIV: JQ - Machines ; Tools Impact factor: 0.347, year: 2011 http://hrcak.srce.hr/index.php?show=clanak&id_clanak_jezik=107026

  1. Multimedia Superabrasive, Laser Cladding, and Waterjet Technology Performance Support System

    International Nuclear Information System (INIS)

    Bohley, M.C.; Ciccateri, T.J.

    1998-01-01

    incorporated into the electronic information retrieval portion of the PSS. On-line reference manuals covering Operations, Maintenance, Mechanical, Electrical, and Peripherals provide text and illustrations to the machine operator in a traditional structure, but additionally offer the capability to search voluminous amounts of technical data and retrieve specific information on request. This project provided the project team with a detailed understanding of the knowledge and information required to produce and support advanced machine tools. In addition it resulted in the design and construction of a prototype Grinders PSS that contains all the logic and interfaces necessary to integrate product information from the Huffman Waterjets and Lasers product lines

  2. Air propellers and their environmental problems on ACV's

    Science.gov (United States)

    Soley, D. H.

    The development of ACV blade protection against erosion, both on the propeller blade faces and leading edge, is considered. Polyurethane spray coating is now the standard protection applied to all Dowty Rotol propellers, with thicknesses from 0.015-0.020 on aircraft, and up to 0.080 on the ACV. The bolt-on guard reduced leading edge replacement time by 50 percent, and makes possible replacement in all weather conditions. Typical damage and repairs to ACV blades are discussed, and the propeller installation on the LCAC craft being built for the U.S. Navy is addressed.

  3. Craft qualities translated from traditional crafts to smart textile services

    NARCIS (Netherlands)

    Kuusk, K.; Wensveen, S.A.G.; Tomico Plasencia, O.

    2016-01-01

    In this article we suggest craft and craftsmanship as an inspiration to design more sustainable smart textile services. We look into the opportunities that interactive properties and services bring into the textile and garment life cycle. We use traditional crafts as a source of inspiration for the

  4. Crafting digital media

    CERN Document Server

    James, Daniel

    2010-01-01

    Open source software, also known as free software, now offers a creative platform with world-class programs. Just ask the people who have completed high-quality projects or developed popular web 2.0 sites using open source desktop applications. This phenomenon is no longer underground or restricted to techies - there have been more than 61 million downloads of the Audacity audio editor and more than 60 million downloads of the GIMP for Windows photographic tool from SourceForge.net alone. Crafting Digital Media is your foundation course in photographic manipulation, illustration, animation, 3D

  5. A crafting of potentials

    DEFF Research Database (Denmark)

    Kilbourn, Kyle

    In the movement from understanding the past towards creating the future design anthropology, as a discipline, will turn from one with archival qualities to one endowed with potentials for change. One challenge facing design anthropology is how to show relevance for theory generation while also in......-as is complemented by designing for as design anthropologists stage design workshops, span knowledge traditions, and make design moves. Reflecting on my own research process, I trace a few research tools that underline the craft of design anthropology....

  6. Self-crafting vegetable snacks

    NARCIS (Netherlands)

    Raghoebar, Sanne; Kleef, van Ellen; Vet, de Emely

    2017-01-01

    Purpose: The purpose of this paper is to test whether the IKEA-effect (Norton et al., 2012) – better liking for self-crafted products than for identical products crafted by others – can be exploited to increase liking and consumption of vegetable snacks in children. Design/methodology/approach: A

  7. Study of quality of nine aluminium alloys surfaces created using abrasiv waterjet

    Czech Academy of Sciences Publication Activity Database

    Klichová, Dagmar; Klich, Jiří; Gurková, Lucie

    2016-01-01

    Roč. 2016, March 2016 (2016), s. 892-895 ISSN 1805-0476 R&D Projects: GA MŠk(CZ) LO1406; GA MŠk ED2.1.00/03.0082 Institutional support: RVO:68145535 Keywords : abrasive waterjet * aluminium alloy * optical profilometer Subject RIV: JQ - Machines ; Tools http://www.mmscience.eu/content/file/archives/MM_Science_201608.pdf

  8. Numerical simulation of internal flow in mixed-flow waterjet propulsion

    International Nuclear Information System (INIS)

    Wu, T T; Pan, Z Y; Zhang, D Q; Jia, Y Y

    2012-01-01

    In order to reveal the internal flow characteristic of a mixed-flow waterjet propulsion, a mixed-flow waterjet propulsion under different conditions was simulated based on multi-reference frame(MRF), the standard k − ε turbulent model and SIMPLEC algorithm. The relationship between pump performance instability and internal flow was obtained. The numerical results showed that characteristic instability occurred at 0.65-0.67Q BEP , the reason is that the backflow on the vaned diffuser hub-side blocks the downstream flow from the impeller. Therefore, the flow separates on the pressure surface of the impeller outlet and a strong vortex is generated, then the characteristic instability appeared due to the instability of internal flow. Backflow was found in diffuser passage at 0.65 Q BEP and 0.85 Q BEP , as flow rate decreases, the backflow region and velocity increases. Pressure fluctuation at diffuser inlet and diffuser passages was severe at at 0.65 Q BEP . According to the numerical simulation, the mixed-flow waterjet propulsion has characteristic instability at partial flow rate condition.

  9. 46 CFR 199.201 - Survival craft.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft. 199.201 Section 199.201 Shipping COAST... craft. (a) Each survival craft must be approved and equipped as follows: (1) Each lifeboat must be... addition to the survival craft required in paragraph (b)(1) of this section, additional liferafts must be...

  10. Perancangan Propeler Self-Propelled Barge

    Directory of Open Access Journals (Sweden)

    Billy Teguh kurniawan

    2013-03-01

    Full Text Available Makalah ini menyampaikan suatu penelitian tentang perancangan propeler yang optimal beserta pemilihan daya mesin yang efisien pada self-propelled barge dengan memperhitungkan besarnya nilai tahanan dari barge tersebut. Dengan penambahan sistem propulsi, diharapkan barge dapat beroperasi dengan lebih efisien dibandingkan saat barge beroperasi menggunakan sistem towing atau ditarik tug boat. Perhitungan tahanan barge dilakukan menggunakan metode Holtrop dan Guldhammer-Harvald sehingga dapat diperhi-tungkan geometri dan jenis propeler yang optimal beserta daya mesin yang efisien untuk barge. Propeler yang dianalisis adalah propeler tipe B-Troost Series, sedangkan variasi yang dilakukan untuk perencanaan propeler pada kajian ini adalah variasi putaran propeler pada rentang antara 310-800 rpm, serta variasi jumlah daun pada rentang tiga, empat, lima, dan enam. Besarnya nilai tahanan self-propelled barge untuk metode Holtrop adalah 105.91 kilonewton, sedangkan hasil per-hitungan dari metode Guldhammer-Harvald didapatkan nilai sebesar 109.14 kilonewton. Tipe propeler yang dipilih setelah dilakukan uji kavitasi adalah tipe Troost Series B4-40, dengan diameter sebesar 2.1 m, efisiensi sebesar 0.421, pitch ratio se-besar 0.591, dengan putaran propeler 400 rpm. Daya mesin yg dibutuhkan barge pada kondisi maksimum (BHPMCR sebesar 1669.5 HP. Dengan mempertimbangkan daya tersebut, maka dipilih mesin jenis Caterpillar tipe Marine 3516B yang mem-punyai daya maksimum sebesar 1285 kilowatt atau 1722.5 horsepower dengan putaran mesin sebesar 1200 rpm

  11. To craft or not to craft : The relationships between regulatory focus, job crafting and work outcomes

    NARCIS (Netherlands)

    Brenninkmeijer, Veerle; Hekkert-Koning, Marleen

    2015-01-01

    Purpose – The purpose of this paper is to examine relationships between regulatory focus, job crafting, work engagement and perceived employability. Regulatory focus theory distinguishes between promotion-focused individuals, who strive for growth and development, and preventionfocussed individuals,

  12. 32 CFR 700.406 - Naval Vessel Register, classification of naval craft, and status of ships and service craft.

    Science.gov (United States)

    2010-07-01

    ... craft, and status of ships and service craft. 700.406 Section 700.406 National Defense Department of... Register, classification of naval craft, and status of ships and service craft. (a) The Chief of Naval... craft and the designation of status for each ship and service craft. (b) Commissioned vessels and craft...

  13. Tomographic particle image velocimetry of a water-jet for low volume harvesting of fat tissue for regenerative medicine

    Directory of Open Access Journals (Sweden)

    Drobek Christoph

    2015-09-01

    Full Text Available Particle Image Velocimetry (PIV measurements of a water-jet for water-assisted liposuction (WAL are carried out to investigate the distribution of velocity and therefore momentum and acting force on the human sub-cutaneous fat tissue. These results shall validate CFD simulations and force sensor measurements of the water-jet and support the development of a new WAL device that is able to harvest low volumes of fat tissue for regenerative medicine even gentler than regular WAL devices.

  14. Evaluation of abrasive waterjet produced titan surfaces topography by spectral analysis techniques

    Directory of Open Access Journals (Sweden)

    D. Kozak

    2012-01-01

    Full Text Available Experimental study of a titan grade 2 surface topography prepared by abrasive waterjet cutting is performed using methods of the spectral analysis. Topographic data are acquired by means of the optical profilometr MicroProf®FRT. Estimation of the areal power spectral density of the studied surface is carried out using the periodogram method combined with the Welch´s method. Attention is paid to a structure of the areal power spectral density, which is characterized by means of the angular power spectral density. This structure of the areal spectral density is linked to the fine texture of the surface studied.

  15. Proposition of a Solution for the Setting of the Abrasive Waterjet Cutting Technology

    Czech Academy of Sciences Publication Activity Database

    Valíček, Jan; Harničárová, M.; Kušnerová, M.; Grznárik, R.; Zavadil, J.

    2013-01-01

    Roč. 13, č. 5 (2013), s. 279-285 ISSN 1335-8871 R&D Projects: GA MŠk ED2.1.00/03.0082 Institutional support: RVO:68145535 Keywords : abrasive waterjet cutting of materials * surface topography function * correlation relations * surface roughness * optimization of technology Subject RIV: JQ - Machines ; Tools Impact factor: 1.162, year: 2013 http://www.degruyter.com/view/j/msr.2013.13.issue-5/msr-2013-0041/msr-2013-0041. xml

  16. WATER-JET CUTTING MACHINE NOW AVAILABLE FROM THE CERN RAW MATERIALS STORES

    CERN Multimedia

    2007-01-01

    The CERN Raw Materials Stores has recently acquired a new water-jet cutting machine. The machine is capable of cutting all types and shapes of materials up to 70 mm in thickness, with an accuracy of +/- 0.1mm/m. For the time being, users requiring materials to be cut should supply drawings in DXF, DWG or IGES (AutoCad) file format. The machine will be operational as of 1st October 2007. The Stores Team Paulo Dos Santos FI-LS-MM 72308

  17. Tip-modified Propellers

    DEFF Research Database (Denmark)

    Andersen, Poul

    1999-01-01

    The paper deals with tip-modified propellers and the methods which, over a period of two decades, have been applied to develop such propellers. The development is driven by the urge to increase the efficiency of propellers and can be seen as analogous to fitting end plates and winglets to aircraft...... propeller, have efficiency increases of a reasonable magnitude in both open-water and behind-ship conditions....

  18. Experimental Study of the Ultrasonic Vibration-Assisted Abrasive Waterjet Micromachining the Quartz Glass

    Directory of Open Access Journals (Sweden)

    Rongguo Hou

    2018-01-01

    Full Text Available The ultrasonic vibration is used to enhance the capability of the abrasive water micromachining glass. And, the ultrasonic vibration is activated on the abrasive waterjet nozzle. The quality of the flow is improved, and the velocity of the abrasive is increased because of the addition of the ultrasonic energy. The relevant experimental results indicate that the erosion depth and the material volume removal of the glass are obviously increased when ultrasonic vibration is working. As for the influence of process parameters on the material removal of the glass such as vibration amplitude, system pressure, distance of the standoff, and abrasive size, the experimental results indicate that the system pressure and vibration contribute greatly to the glass material removal. Also, the erosion depth and the volume of material removal are increased with the increase in the vibration amplitude and system pressure. There are some uplifts found at the edge of erosion pit. Then, it can be inferred that the plastic method is an important material removal method during the machining process of ultrasonic vibration-assisted abrasive waterjet.

  19. Applicability of water-jet cutting technology to nuclear facility decommissioning

    International Nuclear Information System (INIS)

    Abe, Tadashi; Nisizaki, Tadashi; Matumura, Hiroyuki; Ikemoto, Yosikazu; Simizu, Hideki

    1991-01-01

    In nuclear facilities there exist, besides relatively simple components, such as vessels and piping, numerous complex components including the multilayered plate with water layer in between, a bunch of thin tubes and composite lamination of dissimilar materials like metal/non-metal. In conventional development of reactor dismantling technology, the technology development has been made mainly for remote cutting of thick-walled structures like the reactor pressure vessel and the reactor internals. These techniques, however, are not always suitable in cutting the above-mentioned structures. As means of cutting such structures efficiently, these is available the abrasion water-jet cutting technology. This technology is now drawing attention for cutting or shaping new materials like composite material and ceramics in high precision and high efficiency. In the present report by way of its feasibility in nuclear facilities decommissioning the following are described. Principle and features of the water-jet cutting technology, system con-figuration, cutting or shaping performance, and some examples of the cutting and shaping. (author)

  20. Fungal decay of traditional fishing craft

    Digital Repository Service at National Institute of Oceanography (India)

    Gupta, R.

    The artisanal fishermen land major portion of fish caught in India, employing traditional fishing craft and methods. These craft are built of indigenous wood and undergo rapid biodeterioration causing great economic loss. Soft-rot fungi...

  1. When Does Job Crafting Generalize To Home Crafting

    DEFF Research Database (Denmark)

    Demerouti, Evangelina; De Gieter, Sara; Haun, Verena

    Purpose: Job crafting represents attempts to expand (seeking resources or challenges) or reduce (reducing demands) the scope of the job such that it fits better to one’s preferences. The spillover hypothesis suggests that individuals generalize behaviors at work also to the non-work domain...

  2. Learning craft skills. Exploring preschoolers' craft making process

    Directory of Open Access Journals (Sweden)

    Virpi Yliverronen

    2016-06-01

    Full Text Available The aim of this study was to explore a preschooler craft-making process in which 18 preschool novices cut pieces for fabric bags and designed and printed patterns to decorate the bags. Through the task, children were familiarised with a small-scale holistic craft process. The intention was to determine how preschoolers perceived, verbalised and interpreted the craft-making process and how children used bodily expressions when explaining a learned craft skill. The present study relies on the videographic method: two preschool groups’ stamp printing activities were recorded, and each child was interviewed individually. Children’s embodied expressions were particularly in focus in video analysis. The results reveal that all the children were able to sufficiently explain the making phase, however, some children compensated for missing words using bodily and facial expressions and gestures when talking about making. The results showed that children worked logically, and the skill learning phases of perceiving, making, and interpretation were revealed from their learning.

  3. 46 CFR 199.261 - Survival craft.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft. 199.261 Section 199.261 Shipping COAST... SYSTEMS FOR CERTAIN INSPECTED VESSELS Additional Requirements for Cargo Vessels § 199.261 Survival craft. (a) Each survival craft must be approved and equipped as follows: (1) Each lifeboat must be a totally...

  4. 46 CFR 28.120 - Survival craft.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Survival craft. 28.120 Section 28.120 Shipping COAST... VESSELS Requirements for All Vessels § 28.120 Survival craft. (a) Except as provided in paragraphs (b) through (h) of this section and 28.305, each vessel must carry the survival craft specified in Table 28...

  5. 46 CFR 133.105 - Survival craft.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Survival craft. 133.105 Section 133.105 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS LIFESAVING SYSTEMS Requirements for All OSVs § 133.105 Survival craft. (a) Each survival craft must be approved and equipped as...

  6. Secondary School Design: Workshop Crafts.

    Science.gov (United States)

    Department of Education and Science, London (England).

    Design features are described for school shop facilities. Some general requirements common to most workshops are discussed; and specific design information is provided for general woodwork, general metalwork, and combined wood and metalwork facilities. The grouping of the workshop crafts and their relation to other parts of the school are also…

  7. CFD Based Erosion Modelling of Abrasive Waterjet Nozzle using Discrete Phase Method

    International Nuclear Information System (INIS)

    Kamarudin, Naqib Hakim; Prasada Rao, A K; Azhari, Azmir

    2016-01-01

    In Abrasive Waterjet (AWJ) machining, the nozzle is the most critical component that influences the performance, precision and economy. Exposure to a high speed jet and abrasives makes it susceptible to wear erosion which requires for frequent replacement. The present works attempts to simulate the erosion of the nozzle wall using computational fluid dynamics. The erosion rate of the nozzle was simulated under different operating conditions. The simulation was carried out in several steps which is flow modelling, particle tracking and erosion rate calculation. Discrete Phase Method (DPM) and K-ε turbulence model was used for the simulation. Result shows that different operating conditions affect the erosion rate as well as the flow interaction of water, air and abrasives. The simulation results correlates well with past work. (paper)

  8. Analysis of acoustic emission during abrasive waterjet machining of sheet metals

    Science.gov (United States)

    Mokhtar, Nazrin; Gebremariam, MA; Zohari, H.; Azhari, Azmir

    2018-04-01

    The present paper reports on the analysis of acoustic emission (AE) produced during abrasive waterjet (AWJ) machining process. This paper focuses on the relationship of AE and surface quality of sheet metals. The changes in acoustic emission signals recorded by the mean of power spectral density (PSD) via covariance method in relation to the surface quality of the cut are discussed. The test was made using two materials for comparison namely aluminium 6061 and stainless steel 304 with five different feed rates. The acoustic emission data were captured by Labview and later processed using MATLAB software. The results show that the AE spectrums correlated with different feed rates and surface qualities. It can be concluded that the AE is capable of monitoring the changes of feed rate and surface quality.

  9. Experimental research on the machinability of Hardox steel by abrasive waterjet cutting

    Directory of Open Access Journals (Sweden)

    Filip Alexandru Catalin

    2017-01-01

    Full Text Available One of the main present industry challenges is finding the most efficient manufacturing process for a certain part. When parts are made of strong steels like Hardox, their fabrication method is usually difficult. Abrasive waterjet cutting (AWJ is one of the cutting processes which can be used in this case. This paper presents an experimental research on the machinability of Hardox steel by AWJ. The experiments were conducted using a factorial design model considering two of the main influence parameters like the traverse speed and the distance between the nozzle and the surface of the material. Based on the measurement of the dimensions and the roughness of the parts, the influence of the parameters was revealed and analyzed. The manufacturing time was also compared, as it directly influences the production cost. Further research is considered to develop a mathematical model which can be used for a proper choice of the process parameters depending on the initial requirements.

  10. An experimental investigation on the pressure characteristics of high speed self-resonating pulsed waterjets influenced by feeding pipe diameter

    Energy Technology Data Exchange (ETDEWEB)

    Li, Dong; Kang, Dong; Ding, Xiao Long; Wang, Xiao Huan; Fang, Zhen Long [School of Power and Mechanical Engineering, Wuhan University, Hubei Province (China)

    2016-11-15

    The destructive power of a continuous waterjet issuing from a nozzle can be greatly enhanced by generating self-resonance in the nozzle assembly to produce a Self-resonating pulsed waterjet (SRPW). To further improve the performance of SRPW, effects of feeding pipe diameter on the pressure characteristics were experimentally investigated by measuring and analyzing the axial pressure oscillation peaks and amplitudes. Four organ-pipe nozzles of different chamber lengths and three feeding pipes of different diameters were employed. Results show that feeding pipe diameter cannot change the feature of SRPW of having an optimum standoff distance, but it slightly changes the oscillating frequency of the jet. It is also found that feeding pipe diameter significantly affects the magnitudes of pressure oscillation peak and amplitude, largely depending on the pump pressure and standoff distance. The enhancement or attenuation of the pressure oscillation peak and amplitude can be differently affected by the same feeding pipe diameter.

  11. 46 CFR 117.200 - Survival craft-general.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Survival craft-general. 117.200 Section 117.200 Shipping... Number and Type of Survival Craft § 117.200 Survival craft—general. (a) Each survival craft required on a... craft they replace. (c) A summary of survival craft requirements is provided in Table 117.200(c). Table...

  12. Experimental Investigation on the Influence of a Double-Walled Confined Width on the Velocity Field of a Submerged Waterjet

    Directory of Open Access Journals (Sweden)

    Xiaolong Ding

    2017-12-01

    Full Text Available The current research on confined submerged waterjets mainly focuses on the flow field of the impinging jet and wall jet. The double-sided wall vertically confined waterjet, which is widely used in many fields such as mining, cleaning and surface strengthening, has rarely been studied so far. In order to explore the influence of a double-sided wall confined width on the velocity field of submerged waterjet, an experiment was conducted with the application of 2D particle image velocimetry (PIV technology. The distribution of mean velocity and turbulent velocity in both horizontal and vertical planes was used to characterize the flow field under various confined widths. The results show that the vertical confinement has an obvious effect on the decay rate of the mean centerline velocity. When the confined width changes from 15 to 5, the velocity is reduced by 20%. In addition, with the decrease of the confined width, the jet has a tendency to spread horizontally. The vertically confined region induces a space hysteresis effect which changes the location of the transition region moving downstream. There are local negative pressure zones separating the fluid and the wall. This study of a double-walled confined jet provides some valuable information with respect to its mechanism and industrial application.

  13. Supporting Craft Sense in Early Education

    Directory of Open Access Journals (Sweden)

    Kalle Virta

    2013-10-01

    Full Text Available The research task was to describe and construct theoretical background for Craft Sense in early education. Craft Sense represents a learner’s skill for obtaining Sloyd (Craft, Design & Technology related knowledge, skills and understanding. The development of Craft Sense is based on producing artefacts and evaluating the production process. In this research, the concept of Craft Sense is based on the integration of Sloyd and meta-cognitive regulation of learning activities. Based on theoretical information, an empirical research question was formulated: “What kind of Craft Sense do children have in early education Sloyd?” The method of study was assessing picture supported learning on a Sloyd course for young children. The data was analyzed by qualitative content analysis and Child Behaviour Rating Scale (CBRS. Findings indicate that the development of children’s Craft Sense can be supported with pictures. Furthermore, the CBRS can be used to evaluate and understand children’s Craft Sense. Keywords: Craft Sense, Sloyd, Sloyd Education, Meta-cognition

  14. Research 2009-2011 - Digital Crafting

    DEFF Research Database (Denmark)

    Ramsgaard Thomsen, Mette; Tamke, Martin; Peder Pedersen, Claus

    2012-01-01

    The publication reports on the international research network 'Digital Crafting' organised in the period 2009-2011. The research network investigated profound changes in the design and building of architecture. Developing the term Digital Crafting, the network examined how the maturing of interfa......The publication reports on the international research network 'Digital Crafting' organised in the period 2009-2011. The research network investigated profound changes in the design and building of architecture. Developing the term Digital Crafting, the network examined how the maturing...

  15. The craft of scientific writing

    CERN Document Server

    Alley, Michael

    2019-01-01

    The Craft of Scientific Writing uses scores of examples to show the differences between scientific writing that informs and persuades and scientific writing that does not. Focusing on technical papers, dissertations, and reports, this text shows engineers, scientists, and technical professionals the five keys of style that distinguish the best scientific documents: (1) having the details presented in a methodical fashion, (2) having the important details emphasized, (3) having ideas cast into clear and precise sentences, (4) having clear connections between those ideas, and (5) having illustrations that persuade.

  16. Hydrodynamics of Ship Propellers

    DEFF Research Database (Denmark)

    Breslin, John P.; Andersen, Poul

    This book deals with flows over propellers operating behind ships, and the hydrodynamic forces and moments which the propeller generates on the shaft and on the ship hull.The first part of the text is devoted to fundamentals of the flow about hydrofoil sections (with and without cavitation...... of an intermittently cavitating propeller in a wake and the pressures and forces it exerts on the shaft and on the ship hull is examined. A final chapter discusses the optimization of efficiency of compound propulsors. The authors have taken care to clearly describe physical concepts and mathematical steps. Appendices...

  17. Crafting in context: Exploring when job crafting is dysfunctional for performance effectiveness.

    Science.gov (United States)

    Dierdorff, Erich C; Jensen, Jaclyn M

    2018-05-01

    Job crafting theory purports that the consequences of revising one's work role can be simultaneously beneficial and detrimental. Previous research, however, has almost exclusively emphasized the beneficial outcomes of job crafting. In the current study, we proposed dysfunctional consequences of crafting for performance-related outcomes in the form of a U-shaped relationship between job crafting and performance effectiveness (managerial ratings of job proficiency and peer ratings of citizenship behavior). We further predicted that elements of the task context (autonomy and ambiguity) and the social context (interdependence and social support) moderate these curvilinear relationships. Consistent with previous research, job crafting displayed positive and linear effects on work-related attitudes (job satisfaction and affective commitment). Consistent with our predictions, moderate levels of crafting were associated with dysfunctional performance-related outcomes and features of work context either exacerbated or dissipated these dysfunctional consequences of job crafting for individuals. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  18. Autonomous Propellant Loading Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The AES Autonomous Propellant Loading (APL) project consists of three activities. The first is to develop software that will automatically control loading of...

  19. Solid propellant impact tests

    International Nuclear Information System (INIS)

    Snow, E.C.

    1976-03-01

    Future space missions, as in the past, call for the continued use of radioisotopes as heat sources for thermoelectric power generators. In an effort to minimize the risk of radioactive contamination of the environment, a complete safety analysis of each such system is necessary. As a part of these analyses, the effects on such a system of a solid propellant fire environment resulting from a catastrophic launch pad abort must be considered. Several impact tests were conducted in which either a simulant MHW-FSA or a steel ball was dropped on the cold, unignited or the hot, burning surface of a block of UTP-3001 solid propellant. The rebound velocities were measured for both surface conditions of the propellant. The resulting coefficient of restitution, determined as the ratio of the components of the impact and rebound velocities perpendicular to the impact surface of the propellant, were not very dependent on whether the surface was cold or hot at the time of impact

  20. Modeling Propellant Tank Dynamics

    Data.gov (United States)

    National Aeronautics and Space Administration — The main objective of my work will be to develop accurate models of self-pressurizing propellant tanks for use in designing hybrid rockets. The first key goal is to...

  1. Disposal of Liquid Propellants

    Science.gov (United States)

    1990-03-13

    propellant includes an oxi- dizer (hydroxylammoniuin nitrate), a fuel (triethanolammonium nitrate), and water . In an- ticipation of widespread (both...are also included. 20. DISTRIBUTION/ AVAILABILIT ’." OF ABMTRACT 21 ABSTRACT SECURITY CLASSIF.CATICIN IUNCLASSIFIEDIUNLIMITED 0 SAME AS RPT. 0 OTIC...trieth- anolammoiur nitrate), anG water . In anticipation of widespread (both conti- nental U.S. and abroac) use of the propellant, USATHAMA began a

  2. Separation and reconstruction of high pressure water-jet reflective sound signal based on ICA

    Science.gov (United States)

    Yang, Hongtao; Sun, Yuling; Li, Meng; Zhang, Dongsu; Wu, Tianfeng

    2011-12-01

    The impact of high pressure water-jet on the different materials target will produce different reflective mixed sound. In order to reconstruct the reflective sound signals distribution on the linear detecting line accurately and to separate the environment noise effectively, the mixed sound signals acquired by linear mike array were processed by ICA. The basic principle of ICA and algorithm of FASTICA were described in detail. The emulation experiment was designed. The environment noise signal was simulated by using band-limited white noise and the reflective sound signal was simulated by using pulse signal. The reflective sound signal attenuation produced by the different distance transmission was simulated by weighting the sound signal with different contingencies. The mixed sound signals acquired by linear mike array were synthesized by using the above simulated signals and were whitened and separated by ICA. The final results verified that the environment noise separation and the reconstruction of the detecting-line sound distribution can be realized effectively.

  3. Nuclear thermal rockets using indigenous extraterrestrial propellants

    International Nuclear Information System (INIS)

    Zubrin, R.M.

    1990-01-01

    A preliminary examination of a concept for a Mars and outer solar system exploratory vehicle is presented. Propulsion is provided by utilizing a nuclear thermal reactor to heat a propellant volatile indigenous to the destination world to form a high thrust rocket exhaust. Candidate propellants, whose performance, materials compatibility, and ease of acquisition are examined and include carbon dioxide, water, methane, nitrogen, carbon monoxide, and argon. Ballistics and winged supersonic configurations are discussed. It is shown that the use of this method of propulsion potentially offers high payoff to a manned Mars mission. This is accomplished by sharply reducing the initial mission mass required in low earth orbit, and by providing Mars explorers with greatly enhanced mobility in traveling about the planet through the use of a vehicle that can refuel itself each time it lands. Thus, the nuclear landing craft is utilized in combination with a hydrogen-fueled nuclear-thermal interplanetary launch. By utilizing such a system in the outer solar system, a low level aerial reconnaissance of Titan combined with a multiple sample return from nearly every satellite of Saturn can be accomplished in a single launch of a Titan 4 or the Space Transportation System (STS). Similarly a multiple sample return from Callisto, Ganymede, and Europa can also be accomplished in one launch of a Titan 4 or the STS

  4. Crafting forgiveness accounts after war

    DEFF Research Database (Denmark)

    Meinert, Lotte; Obika, Julaina; Whyte, Susan Reynolds

    2014-01-01

    artist, the authors collected personal voice accounts of these ‘social repair’ processes and audio edited them in order to share them with a local public. The editing process raised critical issues regarding ‘editing for effect’, which are of wider relevance for discussions of ethnographic representation...... and social processes of editing past experience. As a way of crafting and controlling material, editing is always ‘for effect’. But the authors were struck by the powerful potentials of this artistic editing and by the difficulty in foreseeing or controlling its consequences among listeners. They suggest...... that personal processes of forgiveness resemble processes of editing, in the sense that past experience is revised and given narrative form, with an effect on the present and future of social relationships. When we edit, we foreground and background segments of data and experience, and cut parts of our...

  5. Trans-umbilical endoscopic cholecystectomy with a water-jet hybrid-knife: a pilot animal study.

    Science.gov (United States)

    Jiang, Sheng-Jun; Shi, Hong; Swar, Gyanendra; Wang, Hai-Xia; Liu, Xiao-Jing; Wang, Yong-Guang

    2013-10-28

    To investigate the feasibility and safety of Natural orifice trans-umbilical endoscopic cholecystectomy with a water-jet hybrid-knife in a non-survival porcine model. Pure natural orifice transluminal endoscopic surgery (NOTES) cholecystectomy was performed on three non-survival pigs, by transumbilical approach, using a water-jet hybrid-knife. Under general anesthesia, the following steps detailed the procedure: (1) incision of the umbilicus followed by the passage of a double-channel flexible endoscope through an overtube into the peritoneal cavity; (2) establishment of pneumoperitoneum; (3) abdominal exploration; (4) endoscopic cholecystectomy: dissection of the gallbladder performed using water jet equipment, ligation of the cystic artery and duct conducted using nylon loops; and (5) necropsy with macroscopic evaluation. Transumbilical endoscopic cholecystectomy was successfully completed in the first and third pig, with minor bleedings. The dissection times were 137 and 42 min, respectively. The total operation times were 167 and 69 min, respectively. And the lengths of resected specimen were 6.5 and 6.1 cm, respectively. Instillation of the fluid into the gallbladder bed produced edematous, distended tissue making separation safe and easy. Reliable ligation using double nylon loops insured the safety of cutting between the loops. There were no intraoperative complications or hemodynamic instability. Uncontrolled introperative bleeding occurred in the second case, leading to the operation failure. Pure NOTES trans-umbilical cholecystectomy with a water-jet hybrid-knife appears to be feasible and safe. Further investigation of this technique with long-term follow-up in animals is needed to confirm the preliminary observation.

  6. 46 CFR 117.130 - Stowage of survival craft.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Stowage of survival craft. 117.130 Section 117.130... AND ARRANGEMENTS Survival Craft Arrangements and Equipment § 117.130 Stowage of survival craft. (a) Each survival craft must be: (1) Secured to the vessel by a painter with a float-free link permanently...

  7. 46 CFR 133.130 - Stowage of survival craft.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Stowage of survival craft. 133.130 Section 133.130... SYSTEMS Requirements for All OSVs § 133.130 Stowage of survival craft. (a) General. Each survival craft must be stowed as follows: (1) Each survival craft must be as close to the accommodation and service...

  8. 46 CFR 180.175 - Survival craft equipment.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft equipment. 180.175 Section 180.175... TONS) LIFESAVING EQUIPMENT AND ARRANGEMENTS Survival Craft Arrangements and Equipment § 180.175 Survival craft equipment. (a) General. Each item of survival craft equipment must be of good quality, and...

  9. 46 CFR 199.130 - Stowage of survival craft.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Stowage of survival craft. 199.130 Section 199.130... craft. (a) General. Each survival craft must be stowed— (1) As close to the accommodation and service spaces as possible; (2) So that neither the survival craft nor its stowage arrangements will interfere...

  10. 46 CFR 117.175 - Survival craft equipment.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Survival craft equipment. 117.175 Section 117.175... AND ARRANGEMENTS Survival Craft Arrangements and Equipment § 117.175 Survival craft equipment. (a) General. Each item of survival craft equipment must be of good quality, and efficient for the purpose it...

  11. 46 CFR 117.150 - Survival craft embarkation arrangements.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Survival craft embarkation arrangements. 117.150 Section... EQUIPMENT AND ARRANGEMENTS Survival Craft Arrangements and Equipment § 117.150 Survival craft embarkation... apparatus when either— (1) The embarkation station for the survival craft is on a deck more than 4.5 meters...

  12. 46 CFR 180.130 - Stowage of survival craft.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Stowage of survival craft. 180.130 Section 180.130... TONS) LIFESAVING EQUIPMENT AND ARRANGEMENTS Survival Craft Arrangements and Equipment § 180.130 Stowage of survival craft. (a) Each survival craft must be: (1) Secured to the vessel by a painter with a...

  13. 46 CFR 28.310 - Launching of survival craft.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Launching of survival craft. 28.310 Section 28.310... Operate With More Than 16 Individuals on Board § 28.310 Launching of survival craft. A gate or other... each survival craft which weighs more than 110 pounds (489 Newtons), to allow the survival craft to be...

  14. Propellers in Saturn's rings

    Science.gov (United States)

    Sremcevic, M.; Stewart, G. R.; Albers, N.; Esposito, L. W.

    2013-12-01

    Theoretical studies and simulations have demonstrated the effects caused by objects embedded in planetary rings. Even if the objects are too small to be directly observed, each creates a much larger gravitational imprint on the surrounding ring material. These strongly depend on the mass of the object and range from "S" like propeller-shaped structures for about 100m-sized icy bodies to the opening of circumferential gaps as in the case of the embedded moons Pan and Daphnis and their corresponding Encke and Keeler Gaps. Since the beginning of the Cassini mission many of these smaller objects (~data from Cassini Ultraviolet Imaging Spectrograph (UVIS) and Imaging Science Subsystem (ISS) experiments. We show evidence that B ring seems to harbor two distinct populations of propellers: "big" propellers covering tens of degrees in azimuth situated in the densest part of B ring, and "small" propellers in less dense inner B ring that are similar in size and shape to known A ring propellers. The population of "big" propellers is exemplified with a single object which is observed for 5 years of Cassini data. The object is seen as a very elongated bright stripe (40 degrees wide) in unlit Cassini images, and dark stripe in lit geometries. In total we report observing the feature in images at 18 different epochs between 2005 and 2010. In UVIS occultations we observe this feature as an optical depth depletion in 14 out of 93 occultation cuts at corrotating longitudes compatible with imaging data. Combining the available Cassini data we infer that the object is a partial gap located at r=112,921km embedded in the high optical depth region of the B ring. The gap moves at Kepler speed appropriate for its radial location. Radial offsets of the gap locations in UVIS occultations are consistent with an asymmetric propeller shape. The asymmetry of the observed shape is most likely a consequence of the strong surface mass density gradient, as the feature is located at an edge between

  15. DEVELOPMENT OF INTERACTIVE MULTIMEDIA COURSEWARE (E-CRAFT FOR CRAFT EDUCATION

    Directory of Open Access Journals (Sweden)

    Salyani OSMAN,

    2012-08-01

    Full Text Available The way of teaching and learning traditional crafts have always used traditional apprenticeship learning methods where the expert facilitates transfer of practice skill sets to novices. As a craft has been taught in conventional approach, the students and experts have been facing several problems especially when expert needs to teach a group of students. An appropriate mapping of craft education and Information and Communication Technologies using Multimedia technology for instance, has the potential in transforming traditional craft learning into more flexible environment. This paper reports on a research project on development of an interactive multimedia courseware package for teaching and learning traditional craft called e-CRAFT. The e-CRAFT is specially designed for songket weaving course taught to certificate and diploma students from Fakulti Seni Kraf Tenunan in their first year study at Institut Kraf Negara, Malaysia (National Craft Institute. The courseware was developed in a web-based environment and overall development process was based on the Dick and Carey's process model and conceptual Instructional Design framework. It is made up of eight learning modules: Introduction, Materials & Tools, Knowing Motifs, Learn How to Weave, Quizzes & Test, Online Discussion, Glossary and Help module. In order to test whether the courseware is suitable in terms of usability, pilot testing was done to a sample of 10 students. The results from pilot test received positive feedback which signifies the courseware is considered acceptable for effectiveness study and help for further improve of the e-CRAFT courseware.

  16. Modern electrical installation for craft students

    CERN Document Server

    Scaddan, Brian

    2013-01-01

    Modern Electrical Installation for Craft Students, Volume 2, Third Edition discusses several topics concerning electrical installations. The book is comprised of eight chapters that deal with craft theory, associated subjects, and electrical industries. Chapter 1 covers inductors and inductance, while Chapter 2 tackles capacitors and capacitance. Chapter 3 deals with inductance and capacitance in installation work. The book also discusses cells, batteries, and transformers. The electrical industries, control and earthing, and testing are also dealt with. The last chapter discusses the basic el

  17. Technology of foamed propellants

    Energy Technology Data Exchange (ETDEWEB)

    Boehnlein-Mauss, Jutta; Kroeber, Hartmut [Fraunhofer Institut fuer Chemische Technologie ICT, Pfinztal (Germany)

    2009-06-15

    Foamed propellants are based on crystalline explosives bonded in energetic reaction polymers. Due to their porous structures they are distinguished by high burning rates. Energy content and material characteristics can be varied by using different energetic fillers, energetic polymers and porous structures. Foamed charges can be produced easily by the reaction injection moulding process. For the manufacturing of foamed propellants a semi-continuous remote controlled production plant in pilot scale was set up and a modified reaction injection moulding process was applied. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  18. Employees’ Perceived Opportunities to Craft and In-Role Performance: The Mediating Role of Job Crafting and Work Engagement

    Science.gov (United States)

    van Wingerden, Jessica; Poell, Rob F.

    2017-01-01

    The present study was designed to gain knowledge of the relationship between employees’ perceived opportunities to craft, their actual job crafting behavior and, in line with JD-R theory, subsequently their work engagement and performance. Although scholars have suggested that employees’ perceived opportunities to craft their job may predict their actual job crafting behavior, which may have consequences for their well-being and performance, no study has examined the relationships between these variables. We collected data among a heterogeneous group of Dutch employees (N = 2090). Participants of the study reported their perceived opportunities to craft, job crafting behavior, work engagement and performance. Results indicated that individuals who experience a high level of opportunities to craft reported higher levels of job crafting behavior. In turn, perceived opportunities to craft and job crafting behavior related to higher levels of work engagement and subsequently performance. We discuss the implications of these findings for theory and practice. PMID:29118729

  19. Employees' Perceived Opportunities to Craft and In-Role Performance: The Mediating Role of Job Crafting and Work Engagement.

    Science.gov (United States)

    van Wingerden, Jessica; Poell, Rob F

    2017-01-01

    The present study was designed to gain knowledge of the relationship between employees' perceived opportunities to craft, their actual job crafting behavior and, in line with JD-R theory, subsequently their work engagement and performance. Although scholars have suggested that employees' perceived opportunities to craft their job may predict their actual job crafting behavior, which may have consequences for their well-being and performance, no study has examined the relationships between these variables. We collected data among a heterogeneous group of Dutch employees ( N = 2090). Participants of the study reported their perceived opportunities to craft, job crafting behavior, work engagement and performance. Results indicated that individuals who experience a high level of opportunities to craft reported higher levels of job crafting behavior. In turn, perceived opportunities to craft and job crafting behavior related to higher levels of work engagement and subsequently performance. We discuss the implications of these findings for theory and practice.

  20. Effect of Abrasive Waterjet Peening Surface Treatment of Steel Plates on the Strength of Single-Lap Adhesive Joints

    Directory of Open Access Journals (Sweden)

    Kamil Anasiewicz

    2017-09-01

    Full Text Available The paper presents results of comparative study of shear strength of single–lap adhesive joints, depending on the method of surface preparation of steel plates with increased corrosion resistance. The method of preparing adherend surfaces is often one of the most important factors determining the strength of adhesive joints. Appropriate geometric surface development and cleaning of the surface enhances adhesion forces between adherend material and adhesive. One of the methods of shaping engineering materials is waterjet cutting, which in the AWJP – abrasive waterjet peening variant, serves to shape flat surfaces of the material by changing the roughness and introducing stresses into the surface layer. These changes are valuable when preparing adhesive joints. In the study, surface roughness parameters obtained with AWJP treatment, were analyzed in direct relation to the strength of the adhesive joint. As a consequence of the experimental results analysis, the increase in the strength of the adhesive joints was observed in a certain range of parameters used for AWJP treatment. A decrease in shear strength of adhesive joint with the most modified topography of overlap surface was observed.

  1. Propeller TAP flap

    DEFF Research Database (Denmark)

    Thomsen, Jørn Bo; Bille, Camilla; Wamberg, Peter

    2013-01-01

    major complications needing additional surgery. One flap was lost due to a vascular problem. Breast reconstruction can be performed by a propeller TAP flap without cutting the descending branch of the thoracodorsal vessels. However, the authors would recommend that a small cuff of muscle is left around...

  2. New Propellants and Cryofuels

    Science.gov (United States)

    Palasezski, Bryan; Sullivan, Neil S.; Hamida, Jaha; Kokshenev, V.

    2006-01-01

    The proposed research will investigate the stability and cryogenic properties of solid propellants that are critical to NASA s goal of realizing practical propellant designs for future spacecraft. We will determine the stability and thermal properties of a solid hydrogen-liquid helium stabilizer in a laboratory environment in order to design a practical propellant. In particular, we will explore methods of embedding atomic species and metallic nano-particulates in hydrogen matrices suspended in liquid helium. We will also measure the characteristic lifetimes and diffusion of atomic species in these candidate cryofuels. The most promising large-scale advance in rocket propulsion is the use of atomic propellants; most notably atomic hydrogen stabilized in cryogenic environments, and metallized-gelled liquid hydrogen (MGH) or densified gelled hydrogen (DGH). The new propellants offer very significant improvements over classic liquid oxygen/hydrogen fuels because of two factors: (1) the high energy-release, and (ii) the density increase per unit energy release. These two changes can lead to significant reduced mission costs and increased payload to orbit weight ratios. An achievable 5 to 10 percent improvement in specific impulse for the atomic propellants or MGH fuels can result in a doubling or tripling of system payloads. The high-energy atomic propellants must be stored in a stabilizing medium such as solid hydrogen to inhibit or delay their recombination into molecules. The goal of the proposed research is to determine the stability and thermal properties of the solid hydrogen-liquid helium stabilizer. Magnetic resonance techniques will be used to measure the thermal lifetimes and the diffusive motions of atomic species stored in solid hydrogen grains. The properties of metallic nano-particulates embedded in hydrogen matrices will also be studied and analyzed. Dynamic polarization techniques will be developed to enhance signal/noise ratios in order to be able to

  3. Development of Interactive Multimedia Courseware (e-CRAFT) for Craft Education

    Science.gov (United States)

    Osman, Salyani; Sahari, Noraidah; Zin, Nor Azan Mat

    2012-01-01

    The way of teaching and learning traditional crafts have always used traditional apprenticeship learning methods where the expert facilitates transfer of practice skill sets to novices. As a craft has been taught in conventional approach, the students and experts have been facing several problems especially when expert needs to teach a group of…

  4. Prediction of Cavitating Waterjet Propulsor Performance Using a Boundary Element Method

    Science.gov (United States)

    2007-10-01

    addressed. Instead, the Young, Y.L., Numerical Modeling of Supercavitating round trailing edge is modified to be a sharp one by and Surface-Piercing... Supercavitating Propeller Flows," Journal of Ship circulation distribution, and thus on the predicted thrust Research, Vol. 47, pp. 48-62, March 2003. and

  5. The craft of intensive care medicine.

    Science.gov (United States)

    Carmel, Simon

    2013-06-01

    The practice of medicine is often represented as a dualism: is medicine a 'science' or an 'art'? This dualism has been long-lasting, with evident appeal for the medical profession. It also appears to have been rhetorically powerful, for example in enabling clinicians to resist the encroachment of 'scientific' evidence-based medicine into core areas of medical work such as individual clinical judgement. In this article I want to make the case for a more valid conceptualisation of medical practice: that it is a 'craft' activity. The case I make is founded on a theoretical synthesis of the concept of craft, combined with an analysis of ethnographic observations of routine medical practice in intensive care. For this context the craft aspects of medical work can be seen in how biomedical and other types of knowledge are used in practice, the embodied skills and practical judgement of practitioners and the technological and material environment. These aspects are brought together in two conceptual dimensions for 'craft': first, the application of knowledge; second, interaction with the material world. Some practical and political implications of a 'craft' metaphor for medical practice are noted. © 2013 The Author. Sociology of Health & Illness © 2013 Foundation for the Sociology of Health & Illness/John Wiley & Sons Ltd.

  6. The screw propeller

    Science.gov (United States)

    Larrabee, E. E.

    1980-07-01

    Marine and air screw propellers are considered in terms of theoretical hydrodynamics as developed by Joukowsky, Prandtl, and Betz. Attention is given to the flow around wings of finite span where spanwise flow exists and where lift and the bound vorticity must all go smoothly to zero at the wing tips. The concept of a trailing vortex sheet made up of infinitesimal line vortexes roughly aligned with the direction of flight is discussed in this regard. Also considered is induced velocity, which tends to convect the sheet downward at every stage in the roll-up process, the vortex theory of propellers and the Betz-Prandtl circulation distribution. The performance of the Gossamer Albatross and of a pedal-driven biplane called the Chrysalis are also discussed.

  7. From Gender-segregated Subjects to Multi-material Craft: Craft Student Teachers’Views on the Future of the Craft Subject

    Directory of Open Access Journals (Sweden)

    Jaana Lepistö

    2015-12-01

    Full Text Available This paper describes the views of student teachers of craft about the future of craft as a school subject. The study was conducted at the University of Turku, Department of Teacher Education, in Rauma in 2014. The literature review revealed that the subject of craft in Finnish basic education is understood as a dialog between the maker and the materials. However, teaching and learning craft in schools and in teacher education has a strong gender-based tradition. The aim of this study is to investigate student teachers’ understanding of craft as a school subject in the future and their solutions to teaching craft in basic education. The data were collected from essays (N = 20 written by student teachers of craft. The essays were analyzed qualitatively using content analysis. The results showed that the student teachers of craft viewed holistic craft, reflective action readiness, entrepreneurial behaviour, multiple skills, the use of versatile materials, and craft as sources of pleasure and the main solutions for the future of craft as a subject.

  8. Automatic Construction by Contour Crafting Technology

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Khorramshahi

    2017-07-01

    Full Text Available Contour Crafting is a novel technology in construction industry based on 3D printing that uses robotics to construct free form building structures by repeatedly laying down layers of material such as concrete. It is actually an approach to scale up automatic fabrication from building small industrial parts to constructing buildings. However, there are little information about contour crafting (CC in current use; present paper aims to describe the operational steps of creating a whole building by the machine reviewing relevant literature. Furthermore, it will represent the advantages of CC usage compared to traditional construction methods, as well as its applicability in construction industry.

  9. Crafting by concepts fiber arts and mathematics

    CERN Document Server

    Belcastro, Sarah-Marie

    2016-01-01

    From the editors of the popular Making Mathematics with Needlework, this book presents projects that highlight the relationship between types of needlework and mathematics. Chapters start with accessible overviews presenting the interplay between mathematical concepts and craft expressions. Following sections explain the mathematics in more detail, and provide suggestions for classroom activities. Each chapter ends with specific crafting instructions. Types of needlework included are knitting, crochet, needlepoint, cross-stitch, quilting, temari balls, beading, tatting, and string art. Instructions are written as ordinary patterns, so the formatting and language will be familiar to crafters.

  10. Friedel-Crafts Acylation with Amides

    Science.gov (United States)

    Raja, Erum K.; DeSchepper, Daniel J.; Nilsson Lill, Sten O.; Klumpp, Douglas A.

    2012-01-01

    Friedel-Crafts acylation has been known since the 1870s and it is an important organic synthetic reaction leading to aromatic ketone products. Friedel-Crafts acylation is usually done with carboxylic acid chlorides or anhydrides while amides are generally not useful substrates in these reactions. Despite being the least reactive carboxylic acid derivative, we have found a series of amides capable of providing aromatic ketones in good yields (55–96%, 17 examples). We propose a mechanism involving diminished C-N resonance through superelectrophilic activation and subsequent cleavage to acyl cations. PMID:22690740

  11. 46 CFR 199.230 - Stowage of survival craft.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Stowage of survival craft. 199.230 Section 199.230... Stowage of survival craft. (a) To meet the requirements of § 199.130(b)(1), each lifeboat on a passenger... height of a survival craft must take into account the vessel's escape provisions, the vessel's size, and...

  12. 46 CFR 180.200 - Survival craft-general.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft-general. 180.200 Section 180.200 Shipping...) LIFESAVING EQUIPMENT AND ARRANGEMENTS Number and Type of Survival Craft § 180.200 Survival craft—general. (a) Each survival craft required on a vessel by this part must meet one of the following: (1) For an...

  13. 46 CFR 180.150 - Survival craft embarkation arrangements.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft embarkation arrangements. 180.150 Section... (UNDER 100 GROSS TONS) LIFESAVING EQUIPMENT AND ARRANGEMENTS Survival Craft Arrangements and Equipment § 180.150 Survival craft embarkation arrangements. (a) A launching appliance approved under approval...

  14. 47 CFR 97.215 - Telecommand of model craft.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Telecommand of model craft. 97.215 Section 97... AMATEUR RADIO SERVICE Special Operations § 97.215 Telecommand of model craft. An amateur station transmitting signals to control a model craft may be operated as follows: (a) The station identification...

  15. 75 FR 50773 - Invocation of Sunken Military Craft Act

    Science.gov (United States)

    2010-08-17

    ... Military Craft Act AGENCY: Coast Guard, DHS. ACTION: Notice. SUMMARY: The Coast Guard is announcing that a C-130 aircraft which crashed off the coast of California is a sunken military craft. It is therefore... is announcing that the wreckage of CG 1705 is a sunken military craft, and is therefore protected...

  16. 46 CFR 108.530 - Stowage of survival craft.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Stowage of survival craft. 108.530 Section 108.530... AND EQUIPMENT Lifesaving Equipment § 108.530 Stowage of survival craft. (a) General. Each survival craft required to be served by a launching appliance or marine evacuation system must be stowed as...

  17. 46 CFR 199.290 - Stowage of survival craft.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Stowage of survival craft. 199.290 Section 199.290... of survival craft. (a) To meet the requirements of § 199.130(b)(1), each lifeboat— (1) On a cargo... required under § 199.261(e), no stowage position or muster and embarkation station for a survival craft on...

  18. 46 CFR 122.518 - Inflatable survival craft placards.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Inflatable survival craft placards. 122.518 Section 122... Preparations for Emergencies § 122.518 Inflatable survival craft placards. (a) Every vessel equipped with an inflatable survival craft must have approved placards or other cards containing instructions for launching...

  19. 32 CFR 700.872 - Ships and craft in drydock.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 5 2010-07-01 2010-07-01 false Ships and craft in drydock. 700.872 Section 700... Special Circumstances/ships in Naval Stations and Shipyards § 700.872 Ships and craft in drydock. (a) The... ship or craft, not in commission, is in a naval drydock, the provisions of this article shall apply...

  20. 33 CFR 401.58 - Pleasure craft scheduling.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Pleasure craft scheduling. 401.58... OF TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Seaway Navigation § 401.58 Pleasure craft scheduling. (a) The transit of pleasure craft shall be scheduled by the traffic controller or the officer in...

  1. 29 CFR 1202.8 - Hearings on craft or class.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 4 2010-07-01 2010-07-01 false Hearings on craft or class. 1202.8 Section 1202.8 Labor... craft or class. In the event the contesting parties or organizations are unable to agree on the..., specifying the craft or class of employees eligible to participate in the designation of representatives. ...

  2. 46 CFR 108.525 - Survival craft number and arrangement.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Survival craft number and arrangement. 108.525 Section... UNITS DESIGN AND EQUIPMENT Lifesaving Equipment § 108.525 Survival craft number and arrangement. (a... arrangement of survival craft: (1) Lifeboats with an aggregate capacity to accommodate the total number of...

  3. 46 CFR 185.518 - Inflatable survival craft placards.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Inflatable survival craft placards. 185.518 Section 185... 100 GROSS TONS) OPERATIONS Preparations for Emergencies § 185.518 Inflatable survival craft placards. (a) Every vessel equipped with an inflatable survival craft must have approved placards or other...

  4. 46 CFR 28.125 - Stowage of survival craft.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Stowage of survival craft. 28.125 Section 28.125... FISHING INDUSTRY VESSELS Requirements for All Vessels § 28.125 Stowage of survival craft. (a) Each..., inflatable buoyant apparatus, and any auxiliary craft used in their place, must be kept readily accessible...

  5. 46 CFR 28.130 - Survival craft equipment.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Survival craft equipment. 28.130 Section 28.130 Shipping... INDUSTRY VESSELS Requirements for All Vessels § 28.130 Survival craft equipment. (a) General. Each item of survival craft equipment must be of good quality, effective for the purpose it is intended to serve, and...

  6. 47 CFR 80.1095 - Survival craft equipment.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Survival craft equipment. 80.1095 Section 80... for Ship Stations § 80.1095 Survival craft equipment. (a) At least three two-way VHF radiotelephone... they can be rapidly placed in any survival craft other than life rafts required by Regulation III/26.1...

  7. 46 CFR 28.805 - Launching of survival craft.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Launching of survival craft. 28.805 Section 28.805... FISHING INDUSTRY VESSELS Aleutian Trade Act Vessels § 28.805 Launching of survival craft. In addition to the survival craft requirements in subpart B, each vessel must have a gate or other opening in the...

  8. The Art and Craft of Science

    Science.gov (United States)

    Root-Bernstein, Robert; Root-Bernstein, Michele

    2013-01-01

    Walter Alvarez, a doctor and physiologist of some renown, decided to send his scientifically talented son, Luis, to an arts and crafts school where Luis took industrial drawing and woodworking instead of calculus. Luis Alvarez won the Nobel Prize in physics in 1968. Einstein was certainly not a standout in his mathematics and physics classes. Yet…

  9. Craft Knowledge: Of Disciplinarity in Writing Studies

    Science.gov (United States)

    Johnson, Robert R.

    2010-01-01

    This article argues that craft knowledge can provide a disciplinary rationale for writing studies. It draws from the ancient concepts of teche, phronesis, and the four causes of making and makes the case for a definition of disciplinary knowledge fitting for writing studies. The article concludes with a conceptual framework that can serve as a…

  10. Rationalizing Cooperation: Moroccan Craft, Politics, and Education

    Science.gov (United States)

    Nicholas, Claire

    2018-01-01

    State attempts to rationalize Moroccan craft education reflect the ambivalent status of traditional knowledge in a modern economy. Female artisans, recently organized as a cooperative, navigate this ambivalence in a weaving "theory" class and in their "occupation" of the cooperative structure itself. During performances of…

  11. The nature of creativity in craft

    DEFF Research Database (Denmark)

    Glaveanu, Vlad Petre

    2012-01-01

    The present article explores the nature of creativity in craft and does so with the help of a case study of traditional Easter egg decoration. It starts by positioning the domain of folk art in relation to fine art and within a larger category of everyday life forms of creative expression...

  12. Antecedents of daily team job crafting

    NARCIS (Netherlands)

    Mäkikangas, Anne; Bakker, Arnold B.; Schaufeli, Wilmar B.

    2017-01-01

    This study investigated potential antecedents of team job crafting defined as the extent to which team members engage together in increasing (social and structural) job resources and challenges, and decreasing hindering job demands. Mindful of the teamwork literature, we hypothesized that individual

  13. Meaningful work and work engagement : The mediating role of perceived opportunity to craft and job crafting behavior

    NARCIS (Netherlands)

    Van Wingerden, Jessica; van der Stoep, Joost; Poell, R.F.

    2018-01-01

    This study examines the impact of meaningful work on employees’ level of work engagement as mediated by perceived opportunities to craft and job crafting. Based on the literature on meaningful work and job crafting, we hypothesize that meaningful work has a positive relationship with an employee’s

  14. Testing of Alternative Abrasives for Water-Jet Cutting at C Tank Farm

    Energy Technology Data Exchange (ETDEWEB)

    Krogstad, Eirik J.

    2013-08-01

    Legacy waste from defense-related activities at the Hanford Site has predominantly been stored in underground tanks, some of which have leaked; others may be at risk to do so. The U.S. Department of Energy’s goal is to empty the tanks and transform their contents into more stable waste forms. To do so requires breaking up, and creating a slurry from, solid wastes in the bottoms of the tanks. A technology developed for this purpose is the Mobile Arm Retrieval System. This system is being used at some of the older single shell tanks at C tank farm. As originally planned, access ports for the Mobile Arm Retrieval System were to be cut using a high- pressure water-jet cutter. However, water alone was found to be insufficient to allow effective cutting of the steel-reinforced tank lids, especially when cutting the steel reinforcing bar (“rebar”). The abrasive added in cutting the hole in Tank C-107 was garnet, a complex natural aluminosilicate. The hardness of garnet (Mohs hardness ranging from H 6.5 to 7.5) exceeds that of solids currently in the tanks, and was regarded to be a threat to Hanford Waste Treatment and Immobilization Plant systems. Olivine, an iron-magnesium silicate that is nearly as hard as garnet (H 6.5 to 7), has been proposed as an alternative to garnet. Pacific Northwest National Laboratory proposed to test pyrite (FeS2), whose hardness is slightly less (H 6 to 6.5) for 1) cutting effectiveness, and 2) propensity to dissolve (or disintegrate by chemical reaction) in chemical conditions similar to those of tank waste solutions. Cutting experiments were conducted using an air abrader system and a National Institute of Standards and Technology Standard Reference Material (SRM 1767 Low Alloy Steel), which was used as a surrogate for rebar. The cutting efficacy of pyrite was compared with that of garnet and olivine in identical size fractions. Garnet was found to be most effective in removing steel from the target; olivine and pyrite were less

  15. Strength of Screw Propellers

    Science.gov (United States)

    1975-07-07

    ship because of increese of propeller efficiency and saving on the high cost of difficult to obtain materials (bronze, brass, stainless steel). The...indAjate that. x :axmuin stresses in the blade cross section are the cor-,prc-.,; ivFe norm-al strcs3es at point G. The maximom tensile stres-ses cis a...and stern part of the ship. Because of purely technical difficulties and also because of the relatively high cost of preparations for such tests, only

  16. Surface integrity in tangential turning of hybrid MMC A359/B4C/Al2O3by abrasive waterjet

    Czech Academy of Sciences Publication Activity Database

    Srivastava, A. K.; Naga, A.; Dixita, A. R.; Tiwaric, S.; Ščučka, Jiří; Zeleňák, Michal; Hloch, Sergej; Hlaváček, Petr

    2017-01-01

    Roč. 28, č. 28 (2017), s. 11-20 ISSN 1526-6125 R&D Projects: GA MŠk(CZ) LO1406; GA MŠk ED2.1.00/03.0082 Institutional support: RVO:68145535 Keywords : metal matrix composite * abrasive waterjet turning * surface topography * surface roughness * residual stresses Subject RIV: JQ - Machines ; Tools OBOR OECD: Mechanical engineering Impact factor: 2.322, year: 2016 http://www.sciencedirect.com/science/article/pii/S1526612517301287

  17. From Gender-segregated Subjects to Multi-material Craft: Craft Student Teachers’Views on the Future of the Craft Subject

    OpenAIRE

    Jaana Lepistö; Eila Lindfors

    2015-01-01

    This paper describes the views of student teachers of craft about the future of craft as a school subject. The study was conducted at the University of Turku, Department of Teacher Education, in Rauma in 2014. The literature review revealed that the subject of craft in Finnish basic education is understood as a dialog between the maker and the materials. However, teaching and learning craft in schools and in teacher education has a strong gender-based tradition. The aim of this study is to in...

  18. Research on and Design of a Self-Propelled Nozzle for the Tree-Type Drilling Technique in Underground Coal Mines

    Directory of Open Access Journals (Sweden)

    Yiyu Lu

    2015-12-01

    Full Text Available Due to the increasing depths of coal mines and the low permeability of some coal seams, conventional methods of gas drainage in underground mines are facing many problems. To improve gas extraction, a new technique using water jets to drill tree-type boreholes in coal seams is proposed. A self-propelled water-jet drilling nozzle was designed to drill these boreholes. The configuration of the self-propelled nozzle was optimized by conducting drilling experiments and self-propelling force measurements. Experimental results show that the optimal self-propelled nozzle has a forward orifice axial angle at 25°, a radial angle at 90°, a center distance of 1.5 mm, and backward pointing orifices with an axial angle of 25°. The self-propelling force generated by the jets of the nozzle with 30 MPa pump pressure can reach 29.8 N, enough to pull the hose and the nozzle forward without any external forces. The nozzle can drill at speeds up to 41.5 m/h with pump pressures at 30 MPa. The radial angles of the forward orifices improve the rock breaking performance of the nozzle and, with the correct angle, the rock breaking area of the orifices overlap to produce a connecting hole. The diameter of boreholes drilled by this nozzle can reach 35.2 mm. The nozzle design can be used as the basis for designing other self-propelled nozzles. The drilling experiments demonstrate the feasibility of using the tree-type drilling technique in underground mines.

  19. An improved approach to exchange non-rectangular departments in CRAFT algorithm

    OpenAIRE

    Esmaeili Aliabadi, Danial; Pourghannad, Behrooz

    2012-01-01

    In this Paper, an algorithm which improves CRAFT algorithm’s efficacy is developed. CRAFT is an algorithm widely used to solve facility layout problems. Our proposed method, named Plasma, can be used to improve CRAFT results. In this note, Plasma algorithm is tested in several sample problems. The comparison between Plasma and classic CRAFT and also Micro-CRAFT indicates that Plasma is successful in cost reduction in comparison with CRAFT and Micro-CRAFT.

  20. Sustainable Innovation of Glass Design and Craft

    DEFF Research Database (Denmark)

    Sparre-Petersen, Maria

    2014-01-01

    Barely any research has been made into the implementation of sustainable principles in glass design and craft. A common tendency among students and practitioners is to consider it problematic if not impossible to develop a “truly sustainable practice”. Generally glass crafts people and glass...... designers aim to explore new aesthetic possibilities for the material and see sustainability as a hindrance for aesthetic freedom. On the contrary the field of design has strong and growing emphasis on sustainable development. Fry (2009) argues that what he defines as sustain-ability is not an end goal...... but an ongoing process of re-directing the way we design our world and thereby our future. This approach along with further research into sustainable development within the field of design and combined with material specific methodologies may reveal new possibilities for sustainable as well as aesthetic...

  1. Concept annotation in the CRAFT corpus.

    Science.gov (United States)

    Bada, Michael; Eckert, Miriam; Evans, Donald; Garcia, Kristin; Shipley, Krista; Sitnikov, Dmitry; Baumgartner, William A; Cohen, K Bretonnel; Verspoor, Karin; Blake, Judith A; Hunter, Lawrence E

    2012-07-09

    Manually annotated corpora are critical for the training and evaluation of automated methods to identify concepts in biomedical text. This paper presents the concept annotations of the Colorado Richly Annotated Full-Text (CRAFT) Corpus, a collection of 97 full-length, open-access biomedical journal articles that have been annotated both semantically and syntactically to serve as a research resource for the biomedical natural-language-processing (NLP) community. CRAFT identifies all mentions of nearly all concepts from nine prominent biomedical ontologies and terminologies: the Cell Type Ontology, the Chemical Entities of Biological Interest ontology, the NCBI Taxonomy, the Protein Ontology, the Sequence Ontology, the entries of the Entrez Gene database, and the three subontologies of the Gene Ontology. The first public release includes the annotations for 67 of the 97 articles, reserving two sets of 15 articles for future text-mining competitions (after which these too will be released). Concept annotations were created based on a single set of guidelines, which has enabled us to achieve consistently high interannotator agreement. As the initial 67-article release contains more than 560,000 tokens (and the full set more than 790,000 tokens), our corpus is among the largest gold-standard annotated biomedical corpora. Unlike most others, the journal articles that comprise the corpus are drawn from diverse biomedical disciplines and are marked up in their entirety. Additionally, with a concept-annotation count of nearly 100,000 in the 67-article subset (and more than 140,000 in the full collection), the scale of conceptual markup is also among the largest of comparable corpora. The concept annotations of the CRAFT Corpus have the potential to significantly advance biomedical text mining by providing a high-quality gold standard for NLP systems. The corpus, annotation guidelines, and other associated resources are freely available at http://bionlp-corpora.sourceforge.net/CRAFT/index.shtml.

  2. Crafted - meisterdatud / Mihkel Tüür

    Index Scriptorium Estoniae

    Tüür, Mihkel, 1976-

    2012-01-01

    12. Alvar Aalto sümpoosion Jyväskyläs 10.-12. augustil 2012 teemal "Crafted". Kuraator Pekka Heikkinen. Pikemalt Mohsen Mostafavi ettekandest "Arhitektuur on materiaalne" ja Jürg Conzetti ettekandest "Strukturaalse tava jätkamine". Autori sõnul jäi kõlama mõte, et meisterlikult ehitatud maja saab olla ainus arhitektuuri tegelik mõõde

  3. The meanings of craft to an occupational therapist.

    Science.gov (United States)

    Harris, Emma

    2008-06-01

    Craft was the first therapeutic occupation of occupational therapy. Since the early days of the profession, the value of craft in practice is a topic that has been discussed with fluctuating interest. Recent discussions by occupational therapists have reinforced that although craft is relevant to occupational therapy, there are uncertainties about its place in contemporary practice. Presently, scholars have identified that occupation is both the center of human experience and the core of our profession. Therefore, this study aimed to begin to clarify the meaning of craft to practice today by gaining a deep understanding of the meanings that one occupational therapist attributes to craft. Using narrative inquiry, data were gathered through a conversation held between the research participant and myself. A reflexive journal was also kept to support this data gathering process. Narrative analysis enabled intimate engagement with the data and the emergence of themes and sub-themes. The findings, in the form of an interpretive story, suggest first, that craft-making has therapeutic value; second, that reasoning about the therapeutic use of craft is similar to reasoning about other therapeutic activities; and third, that personal experience with craft-making can influence the selection of craft as therapeutic media. From this study, further research into the impact personal and professional experiences can have on choice of therapeutic media and an analysis of the sociopolitical context of the meanings that occupational therapists attribute to craft-making is suggested.

  4. Improvement of a separation method for the reduction of secondary waste from the water-jet abrasive suspension cutting technique

    International Nuclear Information System (INIS)

    Brandauer, M.; Gentes, S.; Heneka, A.; Krauss, C.O.; Geckeis, H.; Plaschke, M.; Schild, D.; Tobie, W.

    2017-01-01

    Full text of publication follows. Disassembling the reactor pressure vessel and its built-in components is a huge challenge in the deconstruction of a nuclear power plant. After being exposed to neutron irradiation for years, the activated components need to be disassembled and packed by remote controlled techniques. Underwater disassembling systems have the advantage of the shielding effect of water against radiation. To avoid the generation of aerosols, cold cutting processes are preferred. A cutting method that meets these requirements is the water-jet abrasive suspension cutting technique (WASS). This method provides high flexibility and is immune towards mechanical stress in the components. During the cutting process, a mixture of abrasive particles and radioactive steel particles from the cut components is generated. Depending on the operational conditions, the amount of this secondary waste increases substantially. Therefore, despite of its intrinsic technical benefits, WASS has a serious disadvantage towards other cutting techniques due to the huge disposal costs of secondary waste. During our previous joint research project between KIT and AREVA GmbH called NENAWAS ('New Disposal Methods for the Secondary Waste Treatment of the Water-jet Abrasive Suspension Cutting Technique', funded by the German ministry for education and research, BMBF), a prototype separation device for WASS secondary waste was developed and tested. Using a magnetic filter, steel particles could be successfully separated from the rest of the secondary waste. The separation process is examined using elemental analysis (ICP-OES) for quantification of the separation grade. Additionally, morphologies of particles and particle aggregates before and after the separation process were examined by scanning electron microscopy (SEM). In the abrasive particle fraction after separation of the steel particles a remaining contamination by tiny steel particles could be detected by elemental and

  5. Leading to Crafting: The Relation Between Leadership Perception and Nurses' Job Crafting.

    Science.gov (United States)

    Esteves, Tiago; Pereira Lopes, Miguel

    2017-06-01

    Whenever individuals adapt their jobs to make them closer of their personal preferences, they are performing job crafting. This study aims to investigate if the way nurses perceive their leaders' behaviors is related with job crafting development. To do so, a quantitative analysis was conducted among a group of 325 Portuguese nurses. Results indicate that the perception of an empowering leader was found to be strongly related with the increase of challenges in the work environment, and with the development of stronger relations with direct managers and co-workers, which are two job crafting dimensions. The perception of a directive leader was found to be positively related with the avoidance of performing hindering tasks. Strengthening relations with direct managers and co-workers was found to be particularly related to leadership perception. Theoretical and practical implications are discussed.

  6. Hull-Propeller Interaction and Its Effect on Propeller Cavitation

    DEFF Research Database (Denmark)

    Regener, Pelle Bo

    In order to predict the required propulsion power for a ship reliably and accurately, it is not sufficient to only evaluate the resistance of the hull and the propeller performance in open water alone. Interaction effects between hull and propeller can even be a decisive factor in ship powering...... prediction and design optimization. The hull-propeller interaction coefficients of effective wake fraction, thrust deduction factor, and relative rotative efficiency are traditionally determined by model tests. Self-propulsion model tests consistently show an increase in effective wake fractions when using...... velocities. This offers an opportunity for additional insight into hull-propeller interaction and the propeller’s actual operating condition behind the ship, as the actual (effective) inflow is computed. Self-propulsion simulations at model and full scale were carried out for a bulk carrier, once...

  7. Combination of water-jet dissection and needle-knife as a hybrid knife simplifies endoscopic submucosal dissection.

    Science.gov (United States)

    Lingenfelder, Tobias; Fischer, Klaus; Sold, Moritz G; Post, Stefan; Enderle, Markus D; Kaehler, Georg F B A

    2009-07-01

    The safety and efficacy of endoscopic submucosal dissection (ESD) is very dependent on an effective injection beneath the submucosal lamina and on a controlled cutting technique. After our study group demonstrated the efficacy of the HydroJet in needleless submucosal injections under various physical conditions to create a submucosal fluid cushion (Selective tissue elevation by pressure = STEP technique), the next step was to develop a new instrument to combine the capabilities of an IT-Knife with a high-pressure water-jet in a single instrument. In this experimental study, we compared this new instrument with a standard ESD technique. Twelve gastric ESD were performed in six pigs under endotracheal anesthesia. Square areas measuring 4-cm x 4-cm were marked out on the anterior and posterior wall in the corpus-antrum transition region. The HybridKnife was used as an standard needle knife with insulated tip (i.e., the submucosal injection was performed with an injection needle and only the radiofrequency (RF) part of the HybridKnife was used for cutting (conventional technique)) or the HybridKnife was used in all the individual stages of the ESD, making use of the HybridKnife's combined functions (HybridKnife technique). The size of the resected specimens, the operating time, the frequency with which instruments were changed, the number of bleeding episodes, and the number of injuries to the gastric wall together with the subjective overall assessment of the intervention by the operating physician were recorded. The resected specimens were the same size, with average sizes of 16.96 cm(2) and 15.85 cm(2) resp (p = 0.8125). Bleeding episodes have been less frequent in the HybridKnife group (2.83 vs. 3.5; p = 0.5625). The standard knife caused more injuries to the lamina muscularis propria (0.17 vs. 1.33; p = 0.0313). The operating times had a tendency to be shorter with the HybridKnife technique (47.18 vs. 58.32 minute; p = 0.0313). The combination of a needle

  8. Job Crafting, Employee Well-being, and Quality of Care.

    Science.gov (United States)

    Yepes-Baldó, Montserrat; Romeo, Marina; Westerberg, Kristina; Nordin, Maria

    2018-01-01

    The main objective is to study the effects of job crafting activities of elder care and nursing home employees on their perceived well-being and quality of care in two European countries, Spain and Sweden. The Job Crafting, the General Health, and the Quality of Care questionnaires were administered to 530 employees. Correlations and hierarchical regression analyses were performed. Results confirm the effects of job crafting on quality of care ( r = .291, p employees' well-being ( r = .201, p well-being in Spain and Sweden and with quality of care in Spain. On the contrary, in Sweden, the relationship between job crafting and well-being was not linear. Job crafting contributes significantly to employees' and residents' well-being. Management should promote job crafting to co-create meaningful and productive work. Cultural effects are proposed to explain the differences found.

  9. Modelling job crafting behaviours: Implications for work engagement

    OpenAIRE

    Bakker, Arnold B.; Rodríguez-Muñoz, Alfredo; Sanz Vergel, Ana Isabel

    2016-01-01

    In this study among 206 employees (103 dyads), we followed the job demands–resources approach of job crafting to investigate whether proactively changing one’s work environment influences employee’s (actor’s) own and colleague s (partner’s) work engagement. Using social cognitive theory, we hypothesized that employees would imitate each other’s job crafting behaviours, and therefore influence each other’s work engagement. Results showed that the crafting of social and structural job resources...

  10. 33 CFR 84.24 - High-speed craft.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false High-speed craft. 84.24 Section... RULES ANNEX I: POSITIONING AND TECHNICAL DETAILS OF LIGHTS AND SHAPES § 84.24 High-speed craft. (a) The masthead light of high-speed craft with a length to breadth ratio of less than 3.0 may be placed at a...

  11. Diagnostics of Gun Barrel Propellants

    National Research Council Canada - National Science Library

    Lederman, S

    1983-01-01

    A preliminary investigation of the applicability of the spontaneous Raman diagnostic technique to the determination of the temperature of the propellant gases in the vicinity of the muzzle of a 2Omm...

  12. Cryogenic Propellant Storage and Transfer

    Data.gov (United States)

    National Aeronautics and Space Administration — Space Flight Demonstration development has been canceled in favor of a ground test bed development for of passive/active cryogenic propellant storage, transfer, and...

  13. Cavitation simulation on marine propellers

    DEFF Research Database (Denmark)

    Shin, Keun Woo

    Cavitation on marine propellers causes thrust breakdown, noise, vibration and erosion. The increasing demand for high-efficiency propellers makes it difficult to avoid the occurrence of cavitation. Currently, practical analysis of propeller cavitation depends on cavitation tunnel test, empirical...... criteria and inviscid flow method, but a series of model test is costly and the other two methods have low accuracy. Nowadays, computational fluid dynamics by using a viscous flow solver is common for practical industrial applications in many disciplines. Cavitation models in viscous flow solvers have been...... hydrofoils and conventional/highly-skewed propellers are performed with one of three cavitation models proven in 2D analysis. 3D cases also show accuracy and robustness of numerical method in simulating steady and unsteady sheet cavitation on complicated geometries. Hydrodynamic characteristics of cavitation...

  14. Flagging Economy Propels Financial Education

    Science.gov (United States)

    Manzo, Kathleen Kennedy

    2008-01-01

    On the same day President Bush signed a $150 billion economic-stimulus package in an attempt to head off a recession and offset a crisis in the home-mortgage market, a group of financial experts and educators met a few blocks from the White House to craft a plan for better preparing Americans, young and old, to manage their money. Financial…

  15. Diverse orientations in craft education: Student teachers’ conceptions and perceptions

    Directory of Open Access Journals (Sweden)

    Tarja Kröger

    2016-03-01

    Full Text Available Craft education in Finland has been in a state of change. The concept of a holistic craft process was implemented in the National Core Curriculum in 2004 and the new Curriculum from 2014 strengthened it. Craft and holistic craft is not one unity but includes several orientations. This study aims to research student teachers’ conceptions and perceptions about diverse orientations and the necessity of craft education before they begin their studies in craft pedagogy. Given that the beliefs that student teachers bring to professional learning play a pivotal role in influencing what they can learn from teacher education, they are a subject worthy of investigation. The data consists of on‐line questionnaire answers by student teachers (N=113 at the University of Finland in teacher education in 2014. The on-line questionnaire was answered at the beginning of a basic course in textile craft education at an early stage of their teacher studies. Findings suggest that student teachers conceive of craft education primarily as model-oriented and skill-oriented rather than design-oriented and expression-oriented. Student teachers think that craft education is needed at school, but explanations are not very diverse. The findings of this study can be useful in the process of developing teacher education programmes.

  16. Aircraft Propeller Hub Repair

    Energy Technology Data Exchange (ETDEWEB)

    Muth, Thomas R [ORNL; Peter, William H [ORNL

    2015-02-13

    The team performed a literature review, conducted residual stress measurements, performed failure analysis, and demonstrated a solid state additive manufacturing repair technique on samples removed from a scrapped propeller hub. The team evaluated multiple options for hub repair that included existing metal buildup technologies that the Federal Aviation Administration (FAA) has already embraced, such as cold spray, high velocity oxy-fuel deposition (HVOF), and plasma spray. In addition the team helped Piedmont Propulsion Systems, LLC (PPS) evaluate three potential solutions that could be deployed at different stages in the life cycle of aluminum alloy hubs, in addition to the conventional spray coating method for repair. For new hubs, a machining practice to prevent fretting with the steel drive shaft was recommended. For hubs that were refurbished with some material remaining above the minimal material condition (MMC), a silver interface applied by an electromagnetic pulse additive manufacturing method was recommended. For hubs that were at or below the MMC, a solid state additive manufacturing technique using ultrasonic welding (UW) of thin layers of 7075 aluminum to the hub interface was recommended. A cladding demonstration using the UW technique achieved mechanical bonding of the layers showing promise as a viable repair method.

  17. Which employees craft their jobs and how? Basic dimensions of personality and employees' job crafting behaviour

    NARCIS (Netherlands)

    Bipp, T.; Demerouti, E.

    2015-01-01

    The aim of the current research was to examine to what degree basic personality dimensions serve as determinants of job crafting behaviour and to investigate how this behaviour can be influenced via behavioural intentions. In Study 1, we investigated the relationship of approach and avoidance

  18. Sustainable Innovation of Glass Design and Craft

    DEFF Research Database (Denmark)

    Sparre-Petersen, Maria

    2014-01-01

    , reduction of production and transportation of new glass is desirable (Environmental Protection Agency, 2012), and can be realized by recycling glass, that has already been manufactured, used and collected for recycling, but has ended up in landfills due to the market mechanisms that allow manufacturing...... and deposition of glass is reduced Today glass production predominantly consists of window glass, glass wool for insulation and containers such as bottles and jelly jars. Glass craft and design hold only a fraction of the market. Still there is reason to believe that generation and implementation of new...

  19. Crafts and Craft Education as Expressions of Cultural Heritage: Individual Experiences and Collective Values among an International Group of Women University Students

    Science.gov (United States)

    Kokko, Sirpa; Dillon, Patrick

    2011-01-01

    This paper explores relationships between crafts, craft education and cultural heritage as reflected in the individual experiences and collective values of fifteen female university students of different nationalities. The students (all trainee teachers) were following a course in crafts and craft education as part of an International Study…

  20. 33 CFR 149.310 - What are the muster and embarkation requirements for survival craft?

    Science.gov (United States)

    2010-07-01

    ... embarkation requirements for survival craft? 149.310 Section 149.310 Navigation and Navigable Waters COAST... and embarkation requirements for survival craft? Muster and embarkation arrangements for survival craft must comply with 46 CFR 108.540. ...

  1. Sarawak Bamboo Craft: Symbolism and Phenomenon

    Directory of Open Access Journals (Sweden)

    Arshad Mohd Zaihidee

    2014-04-01

    Full Text Available The relationship between human beings and their environment has stirred reactions between nature and the development of mind and actions that can be discussed using interdisciplinary approaches such as psychology, sociology, anthropology and history, in understanding human thinking and behavior. A psychological approach is intended to evaluate the individual choices and needs in society. A sociological approach details the various patterns in the social organization. An anthropological approach is tied with culture and belief to fulfil human needs which are based on their habitat, while a historical approach looks at the development which is related to the past. Dimensions of experiences, order and logic, selective elaboration and expressions are used to analyze the bamboo craft of Iban, Melanau and Bidayuh societies in Sarawak long-houses. The existence of constitutive, moral, expressive and cognitive symbols has been interpreted based on a theoretical framework that has been developed by Langer Art Theory, Parsons Social Theory and Kaplan Culture Theory. The values and meaning formed are interpreted to understand matters related to the lives of villagers and the finding suggests that bamboo craft expresses the multi-ethnic mind and character in the socio-culture of long- houses in Sarawak.

  2. Searching the Soul: Veterans and Their Arts and Crafts

    Science.gov (United States)

    Hasio, Cindy

    2011-01-01

    For military veterans suffering from the long-term trauma of warfare, arts and crafts become much more than the fabrication of relics; they can literally save the spirit. Dialogue and interaction between the veterans, volunteers, and staff are crucial to the success of veterans' arts and crafts program. The purpose of this research was threefold.…

  3. Formation control of marine surface craft: a Lagrangian approach

    DEFF Research Database (Denmark)

    Ihle, Ivar-Andre F.; Jouffroy, Jerome; Fossen, Thor I.

    2006-01-01

    This paper presents a method for formation control of marine surface craft inspired by Lagrangian mechanics. The desired formation configuration and response of the marine surface craft are given as a set of constraints in analytical mechanics. Thus, constraints forces arise and feedback from...

  4. Creating Chicago History: Making Outreach Craft Activities Meaningful

    Science.gov (United States)

    Karp, Madeline

    2012-01-01

    When it comes to having a traveling outreach activity for a museum, a craft can seem like the perfect solution. It can seemingly be all things at once--educational, quick and fun. But, if poorly constructed, crafts can also have serious fallbacks. Using the Chicago History Museum and the Millennium Park Family Fun Festival as a case study, this…

  5. Craft Lessons: Teaching Writing K-8. Second Edition

    Science.gov (United States)

    Fletcher, Ralph; Portalupi, JoAnn

    2007-01-01

    Since its publication in 1998 Craft Lessons has become a mainstay of writing teachers, both new and experienced. Practical lessons--each printed on one page--and the instructional language geared to three grade-level groupings: K-2, 3-4, and 5-8 are contained in this book. In the decade since Craft Lessons' publication the world has changed in…

  6. Learning Practices of Femininity through Gendered Craft Education in Finland

    Science.gov (United States)

    Kokko, Sirpa

    2009-01-01

    This paper discusses the processes and practices that link crafts and gender in the upbringing and education of girls. The paper is based on a study conducted among female primary school trainee teachers in Finland. The data are comprised of their experiences with crafts as schoolgirls. The methods of the study were memory work and writing of…

  7. 33 CFR 146.120 - Manning of survival craft.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Manning of survival craft. 146.120 Section 146.120 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... craft. The owner, the owner's agent, or the person in charge shall assign a person to each life float...

  8. Students' Attitudes towards Craft and Technology in Iceland and Finland

    Science.gov (United States)

    Thorsteinsson, Gísli; Ólafsson, Brynjar; Autio, Ossi

    2012-01-01

    Craft education in both Finland and Iceland originated over 140 years ago and was influenced by the Scandinavian Sloyd pedagogy. Since then, the subject has moved away from craft and towards technology, with the aim being to increase students' technological abilities. In the beginning, the subject largely focused on the students copying artefacts,…

  9. 46 CFR 108.520 - Type of survival craft.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Type of survival craft. 108.520 Section 108.520 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Lifesaving Equipment § 108.520 Type of survival craft. (a) Each lifeboat must be a fire-protected...

  10. Craft-Art as a Basis for Human Activity

    Science.gov (United States)

    Karppinen, Seija

    2008-01-01

    This article based on my doctoral thesis examines the Basic Arts Education system in Finland, focusing on Basic Crafts Education and its description through action concepts. The main task of the study was to create a concept model. In the first part of the study a concept map was created from the practice of Basic Crafts Education. The aim of the…

  11. The comparative risk assessment framework and tools (CRAFT)

    Science.gov (United States)

    Southern Research Station. USDA Forest Service

    2010-01-01

    To help address these challenges, the USDA Forest Service’s Eastern Forest Environmental Threat Assessment Center (EFETAC) and the University of North Carolina Asheville’s National Environmental Modeling and Analysis Center (NEMAC) designed a planning framework, called the Comparative Risk Assessment Framework and Tools (CRAFT). CRAFT is...

  12. Craft Training in Russia: Theory and Practice of Development

    Science.gov (United States)

    Romantsev, Gennadij M.; Efanov, Andrei V.; Moiseev, Andrei V.; Bychkova, Ekaterina Yu.; Karpova, Natalia P.; Tidemann, Bruno

    2016-01-01

    The relevance of the research topic is substantiated by the social commitment to the establishment of a system of craft training focused on training personnel for craft enterprises. The purpose of the article is to provide theoretical and methodological substantiation of the necessity to provide organizational and pedagogical foundations for the…

  13. Empowering leadership and job crafting: The role of employee optimism.

    Science.gov (United States)

    Thun, Sylvi; Bakker, Arnold B

    2018-06-08

    The objective of this study was to test the relationship between empowering leadership and job crafting and to examine the moderating role of optimism as a personal resource. We hypothesized that the association between empowering leadership and job crafting would be stronger for employees with high (vs. low) levels of optimism. A total of 331 Norwegian workers from a variety of occupations participated in our study. Results of structural equation modelling analysis generally supported our hypotheses. Empowering leadership was positively related to 3 of the 4 job crafting strategies investigated (increasing structural job resources, increasing social job resources, and increasing challenging job demands; but not reducing hindrance job demands). Moreover, as hypothesized, optimism strengthened the empowering leadership-job crafting relationship for increasing structural resources and increasing challenging demands. The results suggest that empowering leadership is an important antecedent of job crafting strategies, except for reducing hindrance demands. The implications of these findings are discussed. Copyright © 2018 John Wiley & Sons, Ltd.

  14. Employees’ perceived opportunities to craft and in-role performance : The mediating role of job crafting and work engagement

    NARCIS (Netherlands)

    Van Wingerden, Jessica; Poell, R.F.

    2017-01-01

    The present study was designed to gain knowledge of the relationship between employees' perceived opportunities to craft, their actual job crafting behavior and, in line with JD-R theory, subsequently their work engagement and performance. Although scholars have suggested that employees' perceived

  15. Propeller Flaps: A Literature Review.

    Science.gov (United States)

    Sisti, Andrea; D'Aniello, Carlo; Fortezza, Leonardo; Tassinari, Juri; Cuomo, Roberto; Grimaldi, Luca; Nisi, Giuseppe

    2016-01-01

    Since their introduction in 1991, propeller flaps are increasingly used as a surgical approach to loss of substance. The aim of this study was to evaluate the indications and to verify the outcomes and the complication rates using this reconstructing technique through a literature review. A search on PubMed was performed using "propeller flap", "fasciocutaneous flap", "local flap" or "pedicled flap" as key words. We selected clinical studies using propeller flaps as a reconstructing technique. We found 119 studies from 1991 to 2015. Overall, 1,315 propeller flaps were reported in 1,242 patients. Most frequent indications included loss of substance following tumor excision, repair of trauma-induced injuries, burn scar contractures, pressure sores and chronic infections. Complications were observed in 281/1242 patients (22.6%) occurring more frequently in the lower limbs (31.8%). Partial flap necrosis and venous congestion were the most frequent complications. The complications' rate was significantly higher in infants (70 years old) but there was not a significant difference between the sexes. Trend of complication rate has not improved during the last years. Propeller flaps showed a great success rate with low morbidity, quick recovery, good aesthetic outcomes and reduced cost. The quality and volume of the transferred soft tissue, the scar orientation and the possibility of direct donor site closure should be considered in order to avoid complications. Indications for propeller flaps are small- or medium-sized defects located in a well-vascularized area with healthy surrounding tissues. Copyright © 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  16. Laser-propelled ram accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Sasoh, A. [Tohoku Univ., Sendai (Japan). Inst. of Fluid Science

    2000-11-01

    The concept of 'laser-propelled ram accelerator (L-RAMAC)' is proposed. Theoretically it is capable of achieving a higher launch speed than that by a chemical ram accelerator because a higher specific energy can be input to the propellant gas. The laser beam is supplied through the muzzle, focused as an annulus behind the base of the projectile. The performance of L-RAMAC is analized based on generalized Rankine-Hugoniot relations, suggesting that a superorbital muzzle speed is achievable out of this device. (orig.)

  17. Large Propellant Tank Cryo-Cooler (LPTC)

    Data.gov (United States)

    National Aeronautics and Space Administration — In rocket test and launch facilities, cryogenic propellants stored in tanks boils off due to heat leakage, with the following impacts:Ø   Waste, propellants boil off...

  18. Quadcopter thrust optimization with ducted-propeller

    Directory of Open Access Journals (Sweden)

    Kuantama Endrowednes

    2017-01-01

    Full Text Available In relation to quadcopter body frame model, propeller can be categorized into propeller with ducted and without ducted. This study present differences between those two using CFD (Computational Fluid Dynamics method. Both categories utilize two blade-propeller with diameter of 406 (mm. Propeller rotation generates acceleration per time unit on the volume of air. Based on the behavior of generated air velocity, ducted propeller can be modeled into three versions. The generated thrust and performance on each model were calculated to determine the best model. The use of ducted propeller increases the total weight of quadcopter and also total thrust. The influence of this modeling were analyzed in detail with variation of angular velocity propeller from 1000 (rpm to 9000 (rpm. Besides the distance between propeller tip and ducted barrier, the size of ducted is also an important part in thrust optimization and total weight minimization of quadcopter.

  19. Seawater Immersion of GEM II Propellant

    National Research Council Canada - National Science Library

    Merrill, Calude

    1999-01-01

    ... (% AP lost/week aged in seawater) and intercepts that depend on sample size. Friction and impact data on dried aged propellant samples showed no increased burning hazard compared with propellant not exposed to water...

  20. Job crafting: Towards a new model of individual job redesign

    Directory of Open Access Journals (Sweden)

    Maria Tims

    2010-12-01

    Research purpose: The purpose of the study was to fit job crafting in job design theory. Motivation for the study: The study was an attempt to shed more light on the types of proactive behaviours of individual employees at work. Moreover, we explored the concept of job crafting and its antecedents and consequences. Research design, approach and method: A literature study was conducted in which the focus was first on proactive behaviour of the employee and then on job crafting. Main findings: Job crafting can be seen as a specific form of proactive behaviour in which the employee initiates changes in the level of job demands and job resources. Job crafting may be facilitated by job and individual characteristics and may enable employees to fit their jobs to their personal knowledge, skills and abilities on the one hand and to their preferences and needs on the other hand. Practical/managerial implications: Job crafting may be a good way for employees to improve their work motivation and other positive work outcomes. Employees could be encouraged to exert more influence on their job characteristics. Contribution/value-add: This article describes a relatively new perspective on active job redesign by the individual, called job crafting, which has important implications for job design theories.

  1. Innovative boron nitride-doped propellants

    Directory of Open Access Journals (Sweden)

    Thelma Manning

    2016-04-01

    Full Text Available The U.S. military has a need for more powerful propellants with balanced/stoichiometric amounts of fuel and oxidants. However, balanced and more powerful propellants lead to accelerated gun barrel erosion and markedly shortened useful barrel life. Boron nitride (BN is an interesting potential additive for propellants that could reduce gun wear effects in advanced propellants (US patent pending 2015-026P. Hexagonal boron nitride is a good lubricant that can provide wear resistance and lower flame temperatures for gun barrels. Further, boron can dope steel, which drastically improves its strength and wear resistance, and can block the formation of softer carbides. A scalable synthesis method for producing boron nitride nano-particles that can be readily dispersed into propellants has been developed. Even dispersion of the nano-particles in a double-base propellant has been demonstrated using a solvent-based processing approach. Stability of a composite propellant with the BN additive was verified. In this paper, results from propellant testing of boron nitride nano-composite propellants are presented, including closed bomb and wear and erosion testing. Detailed characterization of the erosion tester substrates before and after firing was obtained by electron microscopy, inductively coupled plasma and x-ray photoelectron spectroscopy. This promising boron nitride additive shows the ability to improve gun wear and erosion resistance without any destabilizing effects to the propellant. Potential applications could include less erosive propellants in propellant ammunition for large, medium and small diameter fire arms.

  2. Propelling arboriculture into the future

    Science.gov (United States)

    E. Gregory McPherson

    2011-01-01

    Research is the engine that propels arboriculture and urban forestry into the future. New knowledge, technologies, and tools provide arborists with improved tree care practices that result in healthier urban forests. The ISA Science and Research Committee (SRC) is composed of 13 professionals and researchers who are dedicated to elevating the importance of research...

  3. Plasma ignition of LOVA propellants

    NARCIS (Netherlands)

    Driel, C.A. van; Boluijt, A.G.; Schilt, A.

    2010-01-01

    Ignition experiments were performed using a gun simulator which is equipped with a burst disk. This equipment facilitates the application of propellant loading densities which are comparable to those applied in regular ammunitions. For this study the gun simulator was equipped with a plasma jet

  4. THE PROPELLER AND THE FROG

    International Nuclear Information System (INIS)

    Pan, Margaret; Chiang, Eugene

    2010-01-01

    'Propellers' in planetary rings are disturbances in ring material excited by moonlets that open only partial gaps. We describe a new type of co-orbital resonance that can explain the observed non-Keplerian motions of propellers. The resonance is between the moonlet underlying the propeller and co-orbiting ring particles downstream of the moonlet where the gap closes. The moonlet librates within the gap about an equilibrium point established by co-orbiting material and stabilized by the Coriolis force. In the limit of small libration amplitude, the libration period scales linearly with the gap azimuthal width and inversely as the square root of the co-orbital mass. The new resonance recalls but is distinct from conventional horseshoe and tadpole orbits; we call it the 'frog' resonance, after the relevant term in equine hoof anatomy. For a ring surface density and gap geometry appropriate for the propeller Bleriot in Saturn's A ring, our theory predicts a libration period of ∼4 years, similar to the ∼3.7 year period over which Bleriot's orbital longitude is observed to vary. These librations should be subtracted from the longitude data before any inferences about moonlet migration are made.

  5. Guides crafting meaning and identity in a flexible working life

    DEFF Research Database (Denmark)

    Meged, Jane Widtfeldt

    2017-01-01

    and adding a critical perspective, we understand the guides’ agency, and how they craft scope, tasks and relations in order to sustain a positive self-image and a meaningful working life. Comparing certified guides’ job-crafting practices, we learn that guides are alike across the three countries......Certified guides are exemplary, well-educated, self-employed, casual labourers in a liberal and competitive job market. Applying grounded theory, this exploratory study builds on in-depth qualitative interviews with Danish, Italian and French certified guides. Informed by the theory of job crafting...

  6. 47 CFR 80.223 - Special requirements for survival craft stations.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Special requirements for survival craft... requirements for survival craft stations. (a) Survival craft stations capable of transmitting on: (1) 2182 kHz... operate with A3E or A3N emission. (b) Survival craft stations must be able to receive the frequency and...

  7. 46 CFR 117.205 - Survival craft-vessels operating on limited coastwise routes.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Survival craft-vessels operating on limited coastwise... PASSENGERS LIFESAVING EQUIPMENT AND ARRANGEMENTS Number and Type of Survival Craft § 117.205 Survival craft... the survival craft required by §§ 117.204 (a) through (d) of this part, as applicable. (b) Each vessel...

  8. 46 CFR 111.75-16 - Lighting of survival craft and rescue boats.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Lighting of survival craft and rescue boats. 111.75-16... craft and rescue boats. (a) During preparation, launching, and recovery, each survival craft and rescue... of circuits must be such that the lighting for adjacent launching stations for survival craft or...

  9. 46 CFR 108.540 - Survival craft muster and embarkation arrangements.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Survival craft muster and embarkation arrangements. 108... OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Lifesaving Equipment § 108.540 Survival craft muster and... craft muster station and embarkation station for a survival craft which is boarded before it is launched...

  10. 46 CFR 117.204 - Survival craft-vessels operating on coastwise routes.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Survival craft-vessels operating on coastwise routes... PASSENGERS LIFESAVING EQUIPMENT AND ARRANGEMENTS Number and Type of Survival Craft § 117.204 Survival craft... allowed, the following survival craft requirements apply when not engaged in an overnight voyage: (1...

  11. 46 CFR 117.206 - Survival craft-vessels operating on Great Lakes routes.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Survival craft-vessels operating on Great Lakes routes... PASSENGERS LIFESAVING EQUIPMENT AND ARRANGEMENTS Number and Type of Survival Craft § 117.206 Survival craft... vessel certificated to operate on a Great Lakes route must be provided with the survival craft required...

  12. Drag and Torque on Locked Screw Propeller

    Directory of Open Access Journals (Sweden)

    Tomasz Tabaczek

    2014-09-01

    Full Text Available Few data on drag and torque on locked propeller towed in water are available in literature. Those data refer to propellers of specific geometry (number of blades, blade area, pitch and skew of blades. The estimation of drag and torque of an arbitrary propeller considered in analysis of ship resistance or propulsion is laborious. The authors collected and reviewed test data available in the literature. Based on collected data there were developed the empirical formulae for estimation of hydrodynamic drag and torque acting on locked screw propeller. Supplementary CFD computations were carried out in order to prove the applicability of the formulae to modern moderately skewed screw propellers.

  13. Major factors influencing craft productivity in nuclear power plant construction

    International Nuclear Information System (INIS)

    Borcherding, J.D.; Sebastian, S.J.

    1980-01-01

    This paper reports on a research study whose objective was to determine the most influential factors adversely affecting craft productivity in nuclear power plant construction from the perspective of the tradesmen employed at the sites. Data were collected through the use of a questionnaire survey and group interview sessions, predominantly with workmen, at six nuclear power plant construction projects. Craftsmen were chosen as the major data base because of their awareness of how their time would actually be spent on the project. Topics considered include the factors influencing craft productivity, material availability, redoing work, crew interfacing, overcrowded work areas, instruction time, inspection delays, craft turnover, craft absenteeism, foreman changes, foreman incompetence, engineering design lead time, comprehensive scheduling of the design function, the responsibility of the utility, value engineering, plant standardization, the effective utilization of the planning and scheduling system, and the labor-management committee

  14. Construction and Validation of the Perceived Opportunity to Craft Scale.

    Science.gov (United States)

    van Wingerden, Jessica; Niks, Irene M W

    2017-01-01

    We developed and validated a scale to measure employees' perceived opportunity to craft (POC) in two separate studies conducted in the Netherlands (total N = 2329). POC is defined as employees' perception of their opportunity to craft their job. In Study 1, the perceived opportunity to craft scale (POCS) was developed and tested for its factor structure and reliability in an explorative way. Study 2 consisted of confirmatory analyses of the factor structure and reliability of the scale as well as examination of the discriminant and criterion-related validity of the POCS. The results indicated that the scale consists of one dimension and could be reliably measured with five items. Evidence was found for the discriminant validity of the POCS. The scale also showed criterion-related validity when correlated with job crafting (+), job resources (autonomy +; opportunities for professional development +), work engagement (+), and the inactive construct cynicism (-). We discuss the implications of these findings for theory and practice.

  15. Integrated Design of Semi-Displacement Patrol Crafts

    National Research Council Canada - National Science Library

    Gillespy, Andrew J

    2008-01-01

    ... of any one change on the entire system. The initial design of smaller patrol craft is especially difficult due to the lack of design tools able to deal with ships of small size operating in the semi-planing region...

  16. The Computer and the Writer's Craft: Implications for Teachers.

    Science.gov (United States)

    Brockmann, R. John; McCauley, Rebecca J.

    1984-01-01

    Examines how computers as a medium for communication affect the craft of writing, and subsequently affect teaching approaches. Discusses the need for teaching online document design and problem-solving processes as they relate to the communication process. (HTH)

  17. Constructing knowledge through perceptual processes in making craft-art

    Directory of Open Access Journals (Sweden)

    Milla Ojala

    2013-10-01

    Full Text Available The focus of the study is on the knowledge that is constructed through perceptual processes during craft making in the context of the Finnish Basic Education in the Arts (BEA system. Craft studies in the BEA are defined as craft-art. The research method used is the grounded theory. The data consists of seven interviews and participant observations. Participants in the study are adolescents who study craft-art in the BEA system in Visual Art School, Aimo in Hämeenlinna. The aim of the article is to present, define and reflect on the concepts, properties and dimensions concerning perceptual processes that are discovered in this stage of the study following grounded theory procedures. The perceptual processes are an essential means of constructing knowledge in craft-art. Consequently, one aim of the study is to discuss how these processes are connected to various types of knowledge. The perceptual processes are described by seven concepts: imitative, anticipative, evaluative, experimental, emotional, temporal and bodily perceptions. They indicate on a conceptual level the characteristic of knowledge constructed through perceptual processes in craft-art. Further, theconcepts have several properties that can vary dimensionally between two qualities. The properties are activity, function and position. The dimensions of the properties vary from active to passive, formal to informal and internal to external. In conclusion, the concepts can describe a large range of incidents in different situations. They also seem to describe well the practice of  craft-art and there are several connections with pre-existing concepts of knowledge.Keywords: Craft, Knowledge, Perceptual process, Basic Education in the Arts, Grounded Theory 

  18. Craft's brand equity in CZ, focusing on canoeing

    OpenAIRE

    Šťastný, Šimon

    2013-01-01

    Title: Craft's brand equity in CZ, focusing on flat water canoeing. Objectives: The objective of this dissertation is to find out what is the Craft's brand equity and to suggest how to improve it on the Czech market. That would be based on marketing research and supplementary interview. I will be using marketing research and supplementary interview. Methods: In this dissertation the method of electronic questioning was used. The questionnaires were sent by email address after first contact on...

  19. Minimum Plate Thickness in High-Speed Craft

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Zhang, Shengming

    1998-01-01

    The minimum plate thickness requirements specified by the classification societies for high-speed craft are supposed to ensure adequate resistance to impact loads such as collision with floating objects and objects falling on the deck. The paper presents analytical methods of describing such impact...... phenomena and proposes performance requirements instead of thickness requirements for hull panels in high-speed craft made of different building materials....

  20. Experimental research on air propellers

    Science.gov (United States)

    Durand, William F

    1918-01-01

    The purposes of the experimental investigation on the performance of air propellers described in this report are as follows: (1) the development of a series of design factors and coefficients drawn from model forms distributed with some regularity over the field of air-propeller design and intended to furnish a basis of check with similar work done in other aerodynamic laboratories, and as a point of departure for the further study of special or individual types and forms; (2) the establishment of a series of experimental values derived from models and intended for later use as a basis for comparison with similar results drawn from certain selected full-sized forms and tested in free flight.

  1. A theoretical and experimental investigation of propeller performance methodologies

    Science.gov (United States)

    Korkan, K. D.; Gregorek, G. M.; Mikkelson, D. C.

    1980-01-01

    This paper briefly covers aspects related to propeller performance by means of a review of propeller methodologies; presentation of wind tunnel propeller performance data taken in the NASA Lewis Research Center 10 x 10 wind tunnel; discussion of the predominent limitations of existing propeller performance methodologies; and a brief review of airfoil developments appropriate for propeller applications.

  2. The influence of the choice of propeller design tool on propeller performance

    OpenAIRE

    Skåland, Edvard Knutsen

    2016-01-01

    In this master thesis different propeller design and analysis methods are presented and compared in terms of the accuracy and computational efficiency of their theory. These methods include lifting line, vortex lattice lifting surface and panel methods. A propeller design program based on lifting line theory was developed by the author. This program has been used together with the propeller design programs OpenProp and AKPD to make six propeller designs. The designs are based o...

  3. Propeller Test Facilities Â

    Data.gov (United States)

    Federal Laboratory Consortium — Description: Three electrically driven whirl test stands are used to determine propeller (or other rotating device) performance at various rotational speeds. These...

  4. Nonsteady Combustion Mechanisms of Advanced Solid Propellants

    National Research Council Canada - National Science Library

    Branch, Melvyn

    1997-01-01

    .... The individual tasks which we are studying will pursue solid propellant decomposition under unsteady conditions, nonsteady aspects of gas phase flame structure measurements, numerical modeling...

  5. Injection dynamics of gelled propellants

    Science.gov (United States)

    Yoon, Changjin

    Gel propellants have been recognized as attractive candidates for future propulsion systems due to the reduced tendency to spill and the energy advantages over solid propellants. One of strong benefits emphasized in gel propellant applications is a throttling capability, but the accurate flow control is more complicated and difficult than with conventional Newtonian propellants because of the unique rheological behaviors of gels. This study is a computational effort directed to enhance understanding of the injector internal flow characteristics for gel propellants under rocket injection conditions. In simulations, the emphasized rheology is a shear-thinning which represents a viscosity decrease with increasing a shear rate. It is described by a generalized Newtonian fluid constitutive equation and Carreau-Yasuda model. Using this rheological model, two injection schemes are considered in the present study: axially-fed and cross-fed injection for single-element and multi-element impinging injectors, respectively. An axisymmetric model is developed to describe the axially-fed injector flows and fully three-dimensional model is utilized to simulate cross-fed injector flows. Under axially-fed injection conditions investigated, three distinct modes, an unsteady, steady, and hydraulic flip mode, are observed and mapped in terms of Reynolds number and orifice design. In an unsteady mode, quasi-periodic oscillations occur near the inlet lip leading mass pulsations and viscosity fluctuations at the orifice exit. This dynamic behavior is characterized using a time-averaged discharge coefficient, oscillation magnitude and frequency by a parametric study with respect to an orifice design, Reynolds number and rheology. As a result, orifice exit flows for gel propellants appear to be significantly influenced by a viscous damping and flow resistance due to a shear thinning behavior and these are observed in each factors considered. Under conditions driven by a manifold crossflow

  6. Detail in architecture: Between arts & crafts

    Science.gov (United States)

    Dulencin, Juraj

    2016-06-01

    Architectural detail represents an important part of architecture. Not only can it be used as an identifier of a specific building but at the same time enhances the experience of the realized project. Within it lie the signs of a great architect and clues to understanding his or her way of thinking. It is therefore the central topic of a seminar offered to architecture students at the Brno University of Technology. During the course of the semester-long class the students acquaint themselves with atypical architectural details of domestic and international architects by learning to read them, understand them and subsequently draw them by creating architectural blueprints. In other words, by general analysis of a detail the students learn theoretical thinking of its architect who, depending on the nature of the design, had to incorporate a variety of techniques and crafts. Students apply this analytical part to their own architectural detail design. The methodology of the seminar consists of experiential learning by project management and is complemented by a series of lectures discussing a diversity of details as well as materials and technologies required to implement it. The architectural detail design is also part of students' bachelors thesis, therefore, the realistic nature of their blueprints can be verified in the production process of its physical counterpart. Based on their own documentation the students choose the most suitable manufacturing process whether it is supplied by a specific technology or a craftsman. Students actively participate in the production and correct their design proposals in real scale with the actual material. A student, as a future architect, stands somewhere between a client and an artisan, materializes his or her idea and adjusts the manufacturing process so that the final detail fulfills aesthetic consistency and is in harmony with its initial concept. One of the very important aspects of the design is its economic cost, an

  7. High burn rate solid composite propellants

    Science.gov (United States)

    Manship, Timothy D.

    High burn rate propellants help maintain high levels of thrust without requiring complex, high surface area grain geometries. Utilizing high burn rate propellants allows for simplified grain geometries that not only make production of the grains easier, but the simplified grains tend to have better mechanical strength, which is important in missiles undergoing high-g accelerations. Additionally, high burn rate propellants allow for a higher volumetric loading which reduces the overall missile's size and weight. The purpose of this study is to present methods of achieving a high burn rate propellant and to develop a composite propellant formulation that burns at 1.5 inches per second at 1000 psia. In this study, several means of achieving a high burn rate propellant were presented. In addition, several candidate approaches were evaluated using the Kepner-Tregoe method with hydroxyl terminated polybutadiene (HTPB)-based propellants using burn rate modifiers and dicyclopentadiene (DCPD)-based propellants being selected for further evaluation. Propellants with varying levels of nano-aluminum, nano-iron oxide, FeBTA, and overall solids loading were produced using the HTPB binder and evaluated in order to determine the effect the various ingredients have on the burn rate and to find a formulation that provides the burn rate desired. Experiments were conducted to compare the burn rates of propellants using the binders HTPB and DCPD. The DCPD formulation matched that of the baseline HTPB mix. Finally, GAP-plasticized DCPD gumstock dogbones were attempted to be made for mechanical evaluation. Results from the study show that nano-additives have a substantial effect on propellant burn rate with nano-iron oxide having the largest influence. Of the formulations tested, the highest burn rate was a 84% solids loading mix using nano-aluminum nano-iron oxide, and ammonium perchlorate in a 3:1(20 micron: 200 micron) ratio which achieved a burn rate of 1.2 inches per second at 1000

  8. Experimental Investigation of a Wing-in-Ground Effect Craft

    Directory of Open Access Journals (Sweden)

    M. Mobassher Tofa

    2014-01-01

    Full Text Available The aerodynamic characteristics of the wing-in-ground effect (WIG craft model that has a noble configuration of a compound wing was experimentally investigated and Universiti Teknologi Malaysia (UTM wind tunnel with and without endplates. Lift and drag forces, pitching moment coefficients, and the centre of pressure were measured with respect to the ground clearance and the wing angle of attack. The ground effect and the existence of the endplates increase the wing lift-to-drag ratio at low ground clearance. The results of this research work show new proposed design of the WIG craft with compound wing and endplates, which can clearly increase the aerodynamic efficiency without compromising the longitudinal stability. The use of WIG craft is representing an ambitious technology that will help in reducing time, effort, and money of the conventional marine transportation in the future.

  9. Experimental investigation of a wing-in-ground effect craft.

    Science.gov (United States)

    Tofa, M Mobassher; Maimun, Adi; Ahmed, Yasser M; Jamei, Saeed; Priyanto, Agoes; Rahimuddin

    2014-01-01

    The aerodynamic characteristics of the wing-in-ground effect (WIG) craft model that has a noble configuration of a compound wing was experimentally investigated and Universiti Teknologi Malaysia (UTM) wind tunnel with and without endplates. Lift and drag forces, pitching moment coefficients, and the centre of pressure were measured with respect to the ground clearance and the wing angle of attack. The ground effect and the existence of the endplates increase the wing lift-to-drag ratio at low ground clearance. The results of this research work show new proposed design of the WIG craft with compound wing and endplates, which can clearly increase the aerodynamic efficiency without compromising the longitudinal stability. The use of WIG craft is representing an ambitious technology that will help in reducing time, effort, and money of the conventional marine transportation in the future.

  10. 78 FR 4038 - Critical Parts for Airplane Propellers

    Science.gov (United States)

    2013-01-18

    ... manufacturers are not required to provide information concerning propeller critical part design, manufacture, or... engineering, manufacturing, and service management processes should provide clear information for propeller... manufacture critical parts for airplane propellers update their manuals to record engineering, manufacture...

  11. KAPPEL Propeller. Development of a Marine Propeller with Non-planar Lifting Surfaces

    DEFF Research Database (Denmark)

    Kappel, J.; Andersen, Poul

    2002-01-01

    The principle of non-planar lifting surfaces is applied to the design of modern aircraft wings to obtain better lift to drag ratios. Whereas a pronounced fin or "winglet" at the wingtip has been developed for aircraft, the application of the non-planar principle to marine propellers, dealt...... with in this paper, has led to the KAPPEL propeller with blades curved towards the suction side integrating the fin or winglet into the propeller blade. The combined theoretical, experimental and practical approach to develop and design marine propellers with non-planar lifting surfaces has resulted in propellers...

  12. Classification of Intact Stability Standards for Dynamically Supported Craft.

    Science.gov (United States)

    1979-10-01

    introduced (by the U.S. Navy) in the late 1950’s. Both military and commercial applications of this type have since proved very successful . From the... successful and safe planing craft have been built for military, commercial and private use. The stability of planing craft, however, is an extremely...forlces. Broaching- [ n I, 111, I ikeA LL) tOCCUr in suvvre following seas, when the Cr aft runs do L tht ! act of ort wav docd slope- ts bovw Ma’ thes

  13. Formation control of surface marine craft using Lagrange multipliers

    DEFF Research Database (Denmark)

    Ihle, Ivar-Andre F.; Jouffroy, Jerome; Fossen, Thor I.

    We propose a method for constructing control laws for formation control of marine craft using classical tools from analytical mechanics. The control law is based on applying inter-vessel constraint functions which again impose forces on the individual vessels that maintain the given constraints...... on the total system. In this way, a formation can be assembled and stay together when exposed to external forces. A brief comparison with other control designs for a group of marine craft is done. Further, control laws for formation assembling (with dynamic positioning), and formation keeping during...

  14. Supercritical Fluid Processing of Propellant Polymers

    Science.gov (United States)

    1991-01-01

    of insoluble material present in the polymeric neopentyl glycol azelate (NPGA) binder. Laub (2) summarizes (from Refs 3 & 4) the various polymeric...binders used in composite propellant formulations for DOD missile systems. e.g., these include: polyneopentyl glycol azelate (NPGA) in HAWK. hydroxy...systems. Composite smokeless propellants containing polyethylene glycol (PEG), polyethylene glycol adepate (PEGA) and polycaprolactone are currently under

  15. Development of hydrazinium nitroformate based solid propellants

    NARCIS (Netherlands)

    Schöyer, H.F.R.; Schnorhk, A.J.; Korting, P.A.O.G.; Lit, P.J. van; Mul, J.M.; Gadiot, G.; Meulenbrugge, J.J.

    1995-01-01

    The development of new high-performance propellant combinations requires the establishment of safety and handling characteristics and thermodynamic decomposition and explosive properties. This paper addresses the early development phases of a new composite solid propellant based on HNF as oxidizer

  16. Green plasticizers for multibase gun propellants (Lecture)

    NARCIS (Netherlands)

    Schoolderman, C.; Driel, C.A. van; Zebregs, M.

    2007-01-01

    TNO Defence, Security and Safety has a long history of research on gun propellants. Areas investigated are formulating (new ingredients, optimization), manufacturing, charge design and lifetime assessment [1,2,3,4,5]. In conventional propellants inert plasticizers are used to alter performance,

  17. Transformational leadership, adaptability, and job crafting : the moderating role of organizational identification.

    NARCIS (Netherlands)

    Wang, H.; Demerouti, E.; Le Blanc, P.M.

    In this study, we aim to explore the link between transformational leadership and job crafting. We predict that transformational leadership will stimulate employee job crafting (seeking resources, seeking challenges, and reducing demands) by increasing their adaptability; but that transformational

  18. Marian Roberts, Developing the Craft of Mediation: Reflections on Theory and Practice

    Directory of Open Access Journals (Sweden)

    Ghislaine M. Lanteigne

    2008-10-01

    Full Text Available In Developing the Craft of Mediation, Marian Roberts proposes that mediation is akin to a craft with its focus on learning from experience and from others working in the field to develop and master knowledge and skills.

  19. Tests on thirteen navy type model propellers

    Science.gov (United States)

    Durand, W F

    1927-01-01

    The tests on these model propellers were undertaken for the purpose of determining the performance coefficients and characteristics for certain selected series of propellers of form and type as commonly used in recent navy designs. The first series includes seven propellers of pitch ratio varying by 0.10 to 1.10, the area, form of blade, thickness, etc., representing an arbitrary standard propeller which had shown good results. The second series covers changes in thickness of blade section, other things equal, and the third series, changes in blade area, other things equal. These models are all of 36-inch diameter. Propellers A to G form the series on pitch ratio, C, N. I. J the series on thickness of section, and K, M, C, L the series on area. (author)

  20. Small-Scale Shock Testing of Propellants and Ingredients

    National Research Council Canada - National Science Library

    Dawley, S

    2004-01-01

    .... The use of small-scale gap testing to evaluate the shock sensitivity of individual propellant ingredients and propellant formulations is a valuable method for experimentally establishing shock...

  1. Structure of Partially Premixed Flames and Advanced Solid Propellants

    National Research Council Canada - National Science Library

    Branch, Melvyn

    1998-01-01

    The combustion of solid rocket propellants of advanced energetic materials involves a complex process of decomposition and condensed phase reactions in the solid propellant, gaseous flame reactions...

  2. A Study of Flame Physics and Solid Propellant Rocket Physics

    National Research Council Canada - National Science Library

    Buckmaster, John

    2007-01-01

    ..., the combustion of heterogeneous propellants containing aluminum, the use of a genetic algorithm to optimally define false-kinetics parameters in propellant combustion modeling, the calculation of fluctuations...

  3. Job crafting, work engagement, and psychological distress among Japanese employees: a cross-sectional study

    OpenAIRE

    Sakuraya, Asuka; Shimazu, Akihito; Eguchi, Hisashi; Kamiyama, Kimika; Hara, Yujiro; Namba, Katsuyuki; Kawakami, Norito

    2017-01-01

    Background Job crafting, an employee-initiated job design/redesign, has become important for employees? well-being. However, most studies on the relationship between job crafting and employees? well-being have been conducted in western countries; thus, it is unclear whether job crafting can be effectively applied to Asian cultures, such as Japan, which emphasizes group harmony. The aim of this study was to examine the cross-sectional associations of self-reported job crafting with work engage...

  4. Malleable Thought: The Role of Craft Thinking in Practice-Led Graphic Design

    Science.gov (United States)

    Ings, Welby

    2015-01-01

    This article considers the potential of craft processes as creative engagements in graphic design research. It initially discusses the uneasy history of craft within the discipline, then draws upon case studies undertaken by three established designers who, in their postgraduate theses, engaged with craft as a process of thinking. In doing so, the…

  5. 46 CFR 199.220 - Survival craft and rescue boat embarkation arrangements.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft and rescue boat embarkation arrangements... APPLIANCES AND ARRANGEMENTS LIFESAVING SYSTEMS FOR CERTAIN INSPECTED VESSELS Additional Requirements for Passenger Vessels § 199.220 Survival craft and rescue boat embarkation arrangements. (a) Survival craft...

  6. 46 CFR 199.175 - Survival craft and rescue boat equipment.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft and rescue boat equipment. 199.175....175 Survival craft and rescue boat equipment. (a) All lifeboat and rescue boat equipment— (1) Must be... craft or rescue boat; or (iii) Overload the launching appliance. (b) Each lifeboat, rigid liferaft, and...

  7. 47 CFR 80.271 - Technical requirements for portable survival craft radiotelephone transceivers.

    Science.gov (United States)

    2010-10-01

    ... craft radiotelephone transceivers. 80.271 Section 80.271 Telecommunication FEDERAL COMMUNICATIONS... Authorization for Compulsory Ships § 80.271 Technical requirements for portable survival craft radiotelephone transceivers. (a) Portable survival craft radiotelephone transceivers must comply with the following: (1) The...

  8. 46 CFR 199.110 - Survival craft muster and embarkation arrangements.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft muster and embarkation arrangements. 199... § 199.110 Survival craft muster and embarkation arrangements. (a) Each muster station must have... emergency source of electrical power. (e) Each davit-launched and free-fall survival craft muster station...

  9. 33 CFR 149.313 - How must survival craft be arranged?

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false How must survival craft be... Equipment Manned Deepwater Port Requirements § 149.313 How must survival craft be arranged? The operator must arrange survival craft so that they meet the requirements of 46 CFR 108.525 (a) and § 108.530 and...

  10. 46 CFR 108.550 - Survival craft launching and recovery arrangements: General.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Survival craft launching and recovery arrangements...-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Lifesaving Equipment § 108.550 Survival craft.... (c) Each survival craft must be arranged to clear each leg, column, footing, brace, mat, and each...

  11. 46 CFR 180.206 - Survival craft-vessels operating on Great Lakes routes.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft-vessels operating on Great Lakes routes... Craft § 180.206 Survival craft—vessels operating on Great Lakes routes. (a) Except as allowed by... with the survival craft required by § 180.205 (a) through (e), as appropriate. (b) Each vessel...

  12. 46 CFR 199.150 - Survival craft launching and recovery arrangements; general.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft launching and recovery arrangements... Vessels § 199.150 Survival craft launching and recovery arrangements; general. (a)(1) Each launching...) Unless expressly provided otherwise in this part, each survival craft must be provided with a launching...

  13. 26 CFR 1.861-16 - Income from certain craft first leased after December 28, 1980.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Income from certain craft first leased after... the United States § 1.861-16 Income from certain craft first leased after December 28, 1980. (a) General rule. If a taxpayer— (1) Owns a qualified craft (as defined in paragraph (b) of this section). (2...

  14. 76 FR 38153 - California State Nonroad Engine Pollution Control Standards; Commercial Harbor Craft Regulations...

    Science.gov (United States)

    2011-06-29

    ... Standards; Commercial Harbor Craft Regulations; Opportunity for Public Hearing and Comment AGENCY... engines on commercial harbor craft. CARB has requested that EPA issue a new authorization under [email protected] . SUPPLEMENTARY INFORMATION: I. California's Commercial Harbor Craft Regulations In a...

  15. 46 CFR 133.110 - Survival craft muster and embarkation arrangements.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Survival craft muster and embarkation arrangements. 133... VESSELS LIFESAVING SYSTEMS Requirements for All OSVs § 133.110 Survival craft muster and embarkation... lighting supplied from the emergency source of electrical power. (e) Each davit-launched survival craft...

  16. 46 CFR 109.323 - Manning of survival craft and supervision.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Manning of survival craft and supervision. 109.323... DRILLING UNITS OPERATIONS Operation and Stowage of Safety Equipment § 109.323 Manning of survival craft and supervision. (a) There must be a sufficient number of trained persons on board the survival craft for...

  17. 46 CFR 180.205 - Survival craft-vessels operating on limited coastwise routes.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft-vessels operating on limited coastwise... Craft § 180.205 Survival craft—vessels operating on limited coastwise routes. (a) Except as allowed by... survival craft required by § 180.204(d). (e) Each vessel certificated to operate on a limited coastwise...

  18. 33 CFR 149.305 - What are the survival craft requirements for temporary personnel?

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false What are the survival craft... EQUIPMENT Lifesaving Equipment Manned Deepwater Port Requirements § 149.305 What are the survival craft... complement exceeds the capacity of the survival craft required under § 149.304 of this subpart, the port must...

  19. 46 CFR 199.100 - Manning of survival craft and supervision.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Manning of survival craft and supervision. 199.100....100 Manning of survival craft and supervision. (a) There must be a sufficient number of trained... craft and launching arrangements required for abandonment by the total number of persons on board. (c...

  20. 46 CFR 199.245 - Survival craft embarkation and launching arrangements.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft embarkation and launching arrangements... Passenger Vessels § 199.245 Survival craft embarkation and launching arrangements. (a) Each davit-launched liferaft must be arranged to be rapidly boarded by its full complement of persons. (b) All survival craft...

  1. 46 CFR 199.280 - Survival craft embarkation and launching arrangements.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft embarkation and launching arrangements... Cargo Vessels § 199.280 Survival craft embarkation and launching arrangements. (a) Each lifeboat must be.... (d) All survival craft required for abandonment by the total number of persons on board must be...

  2. 46 CFR 133.150 - Survival craft launching and recovery arrangements: General.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Survival craft launching and recovery arrangements...) OFFSHORE SUPPLY VESSELS LIFESAVING SYSTEMS Requirements for All OSVs § 133.150 Survival craft launching and recovery arrangements: General. (a) All survival craft required for abandonment by the total number of...

  3. 46 CFR 180.207 - Survival craft-vessels operating on lakes, bays, and sounds routes.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft-vessels operating on lakes, bays, and... Survival Craft § 180.207 Survival craft—vessels operating on lakes, bays, and sounds routes. (a) Except as... warm water is not required to carry survival craft. (d) A vessel certificated to operate on lakes, bays...

  4. 46 CFR 117.202 - Survival craft-vessels operating on oceans routes.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Survival craft-vessels operating on oceans routes. 117... LIFESAVING EQUIPMENT AND ARRANGEMENTS Number and Type of Survival Craft § 117.202 Survival craft—vessels... number of overnight persons allowed, the survival craft requirements contained in paragraph (e) of this...

  5. 46 CFR 117.208 - Survival craft-vessels operating on rivers routes.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Survival craft-vessels operating on rivers routes. 117... LIFESAVING EQUIPMENT AND ARRANGEMENTS Number and Type of Survival Craft § 117.208 Survival craft—vessels... vessel certificated to operate on a rivers route in warm water is not required to carry survival craft...

  6. Valuing Craftsmanship: In particular the crafting of Chinese porcelain and Dutch Delft Blue

    NARCIS (Netherlands)

    L. Jiang (Lili)

    2018-01-01

    markdownabstract“How important are crafts for a society?” When a conventional economist gets the question, the answer is most likely about the prices of craft products, the income of craftspeople, and the contribution that the crafts sector makes to GDP. This thesis gives another answer. Applying

  7. Mars Ascent Vehicle-Propellant Aging

    Science.gov (United States)

    Dankanich, John; Rousseau, Jeremy; Williams, Jacob

    2015-01-01

    This project is to develop and test a new propellant formulation specifically for the Mars Ascent Vehicle (MAV) for the robotic Mars Sample Return mission. The project was initiated under the Planetary Sciences Division In-Space Propulsion Technology (ISPT) program and is continuing under the Mars Exploration Program. The two-stage, solid motor-based MAV has been the leading MAV solution for more than a decade. Additional studies show promise for alternative technologies including hybrid and bipropellant options, but the solid motor design has significant propellant density advantages well suited for physical constraints imposed while using the SkyCrane descent stage. The solid motor concept has lower specific impulse (Isp) than alternatives, but if the first stage and payload remain sufficiently small, the two-stage solid MAV represents a potential low risk approach to meet the mission needs. As the need date for the MAV slips, opportunities exist to advance technology with high on-ramp potential. The baseline propellant for the MAV is currently the carboxyl terminated polybutadiene (CTPB) based formulation TP-H-3062 due to its advantageous low temperature mechanical properties and flight heritage. However, the flight heritage is limited and outside the environments, the MAV must endure. The ISPT program competed a propellant formulation project with industry and selected ATK to develop a new propellant formulation specifically for the MAV application. Working with ATK, a large number of propellant formulations were assessed to either increase performance of a CTPB propellant or improve the low temperature mechanical properties of a hydroxyl terminated polybutadiene (HTPB) propellant. Both propellants demonstrated potential to increase performance over heritage options, but an HTPB propellant formulation, TP-H-3544, was selected for production and testing. The test plan includes propellant aging first at high vacuum conditions, representative of the Mars transit

  8. New Delivery Systems and Propellants

    Directory of Open Access Journals (Sweden)

    Myrna Dolovich

    1999-01-01

    Full Text Available The removal of chlorofluorocarbon (CFC propellants from industrial and household products has been agreed to by over 165 countires of which more than 135 are developing countries. The timetable for this process is outlined in the Montreal Protocol on Substances that Deplete the Ozone Layer document and in several subsequent amendments. Pressured metered dose inhalers (pMDIs for medical use have been granted temporary exemptions until replacement formulations, providing the same medication via the same route, and with the same efficacy and safety profiles, are approved for human use. Hydrofluoroalkanes (HFAs are the alternative propellants for CFCs-12 and -114. Their potential for damage to the ozone layer is nonexistent, and while they are greenhouse gases, their global warming potential is a fraction (one-tenth of that of CFCs. Replacement formulations for almost all inhalant respiratory medications have been or are being produced and tested; in Canada, it is anticipated that the transition to these HFA or CFC-free pMDIs will be complete by the year 2005. Initially, an HFA pMDI was to be equivalent to the CFC pMDI being replaced, in terms of aerosol properties and effective clinical dose. However, this will not necessarily be the situation, particularly for some corticosteroid products. Currently, only one CFC-free formulation is available in Canada – Airomir, a HFA salbutamol pMDI. This paper discusses the in vitro aerosol characteristics, in vivo deposition and clinical data for several HFA pMDIs for which there are data available in the literature. Alternative delivery systems to the pMDI, namely, dry powder inhalers and nebulizers, are briefly reviewed.

  9. D Digital Simulation of Minnan Temple Architecture CAISSON'S Craft Techniques

    Science.gov (United States)

    Lin, Y. C.; Wu, T. C.; Hsu, M. F.

    2013-07-01

    Caisson is one of the important representations of the Minnan (southern Fujian) temple architecture craft techniques and decorative aesthetics. The special component design and group building method present the architectural thinking and personal characteristics of great carpenters of Minnan temple architecture. In late Qing Dynasty, the appearance and style of caissons of famous temples in Taiwan apparently presented the building techniques of the great carpenters. However, as the years went by, the caisson design and craft techniques were not fully inherited, which has been a great loss of cultural assets. Accordingly, with the caisson of Fulong temple, a work by the well-known great carpenter in Tainan as an example, this study obtained the thinking principles of the original design and the design method at initial period of construction through interview records and the step of redrawing the "Tng-Ko" (traditional design, stakeout and construction tool). We obtained the 3D point cloud model of the caisson of Fulong temple using 3D laser scanning technology, and established the 3D digital model of each component of the caisson. Based on the caisson component procedure obtained from interview records, this study conducted the digital simulation of the caisson component to completely recode and present the caisson design, construction and completion procedure. This model of preserving the craft techniques for Minnan temple caisson by using digital technology makes specific contribution to the heritage of the craft techniques while providing an important reference for the digital preservation of human cultural assets.

  10. Productive and counterproductive job crafting: A daily diary study.

    Science.gov (United States)

    Demerouti, Evangelia; Bakker, Arnold B; Halbesleben, Jonathon R B

    2015-10-01

    The present study aims to uncover the way daily job crafting influences daily job performance (i.e., task performance, altruism, and counterproductive work behavior). Job crafting was conceptualized as "seeking resources," "seeking challenges," and "reducing demands" and viewed as strategies individuals use to optimize their job characteristics. We hypothesized that daily job crafting relates to daily job demands and resources (work pressure and autonomy), which consequently relate to daily work engagement and exhaustion and ultimately to job performance. A sample of 95 employees filled in a quantitative diary for 5 consecutive working days (n occasions = 475). We predicted and found that daily seeking resources was positively associated with daily task performance because daily autonomy and work engagement increased. In contrast, daily reducing demands was detrimental for daily task performance and altruism, because employees lower their daily workload and consequently their engagement and exhaustion, respectively. Only daily seeking challenges was positively (rather than negatively) associated with daily counterproductive behavior. We conclude that employee job crafting can have both beneficial and detrimental effects on job performance. (c) 2015 APA, all rights reserved).

  11. Ghanaian Craft Exporters in the Global Market: Binding and Missing ...

    African Journals Online (AJOL)

    Agribotix GCS 068

    The paper explored the benefits that accrue to Ghanaian craft exporters from subcontracting ties .... viewed as important channels for providing effective and cheaper bases for economic development ... member negatively affect the reputation and cohesion of the group and therefore ...... Unpublished PhD Thesis, University.

  12. Effectiveness of a Volunteer-Led Crafts Group Intervention amongst ...

    African Journals Online (AJOL)

    The purpose of this study was to determine the effectiveness of a volunteer led crafts group intervention (VLCG) as an adjunct to antidepressant medication on mild to moderately depressed women. A quasi-experimental, non-equivalent, control group study was conducted in an urban, psychiatric clinic. Depression was ...

  13. Artisans, Architects, and Apprentices: Valuing the Craft of Teacher Education

    Science.gov (United States)

    Boyd Potter, Rachel

    2016-01-01

    In this article, Boyd Potter describes teacher education faculty as both artisans and architects. As artisans, it is not only their products that enrich us; it is the art of the craft itself that shapes their work. An artisan is valued for the creative endeavor, and not solely the masterpiece. Preparing a quality teacher is not easy work, while…

  14. Bottom Raking Damage to High-Speed Craft

    DEFF Research Database (Denmark)

    Simonsen, Bo Cerup

    1998-01-01

    This paper presents a comparative study of the raking damage to high speed craft (HSC) and conventional ships. The analysis is based on a detailed theoretical model for the raking resistance of an assembled ship bottom structure and on the idea that the impact conditions for various ship types have...

  15. Classroom Teachers' Craft Knowledge of Their Inclusive Practice

    Science.gov (United States)

    Black-Hawkins, Kristine; Florian, Lani

    2012-01-01

    Whilst recent decades have seen significant progress in research on inclusive education, many teachers still feel that the research literature does not fully address their professional concerns about how to enact a policy of inclusion in their classrooms. To help to bridge this gap, we drew on the concept of craft knowledge to undertake a detailed…

  16. Arts, Crafts and Indigenous Industries in Nigeria | Yakubu | Journal ...

    African Journals Online (AJOL)

    The paper is illustrative of the cultural wealth of Nigeria in terms of arts and crafts. It provides a descriptive picture of the various characteristics of the genres in the past and present and in traditional as well as modern Nigerian communities. It functions within religious, intellectual, and socio-economic contexts. Hence ...

  17. Ghanaian Craft Exporters in the Global Market: Binding and Missing ...

    African Journals Online (AJOL)

    The strong positions of buyers and export agents in the craft value chain enable them to apply sanctions to extract compliance from the exporters whereas the weak position of the export vendors implies the lack of sanctioning authority over the rogue artisan subcontractors. The government's promotion programmes could ...

  18. Conceptualizing responsible innovation in craft villages in Vietnam

    NARCIS (Netherlands)

    Voeten, J.; de Haan, J.A.C.; Roome, N.; de Groot, G.A.; Nguyen Thi, Huong; van den Hoven, J.; Doorn, N.; Swierstra, T.; Koops, B.-J.; Romijn, H.

    2014-01-01

    Previous research by the authors has explored small-scale innovations in poor craft producers’ clusters in villages in the Red River Delta in northern Vietnam. Although these innovations resulted in value creation and increased incomes, they also often gave rise to negative environmental or social

  19. Transferring PSM craft skills in a 2 hour session

    NARCIS (Netherlands)

    Zijderveld, E.J.A. van; Morill, N.; Shaw, D.; Belton, V.; Harvey, P.; Rouwette, E.

    2007-01-01

    Many of those involved in the Problem Structuring Methods (PSM) community have commented on the struggle that novices face in building the craft skills associated with conducting a PSM intervention. As part of this year's Operational Research Society Conference, we have three 2-hour practical

  20. Beyond Talent: John Irving and the Passionate Craft of Creativity.

    Science.gov (United States)

    Amabile, Teresa M.

    2001-01-01

    Uses the thoughts and work of novelist John Irving to illustrate the prominence of non-talent components in the componential model of creativity, explaining that raw talent, clever imagination, and a creative personality are insufficient to ensure creative success and that hard work and love of a craft (intrinsic motivation) are at least as…

  1. Reading the Writer's Craft: The Hemingway Short Stories

    Science.gov (United States)

    Garrigues, Lisa

    2004-01-01

    The high school students who spent five weeks studying the style and craft of Ernest Hemingway experienced the power and plus points of apprenticeships. Several assignments that helped the high school juniors to analyze Hemingway's work on short stories and learn from this master craftsman are presented.

  2. Robust formation control of marine surface craft using Lagrange multipliers

    DEFF Research Database (Denmark)

    Ihle, Ivar-Andre F.; Jouffroy, Jerome; Fossen, Thor I.

    2006-01-01

    This paper presents a formation modelling scheme based on a set of inter-body constraint functions and Lagrangian multipliers. Formation control for a °eet of marine craft is achieved by stabilizing the auxiliary constraints such that the desired formation con¯guration appears. In the proposed fr...

  3. The Validity of the School Assessment in the Craft Subject

    Directory of Open Access Journals (Sweden)

    Antti Hilmola

    2016-06-01

    Full Text Available In this research project, the validity of the school assessment is examined in the craft subject in Finland’s basic education. The criteria for the school assessment are based on the Finnish Na-tional Core Curriculum (FNCC in which the idea of the Entire Craft (EC is highlighted. How-ever, the discussion as to whether or not the school practice is based on the idea of EC, or whether the teachers are still focused on the technical details of products in reflecting on the pupils’ tool-handling skills, is still an ongoing debate. Learner-centred learning is implicated in EC since the pupils are expected to set goals for the implementation of their own ideating, plan-ning and constructing. And, finally, in such a process, the self-reflection of the implemented out-comes against the goals will take place.  Altogether 73 craft teachers from 59 upper level schools participated in this research project. The pupils’ (N = 982 success was assessed during an EC period using the indicator validated by the previous nation-wide evaluation by the Finn-ish National Board of Education (FNBE. Since the valid school assessment was expected to reflect the success in the Entire Craft Assessment Period (ECAP, the outcomes were assessed against the criteria of the FNCC and compared to the pupils’ school scores. The data was ana-lysed using the Linear Regression Analysis (Enter Method. The central observation was that the pupils’ success in the criteria of the EC do not reflect the 7th grade school scores, in all re-spects. Moreover, the pupils’ success does not reflect the 6th grade school scores. The instruc-tions and supplementary education of the FNCC criteria are needed for craft teachers, especial-ly for class teachers at the lower level. In Finland, also the craft subject is taught by the class teachers at the lower level while, at the upper level, the subject teachers take their place. Ac-cording to the new FNCC, the number of class lessons will be

  4. A Novel Method for Borehole Blockage Removal and Experimental Study on a Hydraulic Self-Propelled Nozzle in Underground Coal Mines

    Directory of Open Access Journals (Sweden)

    Zhaolong Ge

    2016-08-01

    Full Text Available When coal bed methane (CBM drainage boreholes cross fractured, soft, or water-swelling strata, they collapse and block frequently. Borehole blockages result in a rapid decrease in CBM extraction ability, which leads to a reduction in CBM output and threatens coal mine safety production. To solve these problems, a novel method that uses a self-propelled water-jet nozzle to dredge blocked boreholes in coal seams has been proposed on the basis of the existing technology. Based on a theoretical analysis of the reason for borehole caving and the theory of blockage removal, we optimized the nozzle inlet pressure and selected an appropriate high-pressure resin pipe. A field experiment on the blockage removal of blocked CBM drainage boreholes using the proposed method was run in the Fengchun coal mine, Qijiang, Chongqing, southwest China. In this field trial, the time spent to unblock a borehole varied between 18.52 and 34.98 min, which is much shorter than using a drilling rig. After blockage removal, the average pure volume of the methane drainage of a single borehole was increased from 0.03 L/min to ~1.91–7.30 L/min, and the methane drainage concentration of a single borehole increased from 5% to ~44%–85%. The extraction effect increased significantly.

  5. Energy coefficients for a propeller series

    DEFF Research Database (Denmark)

    Olsen, Anders Smærup

    2004-01-01

    The efficiency for a propeller is calculated by energy coefficients. These coefficients are related to four types of losses, i.e. the axial, the rotational, the frictional, and the finite blade number loss, and one gain, i.e. the axial gain. The energy coefficients are derived by use...... of the potential theory with the propeller modelled as an actuator disk. The efficiency based on the energy coefficients is calculated for a propeller series. The results show a good agreement between the efficiency based on the energy coefficients and the efficiency obtained by a vortex-lattice method....

  6. Noise from Two-Blade Propellers

    Science.gov (United States)

    Stowell, E Z; Deming, A F

    1936-01-01

    The two-blade propeller, one of the most powerful sources of sound known, has been studied with the view of obtaining fundamental information concerning the noise emission. In order to eliminate engine noise, the propeller was mounted on an electric motor. A microphone was used to pick up the sound whose characteristics were studied electrically. The distribution of noise throughout the frequency range, as well as the spatial distribution about the propeller, was studied. The results are given in the form of polar diagrams. An appendix of common acoustical terms is included.

  7. Experimental Research on Air Propellers III

    Science.gov (United States)

    Durand, W F; Lesley, E P

    1920-01-01

    Report presents the results of wind tunnel tests of propellers that examined the influence of the following characteristics: (1) nominal pitch ratio 1.3 combined with a certain number of the more common or standard forms and proportions; (2) driving face slightly rounded or convex; (3) change in the location of the maximum thickness ordinate of the blade section; (4) pushing forward the leading edge of the blade, thus giving a rounded convex surface on the leading side of the driving face. (5) a series of values for the constant "angle of attack" in forming propellers with radially increasing pitch. In accordance with these purposes tests were carried out on 28 propellers.

  8. Shuttle APS propellant thermal conditioner study

    Science.gov (United States)

    Pearson, W. E.

    1971-01-01

    A study program was performed to allow selection of thermal conditioner assemblies for superheating O2 and H2 at supercritical pressures. The application was the auxiliary propulsion system (APS) for the space shuttle vehicle. The O2/H2 APS propellant feed system included propellant conditioners, of which the thermal conditioner assemblies were a part. Cryogens, pumped to pressures above critical, were directed to the thermal conditioner assembly included: (1) a gas generator assembly with ignition system and bipropellant valves, which burned superheated O2 and H2 at rich conditions; (2) a heat exchanger assembly for thermal conditioning of the cryogenic propellant; and (3) a dump nozzle for heat exchanger exhaust.

  9. Job crafting in schools for special education: A qualitative analysis [Job crafting in het speciaal onderwijs: Een kwalitatieve analyse

    NARCIS (Netherlands)

    Wingerden, J. van; Derks, D.; Bakker, A.B.; Dorenbosch, L.

    2013-01-01

    In this article we discuss the design and qualitative (process) evaluation of a job crafting intervention among employees at three Dutch schools for special education. In a period of 1.5 months, fifty employees participated in a group-based training intervention that addressed individual's job

  10. 14 CFR 35.23 - Propeller control system.

    Science.gov (United States)

    2010-01-01

    ... propeller effect under the intended operating conditions. (4) The failure or corruption of data or signals... corruption of airplane-supplied data does not result in hazardous propeller effects. (e) The propeller... effect. (2) Failures or malfunctions directly affecting the propeller control system in a typical...

  11. Development and implementation of a propeller test capability for GL-10 "Greased Lightning" propeller design

    Science.gov (United States)

    Duvall, Brian Edward

    Interest in small unmanned aerial vehicles has increased dramatically in recent years. Hybrid vehicles which allow forward flight as a fixed wing aircraft and a true vertical landing capability have always had applications. Management of the available energy and noise associated with electric propeller propulsion systems presents many challenges. NASA Langley has developed the Greased Lightning 10 (GL-10) vertical takeoff, unmanned aerial vehicle with ten individual motors and propellers. All are used for propulsion during takeoff and contribute to acoustic noise pollution which is an identified nuisance to the surrounding users. A propeller test capability was developed to gain an understanding of how the noise can be reduced while meeting minimum thrust requirements. The designed propeller test stand allowed for various commercially available propellers to be tested for potential direct replacement of the current GL-10 propellers and also supported testing of a newly designed propeller provided by the Georgia Institute of Technology. Results from the test program provided insight as to which factors affect the noise as well as performance characteristics. The outcome of the research effort showed that the current GL-10 propeller still represents the best choice of all the candidate propellers tested.

  12. Effect of Propellant Composition to the Temperature Sensitivity of Composite Propellant

    International Nuclear Information System (INIS)

    Aziz, Amir; Mamat, Rizalman; Amin, Makeen; Wan Ali, Wan Khairuddin

    2012-01-01

    The propellant composition is one of several parameter that influencing the temperature sensitivity of composite propellant. In this paper, experimental investigation of temperature sensitivity in burning rate of composite propellant was conducted. Four sets of different propellant compositions had been prepared with the combination of ammonium perchlorate (AP) as an oxidizer, aluminum (Al) as fuel and hydroxy-terminated polybutadiene (HTPB) as fuel and binder. For each mixture, HTPB binder was fixed at 15% and cured with isophorone diisocyanate (IPDI). By varying AP and Al, the effect of oxidizer- fuel mixture ratio (O/F) on the whole propellant can be determined. The propellant strands were manufactured using compression molded method and burnt in a strand burner using wire technique over a range of pressure from 1 atm to 31 atm. The results obtained shows that the temperature sensitivity, a, increases with increasing O/F. Propellant p80 which has O/F ratio of 80/20 gives the highest value of temperature sensitivity which is 1.687. The results shows that the propellant composition has significant effect on the temperature sensitivity of composite propellant

  13. Alternate Propellant Thermal Rocket, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The Alternate Propellant Thermal Rocket (APTR) is a novel concept for propulsion of space exploration or orbit transfer vehicles. APTR propulsion is provided by...

  14. The PROPEL Electrodynamic Tether Demonstration Mission

    Science.gov (United States)

    Bilen, Sven G.; Johnson, C. Les; Wiegmann, Bruce M.; Alexander, Leslie; Gilchrist, Brian E.; Hoyt, Robert P.; Elder, Craig H.; Fuhrhop, Keith P.; Scadera, Michael

    2012-01-01

    The PROPEL ("Propulsion using Electrodynamics") mission will demonstrate the operation of an electrodynamic tether propulsion system in low Earth orbit and advance its technology readiness level for multiple applications. The PROPEL mission has two primary objectives: first, to demonstrate the capability of electrodynamic tether technology to provide robust and safe, near-propellantless propulsion for orbit-raising, de-orbit, plane change, and station keeping, as well as to perform orbital power harvesting and formation flight; and, second, to fully characterize and validate the performance of an integrated electrodynamic tether propulsion system, qualifying it for infusion into future multiple satellite platforms and missions with minimal modification. This paper provides an overview of the PROPEL system and design reference missions; mission goals and required measurements; and ongoing PROPEL mission design efforts.

  15. In-Space Manufacture of Storable Propellants

    Data.gov (United States)

    National Aeronautics and Space Administration — Many deep-space, missions, especially those that return material or crews to near-Earth space, are severely limited by the need to carry propellants and heat shields...

  16. Propeller performance analysis using lifting line theory

    OpenAIRE

    Flood, Kevin M.

    2009-01-01

    CIVINS (Civilian Institutions) Thesis document Approved for public release ; distribution is unlimited Propellers are typically optimized to provide the maximum thrust for the minimum torque at a specific number of revolutions per minute (RPM) at a particular ship speed. This process allows ships to efficiently travel at their design speed. However, it is useful to know how the propeller performs during off-design conditions. This is especially true for naval warships whose missions req...

  17. Propellant selection for ramjets with solid fuel

    Energy Technology Data Exchange (ETDEWEB)

    Schmucker, R H; Lips, H

    1976-03-11

    Ramjet propulsion using solid propellant for post-boost acceleration of missiles exhibits several favorable properties, brought about by heterogeneous combustion. A simplified theory for calculating the performance of possible propellants is presented, and they are classified with respect to maximum fuel-specific impulse. The optimal choice of fuel, from a system standpoint, must consider volume constraints, and defines the requirements for motor geometry.

  18. O activismo estético feminista de Nikki Craft Nikki Craft's aesthetic feminist activism

    Directory of Open Access Journals (Sweden)

    Rui Pedro Fonseca

    2010-12-01

    Full Text Available Uma das condições para que na sociedade sejam alicerçados valores de género misóginos consiste na existência de uma estrutura de produção cultural heterossexual compulsiva, dominante e universalista que estabeleça princípios de representação dos sexos claramente diferenciados, que tendam a favorecer mais o homem em detrimento da mulher. Partimos de um princípio de que a produção da cultura origina processos de reprodução, o que significa, em termos práticos, que a representação de signos, códigos, valores e comportamentos associados aos sexos é potencialmente materializada nas sociedades, por homens e por mulheres. Essa tem sido uma batalha levada a cabo por muitas mulheres a partir da segunda vaga do movimento feminista, nomeadamente pela ala mais radical, que tem procurado reivindicar novos paradigmas no que diz respeito às convenções culturais de género. O que propomos neste estudo é analisar algumas das campanhas levadas a cabo por Nikki Craft, uma feminista radical norte-americana que viria a organizar e/ou a protagonizar nos anos 1970 e 1980 vários protestos em espaços públicos de algumas cidades dos Estados Unidos. Neste estudo procuramos clarificar as motivações e as estratégias levadas a cabo por essa feminista, cujos activismos incidiram contra algumas das estruturas culturais (campo da arte, instituições da beleza e indústria pornográfica legitimadoras de representações desencadeadoras de prejuízos para a mulherOne of the conditions for misogynic genders to be settled in society consists on the existence of a compulsive dominant and universal heterosexual cultural production, which establishes clearly differentiated representation principles of both sexes. These representation principles tend to favour more the man, disregarding the woman. We consider that culture production gives origin to reproduction processes, which means that, in practical terms, the representation of signs, codes, values

  19. An Electrosurgical Endoknife with a Water-Jet Function (Flushknife Proves Its Merits in Colorectal Endoscopic Submucosal Dissection Especially for the Cases Which Should Be Removed En Bloc

    Directory of Open Access Journals (Sweden)

    Yoji Takeuchi

    2013-01-01

    Full Text Available Background. Previously, we reported that the Flushknife (electrosurgical endoknife with a water-jet function could reduce the operation time of colorectal endoscopic submucosal dissection (ESD however, suitable situation for the Flushknife was obscure. This subgroup analysis of a prospective randomized controlled trial was aimed to investigate the suitable situation for the Flushknife. Methods. A total of 48 superficial colorectal neoplasms that underwent ESD using either the Flexknife or the Flushknife in a referral center were enrolled. The differences of operation time between the Flexknife and the Flushknife groups in each subgroup (tumor size, location, and macroscopic type were analyzed. Results. Median (95% CI operation time calculated using survival curves was significantly shorter in the Flushknife group than in the Flexknife group (55.5 min [41, 78] versus 74.0 [57, 90] min; , Hazard Ratio HR: 0.53; 95% CI (0.29–0.97. In particular, the HR in patients with laterally spreading tumors-nongranular type (LST-NG in the Flushknife group was significantly smaller than in the Flexknife group (HR: 0.1650.17; 95% CI (0.04–0.66. There was a trend of decreasing HRs according to larger lesion size. Conclusions. The Flushknife proved its merits in colorectal ESD especially for the lesions which should be removed en bloc (LST-NG and large lesion.

  20. HMX based enhanced energy LOVA gun propellant

    Energy Technology Data Exchange (ETDEWEB)

    Sanghavi, R.R. [High Energy Materials Research Laboratory, Pune 411021 (India)]. E-mail: sanghavirr@yahoo.co.uk; Kamale, P.J. [High Energy Materials Research Laboratory, Pune 411021 (India); Shaikh, M.A.R. [High Energy Materials Research Laboratory, Pune 411021 (India); Shelar, S.D. [High Energy Materials Research Laboratory, Pune 411021 (India); Kumar, K. Sunil [High Energy Materials Research Laboratory, Pune 411021 (India); Singh, Amarjit [High Energy Materials Research Laboratory, Pune 411021 (India)

    2007-05-08

    Efforts to develop gun propellants with low vulnerability have recently been focused on enhancing the energy with a further improvement in its sensitivity characteristics. These propellants not only prevent catastrophic disasters due to unplanned initiation of currently used gun propellants (based on nitrate esters) but also realize enhanced energy levels to increase the muzzle velocity of the projectiles. Now, in order to replace nitroglycerine, which is highly sensitive to friction and impact, nitramines meet the requirements as they offer superior energy due to positive heat of formation, typical stoichiometry with higher decomposition temperatures and also owing to negative oxygen balance are less sensitive than stoichiometrically balanced NG. RDX has been widely reported for use in LOVA propellant. In this paper we have made an effort to present the work on scantily reported nitramine HMX based LOVA gun propellant while incorporating energetic plasticizer glycidyl azide polymer to enhance the energy level. HMX is known to be thermally stable at higher temperature than RDX and also proved to be less vulnerable to small scale shaped charge jet attack as its decomposition temperature is 270 deg. C. HMX also offers improved impulse due to its superior heat of formation (+17 kcal/mol) as compared to RDX (+14 kcal/mol). It has also been reported that a break point will not appear until 35,000 psi for propellant comprising of 5 {mu}m HMX. Since no work has been reported in open literature regarding replacement of RDX by HMX, the present studies were carried out.

  1. Propeller installation effects on turboprop aircraft acoustics

    Science.gov (United States)

    Chirico, Giulia; Barakos, George N.; Bown, Nicholas

    2018-06-01

    Propeller installation options for a twin-engined turboprop aircraft are evaluated at cruise conditions, aiming to identify the quieter configuration. Computational fluid dynamics is used to investigate the near-field acoustics and transfer functions are employed to estimate the interior cabin noise. Co-rotating and counter-rotating installation options are compared. The effect of propeller synchrophasing is also considered. The employed method captures the complexity of the acoustic field generated by the interactions of the propeller sound fields among each other and with the airframe, showing also the importance of simulating the whole problem to predict the actual noise on a flying aircraft. Marked differences among the various layouts are observed. The counter-rotating top-in option appears the best in terms of acoustics, the top-out propeller rotation leading to louder noise because of inflow conditions and the occurrence of constructive acoustic interferences. Synchrophasing is shown to be beneficial for co-rotating propellers, specially regarding the interior noise, because of favorable effects in the interaction between the propeller direct sound field and the noise due to the airframe. An angle closer to the maximum relative blade shift was found to be the best choice, yielding, however, higher sound levels than those provided by the counter-rotating top-in layout.

  2. Evidence of Validity of the Job Crafting Behaviors Scale

    Directory of Open Access Journals (Sweden)

    Renata Silva de Carvalho Chinelato

    2015-12-01

    Full Text Available AbstractJob crafting behavior refers to the changes made by workers in their job context for adjusting their activities to their preferences. We sought to adapt and collect validity evidences of the Job Crafting Behaviors Scale for the Brazilian context, in a sample of 491 workers, with a mean age of 26.7 years. Factor analysis revealed that the final instrument consisted of three dimensions (increasing structural job resources, increasing social job resources, increasing challenging job demands, which showed good internal consistency indexes. These dimensions showed low or moderate correlations with work engagement, positive psychological capital, positive job affect, and in-role performance. The scale showed evidence of validity, the use of which is recommended for future research on the changes that people make in their jobs.

  3. Hypnobirth within the NHS: time to ditch the parent craft?

    Science.gov (United States)

    Gavin-Jones, Teri

    2016-05-01

    Antenatal education within the National Health Service (NHS) is a service in decline within some hospital trusts. Classes on offer are being moved into online formats or discontinued completely. Whilst research into antenatal education remains limited, what is known is that good birth preparation is of value. "Participative preparation for childbirth can enhance women's overall satisfaction with the childbirth experience" (Schrader McMillan et al 2009: 49). There are pockets of excellent antenatal education within the NHS, but no system for regulating the quality and content. Traditional 'parent craft' classes can be oversubscribed, turning what should be a participative group into an audience. Offering good quality antenatal education has the potential to increase normality, improve the birth outcome and the experience of both woman and her birth partner. Is it time to ditch the parent craft and implement dynamic woman-focused education?

  4. Cavitation noise studies on marine propellers

    Science.gov (United States)

    Sharma, S. D.; Mani, K.; Arakeri, V. H.

    1990-04-01

    Experimental observations are described of cavitation inception and noise from five model propellers, three basic and two modified, tested in the open jet section of the Indian Institute of Science high-speed water tunnel facility. Extensive experiments on the three basic propellers of different design, which included visualization of cavitation and measurements of noise, showed that the dominant type of cavitation was in the form of tip vortex cavitation, accompanied by leading edge suction side sheet cavitation in its close vicinity, and the resultant noise depended on parameters such as the advance coefficient, the cavitation number, and the propeller geometry. Of these, advance coefficient was found to have the maximum influence not only on cavitation noise but also on the inception of cavitation. Noise levels and frequencies of spectra obtained from all the three basic propellers at conditions near inception and different advance coefficient values, when plotted in the normalized form as suggested by Blake, resulted in a universal spectrum which would be useful for predicting cavitation noise at prototype scales when a limited extent of cavitation is expected in the same form as observed on the present models. In an attempt to delay the onset of tip vortex cavitation, the blades of two of the three basic propellers were modified by drilling small holes in the tip and leading edge areas. Studies on the modified propellers showed that the effectiveness of the blade modification was apparently stronger at low advance coefficient values and depended on the blade sectional profile. Measurements of cavitation noise indicated that the modification also improved the acoustic performance of the propellers as it resulted in a complete attenuation of the low-frequency spectral peaks, which were prominent with the basic propellers. In addition to the above studies, which were conducted under uniform flow conditions, one of the basic propellers was tested in the simulated

  5. Craft and Conservation: Features of Danish Journalism Culture

    DEFF Research Database (Denmark)

    Schultz, Ida

    This paper presents the field theory of Pierre Bourdieu, discusses how the framework can be used for studying journalism culture, and illustrates the use in a case study of journalism education in Denmark. The first section makes a first attempt to define Journalism Culture as a logic of practice...... of field, capital and habitus to identity craft as a strong capital in the field and conservation as a dominant logic....

  6. Application of CRAFT in two-dimensional NMR data processing.

    Science.gov (United States)

    Krishnamurthy, Krish; Sefler, Andrea M; Russell, David J

    2017-03-01

    Two-dimensional (2D) data are typically truncated in both dimensions, but invariably and severely so in the indirect dimension. These truncated FIDs and/or interferograms are extensively zero filled, and Fourier transformation of such zero-filled data is always preceded by a rapidly decaying apodization function. Hence, the frequency line width in the spectrum (at least parallel to the evolution dimension) is almost always dominated by the apodization function. Such apodization-driven line broadening in the indirect (t 1 ) dimension leads to the lack of clear resolution of cross peaks in the 2D spectrum. Time-domain analysis (i.e. extraction of frequency, amplitudes, line width, and phase parameters directly from the FID, in this case via Bayesian modeling into a tabular format) of NMR data is another approach for spectral resonance characterization and quantification. The recently published complete reduction to amplitude frequency table (CRAFT) technique converts the raw FID data (i.e. time-domain data) into a table of frequencies, amplitudes, decay rate constants, and phases. CRAFT analyses of time-domain data require minimal or no apodization prior to extraction of the four parameters. We used the CRAFT processing approach for the decimation of the interferograms and compared the results from a variety of 2D spectra against conventional processing with and without linear prediction. The results show that use of the CRAFT technique to decimate the t 1 interferograms yields much narrower spectral line width of the resonances, circumventing the loss of resolution due to apodization. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  7. Tracking Porters: Learning the Craft of Techno-Anthropology.

    Science.gov (United States)

    Bruun, Maja Hojer; Krause-Jensen, Jakob; Saltofte, Margit

    2015-01-01

    Anthropology attempts to gain insight into people's experiential life-worlds through long-term fieldwork. The quality of anthropological knowledge production, however, does not depend solely on the duration of the stay in the field, but also on a particular way of seeing social situations. The anthropological perspective is grounded in socio-cultural theory and forged by a distinct relativist or contextualist epistemological stance. The point is to understand events, concepts and phenomena from the insiders' point of view and to show how this view relates to the particular social and cultural context. In this chapter, we argue that although anthropology has its specific methodology - including a myriad of ethnographic data-gathering tools, techniques, analytical approaches and theories - it must first and foremost be understood as a craft. Anthropology as craft requires a specific 'anthropological sensibility' that differs from the standardized procedures of normal science. To establish our points we use an example of problem-based project work conducted by a group of Techno-Anthropology students at Aalborg University, we focus on key aspects of this craft and how the students began to learn it: For two weeks the students followed the work of a group of porters. Drawing on anthropological concepts and research strategies the students gained crucial insights about the potential effects of using tracking technologies in the hospital.

  8. Propeller and inflow vortex interaction : vortex response and impact on the propeller performance

    NARCIS (Netherlands)

    Yang, Y.; Zhou, T; Sciacchitano, A.; Veldhuis, L.L.M.; Eitelberg, G.

    2016-01-01

    The aerodynamic operating conditions of a propeller can include complex situations where vorticity from sources upstream can enter the propeller plane. In general, when the vorticity enters in a concentrated form of a vortex, the interaction between the vortex and blade is referred to as

  9. Thermal Vacuum Test Correlation of a Zero Propellant Load Case Thermal Capacitance Propellant Gauging Analytical Model

    Science.gov (United States)

    Mckim, Stephen A.

    2016-01-01

    This thesis describes the development and correlation of a thermal model that forms the foundation of a thermal capacitance spacecraft propellant load estimator. Specific details of creating the thermal model for the diaphragm propellant tank used on NASA's Magnetospheric Multiscale spacecraft using ANSYS and the correlation process implemented are presented. The thermal model was correlated to within plus or minus 3 degrees Celsius of the thermal vacuum test data, and was determined sufficient to make future propellant predictions on MMS. The model was also found to be relatively sensitive to uncertainties in applied heat flux and mass knowledge of the tank. More work is needed to improve temperature predictions in the upper hemisphere of the propellant tank where predictions were found to be 2 to 2.5 C lower than the test data. A road map for applying the model to predict propellant loads on the actual MMS spacecraft toward its end of life in 2017-2018 is also presented.

  10. Advances in LO2 Propellant Conditioning

    Science.gov (United States)

    Mehta, Gopal; Orth, Michael; Stone, William; Perry, Gretchen; Holt, Kimberly; Suter, John

    1994-01-01

    This paper describes the cryogenic testing and analysis that has recently been completed as part of a multi-year effort to develop a new, more robust and operable LO2 propellant conditioning system. Phase 1 of the program consisted of feasibility demonstrations ot four novel propellant conditioning concepts. A no-bleed, passive propellant conditioning option was shown for the first time to successfully provide desired propellant inlet conditions. The benefits of passive conditioning are reduced operations costs, decreased hardware costs, enhanced operability and increased reliability on future expendable launch vehicles In Phase 2 of the test program, effects of major design parameters were studied and design correlation for future vehicle design were developed. Simultaneously, analytical models were developed and validated. Over 100 tests were conducted with a full-scale feedline using LN2 as the test fluid. A circulation pump provided a range of pressure and flow conditions. The test results showed that the passive propellant conditioning system is insensitive to variations in many of the parameters. The test program provides the validation necessary to incorporate the passive conditioning system into the baseline of future vehicles. Modeling of these systems using computational fluid dynamics seems highly promising.

  11. Heat transfer in heterogeneous propellant combustion systems

    International Nuclear Information System (INIS)

    Brewster, M.Q.

    1992-01-01

    This paper reports that heat transfer plays an important role in several critical areas of heterogeneous, solid-propellant combustion systems. These areas include heat feedback to the propellant surface, heat transfer between burning aluminum droplets and their surroundings, heat transfer to internal insulation systems, and heat transfer to aft-end equipment. Gas conduction dominates heat feedback to the propellant surface in conventional ammonium perchlorate (AP) composite propellants, although particle radiative feedback also plays a significant role in combustion of metalized propellants. Particle radiation plays a dominant role in heat transfer to internal insulation, compared with that of convection. However, conduction by impingement of burning aluminum particles, which has not been extensively studied, may also be significant. Radiative heat loss plays an important role in determining the burning rate of molten aluminum particles due to a highly luminous, oxide particle-laden, detached flame envelope. Radiation by aluminum oxide smoke particles also plays a dominant role in heat transfer from the exhaust plume to aft-end equipment. Uncertainties in aluminum oxide particle-size distribution and optical properties still make it difficult to predict radiative plume heat transfer accurately from first principles

  12. In-Space Propellant Production Using Water

    Science.gov (United States)

    Notardonato, William; Johnson, Wesley; Swanger, Adam; McQuade, William

    2012-01-01

    A new era of space exploration is being planned. Manned exploration architectures under consideration require the long term storage of cryogenic propellants in space, and larger science mission directorate payloads can be delivered using cryogenic propulsion stages. Several architecture studies have shown that in-space cryogenic propulsion depots offer benefits including lower launch costs, smaller launch vehicles, and enhanced mission flexibility. NASA is currently planning a Cryogenic Propellant Storage and Transfer (CPST) technology demonstration mission that will use existing technology to demonstrate long duration storage, acquisition, mass gauging, and transfer of liquid hydrogen in low Earth orbit. This mission will demonstrate key technologies, but the CPST architecture is not designed for optimal mission operations for a true propellant depot. This paper will consider cryogenic propellant depots that are designed for operability. The operability principles considered are reusability, commonality, designing for the unique environment of space, and use of active control systems, both thermal and fluid. After considering these operability principles, a proposed depot architecture will be presented that uses water launch and on orbit electrolysis and liquefaction. This could serve as the first true space factory. Critical technologies needed for this depot architecture, including on orbit electrolysis, zero-g liquefaction and storage, rendezvous and docking, and propellant transfer, will be discussed and a developmental path forward will be presented. Finally, use of the depot to support the NASA Science Mission Directorate exploration goals will be presented.

  13. Heterogeneous propellant internal ballistics: criticism and regeneration

    Science.gov (United States)

    Glick, R. L.

    2011-10-01

    Although heterogeneous propellant and its innately nondeterministic, chemically discrete morphology dominates applications, ballisticcharacterization deterministic time-mean burning rate and acoustic admittance measures' absence of explicit, nondeterministic information requires homogeneous propellant with a smooth, uniformly regressing burning surface: inadequate boundary conditions for heterogeneous propellant grained applications. The past age overcame this dichotomy with one-dimensional (1D) models and empirical knowledge from numerous, adequately supported motor developments and supplementary experiments. However, current cost and risk constraints inhibit this approach. Moreover, its fundamental science approach is more sensitive to incomplete boundary condition information (garbage-in still equals garbage-out) and more is expected. This work critiques this situation and sketches a path forward based on enhanced ballistic and motor characterizations in the workplace and approximate model and apparatus developments mentored by CSAR DNS capabilities (or equivalent).

  14. Design and simulation on the morphing composite propeller (Conference Presentation)

    Science.gov (United States)

    Chen, Fanlong; Li, Qinyu; Liu, Liwu; Lan, Xin; Liu, Yanju; Leng, Jinsong

    2017-04-01

    As one of the most crucial part of the unmanned underwater vehicle (UUV), the composite propeller plays an important role on the UUV's performance. As the composite propeller behaves excellent properties in hydroelastic facet and acoustic suppression, it attracts increasing attentions all over the globe. This paper goes a step further based on this idea, and comes up with a novel concept of "morphing composite propeller" (MCP) to improve the performance of the conventional composite propeller (CCP) to anticipate the improved propeller can perform better to propel the UUV. Based on the new concept, a novel MCP is designed. Each blade of the propeller is assembled with an active rotatable flap (ARF) to change the blade's local camber with flap rotation. Then the transmission mechanism (TM) has been designed and housed in the propeller blade to push the ARF. With the ARF rotating, the UUV can be propelled by different thrusts under certain rotation velocities of the propeller. Based on the design, the Fluent is exploited to analyze the fluid dynamics around the propeller. Finally, based on the design and hydrodynamic analysis, the structural response for the novel morphing composite propeller is calculated. The propeller blade is simplified and layered with composite materials. And the structure response of an MCP is obtained with various rotation angle under the hydrodynamic pressure. This simulation can instruct the design and fabrication techniques of the MCP.

  15. Environmental Support to Amphibious Craft, Patrol Boats, and Coastal Ships: An Annotated Bibliography

    National Research Council Canada - National Science Library

    Bachmann, Charles M; Fusina, Robert A; Nichols, C. R; McDermid, Jack

    2008-01-01

    This annotated bibliography is a selection of citations to books, articles, documents, and data bases highlighting environmental conditions that impact the safety and performance of amphibious craft...

  16. CFD simulation on Kappel propeller with a hull wake field

    DEFF Research Database (Denmark)

    Shin, Keun Woo; Andersen, Poul; Møller Bering, Rasmus

    2013-01-01

    Marine propellers are designed not for the open-water operation, but for the operation behind a hull due to the inhomogeneous hull wake and thrust deduction. The adaptation for the hull wake is important for the propulsive efficiency and cavitation risk especially on single-screw ships. CFD...... simulations for a propeller with a hull model have showed acceptable agreement with a model test result in the thrust and torque (Larsson et al. 2010). In the current work, a measured hull wake is applied to the simulation instead of modelling a hull, because the hull geometry is mostly not available...... for propeller designers and the computational effort can be reduced by excluding the hull. The CFD simulation of a propeller flow with a hull wake is verified in order to use CFD as a propeller design tool. A Kappel propeller, which is an innovative tip-modified propeller, is handled. Kappel propellers...

  17. Process for the leaching of AP from propellant

    Science.gov (United States)

    Shaw, G. C.; Mcintosh, M. J. (Inventor)

    1980-01-01

    A method for the recovery of ammonium perchlorate from waste solid rocket propellant is described wherein shredded particles of the propellant are leached with an aqueous leach solution containing a low concentration of surface active agent while stirring the suspension.

  18. Neural Network Predictions of the 4-Quadrant Wageningen Propeller Series

    National Research Council Canada - National Science Library

    Roddy, Robert F; Hess, David E; Faller, Will

    2006-01-01

    .... This report describes the development of feedforward neural network (FFNN) predictions of four-quadrant thrust and torque behavior for the Wageningen B-Screw Series of propellers and for two Wageningen ducted propeller series...

  19. Innovative Swirl Injector for LOX and Hydrocarbon Propellants, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Gases trapped in the propellant feed lines of space-based rocket engines due to cryogenic propellant boil-off or pressurant ingestion can result in poor combustion...

  20. Propellant Gelation for Green In-Space Propulsion, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Concerns in recent years about the toxicity and safe handling of the storable class of propellants have led to efforts in greener monopropellants and bi-propellants....

  1. Ergonomic Analysis of the Work Condition in Aluminum Crafts Industry

    Science.gov (United States)

    Soewardi, H.; Taufiq, A.; Pradipta, T.

    2017-12-01

    Indonesia has plenty of abundant natural wealth. This natural wealth produces natural materials that can be utilized as a craft product. The craft workers generally still work manually and the work is done repeatedly in one cycle so it is very susceptible to musculoskeletal disorders. Musculoskeletal disorders will cause decrease of worker’s effectiveness and efficiency in completing the task. Thus, this fact has some adverse impact for the company. The purpose of this study is to analyze some task in manufacturing a traditional cooking tool (griddle) which encompasses mold of the griddle, refine of the griddle and the finishing touch by using the Occupational Repetitive Action Index (OCRA index) method. This method consists of high frequency movements, large forces, awkward postures, insufficient resting time and other factor such as vibration. Result of this study shows that in the molding operation, the worker has uncertain and medium risk on right hand in manufacturing small and large size of griddle with OCRA index is 2.5 and 5.3 respectively. In the refining operation the worker has light and medium risk on left hand in manufacturing small and large size with OCRA index is 3.6 and 5.8 using grinding machine and 5.8, 5.2, 6.3 and 5.0 using miser tool. In finishing operation, the worker has high risk on right hand in numbering of code griddle and has medium risk on right hand and medium on left hand in labeling with OCRA index is 9, 6.1 and 6.8 While in assembling operation the worker has no risk. Score that it indicates the risk level of the task in such job. Thus the following actions are to improve the work condition ergonomicly in all operation in alumunium craft.

  2. Ionic liquid propellants: future fuels for space propulsion.

    Science.gov (United States)

    Zhang, Qinghua; Shreeve, Jean'ne M

    2013-11-11

    Use of green propellants is a trend for future space propulsion. Hypergolic ionic liquid propellants, which are environmentally-benign while exhibiting energetic performances comparable to hydrazine, have shown great potential to meet the requirements of developing nontoxic high-performance propellant formulations for space propulsion applications. This Concept article presents a review of recent advances in the field of ionic liquid propellants. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Craft vs. industrial: Habits, attitudes and motivations towards beer consumption in Mexico.

    Science.gov (United States)

    Gómez-Corona, Carlos; Escalona-Buendía, Héctor B; García, Mauricio; Chollet, Sylvie; Valentin, Dominique

    2016-01-01

    Food choices tend to be stable over time; they do not change fast, since consumers tend to act like creatures of habits. However, food habits can evolve, like currently the craft beer category. A change of habits involves a change of perception towards a product. Therefore, what is changing in the perception of beer? Two studies were conducted to address this question. First study was preliminary and aimed at exploring beer consumption habits in Mexico and a better understanding of craft beer representation among beer users. A questionnaire was administrated to 207 consumers in Mexico City during a beer festival. Results showed that respondents could be classified in: industrial beer (41.1%), occasional industrial (24.1%), and craft beer (34.8%) consumers. Craft cluster included mostly 25-35 years old men with high-income level. Among the craft beers cited by respondents from this cluster some are industrial, suggesting that the concept of craft beer might not be well defined, or defined in ideological terms. The second and main study was conducted using consumer ethnographies to understand the motivations and benefits of craft beer consumption. Opposite to industrial, craft beer emerges as an experience-based and symbolic product rather than a utilitarian one. The main motivation for drinking craft beer seems to be the quest of authenticity. Respondents' motivations to drink craft beer are generated by three important factors: desire for more knowledge, new taste experiences, and move away from the mainstream beer consumption. Craft consumers do not drink the product for its functional attributes, they consume it for what it means and as a consequence they build an identity, perceived as more authentic and unique, in comparison to the mainstream industrial beer consumption in Mexico. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Changing of ballistic parameters from aged gun propellants

    NARCIS (Netherlands)

    Klerk, W.P.C. de; Driel, C.A. van

    2003-01-01

    The various properties of an SB and a DB gun propellant were investigated before and after artificial ageing. It was found that the decrease of nitrocellulose (NC) molecular weight, due to ageing of gun propellants, leads to a decrease of the mechanical integrity of the propellant grains. The effect

  5. Burning properties and mechanical integrity of aged gun propellants

    NARCIS (Netherlands)

    Driel, C.A. van; Klerk, W.P.C. de

    2017-01-01

    Conventional gun propellants exhibit the phenomenon of nitrocellulose (NC) decomposition. Besides an effect on thermal stability of propellants, decomposition of NC has an effect on the mechanical integrity of the propellant grains. Enhanced grain fracture may lead to unacceptable changes of the

  6. 14 CFR 25.907 - Propeller vibration and fatigue.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Propeller vibration and fatigue. 25.907... vibration and fatigue. This section does not apply to fixed-pitch wood propellers of conventional design. (a... propeller to show that failure due to fatigue will be avoided throughout the operational life of the...

  7. 14 CFR 23.907 - Propeller vibration and fatigue.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Propeller vibration and fatigue. 23.907... General § 23.907 Propeller vibration and fatigue. This section does not apply to fixed-pitch wood... evaluation of the propeller to show that failure due to fatigue will be avoided throughout the operational...

  8. Design Procedure of 4-Bladed Propeller

    African Journals Online (AJOL)

    PROF. O. E. OSUAGWU

    2013-09-01

    Sep 1, 2013 ... West African Journal of Industrial and Academic Research Vol.8 No.1 September 2013 ..... Number of blades. 5. Taylor's wake friction (w). The speed of ship (Vs), the number of propeller revolution (n), the blade number (Z) and the blade area ratio.... .... moment of inertia of a blade, the approximate.

  9. Spray and Combustion of Gelled Hypergolic Propellants

    Science.gov (United States)

    2014-10-20

    moisture absorption on the fumed silica surface correlates directly to the ambient humidity , and can reach 12% by weight at an atmospheric humidity of...propellant interface, the liquid at the interface can be heated to the homogeneous vapor nucleation temperature rather than the boiling point. At this

  10. Atmospheric surveillance self-propelling device

    International Nuclear Information System (INIS)

    Cartoux, Gerard.

    1980-11-01

    The atmospheric surveillance self-propelling device of the Saclay Nuclear Research Center can, by its conception (autonomy, rapid put into service, multiplicity of sampling and measurements), be used for all kind of measuring campains: pollution radioactive or not, routine or accidental situation, technical and logistic support and as a coordination or investigation vehicle [fr

  11. 75 FR 12148 - Airworthiness Directives; Ontic Engineering and Manufacturing, Inc. Propeller Governors, Part...

    Science.gov (United States)

    2010-03-15

    ... propeller pitch by regulating oil pressure to the propeller pitch change mechanism. Changes in governor oil..., the propeller governor cannot control oil pressure to the propeller pitch control mechanism. This... proposing this AD to prevent loss of propeller pitch control, damage to the propeller governor, and internal...

  12. Space Transportation Infrastructure Supported By Propellant Depots

    Science.gov (United States)

    Smitherman, David; Woodcock, Gordon

    2012-01-01

    A space transportation infrastructure is described that utilizes propellant depot servicing platforms to support all foreseeable missions in the Earth-Moon vicinity and deep space out to Mars. The infrastructure utilizes current expendable launch vehicle (ELV) systems such as the Delta IV Heavy, Atlas V, and Falcon 9, for all crew, cargo, and propellant launches to orbit. Propellant launches are made to Low-Earth-Orbit (LEO) Depot and an Earth-Moon Lagrange Point 1 (L1) Depot to support a new reusable in-space transportation vehicles. The LEO Depot supports missions to Geosynchronous Earth Orbit (GEO) for satellite servicing and to L1 for L1 Depot missions. The L1 Depot supports Lunar, Earth-Sun L2 (ESL2), Asteroid and Mars Missions. New vehicle design concepts are presented that can be launched on current 5 meter diameter ELV systems. These new reusable vehicle concepts include a Crew Transfer Vehicle (CTV) for crew transportation between the LEO Depot, L1 Depot and missions beyond L1; a new reusable lunar lander for crew transportation between the L1 Depot and the lunar surface; and Mars orbital Depot are based on International Space Station (ISS) heritage hardware. Data provided includes the number of launches required for each mission utilizing current ELV systems (Delta IV Heavy or equivalent) and the approximate vehicle masses and propellant requirements. Also included is a discussion on affordability with ideas on technologies that could reduce the number of launches required and thoughts on how this infrastructure include competitive bidding for ELV flights and propellant services, developments of new reusable in-space vehicles and development of a multiuse infrastructure that can support many government and commercial missions simultaneously.

  13. Propellant Slosh Force and Mass Measurement

    Directory of Open Access Journals (Sweden)

    Andrew Hunt

    2018-01-01

    Full Text Available We have used electrical capacitance tomography (ECT to instrument a demonstration tank containing kerosene and have successfully demonstrated that ECT can, in real time, (i measure propellant mass to better than 1% of total in a range of gravity fields, (ii image propellant distribution, and (iii accurately track propellant centre of mass (CoM. We have shown that the ability to track CoM enables the determination of slosh forces, and we argue that this will result in disruptive changes in a propellant tank design and use in a spacecraft. Ground testing together with real-time slosh force data will allow an improved tank design to minimize and mitigate slosh forces, while at the same time keeping the tank mass to a minimum. Fully instrumented Smart Tanks will be able to provide force vector inputs to a spacecraft inertial navigation system; this in turn will (i eliminate or reduce navigational errors, (ii reduce wait time for uncertain slosh settling, since actual slosh forces will be known, and (iii simplify slosh control hardware, hence reducing overall mass. ECT may be well suited to space borne liquid measurement applications. Measurements are independent of and unaffected by orientation or levels of g. The electronics and sensor arrays can be low in mass, and critically, the technique does not dissipate heat into the propellant, which makes it intrinsically safe and suitable for cryogenic liquids. Because of the limitations of operating in earth-bound gravity, it has not been possible to check the exact numerical accuracy of the slosh force acting on the vessel. We are therefore in the process of undertaking a further project to (i build a prototype integrated “Smart Tank for Space”, (ii undertake slosh tests in zero or microgravity, (iii develop the system for commercial ground testing, and (iv qualify ECT for use in space.

  14. JEAN CLAUDE RENARD: (POETRY AS CRAFT OF TRANSPARENCY

    Directory of Open Access Journals (Sweden)

    María del Sagrario Rollán

    2015-04-01

    Full Text Available The work of Jean-Claude Renard (Toulon 1922- Paris 2002 appears from the beginning marked by the metaphor of the journey - Songs for land lost (1947, and the craft of transparency. The poet begins the journey - that originates in the experience of death and destruction of a world shaken by the war, with a word that transcends the nonsense, and calls for “the country where forgiveness is / and are childhoods “a word that is built in search of human spaces and anticipates them. The adventure through the exercise of Solitude (1951, requirement beyond itself, a kind of internal and painful split: “I am separated from my heart,” releasing it, in turn, to the knowledge of the world and the gift that transfigures. The metamorphosis of the World (1951 takes place in the act of writing itself, for in him a knowledge of the essential reality is given, from which the party of pure celebrated say, “Oh breathing started / in the center of the loaf and snow “. Poetry as craft of transparency J.C. Renard develops in Un autre parole  (1981, prose poetry admirably clarifies its internal relations with theology and mysticism. The poet moves beyond “ailleurs” to a previous or future place of reconciliation and love letters between beings: “One happy pasture / leads above child / each wisdom to your name / and every love your body.”

  15. Inshore craft traditional working vessels of the british isles

    CERN Document Server

    Greenhill, Basil

    2013-01-01

    This comprehensive reference work describes and illustrates some 200 types of inshore craft that once fished and traded, under oar and sail, around the coasts of the British Isles. The types are arranged by coastal area and each is described in terms of its shape and design, fitness for location and purpose, build, evolution and geographical distribution. Details of dimensions, rig, building materials, seamanship and the survival of examples are given where known, while hundreds of line drawings and photographs show the vessels in their original forms.A team of twelve experts describe all these boat types and, in addition, there are introductions to the main geographic areas outlining the physical environments, fisheries and other uses of the sea that have influenced boat design; maps of all the areas show ports and physical features.At the beginning of the last century sail and oar dominated fisheries and local trade: one hundred years later those craft have all but vanished. This book brings alive for marit...

  16. Overview of craft brewing specificities and potentially associated microbiota.

    Science.gov (United States)

    Rodhouse, Lindsey; Carbonero, Franck

    2017-09-14

    The brewing process differs slightly in craft breweries as compared to industrial breweries, as there are fewer control points. This affects the microbiota of the final product. Beer contains several antimicrobial properties that protect it from pathogens, such as low pH, low oxygen and high carbon dioxide content, and the addition of hops. However, these hurdles have limited power controlling spoilage organisms. Contamination by these organisms can originate in the raw materials, persist in the environment, and be introduced by using flavoring ingredients later in the process. Spoilage is a prominent issue in brewing, and can cause quality degradation resulting in consumer rejection and product waste. For example, lactic acid bacteria are predominately associated with producing a ropy texture and haze, along with producing diacetyl which gives the beer butter flavor notes. Other microorganisms may not affect flavor or aroma, but can retard fermentation by consuming nutrients needed by fermentation yeast. Quality control in craft breweries today relies on culturing methods to detect specific spoilage organisms. Using media can be beneficial for detecting the most common beer spoilers, such as Lactobacillus and Pediococci. However, these methods are time consuming with long incubation periods. Molecular methods such as community profiling or high throughput sequencing are better used for identifying entire populations of beer. These methods allow for detection, differentiation, and identification of taxa.

  17. Job crafting and its impact on work engagement and job satisfaction in mining and manufacturing

    NARCIS (Netherlands)

    De Beer, L.T. (Leon T.); M. Tims (Maria); A.B. Bakker (Arnold)

    2016-01-01

    textabstractThe purpose of this study was to investigate job crafting and its relationship with work engagement and job satisfaction within the South African context. This research is important as job crafting has been shown to have a positive influence on employee motivation. A cross-sectional

  18. Crafting qualities in designing QR-coded embroidery and bedtime stories

    NARCIS (Netherlands)

    Kuusk, K.; Wensveen, S.A.G.; Tomico, O.

    2014-01-01

    There is a renewed interest into crafts and what it can mean when integrating new technologies into textiles. This paper proposes to embed craft qualities and sustainable values into designing smart textile projects. Our design iterations QR-Coded Embroidery and Bedtime Stories combine textiles,

  19. The Need for the United States Army to Possess a Landing Craft with Maneuver Capabilities

    Science.gov (United States)

    2015-06-12

    landing craft after the 2004 Indian Ocean tsunami and the 2009 Myanmar cyclone.9 The landing craft enabled the relief effort to bypass partially...requirements for Army aviation . The Need for America’s Amphibious Capability In his thesis, “The Need for the United States of America’s Amphibious

  20. The job crafting intervention: effects on job resources, self-efficacy, and affective well-being

    NARCIS (Netherlands)

    van den Heuvel, M.; Demerouti, E.; Peeters, M.C.W.

    2015-01-01

    This quasi-experimental field study examines the effects of an intervention designed to boost job resources, affective well-being, and self-efficacy via job crafting behaviour. Employees (n = 39) in a Dutch police district received a 1-day training, after which they worked towards self-set crafting

  1. The job crafting intervention : Effects on job resources, self-efficacy, and affective well-being

    NARCIS (Netherlands)

    van den Heuvel, Machteld; Demerouti, Evangelia; Peeters, Maria|info:eu-repo/dai/nl/07487893X

    2015-01-01

    This quasi-experimental field study examines the effects of an intervention designed to boost job resources, affective well-being, and self-efficacy via job crafting behaviour. Employees (n = 39) in a Dutch police district received a 1-day training, after which they worked towards self-set crafting

  2. Microwave-assisted facile and rapid Friedel-Crafts benzoylation of arenes catalysed by bismuth trifluoromethanesulfonate

    DEFF Research Database (Denmark)

    Tran, Phoung Hoang; Hansen, Poul Erik; Pham, Thuy Than

    2014-01-01

    The catalytic activity of metal triflates was investigated in Friedel–Crafts benzoylation under microwave irradiation. Friedel–Crafts benzoylation with benzoyl chloride of a variety of arenes containing electron-rich and electron-poor rings using bismuth triflate under microwave irradiation is de...

  3. A discussion of the necessity of craft education in the 21st century

    Directory of Open Access Journals (Sweden)

    Eva Veeber

    2015-02-01

    Full Text Available Craft education has held a permanent place in Estonian and Finnish schools, although its value and appreciation have changed over time. The aim of the article is to discuss the necessity of craft education in today’s world and its possible impact on the development of children and adolescents. The discussion seeks an interdisciplinary explanation using three perspectives that complement each other. The first describes the challenges of modern society with respect to individual development and schooling. The second deals with Aaron Antonovsky's theory of generalized resistance resources and an individual's possibility to manage in a stressful society. The third addresses the individual as a developing neurological being, along with the effect of learning and practicing motor skills on the human brain. We conclude that crafts is a multidisciplinary phenomenon, and that learning and practicing crafts promotes the comprehension of diversity and challenges in life. Additionally, educational crafts enriches the learning environment, offering opportunities to develop transferable skills that human beings constantly need in society. In addition, crafts provides a balanced way to come to understand the world and one’s role in it, by simultaneously promoting motor and cognitive development and making unique demands on one’s being.Keywords: crafts, craft education, making, sense of coherence, education, embodiment

  4. 46 CFR 180.204 - Survival craft-vessels operating on coastwise routes.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft-vessels operating on coastwise routes. 180.204 Section 180.204 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL... Craft § 180.204 Survival craft—vessels operating on coastwise routes. (a) Except as allowed by paragraph...

  5. 46 CFR 180.202 - Survival craft-vessels operating on oceans routes.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft-vessels operating on oceans routes. 180... VESSELS (UNDER 100 GROSS TONS) LIFESAVING EQUIPMENT AND ARRANGEMENTS Number and Type of Survival Craft § 180.202 Survival craft—vessels operating on oceans routes. (a) Each vessel certificated to operate on...

  6. 46 CFR 117.207 - Survival craft-vessels operating on lakes, bays, and sounds routes.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Survival craft-vessels operating on lakes, bays, and... 49 PASSENGERS LIFESAVING EQUIPMENT AND ARRANGEMENTS Number and Type of Survival Craft § 117.207 Survival craft—vessels operating on lakes, bays, and sounds routes. (a) Each vessel with overnight...

  7. 33 CFR 100.916 - Chris Craft Silver Cup Races, Algonac, MI.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Chris Craft Silver Cup Races, Algonac, MI. 100.916 Section 100.916 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.916 Chris Craft Silver Cup...

  8. Shifting Values: The Promotional Policies of Craft and Industrial Design in Flanders (1980-2001)

    NARCIS (Netherlands)

    Gimeno Martinez, J.C.

    2014-01-01

    This article looks at the shifts in cultural promotion of craft as a result of a particular political conjuncture in the region of Flanders (Belgium). In 1991, as a consequence of Belgian federalization, the promotion policies for craft in Flanders passed from being answerable to the Belgian state

  9. 46 CFR 180.208 - Survival craft-vessels operating on rivers routes.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft-vessels operating on rivers routes. 180... VESSELS (UNDER 100 GROSS TONS) LIFESAVING EQUIPMENT AND ARRANGEMENTS Number and Type of Survival Craft § 180.208 Survival craft—vessels operating on rivers routes. (a) Except as allowed by paragraphs (c), (d...

  10. Design and Craft Education in Iceland, Pedagogical Background and Development: A Literature Review

    Science.gov (United States)

    Olafsson, Brynjar; Thorsteinsson, Gisli

    2009-01-01

    Sloyd pedagogy was introduced towards the close of the 18th century to Icelandic educators. Subsequently craft was established as a specific subject aimed at general education. In the beginning craft was called "school industry," to distinguish it from "home industry" whose aim was to help homes to be self-sufficient for…

  11. "Miss! I'm Done!" Finishing Craft Assignments as a Situated Activity System in Preschool

    Science.gov (United States)

    Deunk, Marjolein; Berenst, Jan; de Glopper, Kees

    2010-01-01

    We describe the Situated Activity System of finishing craft assignments in preschool: the specific, routinized way that child and teacher jointly close the child's craft assignment, employing a specific discourse pattern. We analyzed the interactions of 14 Dutch children between 2.1 and 3.10 years old while they were finishing their craft…

  12. Cultivating Perspectival Acuity: The Value and Cost of Integrating Theory, Craft, Research, and Practice

    Directory of Open Access Journals (Sweden)

    Joe Manganelli

    2016-10-01

    Full Text Available This paper presents reflections on integrating theory, craft, research, and practice to improve the accuracy and resiliency of each. The reflections build toward a set of statements about the value and the cost of integrating theory, craft, research, and practice. Specifically, the authors offer the Privileged Work / Non-Privileged Work Framework and concept of cultivating Perspectival Acuity.

  13. Digitizing Craft: Creative Writing Studies and New Media--A Proposal

    Science.gov (United States)

    Koehler, Adam

    2013-01-01

    This article identifies and examines a digital arm of creative writing studies and organizes that proposal into four categories through which to theorize the "craft" of creative production, each borrowed from Tim Mayers's "(Re)Writing Craft: Composition, Creative Writing, and the Future of English Studies": process, genre, author, and…

  14. Cooking and Hammering: Primary School Pupils' Concepts of Their Craft Skills

    Science.gov (United States)

    Müürsepp, Mare; Kikkull, Andry

    2014-01-01

    The aim of the study is to clear the significance of craft skills for the pupils in age nine and twelve years. More than 200 pupils were asked to define, what are the most important skills for the pupils of their age. The results bring out that category of the skills related to craft subject is of the most presented categories in pupils' self…

  15. Job crafting at the team and individual level: Implications for work engagement and performance

    NARCIS (Netherlands)

    Tims, M.; Bakker, A.B.; Derks, D.; Rhenen, van W.

    2013-01-01

    Previous research suggests that employee job crafting is positively related to job performance through employee work engagement. The present study expands this individual-level perspective to the team level by hypothesizing that team job crafting relates positively to team performance through team

  16. The Influence of Future Time Perspective on Worker Outcomes: The Role of Job Crafting

    NARCIS (Netherlands)

    Kooij, T.A.M.; Tims, M.; Akkermans, J.

    2017-01-01

    This two-wave study aimed to examine future time perspective (FTP) as an antecedent of job crafting, and in turn job crafting as a mediator in associations between FTP and work outcomes. Based on the lifespan socio-emotional selectivity theory, we expected that open-ended and limited FTP would evoke

  17. Workaholism versus work engagement and job crafting : What is the role of self-management strategies?

    NARCIS (Netherlands)

    Zeijen, Marijntje E.L.; Peeters, Maria C.W.; Hakanen, Jari J.

    2018-01-01

    Job crafting refers to the proactive actions employees take to redesign their jobs in order to get a better fit with their competencies, expectations, and wishes. So far, little is known about job crafting's underlying mechanisms. In this study, we examine how two different states of affective

  18. Workaholism versus work engagement and job crafting : What is the role of self-management strategies?

    NARCIS (Netherlands)

    Zeijen, M.; Peeters, M.C.W.; Hakanen, J.

    Job crafting refers to the proactive actions employees take to redesign their jobs in order to get a better fit with their competencies, expectations, and wishes. So far, little is known about job crafting's underlying mechanisms. In this study, we examine how two different states of affective

  19. Report: The New Brunswick Indian Arts and Crafts Association Workshop for Board Members. No. 165.

    Science.gov (United States)

    Goddu, Roland; Nicholas, Darryl

    This is a report on a training session conducted for the board members of the New Brunswick Indian Arts and Crafts Association with the aim of outlining purposes of the Association, and assisting in drawing up plans for a formal administrative structure among arts and crafts organizations. An administrative manual containing terms of reference…

  20. The Development of Indian and Eskimo Art and Crafts in the Far North.

    Science.gov (United States)

    Phillips, R. A. J.; And Others

    The focus of the conference, "The Development of Indian and Eskimo Art and Crafts in the Far North," was the creation of a market for reputable Indian and Eskimo art work on an economically sound basis which would benefit both the native artists and the Canadian economy. Two governmental reports, "Northern Arts and Crafts" and…

  1. The impact of job crafting on job demands, job resources, and well-being

    NARCIS (Netherlands)

    Tims, M.; Bakker, A.B.; Derks, D.

    2013-01-01

    This longitudinal study examined whether employees can impact their own well-being by crafting their job demands and resources. Based on the Job Demands-Resources model, we hypothesized that employee job crafting would have an impact on work engagement, job satisfaction, and burnout through changes

  2. Computer Technology-Integrated Projects Should Not Supplant Craft Projects in Science Education

    Science.gov (United States)

    Klopp, Tabatha J.; Rule, Audrey C.; Schneider, Jean Suchsland; Boody, Robert M.

    2014-01-01

    The current emphasis on computer technology integration and narrowing of the curriculum has displaced arts and crafts. However, the hands-on, concrete nature of craft work in science modeling enables students to understand difficult concepts and to be engaged and motivated while learning spatial, logical, and sequential thinking skills. Analogy…

  3. Development of a Marine Propeller With Nonplanar Lifting Surfaces

    DEFF Research Database (Denmark)

    Andersen, Poul; Friesch, Jürgen; Kappel, Jens J.

    2005-01-01

    The principle of non-planar lifting surfaces is applied to the design of modern aircraft wings to obtain better lift to drag ratios. Whereas a pronounced fin or winglet at the wingtip has been developed for aircraft, the application of the nonplanar principle to marine propellers, dealt...... with in this paper, has led to the KAPPEL propeller with blades curved toward the suction side integrating the fin or winglet into the propeller blade. The combined theoretical, experimental, and practical approach to develop and design marine propellers with nonplanar lifting surfaces has resulted in propellers...

  4. When craft and science collide: Improving therapeutic practices through evidence-based innovations.

    Science.gov (United States)

    Justice, Laura M

    2010-04-01

    Evidence-based practice (EBP) is a model of clinical decision-making that is increasingly being advocated for use in the field of speech-language pathology. With the increased emphasis on scientific evidence as a form of knowledge important to EBP, clinicians may wonder whether their craft-based knowledge (i.e., knowledge derived from theory and practice), remains a legitimate form of knowledge for use in clinician decisions. This article describes forms of knowledge that may be used to address clinical questions, to include both craft and science. Additionally, the steps used when engaging in EBP are described so that clinicians understand when and how craft comes into play. The major premise addressed within this article is that craft is a legitimate form of knowledge and that engagement in EBP requires one to employ craft-based knowledge.

  5. Study of a 30-M Boom For Solar Sail-Craft: Model Extendibility and Control Strategy

    Science.gov (United States)

    Keel, Leehyun

    2005-01-01

    Space travel propelled by solar sails is motivated by the fact that the momentum exchange that occurs when photons are reflected and/or absorbed by a large solar sail generates a small but constant acceleration. This acceleration can induce a constant thrust in very large sails that is sufficient to maintain a polar observing satellite in a constant position relative to the Sun or Earth. For long distance propulsion, square sails (with side length greater than 150 meters) can reach Jupiter in two years and Pluto in less than ten years. Converting such design concepts to real-world systems will require accurate analytical models and model parameters. This requires extensive structural dynamics tests. However, the low mass and high flexibility of large and light weight structures such as solar sails makes them unsuitable for ground testing. As a result, validating analytical models is an extremely difficult problem. On the other hand, a fundamental question can be asked. That is whether an analytical model that represents a small-scale version of a solar-sail boom can be extended to much larger versions of the same boom. To answer this question, we considered a long deployable boom that will be used to support the solar sails of the sail-craft. The length of fully deployed booms of the actual solar sail-craft will exceed 100 meters. However, the test-bed we used in our study is a 30 meter retractable boom at MSFC. We first develop analytical models based on Lagrange s equations and the standard Euler-Bernoulli beam. Then the response of the models will be compared with test data of the 30 meter boom at various deployed lengths. For this stage of study, our analysis was limited to experimental data obtained at 12ft and 18ft deployment lengths. The comparison results are positive but speculative. To observe properly validate the analytic model, experiments at longer deployment lengths, up to the full 30 meter, have been requested. We expect the study to answer the

  6. Investigation on utilization of liquid propellant in ballistic range experiments

    Energy Technology Data Exchange (ETDEWEB)

    Saso, Akihiro; Oba, Shinji; Takayama, Kazuyoshi [Tohoku University, Sendai (Japan)

    1999-10-31

    Experiments were conducted in a ballistic range using a HAN (hydroxylammonium nitrate)-based liquid monopropellant, LP1846. In a 25-mm-bore single-stage gun, using bulk-loaded propellant of 10 to 35 g, a muzzle speed up to 1.0 km/s was obtained. Time variations of propellant chamber pressures and in-tube projectile velocity profiles were measured. The liquid propellant combustion was initiated accompanying a delay time which was created due to the pyrolysis of the propellant. In order to obtain reliable ballistic range performance, the method of propellant loading was revealed to be critical. Since the burning rate of the liquid propellant is relatively low, the peak acceleration and the muzzle speed strongly depend on the rupture pressure of a diaphragm that was inserted between the launch tube and the propellant chamber. (author)

  7. 33 CFR 150.515 - What are the requirements for weight testing of newly installed or relocated craft?

    Science.gov (United States)

    2010-07-01

    ... weight testing of newly installed or relocated craft? 150.515 Section 150.515 Navigation and Navigable... testing of newly installed or relocated craft? (a) The operator must perform installation weight testing... (a) of this section, when survival crafts are relocated to another deepwater port. ...

  8. 46 CFR 24.15-5 - Canadian pleasure craft temporarily using navigable waters of the United States.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Canadian pleasure craft temporarily using navigable... SECURITY UNINSPECTED VESSELS GENERAL PROVISIONS Equivalents § 24.15-5 Canadian pleasure craft temporarily using navigable waters of the United States. Uninspected Canadian pleasure craft (uninspected vessels...

  9. 33 CFR 150.503 - What are the time interval requirements for maintenance on survival craft falls?

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false What are the time interval requirements for maintenance on survival craft falls? 150.503 Section 150.503 Navigation and Navigable Waters... maintenance on survival craft falls? (a) Each fall used in a launching device for survival craft or rescue...

  10. 46 CFR 25.25-17 - Survival craft requirements for uninspected passenger vessels of at least 100 gross tons.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Survival craft requirements for uninspected passenger... Survival craft requirements for uninspected passenger vessels of at least 100 gross tons. (a) Each uninspected passenger vessel of at least 100 gross tons must have adequate survival craft with enough capacity...

  11. 33 CFR 125.15 - Access to waterfront facilities, and port and harbor areas, including vessels and harbor craft...

    Science.gov (United States)

    2010-07-01

    ..., and port and harbor areas, including vessels and harbor craft therein. 125.15 Section 125.15....15 Access to waterfront facilities, and port and harbor areas, including vessels and harbor craft....09 to those waterfront facilities, and port and harbor areas, including vessels and harbor craft...

  12. 33 CFR 149.303 - What survival craft and rescue boats may be used on a manned deepwater port?

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false What survival craft and rescue boats may be used on a manned deepwater port? 149.303 Section 149.303 Navigation and Navigable Waters... craft and rescue boats may be used on a manned deepwater port? (a) Each survival craft on a manned...

  13. 25 CFR 309.24 - How will statements about Indian origin of art or craft products be interpreted?

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 2 2010-04-01 2010-04-01 false How will statements about Indian origin of art or craft products be interpreted? 309.24 Section 309.24 Indians INDIAN ARTS AND CRAFTS BOARD, DEPARTMENT OF THE INTERIOR PROTECTION OF INDIAN ARTS AND CRAFTS PRODUCTS § 309.24 How will statements about Indian origin of...

  14. 77 FR 32985 - Notice of Inventory Completion: U.S. Department of the Interior, Indian Arts and Crafts Board...

    Science.gov (United States)

    2012-06-04

    ... Inventory Completion: U.S. Department of the Interior, Indian Arts and Crafts Board, Museum of the Plains... Plains Indian, Indian Arts and Crafts Board, has completed an inventory of human remains, in consultation..., Indian Arts and Crafts Board. Disposition of the human remains to the Indian tribes stated below may...

  15. On shear rheology of gel propellants

    Energy Technology Data Exchange (ETDEWEB)

    Rahimi, Shai; Peretz, Arie [RAFAEL, MANOR Propulsion and Explosive Systems Division, Haifa (Israel); Natan, Benveniste [Faculty of Aerospace Engineering, Technion - Israel Institute of Technology, Haifa (Israel)

    2007-04-15

    Selected fuel, oxidizer and simulant gels were prepared and rheologically characterized using a rotational rheometer. For fuel gelation both organic and inorganic gellants were utilized, whereas oxidizers and simulants were gelled with addition of silica and polysaccharides, respectively. The generalized Herschel-Bulkley constitutive model was found to most adequately represent the gels studied. Hydrazine-based fuels, gelled with polysaccharides, were characterized as shear-thinning pseudoplastic fluids with low shear yield stress, whereas inhibited red-fuming nitric acid (IRFNA) and hydrogen peroxide oxidizers, gelled with silica, were characterized as yield thixotropic fluids with significant shear yield stress. Creep tests were conducted on two rheological types of gels with different gellant content and the results were fitted by Burgers-Kelvin viscoelastic constitutive model. The effect of temperature on the rheological properties of gel propellant simulants was also investigated. A general rheological classification of gel propellants and simulants is proposed. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

  16. Laser Initiated Ignition of Liquid Propellant

    Science.gov (United States)

    1991-01-31

    containers held in a water bath of constant temperature 70*C. A larger vessel containing approximately 2ml of propellant was also heated in each experiment and...controller. A stirrer and forced water circulation ensured that all samples were kept at the same temperature. The water wai first heated to the final 5... electrolysed samples. 3 .. .. ....... ......................... volume of 10 ....... . 5 ....... I • . ... .. . .... .. ...... .. . . .. . . ... . .61.8 2 22i

  17. Cryogenic Propellant Feed System Analytical Tool Development

    Science.gov (United States)

    Lusby, Brian S.; Miranda, Bruno M.; Collins, Jacob A.

    2011-01-01

    The Propulsion Systems Branch at NASA s Lyndon B. Johnson Space Center (JSC) has developed a parametric analytical tool to address the need to rapidly predict heat leak into propellant distribution lines based on insulation type, installation technique, line supports, penetrations, and instrumentation. The Propellant Feed System Analytical Tool (PFSAT) will also determine the optimum orifice diameter for an optional thermodynamic vent system (TVS) to counteract heat leak into the feed line and ensure temperature constraints at the end of the feed line are met. PFSAT was developed primarily using Fortran 90 code because of its number crunching power and the capability to directly access real fluid property subroutines in the Reference Fluid Thermodynamic and Transport Properties (REFPROP) Database developed by NIST. A Microsoft Excel front end user interface was implemented to provide convenient portability of PFSAT among a wide variety of potential users and its ability to utilize a user-friendly graphical user interface (GUI) developed in Visual Basic for Applications (VBA). The focus of PFSAT is on-orbit reaction control systems and orbital maneuvering systems, but it may be used to predict heat leak into ground-based transfer lines as well. PFSAT is expected to be used for rapid initial design of cryogenic propellant distribution lines and thermodynamic vent systems. Once validated, PFSAT will support concept trades for a variety of cryogenic fluid transfer systems on spacecraft, including planetary landers, transfer vehicles, and propellant depots, as well as surface-based transfer systems. The details of the development of PFSAT, its user interface, and the program structure will be presented.

  18. Bistable (latching) solenoid actuated propellant isolation valve

    Science.gov (United States)

    Wichmann, H.; Deboi, H. H.

    1979-01-01

    The design, fabrication, assembly and test of a development configuration bistable (latching) solenoid actuated propellant isolation valve suitable for the control hydrazine and liquid fluorine to an 800 pound thrust rocket engine is described. The valve features a balanced poppet, utilizing metal bellows, a hard poppet/seat interface and a flexure support system for the internal moving components. This support system eliminates sliding surfaces, thereby rendering the valve free of self generated particles.

  19. Low-cost silicon wafer dicing using a craft cutter

    KAUST Repository

    Fan, Yiqiang

    2014-05-20

    This paper reports a low-cost silicon wafer dicing technique using a commercial craft cutter. The 4-inch silicon wafers were scribed using a crafter cutter with a mounted diamond blade. The pre-programmed automated process can reach a minimum die feature of 3 mm by 3 mm. We performed this scribing process on the top polished surface of a silicon wafer; we also created a scribing method for the back-unpolished surface in order to protect the structures on the wafer during scribing. Compared with other wafer dicing methods, our proposed dicing technique is extremely low cost (lower than $1,000), and suitable for silicon wafer dicing in microelectromechanical or microfluidic fields, which usually have a relatively large die dimension. The proposed dicing technique is also usable for dicing multiple project wafers, a process where dies of different dimensions are diced on the same wafer.

  20. Professional Interventions as a State-Crafting Grammar

    DEFF Research Database (Denmark)

    Ydesen, Christian; Øland, Trine

    2015-01-01

    of reasoning. The second part titled ‘Theoretical concepts: State, Profession, Immigrant’ aims at presenting and clarifying the triad ‘state – profession – immigrant’ through the conceptual lens of state as a bureaucratic field and state-crafting. The third part designated ‘Working with historical sources......The first part under the headline ‘Theory and the construction of the research object’ will clarify our concept of theory and the Bourdieusian and Wacquantian way of working with theory and theoretical constructions when doing empirical and historical work as basis for the article’s chain......’ consists of three subsections altogether. The first addresses in brief the question of putting the theoretical model into work empirically focussing on the concept of field to avoid determinism and presentism when working with a com-prehensive theoretical framework. The second and third subsections takes...

  1. Understanding and crafting the mix the art of recording

    CERN Document Server

    Moylan, William

    2014-01-01

    Understanding and Crafting the Mix, 3rd edition provides the framework to identify, evaluate, and shape your recordings with clear and systematic methods. Featuring numerous exercises, this third edition allows you to develop critical listening and analytical skills to gain greater control over the quality of your recordings. Sample production sequences and descriptions of the recording engineer's role as composer, conductor, and performer provide you with a clear view of the entire recording process. Dr. William Moylan takes an inside look into a range of iconic popular music, thus offering insights into making meaningful sound judgments during recording. His unique focus on the aesthetic of recording and mixing will allow you to immediately and artfully apply his expertise while at the mixing desk. A companion website features recorded tracks to use in exercises, reference materials, additional examples of mixes and sound qualities, and mixed tracks.

  2. Crafting Sustainable Development Solutions: Frugal Innovations of Grassroots Entrepreneurs

    Directory of Open Access Journals (Sweden)

    Mario Pansera

    2016-01-01

    Full Text Available A shift in the entrepreneurial landscape is taking place brought about by grassroots innovators with little formal education and technological knowhow, living and working in penurious environments. This research represents an emerging third wave of literature on Bottom of the Pyramid innovation, where products are offered for and by the underserved. Using primary and secondary data derived from four cases of grassroots entrepreneurs in the Indian Subcontinent, the study explores the phenomenon where resource scarce entrepreneurs craft solutions that are environmental friendly, with low overall ownership costs, and use locally available material. We argue that the grassroots phenomenon can be fruitfully exploited to achieve the new Sustainable Development Goals proposed by the UN as a post-2015 strategy for the future of global governance. These innovations might have a tremendous impact not only in terms of serving unmet and ignored consumer needs, but also longer term impacts through enhanced productivity, sustainability, poverty reduction and inclusion promotion.

  3. Design- and Craft thinking analysed as Embodied Cognition

    Directory of Open Access Journals (Sweden)

    Camilla Groth

    2016-06-01

    Full Text Available Through the concept of design thinking the act of designing is presented as an intellectual activity, and the act of planning the design is elevated over the making process. However, the importance of materiality and the embodied sense-making that occurs in this context should not be forgotten. In this study, embodied cognition in design and craft practices was investigated through three case studies. The study takes on an enhanced tactile perspective as a methodological platform; thus, the cases involve 1 deafblind makers in ceramics, 2 a practice-led self-study report on tactile experiences while working with clay and 3 a study on design students’ use of their tactile sense during material exploration. The results show that the act of thinking design involves the body as a knowledge provider.

  4. Multipurpose stabilization of the advanced marine surface crafts

    Directory of Open Access Journals (Sweden)

    Sevostyanov Ruslan A.

    2016-01-01

    Full Text Available Advanced marine surface crafts, such as SWATHs, catamarans or hovercrafts become more and more popular for a great range of various tasks. They usually operate at much higher speed than conventional ships. Moreover, in the open sea there are a lot of requirements and restrictions concerning the quality of such crafts’ dynamics, especially in case of the wind or waves. This paper considers application of the control law with a special multipurpose structure for autopilot design for amphibious air cushion vehicles. Such control law allows to decompose the autopilot task into simpler optimization subtasks. Efficiency of this approach is shown in the task of stabilizing yaw angle of the air cushion vehicle in the different weather conditions.

  5. Small transport aircraft technology propeller study

    Science.gov (United States)

    Black, B. M.; Magliozzi, B.; Rohrbach, C.

    1983-01-01

    A study to define potential benefits of advanced technology propeller for 1985-1990 STAT commuter airplanes was completed. Two baselines, a Convair, 30 passenger, 0.47 Mach number airplane and a Lockheed, 50 passenger, 0.70 Mach number airplane, were selected from NASA-Ames sponsored airframe contracts. Parametric performance, noise level, weight and cost trends for propellers with varying number of blades, activity factor, camber and diameter incorporating blade sweep, tip proplets, advanced composite materials, advanced airfoils, advanced prevision synchrophasing and counter-rotation are presented. The resulting DOC, fuel burned, empty weight and acquisition cost benefits are presented for resizings of the two baseline airplanes. Six-bladed propeller having advanced composite blades, advanced airfoils, tip proplets and advanced prevision synchrophasers provided the maximum DOC improvements for both airplanes. DOC and fuel burned were reduced by 8.3% and 17.0% respectively for the Convair airplane and by 24.9% and 41.2% respectively for the Lockheed airplane. The larger reductions arose from a baseline definition with very heavy fuselage acoustic treatment. An alternate baseline, with a cabin noise 13dB in excess of the objective, was also studied.

  6. Striving towards improved Friedel-Crafts acylation catalysts

    International Nuclear Information System (INIS)

    Scott, N.M.; Deacon, G.B.

    1998-01-01

    Full text: Lanthanum, ytterbium and scandium salts of trifluoromethanesulfonic acid have been shown to act as promising Lewis acid catalysts for the Friedel-Craft acylation reactions. In our study catalytic acylation of anisole by acetic anhydride in nitroethane was investigated. Yields were determined after extraction of para-methoxyacetophenone from the reaction mixture by G.L.C using the external standardisation method. Anhydrous lanthanoid tris-triflate salts [Ln(O 3 SCF 3 ) 3 , Ln La, Y, Nd, Eu and Yb] were initially investigated as catalysts. Ytterbium tris-triflate was found to be the most effective giving ∼90% of the acylation product. The hydrated lanthanide tris-nitrate salts [Ln(NO 3 ) 3 .nH 2 O, Ln = La, Nd, Eu and Yb] were also investigated using in situ dehydration with acetic anhydride. These were found to have low solubility in the reaction mixture and gave poor yields of para-methoxyacetophenone. The formation of side products was suggested by the low total recovery of anisole and para-methoxyacetophenone. The blocking of coordination sites of these catalysts by tetraglyme resulted in a 50% reduction in acylation activity compared with the simple salt. Addition of Li(O 3 SCF 3 ) to Ln(O 3 SCF 3 ) 3 catalysts (ratio of 4:1)had only a slight accelerating effect on the Friedel-Crafts acylation reaction and the yield was only marginally greater than that in the absence of the added salt. In contrast Li(ClO 4 ) dramatically decreased reaction times and improved the yield of para-methoxyace-tophenone, as recently reported

  7. The impact of job crafting on job demands, job resources, and well-being.

    Science.gov (United States)

    Tims, Maria; Bakker, Arnold B; Derks, Daantje

    2013-04-01

    This longitudinal study examined whether employees can impact their own well-being by crafting their job demands and resources. Based on the job demands-resources model, we hypothesized that employee job crafting would have an impact on work engagement, job satisfaction, and burnout through changes in job demands and job resources. Data was collected in a chemical plant at three time points with one month in between the measurement waves (N = 288). The results of structural equation modeling showed that employees who crafted their job resources in the first month of the study showed an increase in their structural and social resources over the course of the study (2 months). This increase in job resources was positively related to employee well-being (increased engagement and job satisfaction, and decreased burnout). Crafting job demands did not result in a change in job demands, but results revealed direct effects of crafting challenging demands on increases in well-being. We conclude that employee job crafting has a positive impact on well-being and that employees therefore should be offered opportunities to craft their own jobs.

  8. Legal and economic implications of the German Craft Code Amendment 2004

    Directory of Open Access Journals (Sweden)

    Wolfgang Benzel

    2012-01-01

    Full Text Available As the main reason for initiating an amendment of the Trade and Crafts Code in 2004 was the decrease in the number of companies in general and the number of skilled crafts enterprises in particular and was also due to the fact that the number of employees in the skilled crafts sector had constantly fallen and many companies were not able to find a successor, it was the declared aim of the amendment to counter this structural crisis as well as reducing illegal employment and removing native discrimination. This would then ensure a higher level of employment especially through new company formations and takeovers of existing companies.In addition to providing an important contribution towards the assessment of the basic success of the 2004 Trade and Crafts Code amendment, the results can therefore be used at an international level for discussions on skilled crafts legislation outside Germany. As German skilled crafts legislation developed in a completely different manner from skilled crafts legislation in most other European countries, this aspect is particularly significant and it is conceivable that the results will be useful beyond the borders of the Federal Republic of Germany. The research findings will also be important in determining the limits of deregulation and when it can be considered counterproductive from an economic point of view.

  9. Analyzing components of Community Reinforcement and Family Training (CRAFT): Is treatment entry training sufficient?

    Science.gov (United States)

    Kirby, Kimberly C; Benishek, Lois A; Kerwin, MaryLouise E; Dugosh, Karen L; Carpenedo, Carolyn M; Bresani, Elena; Haugh, James A; Washio, Yukiko; Meyers, Robert J

    2017-11-01

    Community Reinforcement and Family Training (CRAFT) assists family members with a treatment-resistant loved one. The most consistent outcome of CRAFT is increased treatment entry of the identified treatment-resistant person (IP). This led us to question whether all 6 components of CRAFT are necessary. In a randomized clinical trial, 115 concerned significant others (CSOs) of an IP received 12-14 sessions of the full CRAFT intervention, 4-6 sessions focused on Treatment Entry Training (TEnT), or 12-14 sessions of Al-Anon/Nar-Anon Facilitation (ANF). We monitored treatment entry, attendance, and substance use of the IP and the CSO's mood and functioning. Data were collected at baseline and 4, 6, and 9 months after the baseline. We found significant reductions in time to treatment entry (χ(2)2 = 8.89, p = .01) and greater treatment entry rates for CRAFT (62%; odds ratio [OR] = 2.7, 95% confidence interval [CI] = 1.1-6.9) and TEnT (63%; OR = 2.9, 95% CI = 1.2-7.5) compared with ANF (37%), but CRAFT and TEnT did not differ significantly from each other (OR = 1.1, 95% CI = 0.4-2.7). No between-group differences in IP drug use were reported by CSOs, but days of drug use decreased over time for all groups (F(3, 277) = 13.47, p CRAFT produces greater treatment entry rates than ANF and found similar treatment entry rates for CRAFT and TEnT. This suggests that treatment entry training is sufficient for producing the best established outcome of CRAFT. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  10. Self-crafting vegetable snacks: testing the IKEA-effect in children.

    Science.gov (United States)

    Raghoebar, Sanne; van Kleef, Ellen; de Vet, Emely

    2017-01-01

    The purpose of this paper is to test whether the IKEA-effect (Norton et al. , 2012) - better liking for self-crafted products than for identical products crafted by others - can be exploited to increase liking and consumption of vegetable snacks in children. A between-subjects experiment was conducted at an after school care facility. In total, 86 children aged four to six either crafted a peacock with vegetables or with non-food objects following an example. After the task, children ate snack vegetables ad libitum, and rated their liking for the vegetables and pride in crafting the peacock. No significant main effect of the vegetable snack creation on consumption and liking was observed. Also, perceived pride did not mediate the effect of self-crafting vegetable snacks on consumption of and liking for vegetables. Vegetable consumption did not differ between children who were either simply exposed to vegetable snacks while crafting or those who were crafting the vegetable snacks themselves. The equal consumption might suggest that this is caused by simple exposure, but more research is needed comparing self-crafting and exposure to a condition where there is no initial exposure to vegetables. Although the IKEA-effect has been demonstrated in adults, this is one of the first studies evaluating the IKEA-effect in children and as a means to increase liking for a generally disliked product in this target group, i.e. vegetables. The IKEA-effect could not be replicated under these more stringent conditions, where the experimental set-up enabled disentangling exposure and crafting effects.

  11. High Job Demands, Still Engaged and Not Burned Out? The Role of Job Crafting.

    Science.gov (United States)

    Hakanen, Jari J; Seppälä, Piia; Peeters, Maria C W

    2017-08-01

    Traditionally, employee well-being has been considered as resulting from decent working conditions arranged by the organization. Much less is known about whether employees themselves can make self-initiated changes to their work, i.e., craft their jobs, in order to stay well, even in highly demanding work situations. The aim of this study was to use the job demands-resources (JD-R model) to investigate whether job crafting buffers the negative impacts of four types of job demands (workload, emotional dissonance, work contents, and physical demands) on burnout and work engagement. A questionnaire study was designed to examine the buffering role of job crafting among 470 Finnish dentists. All in all, 11 out of 16 possible interaction effects of job demands and job crafting on employee well-being were significant. Job crafting particularly buffered the negative effects of job demands on burnout (7/8 significant interactions) and to a somewhat lesser extent also on work engagement (4/8 significant interactions). Applying job crafting techniques appeared to be particularly effective in mitigating the negative effects of quantitative workload (4/4 significant interactions). By demonstrating that job crafting can also buffer the negative impacts of high job demands on employee well-being, this study contributed to the JD-R model as it suggests that job crafting may even be possible under high work demands, and not only in resourceful jobs, as most previous studies have indicated. In addition to the top-down initiatives for improving employee well-being, bottom-up approaches such as job crafting may also be efficient in preventing burnout and enhancing work engagement.

  12. Arts and Crafts Classes in Years I–III, Based on Methods Featuring Pupils’ Practical Activities

    OpenAIRE

    Piwowarska, Ewa

    2016-01-01

    The issue to be analysed here concerns teachers’ planning of arts and crafts classes in Years I–III, with specific reference to methods featuring pupils’ practical activities. A theoretical part briefly presents the concepts involved in teaching a subject that was initially defined as drawing, then as arts and crafts education, and finally as arts and crafts classes. It points out the factors that influence the process of stimulating pupils’ artistic activities. The technique used in the cour...

  13. Use your eyes - metallographic versus superficial traces of the crafting of Bronze Age ornaments

    DEFF Research Database (Denmark)

    Nørgaard, Heide Wrobel

    and superficial archaeological examinations can be used to understand prehistoric craft. Furthermore, it will show that with an intensive knowledge about previous scientific investigations the superficial traces preserved can reveal a great amount of information and could talk for themselves. Taking as an example...... the early and middle Bronze Age bronze ornaments from North Germany, superficial traces of the metal crafting process, visible with the naked eye, will be compared with metallographic images. The aim of this presentation is to give an overview over the crafting traces everybody could see (with a bit...

  14. The effects of job crafting on subjective well-being amongst South African high school teachers

    Directory of Open Access Journals (Sweden)

    Sergio Peral

    2016-09-01

    Full Text Available Orientation: Job crafting can result in a number of positive outcomes for teachers, such as increased meaningfulness and engagement at work. Increased work engagement and psychological meaningfulness may yield positive benefits for the practice of teaching, thus highlighting the pivotal role of job crafting. Research purpose: The study’s aim was to investigate the relationship between job crafting and subjective well-being amongst South African high school teachers. Subjective well-being comprises psychological meaningfulness and work engagement. The potential mediating effect that psychological meaningfulness had on this relationship was further explored. Motivation for the study: Being in a highly stressful occupation, teachers need to continuously find ways to craft their working practices in order to deal effectively with their job demands and to capitalise on their available job resources. Furthermore, South Africa’s current education system calls for serious proactive measures to be taken to improve and rectify the current status, such as job crafting. Research approach, design and method: A quantitative, cross-sectional survey design was used and administered to a sample of South African high school teachers situated in Gauteng, South Africa (N = 251. Main findings: A positive relationship was found between job crafting (increasing structural resources and challenging job demands and work engagement. Furthermore, psychological meaningfulness mediated the relationship between job crafting and work engagement amongst the sampled high school teachers. Practical/managerial implications: Teachers who craft their work to better suit their preferences and needs will obtain greater meaning in their work and experience increased levels of work engagement. Training programmes and/or group-based interventions targeted around job crafting techniques may be particularly useful in the South African teaching context. Contribution/value-add: This

  15. Taking control: Is job crafting related to the intention to leave surgical training?

    Science.gov (United States)

    Dominguez, Luis Carlos; Stassen, Laurents; de Grave, Willem; Sanabria, Alvaro; Alfonso, Edgar; Dolmans, Diana

    2018-01-01

    The intention to leave surgical training, hereinafter referred as proxy of "attrition," is associated with poor well-being in the workplace. Attrition is suggested to diminish when residents possess job-crafting skills, that is, the ability to redefine their job in meaningful ways and maximize well-being at work by increasing structural and social resources and challenges and decreasing hindering demands. However, the evidence supporting this relationship is scant. This study sought to: 1) investigate to what extent residents possess job-crafting skills and compare residents' levels of job-crafting skills across years of residency training; 2) investigate the relationship between job crafting, well-being as measured by burnout and work-engagement rates, and the intention to leave; and 3) compare the levels of job-crafting skills and well-being between residents with and without serious intentions to leave. This cross sectional study was conducted in fifteen residency programs in Colombia. Surgical residents completed different questionnaires including the Dutch Job Crafting Scale (DJCS), MBI-Human Services Survey (MBI-HSS), Utrecht Work Engagement Scale (UWES-17) and an adapted version of the Nurse Turnover Intention Scale (NTIS). The objectives were addressed by independent analyses of variance (ANOVA), structural equation modeling techniques (SEM) and independent t-tests, respectively. A total of 202 residents participated. Residents generally scored high on their job-crafting skills to increase structural and social resources as well as challenging demands, but were less positive about their skills to reduce hindering demands. No differences across years of training were found. Job crafting correlated positively with work-engagement, which was inversely related to the intention to leave. Conversely, job crafting correlated negatively with burnout, which bore a positive relationship to the intention to leave. Residents with serious intentions to leave exhibited

  16. Preservation of Cultural Heritage Embodied in Traditional Crafts in the Developing Countries. A Case Study of Pakistani Handicraft Industry

    Directory of Open Access Journals (Sweden)

    Yongzhong Yang

    2018-04-01

    Full Text Available Cultural heritage embodied in traditional crafts is an integral part of any nation which reflects the culture and tradition of a particular region. Although the importance of handicraft has been widely recognized, the literature regarding preservation of traditional craft is scarce. The present paper aimed to explore and identify issues faced by traditional craftsmanship in developing countries and to address those issues in order to contribute to the sustainability of traditional craft heritage and ensure continuous transmission of craft skills and knowledge from generation to generation. Our study identified several key issues which poses substantial challenges to the preservation of traditional craft heritage in developing countries. In order to add empirical evidence, we examined the case of Pakistani handicraft industry that provided further understanding of highlighted issues which traditional craft heritage face. We have suggested some policies to promote, develop and preserve the traditional craft heritage. The significance of these policy suggestions is underlined with the case study of Pakistan.

  17. Development of HAN-based Liquid Propellant Thruster

    Science.gov (United States)

    Hisatsune, K.; Izumi, J.; Tsutaya, H.; Furukawa, K.

    2004-10-01

    Many of propellants that are applied to the conventional spacecraft propulsion system are toxic propellants. Because of its toxicity, considering the environmental pollution or safety on handling, it will be necessary to apply the "green" propellant to the spacecraft propulsion system. The purpose of this study is to apply HAN based liquid propellant (LP1846) to mono propellant thruster. Compared to the hydrazine that is used in conventional mono propellant thruster, HAN based propellant is not only lower toxic but also can obtain higher specific impulse. Moreover, HAN based propellant can be decomposed by the catalyst. It means there are the possibility of applying to the mono propellant thruster that can leads to the high reliability of the propulsion system.[1],[2] However, there are two technical subjects, to apply HAN based propellant to the mono propellant thruster. One is the high combustion temperature. The catalyst will be damaged under high temperature condition. The other is the low catalytic activity. It is the serious problem on application of HAN based propellant to the mono propellant thruster that is used for attitude control of spacecraft. To improve the catalytic activity of HAN based propellant, it is necessary to screen the best catalyst for HAN based propellant. The adsorption analysis is conducted by Monte Carlo Simulation to screen the catalyst metal for HAN and TEAN. The result of analysis shows the Iridium is the best catalyst metal for HAN and TEAN. Iridium is the catalyst metal that is used at conventional mono propellant thruster catalyst Shell405. Then, to confirm the result of analysis, the reaction test about catalyst is conducted. The result of this test is the same as the result of adsorption analysis. That means the adsorption analysis is effective in screening the catalyst metal. At the evaluating test, the various types of carrier of catalyst are also compared to Shell 405 to improve catalytic activity. The test result shows the

  18. 25 CFR 309.9 - When can non-Indians make and sell products in the style of Indian arts and crafts?

    Science.gov (United States)

    2010-04-01

    ... of Indian arts and crafts? 309.9 Section 309.9 Indians INDIAN ARTS AND CRAFTS BOARD, DEPARTMENT OF THE INTERIOR PROTECTION OF INDIAN ARTS AND CRAFTS PRODUCTS § 309.9 When can non-Indians make and sell products in the style of Indian arts and crafts? A non-Indian can make and sell products in the style of...

  19. 25 CFR 309.1 - How do the regulations in this part carry out the Indian Arts and Crafts Act of 1990?

    Science.gov (United States)

    2010-04-01

    ... Arts and Crafts Act of 1990? 309.1 Section 309.1 Indians INDIAN ARTS AND CRAFTS BOARD, DEPARTMENT OF THE INTERIOR PROTECTION OF INDIAN ARTS AND CRAFTS PRODUCTS § 309.1 How do the regulations in this part carry out the Indian Arts and Crafts Act of 1990? These regulations define the nature and Indian origin...

  20. A 3D imaging system for the non-intrusive in-flight measurement of the deformation of an aircraft propeller and a helicopter rotor

    Science.gov (United States)

    Stasicki, Bolesław; Boden, Fritz; Ludwikowski, Krzysztof

    2017-02-01

    The non-intrusive in-flight deformation measurement and the resulting local pitch of an aircraft propeller or helicopter rotor blade is a demanding task. The idea of an imaging system integrated and rotating with the air-craft propeller has already been presented at the 30th International Congress on High-Speed Imaging and Photonics (ICHSIP30) in 2012. Since then this system has been designed, constructed and tested in the laboratory as well as in-flight on the Cobra VUT100 of Evektor Aerotechnik, Kunovice (CZ). The major aim of the EU FP7 project AIM2 ("Advanced In-flight Measurement techniques 2" - contract No. 266107) was to ascertain the feasibility of this technique under extreme conditions - vibration and large centrifugal forces - to real flight testing. Based on the gained experience a new rotating system for the application on helicopter rotors has recently been constructed and tested on the whirl tower of Airbus Helicopters, Donauwoerth (D). In this paper the principle of the applied Image Pattern Correlation Technique (IPCT), a specialized type of Digital Image Correlation (DIC), is outlined and the construction of both rotating 3D image acquisition systems dedicated to the in-flight deformation measurement of the aircraft propeller and helicopter rotor are described. Furthermore, the results of the ground and in-flight tests of these systems will be shown and discussed. The obtained results will be helpful for manufacturers in the design of their future aircrafts.

  1. Numerical Analysis of Ice Impacts on Azimuth Propeller

    Science.gov (United States)

    2013-09-01

    uniformity as one solid object, though the built-on process is recognized as well. The number of blades for this propeller varies to control cavitation ...Figure 7). The CRP allows the hydrodynamic advantage of regaining lost rotational energy from the first propeller, which is the conventional...it speeds flow through and accelerates it past the propellers. Decelerating duct slows the flow and allows for greatly reduced cavitation and

  2. A Portable Burn Pan for the Disposal of Excess Propellants

    Science.gov (United States)

    2016-06-01

    2013 - 06/01/2016 A Portable Burn Pan for the Disposal of Excess Propellants Michael Walsh USA CRREL USA CRREL 72 Lyme Road Hanover, NH 03755...Army Alaska XRF X-Ray Florescence vii ACKNOWLEDGEMENTS Project ER-201323, A Portable Burn Pan for the Disposal of Gun Propellants, was a very...contamination problem while allowing troops to train as they fight, we have developed a portable training device for burning excess gun propellants. 1.1

  3. Computer aided design and development of mixed-propeller pumps

    International Nuclear Information System (INIS)

    Bhaoyal, B.C.

    1994-01-01

    This paper deals with the design principle of mixed propeller hydraulic aided by CADD software developed by author for generation of the hydraulic profile of the mixed propeller and diffuser geometry. The design methodology for plotting the vane profile of mixed propeller pump has been discussed in detail with special reference to conformal transformation in cylindrical as well as conical plane. (author). 10 refs., 11 figs

  4. Electric Propellant Solid Rocket Motor Thruster Results Enabling Small Satellites

    OpenAIRE

    Koehler, Frederick; Langhenry, Mark; Summers, Matt; Villarreal, James; Villarreal, Thomas

    2017-01-01

    Raytheon Missile Systems has developed and tested true on/off/restart solid propellant thrusters which are controlled only by electrical current. This new patented class of energetic rocket propellant is safe, controllable and simple. The range of applications for this game changing technology includes attitude control systems and a safe alternative to higher impulse space satellite thrusters. Described herein are descriptions and performance data for several small electric propellant solid r...

  5. Solid propellant processing factor in rocket motor design

    Science.gov (United States)

    1971-01-01

    The ways are described by which propellant processing is affected by choices made in designing rocket engines. Tradeoff studies, design proof or scaleup studies, and special design features are presented that are required to obtain high product quality, and optimum processing costs. Processing is considered to include the operational steps involved with the lining and preparation of the motor case for the grain; the procurement of propellant raw materials; and propellant mixing, casting or extrusion, curing, machining, and finishing. The design criteria, recommended practices, and propellant formulations are included.

  6. High Impulse Nanoparticulate-Based Gel Propellants, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposed Small Business Innovative Research (SBIR) Phase I addresses the development of advanced gel propellants and determination of their suitability for...

  7. Legal status of crew members on pleasure craft and vessels used in nautical tourism

    Directory of Open Access Journals (Sweden)

    Giovanni Marchiafava

    2018-02-01

    Full Text Available The paper aims at examining the issues related to the legal status of crew members of pleasure craft and vessels used in nautical tourism from an Italian perspective. Firstly, the definition of crew and its composition on pleasure craft and vessels is examined. Additionally, the legal regime of crew members together with the crew on-board documentation, is discussed. Furthermore, the main similarities and dissimilarities of the crew regime according to the type of pleasure craft and vessel and their use, as well as, the on-board services, is dealt with. Finally, the issue related to the legal classification of ‘’guests’’, undertaking complementary on-board services of pleasure craft and vessels is considered.

  8. Cooking and Hammering: Primary School Pupils' Concepts of their Craft Skills

    Directory of Open Access Journals (Sweden)

    Mare MÜÜRSEPP

    2014-07-01

    Full Text Available The aim of the study is to clear the significance of craft skills for the pupils in age nine and twelve years. More than 200 pupils were asked to define, what are the most important skills for the pupils of their age. The results bring out that category of the skills related to craft subject is of the most presented categories in pupils' self description. Thus the primary school pupils essentially defined themselves by the activities they could do practically (building, cooking, repairing of things. The most undefined relation to craft activities is reflected in the answer of smaller boys in our study. A suspicion arisen from the analysis of pupils' sayings, that the craft lessons in the 1st school stage tend to be organized kind of poorly was asserted by the teachers who pointed out the need for special rooms and materials to implement different techniques.

  9. A novel kind of solid rocket propellant

    Energy Technology Data Exchange (ETDEWEB)

    Lo, R.E. [Berlin University of Technology (Germany). Rocket Technology at the Aerospace Institute (ILR)

    1998-09-01

    Cryogenic Solid Propellants (CSPs) combine the simplicity of conventional solid propulsion with the high performance of liquid propulsion. By introducing materials that require cooling for remaining solid, CSPs offer an almost unlimited choice of propellant constituents that mights be selected with respect to specific impulse, density or environmental protection. The prize to be paid for these advantages is the necessity of constant cooling and the requirement of special design features that provide combustion control by moving from deflagration to hybrid like boundary layer combustion. This is achieved by building the solid propellant grains out of macroscopic elements rather than using the quasi homogeneous mixture of conventional composites. The elements may be coated, providing protection and support. Different elements may be designed for individual tasks and serve as modules for ignition, sustained combustion, gas generation, combustion efficiency enhancement, etc. Modular dissected grains offer many new ways of interaction inside the combustion chamber and new degrees of freedom for the designer of such `multiple internal hybrid grains`. At a preliminary level, a study finished in Germany 1997 demonstrated large payload gains when the US space Shuttle and the ARIANE 5 boosters were replaced by CSP-boosters. A very preliminary cost analysis resulted in development costs in the usual magnitude (but not in higher ones). Costs of operation were identified as crucial, but not established. Some experimental work in Germany is scheduled to begin in 1998, almost all details in this article (and many more that were not mentioned - most prominent cost analyses of CSP development and operations) wait for deeper analysis and verification. Actually, a whole new world new of world of chemical propulsion awaits exploration. The topic can be looked up and discussed at the web site of the Advanced Propulsion Workshop of the International Academy of Astronautics. The author

  10. 75 FR 62333 - Airworthiness Directives; Hamilton Sundstrand Propellers Model 247F Propellers

    Science.gov (United States)

    2010-10-08

    ...., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory... that the 247F propeller blades, P/N 817370-1, S/Ns FR2449 to FR2958 inclusive, FR20010710 to FR20010722 inclusive, and FR20010723RT to FR20020127RT inclusive, manufactured since January 1999, might also have...

  11. 76 FR 25534 - Airworthiness Directives; Hamilton Sundstrand Propellers Model 247F Propellers

    Science.gov (United States)

    2011-05-05

    ... 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this AD, the... through FR2279 inclusive, FR 2398, FR2449 to FR2958 inclusive, FR20010710 to FR20010722 inclusive, and FR20010723RT to FR20020127RT inclusive, installed. Propeller blades reworked to Hamilton Sundstrand Service...

  12. Thermal Vacuum Test Correlation of A Zero Propellant Load Case Thermal Capacitance Propellant Gauging Analytics Model

    Science.gov (United States)

    McKim, Stephen A.

    2016-01-01

    This thesis describes the development and test data validation of the thermal model that is the foundation of a thermal capacitance spacecraft propellant load estimator. Specific details of creating the thermal model for the diaphragm propellant tank used on NASA's Magnetospheric Multiscale spacecraft using ANSYS and the correlation process implemented to validate the model are presented. The thermal model was correlated to within plus or minus 3 degrees Centigrade of the thermal vacuum test data, and was found to be relatively insensitive to uncertainties in applied heat flux and mass knowledge of the tank. More work is needed, however, to refine the thermal model to further improve temperature predictions in the upper hemisphere of the propellant tank. Temperatures predictions in this portion were found to be 2-2.5 degrees Centigrade lower than the test data. A road map to apply the model to predict propellant loads on the actual MMS spacecraft toward its end of life in 2017-2018 is also presented.

  13. WOW: light print, light propel, light point

    DEFF Research Database (Denmark)

    Glückstad, Jesper; Bañas, Andrew Rafael; Aabo, Thomas

    2012-01-01

    anywhere in a sample at any orientation using real-time 3D optical micromanipulation with six degrees of freedom. One of the key aspects of our demonstrated WOWs is the change in direction of in-coupled light and the marked increase in numerical aperture of the out-coupled light. Hence, each light...... propelled WOW can tap from a relatively broad incident beam and generate a much more tightly confined light at its tip. The presentation contains both numerical simulations related to the propagation of light through a WOW and preliminary experimental demonstrations on our BioPhotonics Workstation...

  14. PHM Enabled Autonomous Propellant Loading Operations

    Science.gov (United States)

    Walker, Mark; Figueroa, Fernando

    2017-01-01

    The utility of Prognostics and Health Management (PHM) software capability applied to Autonomous Operations (AO) remains an active research area within aerospace applications. The ability to gain insight into which assets and subsystems are functioning properly, along with the derivation of confident predictions concerning future ability, reliability, and availability, are important enablers for making sound mission planning decisions. When coupled with software that fully supports mission planning and execution, an integrated solution can be developed that leverages state assessment and estimation for the purposes of delivering autonomous operations. The authors have been applying this integrated, model-based approach to the autonomous loading of cryogenic spacecraft propellants at Kennedy Space Center.

  15. High Power Flex-Propellant Arcjet Performance

    Science.gov (United States)

    Litchford, Ron J.

    2011-01-01

    A MW-class electrothermal arcjet based on a water-cooled, wall-stabilized, constricted arc discharge configuration was subjected to extensive performance testing using hydrogen and simulated ammonia propellants with the deliberate aim of advancing technology readiness level for potential space propulsion applications. The breadboard design incorporates alternating conductor/insulator wafers to form a discharge barrel enclosure with a 2.5-cm internal bore diameter and an overall length of approximately 1 meter. Swirling propellant flow is introduced into the barrel, and a DC arc discharge mode is established between a backplate tungsten cathode button and a downstream ringanode/ spin-coil assembly. The arc-heated propellant then enters a short mixing plenum and is accelerated through a converging-diverging graphite nozzle. This innovative design configuration differs substantially from conventional arcjet thrusters, in which the throat functions as constrictor and the expansion nozzle serves as the anode, and permits the attainment of an equilibrium sonic throat (EST) condition. During the test program, applied electrical input power was varied between 0.5-1 MW with hydrogen and simulated ammonia flow rates in the range of 4-12 g/s and 15-35 g/s, respectively. The ranges of investigated specific input energy therefore fell between 50-250 MJ/kg for hydrogen and 10-60 MJ/kg for ammonia. In both cases, observed arc efficiencies were between 40-60 percent as determined via a simple heat balance method based on electrical input power and coolant water calorimeter measurements. These experimental results were found to be in excellent agreement with theoretical chemical equilibrium predictions, thereby validating the EST assumption and enabling the utilization of standard TDK nozzle expansion analyses to reliably infer baseline thruster performance characteristics. Inferred specific impulse performance accounting for recombination kinetics during the expansion process

  16. SUSTAINABLE WASTE MANAGEMENT OF TRADITIONAL CRAFT INDUSTRY IN LOPATI TOURISM VILLAGE, YOGYAKARTA

    OpenAIRE

    VITASURYA Vincentia Reni; PUDIANTI Anna

    2016-01-01

    Ecotourism has been growing in Yogyakarta that can be seen through the development of rural tourism. The development of rural tourism has positive impact to improve local community’s welfare nevertheless, it has also negative impact onto environmental carrying capacity. Lopati tourism village is located in Bantul, Yogyakarta, relying on traditional craft industry as tourism attraction. Traditional crafts are livelihood of local residents, so that environmental management efforts become part o...

  17. Investigations of Thickness Requirement in DNV Rules for High-Speed Craft

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Zhang, Shengming

    1997-01-01

    Simple formulas for determining impact strength of high-speed craft collisions with floating objects are given in this note. Thereby the minimum mass of a floating object that just ruptures the shell plating is predicted. The minimum thickness requirements of DNV rules for aluminiumcrafts and GRP...... single skin crafts can be converted to critical impact energy and minimum object mass. Some comparisons show an acceptable agreement between present method and DNV test results....

  18. Job crafting, work engagement, and psychological distress among Japanese employees: a cross-sectional study.

    Science.gov (United States)

    Sakuraya, Asuka; Shimazu, Akihito; Eguchi, Hisashi; Kamiyama, Kimika; Hara, Yujiro; Namba, Katsuyuki; Kawakami, Norito

    2017-01-01

    Job crafting, an employee-initiated job design/redesign, has become important for employees' well-being. However, most studies on the relationship between job crafting and employees' well-being have been conducted in western countries; thus, it is unclear whether job crafting can be effectively applied to Asian cultures, such as Japan, which emphasizes group harmony. The aim of this study was to examine the cross-sectional associations of self-reported job crafting with work engagement and psychological distress among employees in Japan. A questionnaire survey through the internet was conducted among all employees of a manufacturing company in Japan. We analyzed the data from 894 respondents, all employees with regular employment. Job crafting, work engagement, and psychological distress were assessed using the Japanese version of the Job Crafting Questionnaire, the Japanese version of the Utrecht Work Engagement Scale (UWES), and the Brief Job Stress Questionnaire (BJSQ), respectively. Hierarchical multiple regression showed that increasing structural job resources, social job resources, and challenging job demands was significantly and positively associated with work engagement ( β  = 0.31, p  engagement and lower psychological distress. In addition, increasing social job resources and challenging job demands are also associated with higher work engagement.

  19. Purpose and pleasure in late life: Conceptualising older women's participation in art and craft activities.

    Science.gov (United States)

    Liddle, Jeannine L M; Parkinson, Lynne; Sibbritt, David W

    2013-12-01

    The fourth age, as the last stage of life, represents a final challenge to find personal meaning in the face of changing capacities, illness and disability. Participation in valued activities is important for sustaining interest in life and has been associated with enhanced health and well-being. Art and craft activities are a popular form of participation amongst women in late life with growing international interest in the potential for these types of activities to maintain health and well-being and address problems of social isolation. Drawing on open text comments from 114 women enrolled in the Australian Longitudinal Study on Women's Health and in-depth interviews with 23 women all aged in their eighties, this paper explores the nature of older women's participation in art and craft activities and conceptualises links between participation in these activities and health and well-being in late life. Participation in art and craft activities is complex and dynamic, comprising cognitive and physical processes infused with emotion and occurs in the context of social relationships, physical spaces, physical ailments and beliefs about the value of the activities. By participating in art and craft activities, older women find purpose in their lives, contributing to their subjective well-being whilst helping and being appreciated by others. They develop a self view as enabled and as such take on new art and craft challenges, continue to learn and develop as art and craft makers and remain open to new possibilities. © 2013.

  20. Job crafting among health care professionals: The role of work engagement.

    Science.gov (United States)

    Bakker, Arnold B

    2018-04-01

    The aim of this study was to examine the impact of job crafting on the quality of the work environment of health care professionals. Job crafting refers to proactive behavior aimed at optimizing the fit between person and job. Using job demands-resources theory, we hypothesized that job crafting would be positively related to job resources and person-organisation fit, and negatively to hindrance demands. Furthermore, we hypothesized that these relationships would be qualified by work engagement. A total of 5,272 health care professionals from one of 35 different organisations filled out an electronic questionnaire (response is 55%). Regression analyses were used to test hypotheses. Consistent with hypotheses, job crafting in the form of increasing job resources was positively related to opportunities for development, performance feedback and P-O fit; and negatively related to hindrance job demands - particularly when work engagement was high. The combination of job crafting and work engagement is important for the realization of a resourceful work environment and fit between person and organisation. Interventions aimed at fostering job crafting should be tailored to the motivation of health care professionals. © 2017 John Wiley & Sons Ltd.

  1. Electrical Safety Program: Nonelectrical Crafts at LANL, Live #12175

    Energy Technology Data Exchange (ETDEWEB)

    Glass, George [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-12-22

    Los Alamos National Laboratory (LANL) and the federal government require those working with or near electrical equipment to be trained on electrical hazards and how to avoid them. Although you might not be trained to work on electrical systems, your understanding of electricity, how it can hurt you, and what precautions to take when working near electricity could save you or others from injury or death. This course, Electrical Safety Program: Nonelectrical Crafts at LANL (12175), provides knowledge of basic electrical concepts, such as current, voltage, and resistance, and their relationship to each other. You will learn how to apply these concepts to safe work practices while learning about the dangers of electricity—and associated hazards—that you may encounter on the job. The course also discusses what you can do to prevent electrical accidents and what you should do in the event of an electrical emergency. The LANL Electrical Safety Program is defined by LANL Procedure (P) 101-13. An electrical safety officer (ESO) is well versed in this document and should be consulted regarding electrical questions. Appointed by the responsible line manager (RLM), ESOs can tell you if a piece of equipment or an operation is safe or how to make it safe.

  2. New Methods for Crafting Locally Decision-Relevant Scenarios

    Science.gov (United States)

    Lempert, R. J.

    2015-12-01

    Scenarios can play an important role in helping decision makers to imagine future worlds, both good and bad, different than the one with which we are familiar and to take concrete steps now to address the risks generated by climate change. At their best, scenarios can effectively represent deep uncertainty; integrate over multiple domains; and enable parties with different expectation and values to expand the range of futures they consider, to see the world from different points of view, and to grapple seriously with the potential implications of surprising or inconvenient futures. These attributes of scenario processes can prove crucial in helping craft effective responses to climate change. But traditional scenario methods can also fail to overcome difficulties related to choosing, communicating, and using scenarios to identify, evaluate, and reach consensus on appropriate policies. Such challenges can limit scenario's impact in broad public discourse. This talk will demonstrate how new decision support approaches can employ new quantitative tools that allow scenarios to emerge from a process of deliberation with analysis among stakeholders, rather than serve as inputs to it, thereby increasing the impacts of scenarios on decision making. This talk will demonstrate these methods in the design of a decision support tool to help residents of low lying coastal cities grapple with the long-term risks of sea level rise. In particular, this talk will show how information from the IPCC SSP's can be combined with local information to provide a rich set of locally decision-relevant information.

  3. Blade Section Lift Coefficients for Propellers at Extreme Off-Design Conditions

    National Research Council Canada - National Science Library

    Shen, Young

    1997-01-01

    The Propeller Force Module (PFM) code developed by Analytical Methods Inc. (AMI) for calculating propeller side forces during maneuvering simulation studies requires inputs of propeller blade sectional lift, drag, and moment data...

  4. Mars Propellant Liquefaction Modeling in Thermal Desktop

    Science.gov (United States)

    Desai, Pooja; Hauser, Dan; Sutherlin, Steven

    2017-01-01

    NASAs current Mars architectures are assuming the production and storage of 23 tons of liquid oxygen on the surface of Mars over a duration of 500+ days. In order to do this in a mass efficient manner, an energy efficient refrigeration system will be required. Based on previous analysis NASA has decided to do all liquefaction in the propulsion vehicle storage tanks. In order to allow for transient Martian environmental effects, a propellant liquefaction and storage system for a Mars Ascent Vehicle (MAV) was modeled using Thermal Desktop. The model consisted of a propellant tank containing a broad area cooling loop heat exchanger integrated with a reverse turbo Brayton cryocooler. Cryocooler sizing and performance modeling was conducted using MAV diurnal heat loads and radiator rejection temperatures predicted from a previous thermal model of the MAV. A system was also sized and modeled using an alternative heat rejection system that relies on a forced convection heat exchanger. Cryocooler mass, input power, and heat rejection for both systems were estimated and compared against sizing based on non-transient sizing estimates.

  5. 14 CFR 35.21 - Variable and reversible pitch propellers.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Variable and reversible pitch propellers. 35.21 Section 35.21 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: PROPELLERS Design and Construction § 35.21 Variable and...

  6. Prediction of propeller-induced hull-pressure fluctuations

    NARCIS (Netherlands)

    Van Wijngaarden, H.C.J.

    2011-01-01

    The cavitating propeller often forms the primary source of noise and vibration on board ships. The propeller induces hydroacoustic pressure fluctuations due to the passing blades and, more importantly, the dynamic activity of cavities in the propeller’s immediate vicinity. The accurate prediction of

  7. Self-propelled oil droplets consuming "fuel" surfactant

    DEFF Research Database (Denmark)

    Toyota, Taro; Maru, Naoto; Hanczyc, Martin M

    2009-01-01

    A micrometer-sized oil droplet of 4-octylaniline containing 5 mol % of an amphiphilic catalyst exhibited a self-propelled motion, producing tiny oil droplets, in an aqueous dispersion of an amphiphilic precursor of 4-octylaniline. The tiny droplets on the surface of the self-propelled droplet wer...

  8. Propellant and Purge System Contamination "2007: A Summer of Fun"

    Science.gov (United States)

    Galloway, Randy

    2010-01-01

    This slide presentation reviews the propellant and purge system contamination that occurred during the summer of 2007 at Stennis Space Center. During this period Multiple propellant/pressurant system contamination events prompted a thorough investigation, the results of which are reviewed.

  9. Propeller flaps for lower-limb trauma | Rogers | South African ...

    African Journals Online (AJOL)

    The propeller flap has become a versatile and important component in our reconstructive algorithm following complex lower limb trauma. First described by Hyakusoku in 1991, it has since been adapted and modified by Hallock and Teo. This article outlines our experience specifically with perforator pedicled propeller flaps ...

  10. Current state of the art of HNF based composite propellants

    NARCIS (Netherlands)

    Ciucci, A.; Frota, O.; Welland, W.H.M.; Heijden, A.E.D.M. van der; Leeming, B.; Bellerby, J.M.; Brotzu, A.

    2004-01-01

    The main activities currently performed for the development of HNF-based propellants are presented. The objectives and approach adopted are described. The results obtained on the HNF decomposition mechanism and on the re- and co-crystallisation of HNF with potential propellant ingredients are

  11. Development of strand burner for solid propellant burning rate studies

    International Nuclear Information System (INIS)

    Aziz, A; Mamat, R; Ali, W K Wan

    2013-01-01

    It is well-known that a strand burner is an apparatus that provides burning rate measurements of a solid propellant at an elevated pressure in order to obtain the burning characteristics of a propellant. This paper describes the facilities developed by author that was used in his studies. The burning rate characteristics of solid propellant have be evaluated over five different chamber pressures ranging from 1 atm to 31 atm using a strand burner. The strand burner has a mounting stand that allows the propellant strand to be mounted vertically. The strand was ignited electrically using hot wire, and the burning time was recorded by electronic timer. Wire technique was used to measure the burning rate. Preliminary results from these techniques are presented. This study shows that the strand burner can be used on propellant strands to obtain accurate low pressure burning rate data

  12. EFD and CFD Characterization of a CLT Propeller

    Directory of Open Access Journals (Sweden)

    Daniele Bertetta

    2012-01-01

    Full Text Available In the present paper an experimental and numerical analysis of an unconventional CLT propeller is carried out. Two different numerical approaches, a potential panel method and an RANSE solver, are employed. Cavitation tunnel experiments are carried out in order to measure, as usual, thrust, torque, and cavity extension for different propeller working points. Moreover, LDV measurements are performed to have a deep insight into the complex wake behind the propeller and to analyze the dynamics of generated tip vortexes. The numerical/experimental analysis and comparison of results highlight the peculiarities of this kind of propellers, the possibility to increase efficiency and reduce cavitation risk, in order to exploit the design approaches already well proven for conventional propellers also in the case of these unconventional geometries.

  13. Greener Friedel-Crafts Acylation using Microwave-enhanced reactivity of Bismuth Triflate in the Friedel-Crafts Benzoylation of Aromatic Compounds with Benzoic Anhydride

    DEFF Research Database (Denmark)

    Tran, Phuong Hoang; Nguyen, Hai Truong; Hansen, Poul Erik

    2017-01-01

    An efficient and facile bismuth trifluoromethanesulfonate-catalyzed benzoylation of aromatic compounds using benzoic anhydride under solvent-free microwave irradiation has been developed. The microwave-assisted Friedel-Crafts benzoylation results in good yields within short reaction times. Bismuth...

  14. Solid State MEMS Thrusters Using Electrically Controlled Extinguishable Solid Propellant, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — ET Materials, LLC developed the first ever electrically controlled extinguishable solid propellant (ECESP). The original propellant developed under Air Force SBIR...

  15. Image based measurement techniques for aircraft propeller flow diagnostics : Propeller slipstream investigations at high-lift conditions and thrust reverse

    NARCIS (Netherlands)

    Roosenboom, E.W.M.

    2011-01-01

    The aim of the thesis is to measure the propeller slipstream properties (velocity and vorticity) and to assess the unsteady and instantaneous behavior of the propeller flow field at high disk loadings, zero thrust and thrust reverse using the image based measurement techniques. Along with its

  16. Predicting Job Crafting From the Socially Embedded Perspective: The Interactive Effect of Job Autonomy, Social Skill, and Employee Status

    OpenAIRE

    Sekiguchi, Tomoki; Li, Jie; Hosomi, Masaki

    2017-01-01

    Job crafting represents the bottom-up process of change employees make in their work boundaries and plays an important role in the management of organizational change. Following the socially embedded perspective, we examine the roles of job autonomy, social skill, and employee status in predicting job crafting. Study 1 with a sample of 509 part-time employees found that job autonomy and social skill not only directly but also interactively influenced job crafting. Study 2 with a sample of 564...

  17. Effects of a job crafting intervention program on work engagement among Japanese employees: a pretest-posttest study

    OpenAIRE

    Sakuraya, Asuka; Shimazu, Akihito; Imamura, Kotaro; Namba, Katsuyuki; Kawakami, Norito

    2016-01-01

    Abstract Background Job crafting, an employee-initiated job design/redesign, has become important for employees’ well-being such as work engagement. This study examined the effectiveness of a newly developed job crafting intervention program on work engagement (as primary outcome), as well as job crafting and psychological distress (as secondary outcomes), using a pretest-posttest study design among Japanese employees. Methods Participants were managers of a private company and a private psyc...

  18. “Making our job hospitable” – Assessment of job-crafting behavior among dental academic faculty in South India

    Directory of Open Access Journals (Sweden)

    V Siva Kalyan

    2018-01-01

    Full Text Available Introduction: Employees are regularly offered opportunities to make their work more appealing and rewarding. These opportunities might be as simple as making fine changes to their daily tasks to boost happiness and to connect with more people at vocation. Hence, an attempt is made to assess job-crafting behavior among the dental academic faculty. Materials and Methods: A cross-sectional study was conducted among dental academic faculty from five dental colleges. Job Crafting Questionnaire (JCQ was used to assess the job-crafting behavior. Mean scores were calculated for different domains of JCQ. Gender differences were analyzed using Student's “t-” test and one-way ANOVA to test the difference between different academic positions of the faculty members. Results: A total of 228 dental faculty members with a mean age of 34.43 ± 6.13 years participated in the study. The mean value of job-crafting behavior was found to be highest among female faculty (60.07 ± 8.38 and professors (61.35 ± 8.30. Male faculty scored higher in task-crafting domain and female faculty scored higher in both cognitive- and relational-crafting domains. The professors scored highest in all the three domains of job-crafting behavior as compared to that of senior lecturers and readers. Conclusion: Job crafting is an effectual workplace intervention, where employees assume an active role in shaping their work experience to enhance their job satisfaction and well-being. The overall score of job-crafting behavior was found to be highest among both professors and female faculty members. Male faculty members scored higher in task-crafting domain. With regard to individual domains, the participants scored highest in cognitive crafting followed by task and relational crafting.

  19. Different types of employee well-being across time and their relationships with job crafting.

    Science.gov (United States)

    Hakanen, Jari J; Peeters, Maria C W; Schaufeli, Wilmar B

    2018-04-01

    We used and integrated the circumplex model of affect (Russell, 1980) and the conservation of resources theory (Hobfoll, 1998) to hypothesize how various types of employee well-being, which can be differentiated on theoretical grounds (i.e., work engagement, job satisfaction, burnout, and workaholism), may differently predict various job crafting behaviors (i.e., increasing structural and social resources and challenging demands, and decreasing hindering demands) and each other over time. At Time 1, we measured employee well-being, and 4 years later at Time 2, job crafting and well-being, using a large sample of Finnish dentists (N = 1,877). The results of structural equation modeling showed that (a) work engagement positively predicted both types of increasing resources and challenging demands and negatively predicted decreasing hindering demands; (b) workaholism positively predicted increasing structural resources and challenging demands; (c) burnout positively predicted decreasing hindering demands and negatively predicted increasing structural resources, whereas (d) job satisfaction did not relate to job crafting over time; and (e) work engagement positively influenced job satisfaction and negatively influenced burnout, whereas (f) workaholism predicted burnout after controlling for baseline levels. Thus, work engagement was a stronger predictor of future job crafting and other types of employee well-being than job satisfaction. Although workaholism was positively associated with job crafting, it also predicted burnout. We conclude that the relationship between job crafting and employee well-being may be more complex than assumed, because the way in which employees will craft their jobs in the future seems to depend on how they currently feel. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  20. Leader–member exchange fosters work engagement: The mediating role of job crafting

    Directory of Open Access Journals (Sweden)

    Mirjam Radstaak

    2017-09-01

    Full Text Available Orientation: The right balance between job demands and job resources are essential for employees to bring energy and enthusiasm to work. Employees who experience high-quality relationships with their supervisors may actively craft their job demands and job resources and feel more engaged. Research purpose: The current study examined the associations between leader–member exchange (LMX, job crafting and work engagement. Motivation: This study attempts to gain more insight in the associations between LMX, job crafting and work engagement. It was hypothesised that high-quality relationships with supervisors fosters work engagement because it stimulates employees to craft their jobs by increasing social and structural job resources and challenging job demands and by decreasing hindering job demands. Research approach, design and methodology: Participants (N = 402 working for a leading mail and parcels company in the Netherlands completed questionnaires measuring LMX, work engagement and job crafting. Structural equation modelling was used to examine the hypotheses. Main findings: Increasing social job resources (β = 0.01, SE = 0.00, p < 0.001 and increasing challenging job demands (β = 0.08, SE = 0.04, p < 0.05 were significant mediators in the association between LMX and work engagement. Increasing structural job resources (β = 0.00, SE = 0.00, p = 0.92 and decreasing hindering job demands (β = -0.00, SE 0.00, p = 0.09 were not significant mediators. Practical and managerial implications: Supervisors who are capable of building high-quality relationships with their employees based on trust, respect and loyalty will foster a positive, fulfilling work-related state of mind among employees because they are more willing to proactively craft a challenging and resourceful work environment. Contribution or value-add: The findings of this study showed the importance of high-quality relationships with supervisors and were unique in examining the

  1. Crafting an International Study of Students' Conceptual Understanding of Astronomy

    Science.gov (United States)

    Slater, Stephanie; Bretones, P. S.; McKinnon, D.; Schleigh, S.; Slater, T. F.; Astronomy, Center; Education Research, Physics

    2013-01-01

    Large international investigations into the learning of science, such as the TIMSS and PISA studies, have been enlightening with regard to effective instructional practices. Data from these studies revealed weaknesses and promising practices within nations' educational systems, with evidence to suggest that these studies have led to international reforms in science education. However, these reforms have focused on the general characteristics of teaching and learning across all sciences. While extraordinarily useful, these studies have provided limited insight for any given content domain. To date, there has been no systematic effort to measure individual's conceptual astronomy understanding across the globe. This paper describes our motivations for a coordinated, multinational study of astronomy understanding. First, reformed education is based upon knowing the preexisting knowledge state of our students. The data from this study will be used to assist international astronomy education and public outreach (EPO) professionals in their efforts to improve practices across global settings. Second, while the US astronomy EPO community has a long history of activity, research has established that many practices are ineffective in the face of robust misconceptions (e.g.: seasons). Within an international sample we hope to find subpopulations that do not conform to our existing knowledge of student misconceptions, leading us to cultural or educational practices that hint at alternative, effective means of instruction. Finally, it is our hope that this first venture into large-scale disciplinary collaboration will help us to craft a set of common languages and practices, building capacity and leading toward long-term cooperation across the international EPO community. This project is sponsored and managed by the Center for Astronomy & Physics Education Research (CAPER), in collaboration with members of the International Astronomical Union-Commission 46. We are actively

  2. Relativistic Spacecraft Propelled by Directed Energy

    Science.gov (United States)

    Kulkarni, Neeraj; Lubin, Philip; Zhang, Qicheng

    2018-04-01

    Achieving relativistic flight to enable extrasolar exploration is one of the dreams of humanity and the long-term goal of our NASA Starlight program. We derive a relativistic solution for the motion of a spacecraft propelled by radiation pressure from a directed energy (DE) system. Depending on the system parameters, low-mass spacecraft can achieve relativistic speeds, thus enabling interstellar exploration. The diffraction of the DE system plays an important role and limits the maximum speed of the spacecraft. We consider “photon recycling” as a possible method to achieving higher speeds. We also discuss recent claims that our previous work on this topic is incorrect and show that these claims arise from an improper treatment of causality.

  3. Experimental research on air propellers V

    Science.gov (United States)

    Durand, W F; Lesley, E P

    1923-01-01

    In previous reports on experimental research on air propellers, by W. F. Durand and E. P. Lesley, as contained in the National Advisory Committee for Aeronautics reports nos. 14, 30, and 64, the investigations were made progressively and each without reference to results given in preceding reports and covering only information relating to forms perhaps adjacent in geometrical form and proportion. This report is a review of the entire series of results of the preceding reports with a view of examining through graphical and other appropriate means the nature of the history of the characteristics of operation as related to the systematic variations in characteristics of forms, etc., through the series of such characteristics.

  4. Space shuttle aps propellant thermal conditioner study

    Science.gov (United States)

    Fulton, D. L.

    1973-01-01

    An analytical and experimental effort was completed to evaluate a baffle type thermal conditioner for superheating O2 and H2 at supercritical pressures. The thermal conditioner consisted of a heat exchanger and an integral reactor (gas generator) operating on O2/H2 propellants. Primary emphasis was placed on the hydrogen conditioner with some effort on the oxygen conditioner and a study completed of alternate concepts for use in conditioning oxygen. A hydrogen conditioner was hot fire tested under a range of conditions to establish ignition, heat exchange and response parameters. A parallel technology task was completed to further evaluate the integral reactor and heat exchanger with the side mounted electrical spark igniter.

  5. Crusader solid propellant best technical approach

    Energy Technology Data Exchange (ETDEWEB)

    Graves, V. [Oak Ridge National Lab., TN (United States); Bader, G. [Fire Support Armament Center, Picatinny Arsenal, NJ (United States); Dolecki, M. [Tank-Automotive Research, Development, and Engineering Center, Picatinny, NJ (United States); Krupski, S. [Benet Weapons Lab., Watervliet Arsenal, NY (United States); Zangrando, R. [Close Combat Armament Center, Picatinny Arsenal, NJ (United States)

    1995-12-01

    The goal of the Solid Propellant Resupply Team is to develop Crusader system concepts capable of automatically handling 155mm projectiles and Modular Artillery Charges (MACs) based on system requirements. The system encompasses all aspects of handling from initial input into a resupply vehicle (RSV) to the final loading into the breech of the self-propelled howitzer (SPH). The team, comprised of persons from military and other government organizations, developed concepts for the overall vehicles as well as their interior handling components. An intermediate review was conducted on those components, and revised concepts were completed in May 1995. A concept evaluation was conducted on the finalized concepts, from both a systems level and a component level. The team`s Best Technical Approach (BTA) concept was selected from that evaluation. Both vehicles in the BTA have a front-engine configuration with the crew situated behind the engine-low in the vehicles. The SPH concept utilizes an automated reload port at the rear of the vehicle, centered high. The RSV transfer boom will dock with this port to allow automated ammunition transfer. The SPH rearm system utilizes fully redundant dual loaders. Active magazines are used for both projectiles and MACs. The SPH also uses a nonconventional tilted ring turret configuration to maximize the available interior volume in the vehicle. This configuration can be rearmed at any elevation angle but only at 0{degree} azimuth. The RSV configuration is similar to that of the SPH. The RSV utilizes passive storage racks with a pick-and-place manipulator for handling the projectiles and active magazines for the MACs. A telescoping transfer boom extends out the front of the vehicle over the crew and engine.

  6. Automatic Generation of the Planning Tunnel High Speed Craft Hull Form

    Institute of Scientific and Technical Information of China (English)

    Morteza Ghassabzadeh; Hassan Ghassemi

    2012-01-01

    The creation of geometric model of a ship to determine the characteristics of hydrostatic and hydrodynamic,and also for structural design and equipments arrangement are so important in the ship design process.Planning tunnel high speed craft is one of the crafts in which,achievement to their top speed is more important.These crafts with the use of tunnel have the aero-hydrodynamics properties to diminish the resistance,good sea-keeping behavior,reduce slamming and avoid porpoising.Because of the existence of the tunnel,the hull form generation of these crafts is more complex and difficult.In this paper,it has attempted to provide a method based on geometry creation guidelines and with an entry of the least control and hull form adjustment parameters,to generate automatically the hull form of planning tunnel craft.At first,the equations of mathematical model are described and subsequent,three different models generated based on present method are compared and analyzed.Obviously,the generated model has more application in the early stages of design.

  7. Job crafting and its impact on work engagement and job satisfaction in mining and manufacturing

    Directory of Open Access Journals (Sweden)

    Leon T de Beer

    2016-09-01

    Full Text Available The purpose of this study was to investigate job crafting and its relationship with work engagement and job satisfaction within the South African context. This research is important as job crafting has been shown to have a positive influence on employee motivation. A cross-sectional survey design was used to collect primary data from organisations in the mining and manufacturing industries of South Africa (N = 470. The results of multi-group structural equation modelling showed that the original four-factor structure of the job crafting scale was supported by the data, but that a three-factor structure was necessary due to a discriminant validity concern regarding two job crafting dimensions. Regression results revealed that increasing structural job resources with challenging job demands, and increasing social job resources were significant predictors of work engagement in both groups. Contrary to expectations decreasing hindering job demands was a negative predictor of job satisfaction in the mining group. Furthermore, increasing social job resources was also a significant predictor of job satisfaction in both groups. This study indicates the importance of job crafting for work engagement and job satisfaction in organisations.

  8. Alternative theoretical and methodological approaches for exploring higher education in Art and Crafts

    Directory of Open Access Journals (Sweden)

    Marte Sørebø Gulliksen

    2009-12-01

    Full Text Available This article presents and discusses approaches for exploring higher education in Art and Crafts. The concepts exploring versus research and the different foci in an insider perspective versus an outsider perspective introduces the theme. An insider perspective is said to be a useful starting point for inquiry, referring to Frayling’s trichotomy research into, research on and research through from 1993. The field of higher education in Art and Crafts education is shortly presented as comprising two main areas of knowledge: knowledge of education, and knowledge about the different subject areas within Art and Crafts. Both theory and practice are a part of these areas of knowledge. As higher education in Art and Crafts is a making profession, the most prominent challenge when exploring this today is thus said to be to develop research based knowledge on Education in Art and Crafts as a making discipline.  Two keywords are deemed to be useful in approaching this theme: Mode 2 knowledge production and transdisciplinarity. The article concludes with describing specific ways of doing this today from within the context of application. Two examples of large research projects in Scandinavia are presented as examples of such projects.

  9. A review of research in low earth orbit propellant collection

    Science.gov (United States)

    Singh, Lake A.; Walker, Mitchell L. R.

    2015-05-01

    This comprehensive review examines the efforts of previous researchers to develop concepts for propellant-collecting spacecraft, estimate the performance of these systems, and understand the physics involved. Rocket propulsion requires the spacecraft to expend two fundamental quantities: energy and propellant mass. A growing number of spacecraft collect the energy they need to execute propulsive maneuvers in-situ with solar panels. In contrast, every spacecraft using rocket propulsion has carried all of the propellant mass needed for the mission from the ground, which limits the range and mission capabilities. Numerous researchers have explored the concept of collecting propellant mass while in space. These concepts have varied in scale and complexity from chemical ramjets to fusion-driven interstellar vessels. Research into propellant-collecting concepts occurred in distinct eras. During the Cold War, concepts tended to be large, complex, and nuclear powered. After the Cold War, concepts transitioned to solar power sources and more effort has been devoted to detailed analysis of specific components of the propellant-collecting architecture. By detailing the major contributions and limitations of previous work, this review concisely presents the state-of-the-art and outlines five areas for continued research. These areas include air-compatible cathode technology, techniques to improve propellant utilization on atmospheric species, in-space compressor and liquefaction technology, improved hypersonic and hyperthermal free molecular flow inlet designs, and improved understanding of how design parameters affect system performance.

  10. Enhanced propellant performance via environmentally friendly curable surface coating

    Directory of Open Access Journals (Sweden)

    Thelma Manning

    2017-06-01

    Full Text Available Surface coating of granular propellants is widely used in a multiplicity of propellants for small, medium and large caliber ammunition. All small caliber ball propellants exhibit burning progressivity due to application of effective deterrent coatings. Large perforated propellant grains have also begun utilizing plasticizing and impregnated deterrent coatings with the purpose of increasing charge weights for greater energy and velocity for the projectile. The deterrent coating and impregnation process utilizes volatile organic compounds (VOCs and hazardous air pollutants (HAPs which results in propellants that need to be forced air dried which impacts air quality. Propellants undergo temperature fluctuations during their life. Diffusion coefficients vary exponentially with variations in temperature. A small temperature increase can induce a faster migration, even over a short period of time, which can lead to large deviations in the concentration. This large concentration change in the ammunition becomes a safety or performance liability. The presence of both polymeric deterrents and nitroglycerin(NG in the nitrocellulose matrix and organic solvents leads to higher diffusion rates. This results in continued emissions of VOCs and HAPs. Conventional polymers tend to partition within the propellant matrix. In other words, localized mixing can occur between the polymer and underlying propellant. This is due to solvent induced softening of the polymer vehicle over the propellant grain. In effect this creates a path where migration can occur. Since nitrate esters, like NG, are relatively small, it can exude to the surface and create a highly unstable and dangerous situation for the warfighter. Curable polymers do not suffer from this partitioning due to “melting” because no VOC solvents are present. They remain surface coated. The small scale characterization testing, such as closed bomb testing, small scale sensitivity, thermal stability, and

  11. Discovery Of B Ring Propellers In Cassini UVIS, And ISS

    Science.gov (United States)

    Sremcevic, Miodrag; Stewart, G. R.; Albers, N.; Esposito, L. W.

    2012-10-01

    We present evidence for the existence of propellers in Saturn's B ring by combining data from Cassini Ultraviolet Imaging Spectrograph (UVIS) and Imaging Science Subsystem (ISS) experiments. We identify two propeller populations: (1) tens of degrees wide propellers in the dense B ring core, and (2) smaller, more A ring like, propellers populating the inner B ring. The prototype of the first population is an object observed at 18 different epochs between 2005 and 2010. The ubiquitous propeller "S" shape is seen both in UVIS occultations as an optical depth depletion and in ISS as a 40 degrees wide bright stripe in unlit geometries and dark in lit geometries. Combining the available Cassini data we infer that the object is a partial gap embedded in the high optical depth region of the B ring. The gap moves at orbital speed consistent with its radial location. From the radial separation of the propeller wings we estimate that the embedded body, which causes the propeller structure, is about 1.5km in size located at a=112,921km. The UVIS occultations indicate an asymmetric propeller "S" shape. Since the object is located at an edge between high and relatively low optical depth, this asymmetry is most likely a consequence of the strong surface mass density gradient. We estimate that there are possibly dozen up to 100 other propeller objects in Saturn's B ring. The location of the discovered body, at an edge of a dense ringlet within the B ring, suggests a novel mechanism for the up to now illusive B ring irregular large-scale structure of alternating high and low optical depth ringlets. We propose that this B ring irregular structure may have its cause in the presence of many embedded bodies that shepherd the individual B ring ringlets.

  12. Prevention of Dealloying in Manganese Aluminium Bronze Propeller: Part II

    Directory of Open Access Journals (Sweden)

    Napachat Tareelap

    2014-03-01

    Full Text Available Due to the failure of manganese aluminium bronze (MAB propeller caused by dealloying corrosion as described in Part I [1], this work aims to study the prevention of dealloying corrosion using aluminium and zinc sacrificial anodes. The results indicated that both of the sacrificial anodes could prevent the propeller from dealloying. Moreover, the dealloying in seawater was less than that found in brackish water. It was possible that hydroxide ions, from cathodic reaction, reacted with calcium in seawater to form calcium carbonate film protecting the propeller from corrosion.

  13. ARKTOS amphibious oil spill response craft for mixed ice/water conditions

    Energy Technology Data Exchange (ETDEWEB)

    Seligman, Bruce H.J.W. [ARKTOS International S.A., Tavannes (Switzerland)], email: bruce.seligman@arktoscraft.com; Hall, T.A. [Hall Marine Design Ltd., Vancouver B.C. (Canada)], email: thallhmd@telus.net

    2010-07-01

    The oil spill which occurred recently in the Gulf of Mexico highlighted the lack of efficient oil spill clean-up equipment for an offshore environment. With the increase in industrial operations in the Arctic Seas it is of high importance to develop an efficient oil spill response as the absence of reliable oil spill contingency plans will not be tolerated in such environmentally sensitive areas. The aim of this paper is to present the use of the ARKTOS amphibious craft for cleaning up an oil spill in the Arctic. This craft is usually used for logistical services and evacuation purposes; its use for clean-up purposes has been under study since 2000. This study showed that the ARKTOS craft could be an efficient means for oil spill clean-up in the Arctic because of its proven ice capable amphibious platforms and its hydraulic power; however oil collection trials should be performed to validate it.

  14. Continual Online Evolutionary Planning for In-Game Build Order Adaptation in StarCraft

    DEFF Research Database (Denmark)

    Justesen, Niels Orsleff; Risi, Sebastian

    2017-01-01

    able to switch between predefined strategies, which makes it hard to adapt to new situations. This paper introduces an evolutionary-based method to overcome this challenge, called Continual Online Evolutionary Planning (COEP), which is able to perform in-game adaptive build-order planning. COEP......The real-time strategy game StarCraft has become an important benchmark for AI research as it poses a complex environment with numerous challenges. An important strategic aspect in this game is to decide what buildings and units to produce. StarCraft bots playing in AI competitions today are only...... was added to an open source StarCraft bot called UAlbertaBot and is able to outperform the built-in bots in the game as well as being competitive against a number of scripted opening strategies. The COEP augmented bot can change its build order dynamically and quickly adapt to the opponent’s strategy....

  15. ARKTOS amphibious oil spill response craft for mixed ice/water conditions

    International Nuclear Information System (INIS)

    Seligman, Bruce H.J.W.; Hall, T.A.

    2010-01-01

    The oil spill which occurred recently in the Gulf of Mexico highlighted the lack of efficient oil spill clean-up equipment for an offshore environment. With the increase in industrial operations in the Arctic Seas it is of high importance to develop an efficient oil spill response as the absence of reliable oil spill contingency plans will not be tolerated in such environmentally sensitive areas. The aim of this paper is to present the use of the ARKTOS amphibious craft for cleaning up an oil spill in the Arctic. This craft is usually used for logistical services and evacuation purposes; its use for clean-up purposes has been under study since 2000. This study showed that the ARKTOS craft could be an efficient means for oil spill clean-up in the Arctic because of its proven ice capable amphibious platforms and its hydraulic power; however oil collection trials should be performed to validate it.

  16. Poly(vinyl chloride-grafted multi-walled carbon nanotubes via Friedel-Crafts alkylation

    Directory of Open Access Journals (Sweden)

    2010-11-01

    Full Text Available A novel approach was developed for the surface modification of the multi-walled carbon nanotubes (MWCNTs with high percentage of grafting (PG% by the grafting of polymer via the Friedel-Crafts alkylation. The graft reaction conditions, such as the amount of catalyst added, the reaction temperature, and the reaction time were optimized for the Friedel-Crafts alkylation of the MWCNTs with poly(vinyl chloride (PVC with anhydrous aluminum chloride (AlCl3 as catalyst in chloroform (CHCl3. The Fourier Transform Infrared (FT-IR, Raman, and thermogravimetric (TGA analysis showed that PVC had been successfully grafted onto MWCNTs both at the ends and on the sidewalls by the proposed Friedel-Crafts alkylation. The PVC grafted MWCNTs (PVC-MWCNTs could be dispersed well in organic solvent and the dispersion was more stable.

  17. Ignition and combustion characteristics of metallized propellants

    Science.gov (United States)

    Turns, Stephen R.; Mueller, D. C.

    1993-01-01

    Experimental and analytical investigations focusing on secondary atomization and ignition characteristics of aluminum/liquid hydrocarbon slurry propellants were conducted. Experimental efforts included the application of a laser-based, two-color, forward-scatter technique to simultaneously measure free-flying slurry droplet diameters and velocities for droplet diameters in the range of 10-200 microns. A multi-diffusion flame burner was used to create a high-temperature environment into which a dilute stream of slurry droplets could be introduced. Narrowband measurements of radiant emission were used to determine if ignition of the aluminum in the slurry droplet had occurred. Models of slurry droplet shell formation were applied to aluminum/liquid hydrocarbon propellants and used to ascertain the effects of solids loading and ultimate particle size on the minimum droplet diameter that will permit secondary atomization. For a 60 weight-percent Al slurry, the limiting critical diameter was predicted to be 34.7 microns which is somewhat greater than the 20-25 micron limiting diameters determined in the experiments. A previously developed model of aluminum ignition in a slurry droplet was applied to the present experiments and found to predict ignition times in reasonable agreement with experimental measurements. A model was also developed that predicts the mechanical stress in the droplet shell and a parametric study was conducted. A one-dimensional model of a slurry-fueled rocket combustion chamber was developed. This model includes the processes of liquid hydrocarbon burnout, secondary atomization, aluminum ignition, and aluminum combustion. Also included is a model for radiant heat transfer from the hot aluminum oxide particles to the chamber walls. Exercising this model shows that only a modest amount of secondary atomization is required to reduce residence times for aluminum burnout, and thereby maintain relatively short chamber lengths. The model also predicts

  18. How Valuable is a Well-Crafted Design and Name Brand?

    DEFF Research Database (Denmark)

    Kristensen, Tore; Gabrielsen, Gorm; Zaichkowsky, Judith

    2012-01-01

    Preferences for similarly designed consumer products, evaluated blind and branded and also with and without prices, were tested in a consumer setting. The consumer's perceptual experience led to preference of the well-crafted high-priced option. This preference was enhanced by priming consumers w...... of choices using measures of inherent design acumen, prior experience, and purchasing behavior were largely unsuccessful.......Preferences for similarly designed consumer products, evaluated blind and branded and also with and without prices, were tested in a consumer setting. The consumer's perceptual experience led to preference of the well-crafted high-priced option. This preference was enhanced by priming consumers...

  19. Two-craft Coulomb formation study about circular orbits and libration points

    Science.gov (United States)

    Inampudi, Ravi Kishore

    This dissertation investigates the dynamics and control of a two-craft Coulomb formation in circular orbits and at libration points; it addresses relative equilibria, stability and optimal reconfigurations of such formations. The relative equilibria of a two-craft tether formation connected by line-of-sight elastic forces moving in circular orbits and at libration points are investigated. In circular Earth orbits and Earth-Moon libration points, the radial, along-track, and orbit normal great circle equilibria conditions are found. An example of modeling the tether force using Coulomb force is discussed. Furthermore, the non-great-circle equilibria conditions for a two-spacecraft tether structure in circular Earth orbit and at collinear libration points are developed. Then the linearized dynamics and stability analysis of a 2-craft Coulomb formation at Earth-Moon libration points are studied. For orbit-radial equilibrium, Coulomb forces control the relative distance between the two satellites. The gravity gradient torques on the formation due to the two planets help stabilize the formation. Similar analysis is performed for along-track and orbit-normal relative equilibrium configurations. Where necessary, the craft use a hybrid thrusting-electrostatic actuation system. The two-craft dynamics at the libration points provide a general framework with circular Earth orbit dynamics forming a special case. In the presence of differential solar drag perturbations, a Lyapunov feedback controller is designed to stabilize a radial equilibrium, two-craft Coulomb formation at collinear libration points. The second part of the thesis investigates optimal reconfigurations of two-craft Coulomb formations in circular Earth orbits by applying nonlinear optimal control techniques. The objective of these reconfigurations is to maneuver the two-craft formation between two charged equilibria configurations. The reconfiguration of spacecraft is posed as an optimization problem using the

  20. Craft villages and tourism development, a case study in Phu Quoc island of Vietnam

    Directory of Open Access Journals (Sweden)

    Hieu Vu Minh

    2017-05-01

    Full Text Available Craft tourism is attracting many domestic and foreign tourists. In recent years in Vietnam, craft villages have exploited their potentials in tourism industry. For many different causes, tourism activities have yet reached expectations and their potentials for tourism development. This paper is to review their currents, tourism potentials and limitations and then formulate recommendations to the tourism development in Phu Quoc island. The data for this paper are from two sources. Secondary data were collected from the vast literature and journals. Primary data were from interviews with village owners, related authorities, tourists, tourism corporate, etc. and results serve as guidelines to develop the tourism industry and management.

  1. Advanced Insulation Materials for Cryogenic Propellant Storage Applications, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Advanced Materials Technology, Inc responds to the NASA solicitation Topic X9 entitled "Propulsion and Propellant Storage" under subtopic X9-01, "Long Term Cryogenic...

  2. Propellant Flow Actuated Piezoelectric Rocket Engine Igniter, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Spark ignition of a bi-propellant rocket engine is a classic, proven, and generally reliable process. However, timing can be critical, and the control logic,...

  3. Propellant Flow Actuated Piezoelectric Rocket Engine Igniter, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Under a Phase 1 effort, IES successfully developed and demonstrated a spark ignition concept where propellant flow drives a very simple fluid mechanical oscillator...

  4. Dynamical Model of Rocket Propellant Loading with Liquid Hydrogen

    Data.gov (United States)

    National Aeronautics and Space Administration — A dynamical model describing the multi-stage process of rocket propellant loading has been developed. It accounts for both the nominal and faulty regimes of...

  5. Gun barrel erosion - Comparison of conventional and LOVA gun propellants

    NARCIS (Netherlands)

    Hordijk, A.C.; Leurs, O.

    2006-01-01

    The research department Energetic Materials within TNO Defence, Security and Safety is involved in the development and (safety and insensitive munitions) testing of conventional (nitro cellulose based) and thermoplastic elastomer (TPE) based gun propellants. Recently our testing capabilities have

  6. Feasibility Study on Cutting HTPB Propellants with Abrasive Water Jet

    Science.gov (United States)

    Jiang, Dayong; Bai, Yun

    2018-01-01

    Abrasive water jet is used to carry out the experiment research on cutting HTPB propellants with three components, which will provide technical support for the engineering treatment of waste rocket motor. Based on the reliability theory and related scientific research results, the safety and efficiency of cutting sensitive HTPB propellants by abrasive water jet were experimentally studied. The results show that the safety reliability is not less than 99.52% at 90% confidence level, so the safety is adequately ensured. The cooling and anti-friction effect of high-speed water jet is the decisive factor to suppress the detonation of HTPB propellant. Compared with pure water jet, cutting efficiency was increased by 5% - 87%. The study shows that abrasive water jets meet the practical use for cutting HTPB propellants.

  7. Propellant Preparation Laboratory Complex (Area1-21)

    Data.gov (United States)

    Federal Laboratory Consortium — Description: Area 1-21 is an explosion resistant complex of nine cells built into the side of a granite ridge. Three solid propellant cutting cells are housed in the...

  8. Particle swarm optimization: an alternative in marine propeller optimization?

    Science.gov (United States)

    Vesting, F.; Bensow, R. E.

    2018-01-01

    This article deals with improving and evaluating the performance of two evolutionary algorithm approaches for automated engineering design optimization. Here a marine propeller design with constraints on cavitation nuisance is the intended application. For this purpose, the particle swarm optimization (PSO) algorithm is adapted for multi-objective optimization and constraint handling for use in propeller design. Three PSO algorithms are developed and tested for the optimization of four commercial propeller designs for different ship types. The results are evaluated by interrogating the generation medians and the Pareto front development. The same propellers are also optimized utilizing the well established NSGA-II genetic algorithm to provide benchmark results. The authors' PSO algorithms deliver comparable results to NSGA-II, but converge earlier and enhance the solution in terms of constraints violation.

  9. Model-based Diagnostics for Propellant Loading Systems

    Data.gov (United States)

    National Aeronautics and Space Administration — The loading of spacecraft propellants is a complex, risky operation. Therefore, diagnostic solutions are neces- sary to quickly identify when a fault occurs, so that...

  10. AN AIRPLANE WITH UNCONVENTIONALLY PLACED PROPELLER POWER UNIT

    Directory of Open Access Journals (Sweden)

    Jan Červinka

    2017-02-01

    Full Text Available The significance of the influence of operating propellers on the aircraft aerodynamic characteristics is well-known. Wind tunnel testing of an airplane model with operating propellers is a complex task regarding the required similarity of the full-scale and the model case. Matching sufficient similarity in axial and rotational velocities in the propeller slipstream is the primordial condition for the global aerodynamic similarity of the windtunnel testing. An example of the model power units with related devices is presented. Examples of the wind tunnel testing results illustrate the extent of the propeller influence on aerodynamic characteristics of an aircraft of unconventional configuration with power units positioned at the fuselage afterbody.

  11. Numerical Prediction of Hydromechanical Behaviour of Controllable Pitch Propeller

    Directory of Open Access Journals (Sweden)

    Saman Tarbiat

    2014-01-01

    Full Text Available The research described in this paper was carried out to predict hydrodynamic and frictional forces of controllable pitch propeller (CPP that bring about fretting problems in a blade bearing. The governing equations are Reynolds-averaged Navier-Stokes (RANS and are solved by OpenFOAM solver for hydrodynamic forces behind the ship’s wake. Frictional forces are calculated by practical mechanical formulae. Different advance velocities with constant rotational speed for blades are used to achieve hydrodynamic coefficients in open water and the wake behind the propeller. Results are compared at four different pitches. Detailed numerical results of 3D modelling of the propeller, hydrodynamic characteristics, and probability of the fretting motion in the propeller are presented. Results show that the probability of the fretting movement is related to the pitch.

  12. An Additively Manufactured Torch Igniter for Liquid Propellants

    Data.gov (United States)

    National Aeronautics and Space Administration — Consistent and reliable rocket engine ignition has yet to be proven through an additively manufactured torch igniter for liquid propellants. The coupling of additive...

  13. 78 FR 52872 - Airworthiness Directives; 328 Support Services GmbH (Type Certificate Previously Held by AvCraft...

    Science.gov (United States)

    2013-08-27

    ... Services GmbH (Type Certificate Previously Held by AvCraft Aerospace GmbH; Fairchild Dornier GmbH; Dornier... certain 328 Support Services GmbH (Type Certificate Previously Held by AvCraft Aerospace GmbH; Fairchild... send any written relevant data, views, or arguments about this proposed AD. Send your comments to an...

  14. Regular versus cutback-related change: the role of employee job crafting in organizational change contexts of different nature

    NARCIS (Netherlands)

    Petrou, P.; Demerouti, E.; Xanthopoulou, D.

    2017-01-01

    The present study addresses how job characteristics (e.g., autonomy, workload, and their interaction) relate to employee job crafting (i.e., seeking resources, seeking challenges, and reducing demands), and whether job crafting relates to employee work-related well-being (i.e., work engagement and

  15. Synthesis of 1-indanones through the intramolecular Friedel-Crafts acylation reaction using NbCl5 as Lewis acid

    International Nuclear Information System (INIS)

    Polo, Ellen Christine; Silva-Filho, Luiz Carlos da; Silva, Gil Valdo Jose da; Constantino, Mauricio Gomes

    2008-01-01

    The intramolecular Friedel-Crafts acylation reaction of 3-arylpropanoic acids to give 1-indanones can be effected in good yields under mild conditions (room temperature) by using niobium pentachloride. Our results indicate that NbCl 5 acts both as reagent (to transform carboxylic acids into acyl chlorides) and as catalyst in the Friedel-Crafts cyclization. (author)

  16. The influence of future time perspective on work engagement and job performance: the role of job crafting.

    NARCIS (Netherlands)

    Kooij, T.A.M.; Tims,; Akkermans,

    2017-01-01

    This two-wave study aimed to examine future time perspective (FTP) as an antecedent of job crafting, and in turn job crafting as a mediator in associations between FTP and work outcomes. Based on the lifespan socio-emotional selectivity theory, we expected that open-ended and limited FTP would evoke

  17. Designing Small Propellers for Optimum Efficiency and Low Noise Footprint

    Science.gov (United States)

    2015-06-26

    each one. The GUI contains input boxes for all of the necessary data in order to run QMIL, QPROP, NAFNoise, and to produce Visual Basic ( VBA ) code... VBA macros that will automatically place reference planes for each airfoil section and insert the splined airfoils to their respective reference...Figure 24. Solid propeller exa mple. Figure 25. Hub and spoke propeller design. Figure 26. Alumninum hub design. accessed on May 12, 2015. DC, August

  18. A fractional calculus perspective of distributed propeller design

    Science.gov (United States)

    Tenreiro Machado, J.; Galhano, Alexandra M.

    2018-02-01

    A new generation of aircraft with distributed propellers leads to operational performances superior to those exhibited by standard designs. Computational simulations and experimental tests show a reduction of fuel consumption and noise. This paper proposes an analogy between aerodynamics and electrical circuits. The model reveals properties similar to those of fractional-order systems and gives a deeper insight into the dynamics of multi-propeller coupling.

  19. Cryogenic Propellant Storage and Transfer Engineering Development Unit Hydrogen Tank

    Science.gov (United States)

    Werkheiser, Arthur

    2015-01-01

    The Cryogenic Propellant Storage and Transfer (CPST) project has been a long-running program in the Space Technology Mission Directorate to enhance the knowledge and technology related to handling cryogenic propellants, specifically liquid hydrogen. This particular effort, the CPST engineering development unit (EDU), was a proof of manufacturability effort in support of a flight article. The EDU was built to find and overcome issues related to manufacturability and collect data to anchor the thermal models for use on the flight design.

  20. Integral performance optimum design for multistage solid propellant rocket motors

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hongtao (Shaanxi Power Machinery Institute (China))

    1989-04-01

    A mathematical model for integral performance optimization of multistage solid propellant rocket motors is presented. A calculation on a three-stage, volume-fixed, solid propellant rocket motor is used as an example. It is shown that the velocity at burnout of intermediate-range or long-range ballistic missile calculated using this model is four percent greater than that using the usual empirical method.

  1. PIV-based load determination in aircraft propellers

    OpenAIRE

    Ragni, D.

    2012-01-01

    The thesis describes the application of particle image velocimetry (PIV) to study the aerodynamic loads of airfoils and aircraft propellers. The experimental work focuses on the development of a measurement procedure to infer the pressure of the flow field from the velocity distribution obtained by PIV velocimetry. The technique offers important advantages in aircraft propellers, since the loads can be locally inspected without the need to install pressure sensors and momentum balances in rot...

  2. Study on Combustion Characteristics and Propelling Projectile Motion Process of Bulk-Loaded Liquid Propellant

    Science.gov (United States)

    Xue, Xiaochun; Yu, Yonggang; Mang, Shanshan

    2017-07-01

    Data are presented showing that the problem of gas-liquid interaction instability is an important subject in the combustion and the propellant projectile motion process of a bulk-loaded liquid propellant gun (BLPG). The instabilities themselves arise from the sources, including fluid motion, to form a combustion gas cavity called Taylor cavity, fluid turbulence and breakup caused by liquid motion relative to the combustion chamber walls, and liquid surface breakup arising from a velocity mismatch on the gas-liquid interface. Typically, small disturbances that arise early in the BLPG combustion interior ballistic cycle can become amplified in the absence of burn rate limiting characteristics. Herein, significant attention has been given to developing and emphasizing the need for better combustion repeatability in the BLPG. Based on this goal, the concept of using different geometries of the combustion chamber is introduced and the concept of using a stepped-wall structure on the combustion chamber itself as a useful means of exerting boundary control on the combustion evolution to thus restrain the combustion instability has been verified experimentally in this work. Moreover, based on this background, the numerical simulation is devoted to a special combustion issue under transient high-pressure and high-temperature conditions, namely, studying the combustion mechanism in a stepped-wall combustion chamber with full monopropellant on one end that is stationary and the other end can move at high speed. The numerical results also show that the burning surface of the liquid propellant can be defined geometrically and combustion is well behaved as ignition and combustion progressivity are in a suitable range during each stage in this combustion chamber with a stepped-wall structure.

  3. Low-Cost Propellant Launch to LEO from a Tethered Balloon - 'Propulsion Depots' Not 'Propellant Depots'

    Science.gov (United States)

    Wilcox, Brian H.; Schneider, Evan G.; Vaughan, David A.; Hall, Jeffrey L.; Yu, Chi Yau

    2011-01-01

    As we have previously reported, it may be possible to launch payloads into low-Earth orbit (LEO) at a per-kilogram cost that is one to two orders of magnitude lower than current launch systems, using only a relatively small capital investment (comparable to a single large present-day launch). An attractive payload would be large quantities of high-performance chemical rocket propellant (e.g. Liquid Oxygen/Liquid Hydrogen (LO2/LH2)) that would greatly facilitate, if not enable, extensive exploration of the moon, Mars, and beyond.

  4. LNG systems for natural gas propelled ships

    Science.gov (United States)

    Chorowski, M.; Duda, P.; Polinski, J.; Skrzypacz, J.

    2015-12-01

    In order to reduce the atmospheric pollution generated by ships, the International Marine Organization has established Emission Controlled Areas. In these areas, nitrogen oxides, sulphur oxides and particulates emission is strongly controlled. From the beginning of 2015, the ECA covers waters 200 nautical miles from the coast of the US and Canada, the US Caribbean Sea area, the Baltic Sea, the North Sea and the English Channel. From the beginning of 2020, strong emission restrictions will also be in force outside the ECA. This requires newly constructed ships to be either equipped with exhaust gas cleaning devices or propelled with emission free fuels. In comparison to low sulphur Marine Diesel and Marine Gas Oil, LNG is a competitive fuel, both from a technical and economical point of view. LNG can be stored in vacuum insulated tanks fulfilling the difficult requirements of marine regulations. LNG must be vaporized and pressurized to the pressure which is compatible with the engine requirements (usually a few bar). The boil-off must be controlled to avoid the occasional gas release to the atmosphere. This paper presents an LNG system designed and commissioned for a Baltic Sea ferry. The specific technical features and exploitation parameters of the system will be presented. The impact of strict marine regulations on the system's thermo-mechanical construction and its performance will be discussed. The review of possible flow-schemes of LNG marine systems will be presented with respect to the system's cost, maintenance, and reliability.

  5. WOW: light print, light propel, light point

    Science.gov (United States)

    Glückstad, Jesper; Bañas, Andrew; Aabo, Thomas; Palima, Darwin

    2012-10-01

    We are presenting so-called Wave-guided Optical Waveguides (WOWs) fabricated by two-photon polymerization and capable of being optically manipulated into any arbitrary orientation. By integrating optical waveguides into the structures we have created freestanding waveguides which can be positioned anywhere in a sample at any orientation using real-time 3D optical micromanipulation with six degrees of freedom. One of the key aspects of our demonstrated WOWs is the change in direction of in-coupled light and the marked increase in numerical aperture of the out-coupled light. Hence, each light propelled WOW can tap from a relatively broad incident beam and generate a much more tightly confined light at its tip. The presentation contains both numerical simulations related to the propagation of light through a WOW and preliminary experimental demonstrations on our BioPhotonics Workstation. In a broader context, this research shows that optically trapped micro-fabricated structures can potentially help bridge the diffraction barrier. This structure-mediated paradigm may be carried forward to open new possibilities for exploiting beams from far-field optics down to the sub-wavelength domain.

  6. Stereospecific Winding of Polycyclic Aromatic Hydrocarbons into Trinacria Propellers.

    Science.gov (United States)

    Mosca, Dario; Stopin, Antoine; Wouters, Johan; Demitri, Nicola; Bonifazi, Davide

    2017-11-02

    The stereospecific trimerization of enantiomerically pure binaphthols with hexakis(bromomethyl)benzene gives access in one step to enantiomerically pure molecular propellers, in which three binaphthyl rings are held together with dioxecine rings. X-ray diffraction analysis revealed that three out the six naphthyl moieties are folded in a (EF) 3 -type arrangement held by three intramolecular C-H⋅⋅⋅π interactions. This slips outward the three remaining naphthyl rings in a blade-like fashion, just like in three-folded propeller components. This peculiar conformation shows striking similarity to the mythological Sicilian symbol of Trinacria, from which the name "trinacria propeller" derives. The propeller conformation is also preserved in chlorinated solutions, as displayed by the presence of a peak at 4.7 ppm typical of an aromatic proton resonance engaged in a C-H⋅⋅⋅π interaction. The denaturation of the propeller-like conformation is obtained at high temperature, corresponding to activation energy for the ring inversion of ca. 18.2 kcal mol -1 . Notably, halide-functionalized molecular propellers exposing I-atoms at the leading and trailing edges could be prepared stereo- and regiospecifically by choosing the relevant iodo-bearing BINOL derivative. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Numerical study of hub taper angle on podded propeller performance

    International Nuclear Information System (INIS)

    Islam, M.F.; Veitch, B.; Bose, N.; Liu, P.

    2005-01-01

    Presently, the majority of podded propulsion systems are of the pulling type, because this type provides better hydrodynamic efficiency than the pushing type. There are several possible explanations for the better overall performance of a puller type podded propulsor. One is related to the difference in hub shape. Puller and pusher propellers have opposite hub taper angles, hence different hub and blade root shape. These differences cause changes in the flow condition and possibly influence the overall performance. The current study focuses on the variation in performance of pusher and puller propellers with the same blade sections, but different hub taper angles. A hyperboloidal low order source doublet steady/unsteady time domain panel method code was modified and used to evaluate effects of hub taper angle on the open water propulsive performance of some fixed pitch screw propellers used in podded propulsion systems. The modified code was first validated against measurements of two model propellers in terms of average propulsive performance and good agreement was found. Major findings include significant effects of hub taper angle on propulsive performance of tapered hub propellers and noticeable effects of hub taper angle on sectional pressure distributions of tapered hub propeller blades. (author)

  8. Effects of superhydrophobic surface on the propeller wake

    Science.gov (United States)

    Choi, Hongseok; Lee, Jungjin; Park, Hyungmin

    2017-11-01

    This study investigates the change in propeller wake when the superhydrophobic surface is applied on the propeller blade. The propeller rotates in a quiescent water tank, facing its bottom, with a rotational Reynolds number of 96000. To measure the three-dimensional flow fields, we use stereo PIV and a water prism is installed at the camera-side tank wall. Two cameras are tilted 30 degrees from the normal axis of the tank wall, satisfying schiempflug condition. Superhydrophobic surface is made by coating hydrophobic nanoparticles on the propeller blade. Measurements are done on two vertical planes (at the center of propeller hub and the blade tip), and are ensemble averaged being classified by blade phase of 0 and 90 degrees. Velocity fluctuation, turbulent kinetic energy, and vorticity are evaluated. With superhydrophobic surface, it is found that the turbulence level is significantly (20 - 30 %) reduced with a small penalty (less than 5%) in the streamwise momentum (i.e., thrust) generation. This is because the cone shaped propeller wake gets narrower and organized vortex structures are broken with the superhydrophobic surfaces. More detailed flow analysis will be given. Supported by NRF (NRF-2016R1C1B2012775, NRF-2016M2B2A9A02945068) programs of Korea government.

  9. Studies of pellet acceleration with arc discharge heated propellants

    International Nuclear Information System (INIS)

    Schuresko, D.D.

    1986-01-01

    An arc discharge has been utilized to heat gaseous propellants in a pneumatic pellet gun. A cylindrical arc chamber is interposed between the propellant inlet valve and the gun breech and fitted with a ceramic insert for generating swirl in the incoming gas stream. The arc is initiated after the propellant valve opens and the breech pressure starts to rise; a typical discharge lasts 300 microseconds with peak currents up to 2 kA at arc voltages ranging from 100-400 V. The system is instrumented with piezoelectric pressure transducers at the propellant valve outlet, gun breech, and gun muzzle. The gun has been operated with 4 mm diameter polyurethane foam pellets (density = 0.14 g/cm 3 ), a 40 cm-long barrel, and various gas propellants at pressures exceeding 70 bar. At I/sub arc/ = 1 kA, V/sub arc/ = 200 V, with helium propellant, the arc produces a 2-3 fold prompt increase in P/sub breech/ and a delayed increase in P/sub muzzle/; the pellets exit the gun from 0.5-1.0 ms earlier than with the gas alone at 40% higher speeds. Comparisons with the so-called ideal gun theory and with full one-dimensional hydrodynamic calculations of the pellet acceleration will be presented

  10. Studies of pellet acceleration with arc discharge heated propellants

    International Nuclear Information System (INIS)

    Schuresko, D.D.

    1985-01-01

    An arc discharge has been utilized to heat gaseous propellants in a pneumatic pellet gun. A cylindrical arc chamber is interposed between the propellant inlet valve and the gun breech and fitted with a ceramic insert for generating swirl in the incoming gas stream. The arc is initiated after the propellant valve opens and the breech pressure starts to rise; a typical discharge lasts 300 microseconds with peak currents u to 2 kA at arc voltages ranging from 100 to 400 V. The system is instrumented with piezoelectric pressure transducers at the propellant valve outlet, gun breech, and gun muzzle. The gun has been operated with 4 mm diameter polyurethane foam pellets (density = 0.14 g/cm 3 ), a 40 cm-long barrel, and various gas propellants at pressures exceeding 70 bar. At I/sub arc/ = 1 kA, V/sub arc/ = 200 V, with helium propellant, the arc produces a 2 to 3 fold prompt increase in P/sub breech/ and a delayed increase in P/sub muzzle/; the pellets exit the gun from 0.5 to 1.0 ms earlier than with the gas alone at 40% higher speeds. Comparisons with the so-called ideal gun theory and with full one-dimensional hydrodynamic calculations of the pellet acceleration will be presented

  11. A Simple Method for High-Lift Propeller Conceptual Design

    Science.gov (United States)

    Patterson, Michael; Borer, Nick; German, Brian

    2016-01-01

    In this paper, we present a simple method for designing propellers that are placed upstream of the leading edge of a wing in order to augment lift. Because the primary purpose of these "high-lift propellers" is to increase lift rather than produce thrust, these props are best viewed as a form of high-lift device; consequently, they should be designed differently than traditional propellers. We present a theory that describes how these props can be designed to provide a relatively uniform axial velocity increase, which is hypothesized to be advantageous for lift augmentation based on a literature survey. Computational modeling indicates that such propellers can generate the same average induced axial velocity while consuming less power and producing less thrust than conventional propeller designs. For an example problem based on specifications for NASA's Scalable Convergent Electric Propulsion Technology and Operations Research (SCEPTOR) flight demonstrator, a propeller designed with the new method requires approximately 15% less power and produces approximately 11% less thrust than one designed for minimum induced loss. Higher-order modeling and/or wind tunnel testing are needed to verify the predicted performance.

  12. Primary student teachers’ perceptions of their prior experiences with craft-making in light of Hannah Arendt’s human condition

    Directory of Open Access Journals (Sweden)

    Seija Karppinen

    2013-09-01

    Full Text Available This article presents the results of a study about student teachers’ feelings toward craft-making and teaching crafts. As a teacher educator in teacher training, my interest lies first in student teachers’ prior craft experiences and in their prejudices about themselves as craft-makers in relation to the human condition as set forth by philosopher Hannah Arendt (1958/2002. Second, I am interested in how students’ experiences and their image of crafts affect their attitude to crafts and teaching crafts. The study uses qualitative content analysis (e.g. Cohen, Manion & Morrison, 2007, concept clarification (e.g. Kramer, 1993; Burkin, 2011 and thought experiments (Zalta, 2011; Cohnitz, 2006; Sorensen, 1992 to identify and categorise student teachers’ emotional experiences. The data consist of essays (craft biographies, N=144 by first-year student teachers which were written in 2008 and 2009 during a basic course in crafts as part of teacher education at the University of Helsinki. Arendt (1958/2002 labelled the elements of the human condition as labour, work and action. In this study I discuss how, for instance, Arendtian concepts could be explained in relation to crafts, craft-making and education. Arendt categorises craft, defined as things made by hand, as part of the concept of work. In this study, I consider whether crafts and craft-making could be part of other Arendtian terms as well and how these terms fit various educational situations. As a result, there is a need for additional terms alongside Arendtian terms to describe multifaceted craft-making and primary student teachers’ perceptions of themselves as craft-makers. In relation to student teachers’ memories on primary school crafts, I have labelled Arendtian concept labour as students’ credit-orientated activity, the concept of work as making-orientated activity and the concept of action as interaction-orientated activity. These three orientations of craft frame student

  13. Scholarisation, Apprenticeship and Social Differentiation. Analysis of the Non-Industrial Craft Sector in Morocco

    Science.gov (United States)

    Gerard, Etienne

    2012-01-01

    The article approaches the question of the schooling processes in the particular environment of the Moroccan craftsmen of Fez. It shows that the weak schooling of the children is bound to the representations and to the ways of transmission of craft industry knowledge. Schooling is, indeed, the object of tensions between a school system of western…

  14. Trait-level and week-level regulatory focus as a motivation to craft a job

    NARCIS (Netherlands)

    Petrou, P.; Demerouti, E.

    2015-01-01

    Purpose – The purpose of this paper is to address regulatory focus (promotion vs prevention) as a trait-level variable and a week-level variable linked to employee job crafting behaviors (i.e. seeking resources, seeking challenges and reducing demands). The authors hypothesized that while promotion

  15. Automatic Observer Script for StarCraft: Brood War Bot Games (technical report)

    OpenAIRE

    Mattsson, Björn Persson; Vajda, Tomáš; Čertický, Michal

    2015-01-01

    This short report describes an automated BWAPI-based script developed for live streams of a StarCraft Brood War bot tournament, SSCAIT. The script controls the in-game camera in order to follow the relevant events and improve the viewer experience. We enumerate its novel features and provide a few implementation notes.

  16. Fatigue resistance of welded joints in aluminium high-speed craft : A total stress concept

    NARCIS (Netherlands)

    Den Besten, J.H.

    2015-01-01

    Crew transfers, surveillance duties and {security, rescue, interception} operations at sea typically require high-speed craft. Aluminium is quite often selected as hull structure material because of its weight save potential in comparison to steel. The fatigue strength, however, may become a point

  17. The river and the people. An approach to memories, craft and adult education

    Directory of Open Access Journals (Sweden)

    Emilio Lucio-Villegas

    2018-04-01

    Full Text Available The main aim of this article is to describe an ongoing study to recover the memories of the people and the traditional crafts associated with the Guadalquivir River where it passes through a town called C., 12km from the city of S. in the south of Spain. It seems that people are losing their sense of belonging to both a symbolic and geographical territory. The process for recovering it can be considered a generator of experiences and learning. These experiences are related to identity as an element which enables people to understand how individuals establish relationships amongst themselves and with the environment. The paper describes the process of research based on interviewing people to capture their experiences. This is a work in process. The first outcomes are related to a number of descriptive categories such as: the crafts associated with the River; the use of the River to transport goods and people; the family ties associated with the crafts; the cosmopolitanism of the people and the changes ensuing from it; the role of women; and the River as a magical and mysterious place. Preliminary conclusions call on us to consider the importance of recovering traditional crafts as a source of adult education, and of maintaining a cultural identity threatened by globalisation processes.

  18. Traditional Craft or Technology Education: Development of Students' Technical Abilities in Finnish Comprehensive School

    Science.gov (United States)

    Autio, Ossi

    2016-01-01

    Changes in the economy, nature, production and society together with increasing scientific and technological knowledge make demands of transforming school teaching in the field of technology education. The aim of the article is briefly to explore the integration between science, technology and traditional craft education by analyzing the current…

  19. 25 CFR 141.27 - Trade in imitation Indian crafts prohibited.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Trade in imitation Indian crafts prohibited. 141.27 Section 141.27 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR FINANCIAL ACTIVITIES BUSINESS PRACTICES ON THE NAVAJO, HOPI AND ZUNI RESERVATIONS General Business Practices § 141.27 Trade in imitation...

  20. Job crafting and performance of Dutch and American health care professionals

    NARCIS (Netherlands)

    Gordon, H.J.; Demerouti, E.; Le Blanc, P.M.; Bipp, T.

    2015-01-01

    We explore how job demands and job resources are related to job crafting, and how this, in turn, is related to performance in two samples of American (US; N = 70) and Dutch (NL; N = 144) health care professionals (HCP). A cross-sectional, cross-cultural design revealed that US HCP have higher job

  1. The Functions and Benefits of the ePortfolio in Craft Education at the Primary Level

    Science.gov (United States)

    Saarinen, Auli; Seitamaa-Hakkarainen, Pirita; Hakkarainen, Kai

    2016-01-01

    The authors investigated primary school pupils' experiences using an electronic portfolio in their craft education for a three year period, from the 3rd grade until the end of the 5th grade. This article emphasizes the functions and the benefits of the ePortfolio method and outlines general user experiences based on pupil interviews (N = 38),…

  2. Developing Community Reinforcement and Family Training (CRAFT) for Parents of Treatment-Resistant Adolescents

    Science.gov (United States)

    Kirby, Kimberly C.; Versek, Brian; Kerwin, MaryLouise E.; Meyers, Kathleen; Benishek, Lois A.; Bresani, Elena; Washio, Yukiko; Arria, Amelia; Meyers, Robert J.

    2015-01-01

    We describe a project focused on training parents to facilitate their treatment-resistant adolescent's treatment entry and to manage their child after entry into community-based treatment. Controlled studies show that Community Reinforcement and Family Training (CRAFT) is a unilateral treatment that fosters treatment entry of adults; however,…

  3. The Teachers' Views on the Significance of the Design and Craft Teaching in Finland

    Science.gov (United States)

    Ronkko, Marja-Leena; Mommo, Sanna; Aerila, Juli-Anna

    2016-01-01

    The Finnish curriculum for crafts emphasises the creative problem-solving skills of the student, the completion of different design tasks and the implementation of designs, while seeking to nurture the student's self-esteem. Furthermore, students should draw up the designs for their artefacts, plan their work, and also develop designs when needed.…

  4. Effects of spent craft brewers’ yeast on fermentation and methane production by rumen microorganisms

    Science.gov (United States)

    Saccharomyces cerevisiae is a key component of beer brewing and a major by-product. The leftover, spent brewers’ yeast, from large breweries has been used for some time as a protein supplement in cattle, however the possible advantages of spent yeast from smaller craft breweries, containing much hig...

  5. Investigation of crafting polymerization of acrylic acid to cellulose materials under the action of accelerated electrons

    International Nuclear Information System (INIS)

    Valiev, A.; Bazhenov, L.G.; Asamov, M.K.; Sagatov, Eh.A.

    1996-01-01

    Crafting polymerization of acrylic acid (AA) to cellulose materials in the presence of copper, zinc and silver salts under the action of accelerated electrons has been investigated with the aim to attach anti microbe properties to these materials. (author). 2 refs., 1 tab

  6. Degradation of spent craft brewer’s yeast by caprine rumen hyper ammonia-producing bacteria

    Science.gov (United States)

    Spent brewer’s yeast has long been included in ruminant diets as a protein supplement. However, modern craft beers often include more hops (Humulus lupulus L.) compounds than traditional recipes. These compounds include alpha and beta-acids, which are antimicrobial to the rumen hyper ammonia-produci...

  7. Friedel-Crafts Alkylation Using Elemental Aluminum Catalyst: An Undergraduate Laboratory Experiment.

    Science.gov (United States)

    Meeks, B. Spencer; Lucas, Anita R.

    1989-01-01

    Provides methodology for carrying out the synthesis of sec-butyltoluene by the Friedel-Crafts alkylation of toluene. Suggests using simple elemental aluminum as the catalyst in place of AlCl3 or amalgamated aluminum. Notes satisfactory results for both macro- and microscale operations. (MVL)

  8. ePerformance: Crafting, Rehearsing, and Presenting the ePortfolio Persona

    Science.gov (United States)

    Ramírez, Kimberly

    2011-01-01

    "ePerformance: Crafting, Rehearsing, and Presenting the ePortfolio Persona" exposes vital intersections between pedagogy and performance to reveal how using ePortfolio encourages not only student-centered learning, but facilitates collaboration through cooperative exchanges. Productive interactivity with audiences who actively influence…

  9. New technologies for fire suppression on board naval craft, FiST

    NARCIS (Netherlands)

    Rahm, M.; Hiltz, J.; Wal, R. van der; Hertzberg, T.; Lindström, J.

    2014-01-01

    For three years Canada, Sweden and the Netherlands have been investigating new technologies for fire suppression on board naval crafts within the FiST project. The project has focused on a number of technologies. These included the evaluation of water based fire suppression systems and in particular

  10. Critical Success Factors in Crafting Strategic Architecture for E-Learning at HP University

    Science.gov (United States)

    Sharma, Kunal; Pandit, Pallvi; Pandit, Parul

    2011-01-01

    Purpose: The purpose of this paper is to outline the critical success factors for crafting a strategic architecture for e-learning at HP University. Design/methodology/approach: A descriptive survey type of research design was used. An empirical study was conducted on students enrolled with the International Centre for Distance and Open Learning…

  11. Proactive personality and job performance: the role of job crafting and work engagement

    NARCIS (Netherlands)

    Bakker, A.B.; Tims, M.; Derks, D.

    2012-01-01

    The article examines the role of proactive personality in predicting work engagement and job performance. On the basis of the literature on proactive personality and the job demands-resources model, we hypothesized that employees with a proactive personality would be most likely to craft their own

  12. Pi-activated alcohols: an emerging class of alkylating agents for catalytic Friedel-Crafts reactions.

    Science.gov (United States)

    Bandini, Marco; Tragni, Michele

    2009-04-21

    The direct functionalization of aromatic compounds, via Friedel-Crafts alkylation reactions with alcohols, is one of the cornerstones in organic chemistry. The present emerging area deals with the recent advances in the use of pi-activated alcohols in the catalytic and stereoselective construction of benzylic stereocenters.

  13. Materials on Creative Arts (Arts, Crafts, Dance, Drama, Music, Bibliotherapy) for Persons with Handicapping Conditions. Revised.

    Science.gov (United States)

    American Alliance for Health, Physical Education, and Recreation, Washington, DC. Information and Research Utilization Center.

    Intended as a resource guide for persons who include such subjects as arts, crafts, dance, and music in programs for the handicapped, resources are listed for printed materials, audiovisual materials, resource persons and organizations, and material and equipment suppliers. Brief literature reviews sum up the state of the art in the specific art…

  14. Job crafting in changing organizations: Antecedents and implications for exhaustion and performance.

    Science.gov (United States)

    Petrou, Paraskevas; Demerouti, Evangelia; Schaufeli, Wilmar B

    2015-10-01

    The present study addressed employee job crafting behaviors (i.e., seeking resources, seeking challenges, and reducing demands) in the context of organizational change. We examined predictors of job crafting both at the organizational level (i.e., perceived impact of the implemented changes on the working life of employees) and the individual level (i.e., employee willingness to follow the changes). Job crafting behaviors were expected to predict task performance and exhaustion. Two-wave longitudinal data from 580 police officers undergoing organizational changes were analyzed with structural equation modeling. Findings showed that the degree to which changes influence employees' daily work was linked to reducing demands and exhaustion, whereas employee willingness to change was linked to seeking resources and seeking challenges. Furthermore, while seeking resources and seeking challenges were associated with high task performance and low exhaustion respectively, reducing demands seemed to predict exhaustion positively. Our findings suggest that job crafting can act as a strategy of employees to respond to organizational change. While seeking resources and seeking challenges enhance employee adjustment and should be encouraged by managers, reducing demands seems to have unfavorable implications for employees. (c) 2015 APA, all rights reserved).

  15. An Empirical Study of the Process of Crafting and Using Definitions

    Science.gov (United States)

    Little, Angela Jean

    2013-01-01

    In this dissertation I analyze the process of crafting definitions whose purpose is classification. The context I examine is undergraduate upper-division physical science majors defining and naming sub-categories of a physical phenomenon in the context of a design task over an extended period of time. The goal of the design task is one of…

  16. 3D DIGITAL SIMULATION OF MINNAN TEMPLE ARCHITECTURE CAISSON'S CRAFT TECHNIQUES

    Directory of Open Access Journals (Sweden)

    Y. C. Lin

    2013-07-01

    Full Text Available Caisson is one of the important representations of the Minnan (southern Fujian temple architecture craft techniques and decorative aesthetics. The special component design and group building method present the architectural thinking and personal characteristics of great carpenters of Minnan temple architecture. In late Qing Dynasty, the appearance and style of caissons of famous temples in Taiwan apparently presented the building techniques of the great carpenters. However, as the years went by, the caisson design and craft techniques were not fully inherited, which has been a great loss of cultural assets. Accordingly, with the caisson of Fulong temple, a work by the well-known great carpenter in Tainan as an example, this study obtained the thinking principles of the original design and the design method at initial period of construction through interview records and the step of redrawing the "Tng-Ko" (traditional design, stakeout and construction tool. We obtained the 3D point cloud model of the caisson of Fulong temple using 3D laser scanning technology, and established the 3D digital model of each component of the caisson. Based on the caisson component procedure obtained from interview records, this study conducted the digital simulation of the caisson component to completely recode and present the caisson design, construction and completion procedure. This model of preserving the craft techniques for Minnan temple caisson by using digital technology makes specific contribution to the heritage of the craft techniques while providing an important reference for the digital preservation of human cultural assets.

  17. Emotions in Risk Assessment and Decision Making Processes During Craft Practice

    Directory of Open Access Journals (Sweden)

    Camilla Groth

    2015-12-01

    Full Text Available Traditionally subjective experiences and emotions have been overlooked in the practice of scientific research. In the field of design and craft research too, feelings and emotions have been considered as interfering with the rigour of research. However, as a result of findings in neuroscience, a new understanding has emerged, providing emotions a central role in risk assessment and decision making processes. This has implications also for how we understand craft practice. In this practice-led research, a craft practitioner analysed five video-recordings of herself while throwing clay blindfolded. The researcher-practitioner specifically studied critical incidents in the throwing process and made a detailed analysis of how sensory experiences and emotions guided her in risk assessment, decision making, and problem solving during the clay-throwing sessions. She found that her tactile experience gave her important clues on the condition of the material and its consequent possibilities at different stages. These experiences in turn affected her emotions in either positive or negative ways, affecting her risk assessment, decision making, and problem solving activities. This research has shown that sensory experiences and emotions influence the craft making process and are thus important elements in the expertise of the craftsperson. The role of such emotions remains to be studied further in the expertise of researchers in general.

  18. Native American Arts and Crafts of the United States. Bibliography 1.

    Science.gov (United States)

    Indian Arts and Crafts Board, Washington, DC.

    The selected readings listed in this annotated bibliography are suggested as an introduction to the varied arts and crafts created from prehistoric to modern times by Native American peoples of the United States. The publications are organized by culture area to encompass major media practiced by Native American artists and craftsmen of these…

  19. Job crafting and extra-role behavior : the role of work engagement and flourishing

    NARCIS (Netherlands)

    Demerouti, E.; Bakker, A.B.; Gevers, J.M.P.

    2015-01-01

    This study investigates whether crafting of job demands and resources relates positively to extra-role behavior (i.e. contextual performance and creativity) through work engagement and flourishing. We collected data from 294 employees and their supervisors regarding employees' contextual performance

  20. A Resource Guide on Indian Arts and Crafts for Elementary and Secondary Teachers.

    Science.gov (United States)

    Fagot, Madeleine

    American Indian arts and crafts reference materials (published 1923-1973) are listed in this annotated resource guide for elementary and secondary school teachers. Approximately 260 listings are given for: books, films and filmstrips, maps and charts, picture sets, magazines, bibliographies and indexes, slide kits, transparencies, distributor's…