Science.gov

Sample records for 40-bit floating point

  1. The application of the ADSP-21020 40-bit floating point DSP microprocessor in a digital Doppler radar

    SciTech Connect

    Robinson, S.H.; Morrison, R.E.

    1991-08-26

    A continuous wave doppler radar system has been designed which is portable, easily deployable and can be remotely controlled. The system is immune to ground clutter and is used for wind speed detection and direction determination. Nearly real time digital signal processing is performed by an Analog Devices ADSP-21020, a 40-bit floating point Digital Signal Processing (DSP) microprocessor. This paper provides an overview of the design of the system including the radio frequency (RF) to digital interface. The various DSP detection algorithms are discussed and compared to system performance and sensitivity. Finally, DSP performance is compared to the performance of an earlier system using Analog Device's ADSP-2100. 6 refs.

  2. Hardware description ADSP-21020 40-bit floating point DSP as designed in a remotely controlled digital CW Doppler radar

    SciTech Connect

    Morrison, R.E.; Robinson, S.H.

    1991-01-01

    A continuous wave Doppler radar system has been designed which is portable, easily deployed, and remotely controlled. The heart of this system is a DSP/control board using Analog Devices ADSP-21020 40-bit floating point digital signal processor (DSP) microprocessor. Two 18-bit audio A/D converters provide digital input to the DSP/controller board for near real time target detection. Program memory for the DSP is dual ported with an Intel 87C51 microcontroller allowing DSP code to be up-loaded or down-loaded from a central controlling computer. The 87C51 provides overall system control for the remote radar and includes a time-of-day/day-of-year real time clock, system identification (ID) switches, and input/output (I/O) expansion by an Intel 82C55 I/O expander. 5 refs., 8 figs., 2 tabs.

  3. Floating Point Control Library

    Energy Science and Technology Software Center (ESTSC)

    2007-08-02

    Floating Point Control is a Library that allows for the manipulation of floating point unit exception masking funtions control exceptions in both the Streaming "Single Instruction, Multiple Data" Extension 2 (SSE2) unit and the floating point unit simultaneously. FPC also provides macros to set floating point rounding and precision control.

  4. NULL convention floating point multiplier.

    PubMed

    Albert, Anitha Juliette; Ramachandran, Seshasayanan

    2015-01-01

    Floating point multiplication is a critical part in high dynamic range and computational intensive digital signal processing applications which require high precision and low power. This paper presents the design of an IEEE 754 single precision floating point multiplier using asynchronous NULL convention logic paradigm. Rounding has not been implemented to suit high precision applications. The novelty of the research is that it is the first ever NULL convention logic multiplier, designed to perform floating point multiplication. The proposed multiplier offers substantial decrease in power consumption when compared with its synchronous version. Performance attributes of the NULL convention logic floating point multiplier, obtained from Xilinx simulation and Cadence, are compared with its equivalent synchronous implementation. PMID:25879069

  5. NULL Convention Floating Point Multiplier

    PubMed Central

    Ramachandran, Seshasayanan

    2015-01-01

    Floating point multiplication is a critical part in high dynamic range and computational intensive digital signal processing applications which require high precision and low power. This paper presents the design of an IEEE 754 single precision floating point multiplier using asynchronous NULL convention logic paradigm. Rounding has not been implemented to suit high precision applications. The novelty of the research is that it is the first ever NULL convention logic multiplier, designed to perform floating point multiplication. The proposed multiplier offers substantial decrease in power consumption when compared with its synchronous version. Performance attributes of the NULL convention logic floating point multiplier, obtained from Xilinx simulation and Cadence, are compared with its equivalent synchronous implementation. PMID:25879069

  6. Program Converts VAX Floating-Point Data To UNIX

    NASA Technical Reports Server (NTRS)

    Alves, Marcos; Chapman, Bruce; Chu, Eugene

    1996-01-01

    VAX Floating Point to Host Floating Point Conversion (VAXFC) software converts non-ASCII files to unformatted floating-point representation of UNIX machine. This is done by reading bytes bit by bit, converting them to floating-point numbers, then writing results to another file. Useful when data files created by VAX computer must be used on other machines. Written in C language.

  7. Improvements in floating point addition/subtraction operations

    DOEpatents

    Farmwald, P.M.

    1984-02-24

    Apparatus is described for decreasing the latency time associated with floating point addition and subtraction in a computer, using a novel bifurcated, pre-normalization/post-normalization approach that distinguishes between differences of floating point exponents.

  8. An integrated circuit floating point accumulator

    NASA Technical Reports Server (NTRS)

    Goldsmith, T. C.

    1977-01-01

    Goddard Space Flight Center has developed a large scale integrated circuit (type 623) which can perform pulse counting, storage, floating point compression, and serial transmission, using a single monolithic device. Counts of 27 or 19 bits can be converted to transmitted values of 12 or 8 bits respectively. Use of the 623 has resulted in substantial savaings in weight, volume, and dollar resources on at least 11 scientific instruments to be flown on 4 NASA spacecraft. The design, construction, and application of the 623 are described.

  9. Defining the IEEE-854 floating-point standard in PVS

    NASA Technical Reports Server (NTRS)

    Miner, Paul S.

    1995-01-01

    A significant portion of the ANSI/IEEE-854 Standard for Radix-Independent Floating-Point Arithmetic is defined in PVS (Prototype Verification System). Since IEEE-854 is a generalization of the ANSI/IEEE-754 Standard for Binary Floating-Point Arithmetic, the definition of IEEE-854 in PVS also formally defines much of IEEE-754. This collection of PVS theories provides a basis for machine checked verification of floating-point systems. This formal definition illustrates that formal specification techniques are sufficiently advanced that is is reasonable to consider their use in the development of future standards.

  10. Open source high performance floating-point modules.

    SciTech Connect

    Underwood, Keith Douglas

    2006-02-01

    Given the logic density of modern FPGAs, it is feasible to use FPGAs for floating-point applications. However, it is important that any floating-point units that are used be highly optimized. This paper introduces an open source library of highly optimized floating-point units for Xilinx FPGAs. The units are fully IEEE compliant and achieve approximately 230 MHz operation frequency for double-precision add and multiply in a Xilinx Virtex-2-Pro FPGA (-7 speed grade). This speed is achieved with a 10 stage adder pipeline and a 12 stage multiplier pipeline. The area requirement is 571 slices for the adder and 905 slices for the multiplier.

  11. Design of a reversible single precision floating point subtractor.

    PubMed

    Anantha Lakshmi, Av; Sudha, Gf

    2014-01-01

    In recent years, Reversible logic has emerged as a major area of research due to its ability to reduce the power dissipation which is the main requirement in the low power digital circuit design. It has wide applications like low power CMOS design, Nano-technology, Digital signal processing, Communication, DNA computing and Optical computing. Floating-point operations are needed very frequently in nearly all computing disciplines, and studies have shown floating-point addition/subtraction to be the most used floating-point operation. However, few designs exist on efficient reversible BCD subtractors but no work on reversible floating point subtractor. In this paper, it is proposed to present an efficient reversible single precision floating-point subtractor. The proposed design requires reversible designs of an 8-bit and a 24-bit comparator unit, an 8-bit and a 24-bit subtractor, and a normalization unit. For normalization, a 24-bit Reversible Leading Zero Detector and a 24-bit reversible shift register is implemented to shift the mantissas. To realize a reversible 1-bit comparator, in this paper, two new 3x3 reversible gates are proposed The proposed reversible 1-bit comparator is better and optimized in terms of the number of reversible gates used, the number of transistor count and the number of garbage outputs. The proposed work is analysed in terms of number of reversible gates, garbage outputs, constant inputs and quantum costs. Using these modules, an efficient design of a reversible single precision floating point subtractor is proposed. Proposed circuits have been simulated using Modelsim and synthesized using Xilinx Virtex5vlx30tff665-3. The total on-chip power consumed by the proposed 32-bit reversible floating point subtractor is 0.410 W. PMID:24455466

  12. The Unified Floating Point Vector Coprocessor for Reconfigurable Hardware

    NASA Astrophysics Data System (ADS)

    Kathiara, Jainik

    There has been an increased interest recently in using embedded cores on FPGAs. Many of the applications that make use of these cores have floating point operations. Due to the complexity and expense of floating point hardware, these algorithms are usually converted to fixed point operations or implemented using floating-point emulation in software. As the technology advances, more and more homogeneous computational resources and fixed function embedded blocks are added to FPGAs and hence implementation of floating point hardware becomes a feasible option. In this research we have implemented a high performance, autonomous floating point vector Coprocessor (FPVC) that works independently within an embedded processor system. We have presented a unified approach to vector and scalar computation, using a single register file for both scalar operands and vector elements. The Hybrid vector/SIMD computational model of FPVC results in greater overall performance for most applications along with improved peak performance compared to other approaches. By parameterizing vector length and the number of vector lanes, we can design an application specific FPVC and take optimal advantage of the FPGA fabric. For this research we have also initiated designing a software library for various computational kernels, each of which adapts FPVC's configuration and provide maximal performance. The kernels implemented are from the area of linear algebra and include matrix multiplication and QR and Cholesky decomposition. We have demonstrated the operation of FPVC on a Xilinx Virtex 5 using the embedded PowerPC.

  13. Floating-to-Fixed-Point Conversion for Digital Signal Processors

    NASA Astrophysics Data System (ADS)

    Menard, Daniel; Chillet, Daniel; Sentieys, Olivier

    2006-12-01

    Digital signal processing applications are specified with floating-point data types but they are usually implemented in embedded systems with fixed-point arithmetic to minimise cost and power consumption. Thus, methodologies which establish automatically the fixed-point specification are required to reduce the application time-to-market. In this paper, a new methodology for the floating-to-fixed point conversion is proposed for software implementations. The aim of our approach is to determine the fixed-point specification which minimises the code execution time for a given accuracy constraint. Compared to previous methodologies, our approach takes into account the DSP architecture to optimise the fixed-point formats and the floating-to-fixed-point conversion process is coupled with the code generation process. The fixed-point data types and the position of the scaling operations are optimised to reduce the code execution time. To evaluate the fixed-point computation accuracy, an analytical approach is used to reduce the optimisation time compared to the existing methods based on simulation. The methodology stages are described and several experiment results are presented to underline the efficiency of this approach.

  14. Fast and efficient compression of floating-point data.

    PubMed

    Lindstrom, Peter; Isenburg, Martin

    2006-01-01

    Large scale scientific simulation codes typically run on a cluster of CPUs that write/read time steps to/from a single file system. As data sets are constantly growing in size, this increasingly leads to I/O bottlenecks. When the rate at which data is produced exceeds the available I/O bandwidth, the simulation stalls and the CPUs are idle. Data compression can alleviate this problem by using some CPU cycles to reduce the amount of data needed to be transfered. Most compression schemes, however, are designed to operate offline and seek to maximize compression, not throughput. Furthermore, they often require quantizing floating-point values onto a uniform integer grid, which disqualifies their use in applications where exact values must be retained. We propose a simple scheme for lossless, online compression of floating-point data that transparently integrates into the I/O of many applications. A plug-in scheme for data-dependent prediction makes our scheme applicable to a wide variety of data used in visualization, such as unstructured meshes, point sets, images, and voxel grids. We achieve state-of-the-art compression rates and speeds, the latter in part due to an improved entropy coder. We demonstrate that this significantly accelerates I/O throughput in real simulation runs. Unlike previous schemes, our method also adapts well to variable-precision floating-point and integer data. PMID:17080858

  15. Bifurcated method and apparatus for floating point addition with decreased latency time

    DOEpatents

    Farmwald, Paul M.

    1987-01-01

    Apparatus for decreasing the latency time associated with floating point addition and subtraction in a computer, using a novel bifurcated, pre-normalization/post-normalization approach that distinguishes between differences of floating point exponents.

  16. CMOS floating-point vector-arithmetic unit

    NASA Astrophysics Data System (ADS)

    Timmermann, D.; Rix, B.; Hahn, H.; Hosticka, B. J.

    1994-05-01

    This work describes a floating-point arithmetic unit based on the CORDIC algorithm. The unit computes a full set of high level arithmetic and elementary functions: multiplication, division, (co)sine, hyperbolic (co)sine, square root, natural logarithm, inverse (hyperbolic) tangent, vector norm, and phase. The chip has been integrated in 1.6 micron double-metal n-well CMOS technology and achieves a normalized peak performance of 220 MFLOPS.

  17. Multi-input and binary reproducible, high bandwidth floating point adder in a collective network

    DOEpatents

    Chen, Dong; Eisley, Noel A; Heidelberger, Philip; Steinmacher-Burow, Burkhard

    2015-03-10

    To add floating point numbers in a parallel computing system, a collective logic device receives the floating point numbers from computing nodes. The collective logic devices converts the floating point numbers to integer numbers. The collective logic device adds the integer numbers and generating a summation of the integer numbers. The collective logic device converts the summation to a floating point number. The collective logic device performs the receiving, the converting the floating point numbers, the adding, the generating and the converting the summation in one pass. One pass indicates that the computing nodes send inputs only once to the collective logic device and receive outputs only once from the collective logic device.

  18. Fixed-Rate Compressed Floating-Point Arrays.

    PubMed

    Lindstrom, Peter

    2014-12-01

    Current compression schemes for floating-point data commonly take fixed-precision values and compress them to a variable-length bit stream, complicating memory management and random access. We present a fixed-rate, near-lossless compression scheme that maps small blocks of 4(d) values in d dimensions to a fixed, user-specified number of bits per block, thereby allowing read and write random access to compressed floating-point data at block granularity. Our approach is inspired by fixed-rate texture compression methods widely adopted in graphics hardware, but has been tailored to the high dynamic range and precision demands of scientific applications. Our compressor is based on a new, lifted, orthogonal block transform and embedded coding, allowing each per-block bit stream to be truncated at any point if desired, thus facilitating bit rate selection using a single compression scheme. To avoid compression or decompression upon every data access, we employ a software write-back cache of uncompressed blocks. Our compressor has been designed with computational simplicity and speed in mind to allow for the possibility of a hardware implementation, and uses only a small number of fixed-point arithmetic operations per compressed value. We demonstrate the viability and benefits of lossy compression in several applications, including visualization, quantitative data analysis, and numerical simulation. PMID:26356981

  19. Floating-point function generation routines for 16-bit microcomputers

    NASA Technical Reports Server (NTRS)

    Mackin, M. A.; Soeder, J. F.

    1984-01-01

    Several computer subroutines have been developed that interpolate three types of nonanalytic functions: univariate, bivariate, and map. The routines use data in floating-point form. However, because they are written for use on a 16-bit Intel 8086 system with an 8087 mathematical coprocessor, they execute as fast as routines using data in scaled integer form. Although all of the routines are written in assembly language, they have been implemented in a modular fashion so as to facilitate their use with high-level languages.

  20. Double-Precision Floating-Point Cores V1.9

    Energy Science and Technology Software Center (ESTSC)

    2005-10-15

    In studying the acceleration of scientific computing applications with reconfigurable hardware, such as field programmable gate arrays, one finds that many scientific applications require high-precision, floating-point arithmetic that is not innately supported in reconfigurable hardware. Consequently, we have written VDL code that describes hardware for performing double-precision (64-bit) floating-point arithmetic. From this code, it is possible for users to implement double-precision floating-point operations on FPGAs or any other hardware device to which VHDL code canmore » be synthesized. Specifically, we have written code for four floating-point cores. Each core performs one operation: one performs addition/subtraction, one performs multiplication, one performs division, and one performs square root. The code includes parameters that determine the features of the floating-point cores, such as what types of floating-point numbers are supported and what roudning modes are supported. These parameters influence the frequency achievable by the designs as well as the chip area required for the designs. The parameters are chosen so that the floating-point cores have varyinig amounts of compliance with the industry standard for floating-point cores have varying amounts of compliance with the industry standard for floating-point arithmetic, IEEE standard 754. There is an additional parameter that determines the number of pipelining stages in the floating-point cores.« less

  1. Double-Precision Floating-Point Cores V1.9

    SciTech Connect

    Govindu, Gokul; Scrofano, Ronald

    2005-10-15

    In studying the acceleration of scientific computing applications with reconfigurable hardware, such as field programmable gate arrays, one finds that many scientific applications require high-precision, floating-point arithmetic that is not innately supported in reconfigurable hardware. Consequently, we have written VDL code that describes hardware for performing double-precision (64-bit) floating-point arithmetic. From this code, it is possible for users to implement double-precision floating-point operations on FPGAs or any other hardware device to which VHDL code can be synthesized. Specifically, we have written code for four floating-point cores. Each core performs one operation: one performs addition/subtraction, one performs multiplication, one performs division, and one performs square root. The code includes parameters that determine the features of the floating-point cores, such as what types of floating-point numbers are supported and what roudning modes are supported. These parameters influence the frequency achievable by the designs as well as the chip area required for the designs. The parameters are chosen so that the floating-point cores have varyinig amounts of compliance with the industry standard for floating-point cores have varying amounts of compliance with the industry standard for floating-point arithmetic, IEEE standard 754. There is an additional parameter that determines the number of pipelining stages in the floating-point cores.

  2. Fixed-rate compressed floating-point arrays

    Energy Science and Technology Software Center (ESTSC)

    2014-03-30

    ZFP is a library for lossy compression of single- and double-precision floating-point data. One of the unique features of ZFP is its support for fixed-rate compression, which enables random read and write access at the granularity of small blocks of values. Using a C++ interface, this allows declaring compressed arrays (1D, 2D, and 3D arrays are supported) that through operator overloading can be treated just like conventional, uncompressed arrays, but which allow the user tomore » specify the exact number of bits to allocate to the array. ZFP also has variable-rate fixed-precision and fixed-accuracy modes, which allow the user to specify a tolerance on the relative or absolute error.« less

  3. Floating point fault tolerance with backward error assertions

    SciTech Connect

    Boley, D.; Golub, G.H.; Makar, S.; Saxena, N.; Mccluskey, E.J.

    1995-02-01

    This paper introduces an assertion scheme based on the backward error analysis for error detection in algorithms that solve dense systems of linear equations, Ax = b. Unlike previous methods, this Backward Error Assertion Model is specifically designed to operate in an environment of floating point arithmetic subject to round-off errors, and it can be easily instrumented in a Watchdog processor environment. The complexity of verifying assertions is Omicron (n(sup 2)), compared to the Omicron (n(sup 3)) complexity of algorithms solving Ax = b. Unlike other proposed error detection methods, this assertion model does not require any encoding of the matrix A. Experimental results under various error models are presented to validate the effectiveness of this assertion scheme. 22 refs.

  4. Error bounds on complex floating-point multiplication

    NASA Astrophysics Data System (ADS)

    Brent, Richard; Percival, Colin; Zimmermann, Paul

    2007-09-01

    Given floating-point arithmetic with t -digit base- beta significands in which all arithmetic operations are performed as if calculated to infinite precision and rounded to a nearest representable value, we prove that the product of complex values z_0 and z_1 can be computed with maximum absolute error \\vert z_0Vert z_1\\vert frac{1}{2} beta^{1 - t} sqrt{5} . In particular, this provides relative error bounds of 2^{-24} sqrt{5} and 2^{-53} sqrt{5} for IEEE 754 single and double precision arithmetic respectively, provided that overflow, underflow, and denormals do not occur. We also provide the numerical worst cases for IEEE 754 single and double precision arithmetic.

  5. Floating point only SIMD instruction set architecture including compare, select, Boolean, and alignment operations

    DOEpatents

    Gschwind, Michael K.

    2011-03-01

    Mechanisms for implementing a floating point only single instruction multiple data instruction set architecture are provided. A processor is provided that comprises an issue unit, an execution unit coupled to the issue unit, and a vector register file coupled to the execution unit. The execution unit has logic that implements a floating point (FP) only single instruction multiple data (SIMD) instruction set architecture (ISA). The floating point vector registers of the vector register file store both scalar and floating point values as vectors having a plurality of vector elements. The processor may be part of a data processing system.

  6. The complexity of class polynomial computation via floating point approximations

    NASA Astrophysics Data System (ADS)

    Enge, Andreas

    2009-06-01

    We analyse the complexity of computing class polynomials, that are an important ingredient for CM constructions of elliptic curves, via complex floating point approximations of their roots. The heart of the algorithm is the evaluation of modular functions in several arguments. The fastest one of the presented approaches uses a technique devised by Dupont to evaluate modular functions by Newton iterations on an expression involving the arithmetic-geometric mean. Under the heuristic assumption, justified by experiments, that the correctness of the result is not perturbed by rounding errors, the algorithm runs in time O left( sqrt {\\vert D\\vert} log^3 \\vert D\\vert M left( sq... ...arepsilon} \\vert D\\vert right) subseteq O left( h^{2 + \\varepsilon} right) for any \\varepsilon > 0 , where D is the CM discriminant, h is the degree of the class polynomial and M (n) is the time needed to multiply two n -bit numbers. Up to logarithmic factors, this running time matches the size of the constructed polynomials. The estimate also relies on a new result concerning the complexity of enumerating the class group of an imaginary quadratic order and on a rigorously proven upper bound for the height of class polynomials.

  7. Floating-point performance of ARM cores and their efficiency in classical molecular dynamics

    NASA Astrophysics Data System (ADS)

    Nikolskiy, V.; Stegailov, V.

    2016-02-01

    Supercomputing of the exascale era is going to be inevitably limited by power efficiency. Nowadays different possible variants of CPU architectures are considered. Recently the development of ARM processors has come to the point when their floating point performance can be seriously considered for a range of scientific applications. In this work we present the analysis of the floating point performance of the latest ARM cores and their efficiency for the algorithms of classical molecular dynamics.

  8. Floating point software package for use on LSI-11 computers at SLAC

    SciTech Connect

    Hendra, R.G.

    1981-06-01

    A floating point software package has been devised to allow full use of the floating point hardware of the LSI-11 and MODEL40 computers. The procedures are written for the most part in the PL-11 language. The package may be run under the RT-11 operating system, or in RAM or EPROM as part of the KERNEL package. The current set of procedures has been run successfully in all three modes.

  9. Generating and executing programs for a floating point single instruction multiple data instruction set architecture

    DOEpatents

    Gschwind, Michael K

    2013-04-16

    Mechanisms for generating and executing programs for a floating point (FP) only single instruction multiple data (SIMD) instruction set architecture (ISA) are provided. A computer program product comprising a computer recordable medium having a computer readable program recorded thereon is provided. The computer readable program, when executed on a computing device, causes the computing device to receive one or more instructions and execute the one or more instructions using logic in an execution unit of the computing device. The logic implements a floating point (FP) only single instruction multiple data (SIMD) instruction set architecture (ISA), based on data stored in a vector register file of the computing device. The vector register file is configured to store both scalar and floating point values as vectors having a plurality of vector elements.

  10. Performance of FORTRAN floating-point operations on the Flex/32 multicomputer

    NASA Technical Reports Server (NTRS)

    Crockett, Thomas W.

    1987-01-01

    A series of experiments has been run to examine the floating-point performance of FORTRAN programs on the Flex/32 (Trademark) computer. The experiments are described, and the timing results are presented. The time required to execute a floating-point operation is found to vary considerbaly depending on a number of factors. One factor of particular interest from an algorithm design standpoint is the difference in speed between common memory accesses and local memory accesses. Common memory accesses were found to be slower, and guidelines are given for determinig when it may be cost effective to copy data from common to local memory.

  11. A High-Level Formalization of Floating-Point Number in PVS

    NASA Technical Reports Server (NTRS)

    Boldo, Sylvie; Munoz, Cesar

    2006-01-01

    We develop a formalization of floating-point numbers in PVS based on a well-known formalization in Coq. We first describe the definitions of all the needed notions, e.g., floating-point number, format, rounding modes, etc.; then, we present an application to polynomial evaluation for elementary function evaluation. The application already existed in Coq, but our formalization shows a clear improvement in the quality of the result due to the automation provided by PVS. We finally integrate our formalization into a PVS hardware-level formalization of the IEEE-854 standard previously developed at NASA.

  12. Floating-Point Units and Algorithms for field-programmable gate arrays

    Energy Science and Technology Software Center (ESTSC)

    2005-11-01

    The software that we are attempting to copyright is a package of floating-point unit descriptions and example algorithm implementations using those units for use in FPGAs. The floating point units are best-in-class implementations of add, multiply, divide, and square root floating-point operations. The algorithm implementations are sample (not highly flexible) implementations of FFT, matrix multiply, matrix vector multiply, and dot product. Together, one could think of the collection as an implementation of parts of themore » BLAS library or something similar to the FFTW packages (without the flexibility) for FPGAs. Results from this work has been published multiple times and we are working on a publication to discuss the techniques we use to implement the floating-point units, For some more background, FPGAS are programmable hardware. "Programs" for this hardware are typically created using a hardware description language (examples include Verilog, VHDL, and JHDL). Our floating-point unit descriptions are written in JHDL, which allows them to include placement constraints that make them highly optimized relative to some other implementations of floating-point units. Many vendors (Nallatech from the UK, SRC Computers in the US) have similar implementations, but our implementations seem to be somewhat higher performance. Our algorithm implementations are written in VHDL and models of the floating-point units are provided in VHDL as well. FPGA "programs" make multiple "calls" (hardware instantiations) to libraries of intellectual property (IP), such as the floating-point unit library described here. These programs are then compiled using a tool called a synthesizer (such as a tool from Synplicity, Inc.). The compiled file is a netlist of gates and flip-flops. This netlist is then mapped to a particular type of FPGA by a mapper and then a place- and-route tool. These tools assign the gates in the netlist to specific locations on the specific type of FPGA chip used

  13. Floating-Point Units and Algorithms for field-programmable gate arrays

    SciTech Connect

    Underwood, Keith D.; Hemmert, K. Scott

    2005-11-01

    The software that we are attempting to copyright is a package of floating-point unit descriptions and example algorithm implementations using those units for use in FPGAs. The floating point units are best-in-class implementations of add, multiply, divide, and square root floating-point operations. The algorithm implementations are sample (not highly flexible) implementations of FFT, matrix multiply, matrix vector multiply, and dot product. Together, one could think of the collection as an implementation of parts of the BLAS library or something similar to the FFTW packages (without the flexibility) for FPGAs. Results from this work has been published multiple times and we are working on a publication to discuss the techniques we use to implement the floating-point units, For some more background, FPGAS are programmable hardware. "Programs" for this hardware are typically created using a hardware description language (examples include Verilog, VHDL, and JHDL). Our floating-point unit descriptions are written in JHDL, which allows them to include placement constraints that make them highly optimized relative to some other implementations of floating-point units. Many vendors (Nallatech from the UK, SRC Computers in the US) have similar implementations, but our implementations seem to be somewhat higher performance. Our algorithm implementations are written in VHDL and models of the floating-point units are provided in VHDL as well. FPGA "programs" make multiple "calls" (hardware instantiations) to libraries of intellectual property (IP), such as the floating-point unit library described here. These programs are then compiled using a tool called a synthesizer (such as a tool from Synplicity, Inc.). The compiled file is a netlist of gates and flip-flops. This netlist is then mapped to a particular type of FPGA by a mapper and then a place- and-route tool. These tools assign the gates in the netlist to specific locations on the specific type of FPGA chip used and

  14. Software Aspects of IEEE Floating-Point Computations for Numerical Applications in High Energy Physics

    SciTech Connect

    2010-05-11

    Floating-point computations are at the heart of much of the computing done in high energy physics. The correctness, speed and accuracy of these computations are of paramount importance. The lack of any of these characteristics can mean the difference between new, exciting physics and an embarrassing correction. This talk will examine practical aspects of IEEE 754-2008 floating-point arithmetic as encountered in HEP applications. After describing the basic features of IEEE floating-point arithmetic, the presentation will cover: common hardware implementations (SSE, x87) techniques for improving the accuracy of summation, multiplication and data interchange compiler options for gcc and icc affecting floating-point operations hazards to be avoided About the speaker Jeffrey M Arnold is a Senior Software Engineer in the Intel Compiler and Languages group at Intel Corporation. He has been part of the Digital->Compaq->Intel compiler organization for nearly 20 years; part of that time, he worked on both low- and high-level math libraries. Prior to that, he was in the VMS Engineering organization at Digital Equipment Corporation. In the late 1980s, Jeff spent 2½ years at CERN as part of the CERN/Digital Joint Project. In 2008, he returned to CERN to spent 10 weeks working with CERN/openlab. Since that time, he has returned to CERN multiple times to teach at openlab workshops and consult with various LHC experiments. Jeff received his Ph.D. in physics from Case Western Reserve University.

  15. Software Aspects of IEEE Floating-Point Computations for Numerical Applications in High Energy Physics

    ScienceCinema

    None

    2011-10-06

    Floating-point computations are at the heart of much of the computing done in high energy physics. The correctness, speed and accuracy of these computations are of paramount importance. The lack of any of these characteristics can mean the difference between new, exciting physics and an embarrassing correction. This talk will examine practical aspects of IEEE 754-2008 floating-point arithmetic as encountered in HEP applications. After describing the basic features of IEEE floating-point arithmetic, the presentation will cover: common hardware implementations (SSE, x87) techniques for improving the accuracy of summation, multiplication and data interchange compiler options for gcc and icc affecting floating-point operations hazards to be avoided About the speaker Jeffrey M Arnold is a Senior Software Engineer in the Intel Compiler and Languages group at Intel Corporation. He has been part of the Digital->Compaq->Intel compiler organization for nearly 20 years; part of that time, he worked on both low- and high-level math libraries. Prior to that, he was in the VMS Engineering organization at Digital Equipment Corporation. In the late 1980s, Jeff spent 2½ years at CERN as part of the CERN/Digital Joint Project. In 2008, he returned to CERN to spent 10 weeks working with CERN/openlab. Since that time, he has returned to CERN multiple times to teach at openlab workshops and consult with various LHC experiments. Jeff received his Ph.D. in physics from Case Western Reserve University.

  16. RANS Simulation of the Heave Response of a Two-Body Floating Point Wave Absorber: Preprint

    SciTech Connect

    Yu, Y.; Li, Y.

    2011-03-01

    A preliminary study on a two-body floating wave absorbers is presented in this paper. A Reynolds-Averaged Navier-Stokes computational method is applied for analyzing the hydrodynamic heave response of the absorber in operational wave conditions. The two-body floating wave absorber contains a float section and a submerged reaction section. For validation purposes, our model is first assumed to be locked. The two sections are forced to move together with each other. The locked single body model is used in a heave decay test, where the RANS result is validated with the experimental measurement. For the two-body floating point absorber simulation, the two sections are connected through a mass-spring-damper system, which is applied to simulate the power take-off mechanism under design wave conditions. Overall, the details of the flow around the absorber and its nonlinear interaction with waves are investigated, and the power absorption efficiency of the two-body floating wave absorber in waves with a constant value spring-damper system is examined.

  17. A device to improve the SNR of the measurement of the positional floating reference point

    NASA Astrophysics Data System (ADS)

    Jiang, Jingying; Rong, Xuzheng; Zhang, Hao; Xu, Kexin

    2013-02-01

    Previous studies have preliminarily validated the floating reference method and shown that it has the potential to improve the accuracy of non-invasive blood glucose sensing by Near-Infrared Spectroscopy. In order to make this method practical, it is necessary to precisely verify and measure the existence and variation features of the positional floating reference point. In this talk, a device which can precisely verify and measure the positional floating reference point is built. Since the light intensity of diffuse reflectance from the tested sample is very weak, a multipath detecting fibers system was built to improve signal-to-noise ratio. In this system, the fibers encircle the light source fiber which is regarded as the reference center of detecting fibers while they are moving. In addition, the position of each fiber is accurately controlled by manual translation stage to keep all detecting fibers always in the same radius around light source fiber. This ensures that received signal is coming from the same radial distance of light source. The variation of signal-to-noise ratio along with the different radial distance was investigated based on experiments. Results show that the application of this device could improve signal-to-noise ratio, and provide a new experimental method for the further study of positional floating reference point.

  18. An analysis of the double-precision floating-point FFT on FPGAs.

    SciTech Connect

    Hemmert, K. Scott; Underwood, Keith Douglas

    2005-01-01

    Advances in FPGA technology have led to dramatic improvements in double precision floating-point performance. Modern FPGAs boast several GigaFLOPs of raw computing power. Unfortunately, this computing power is distributed across 30 floating-point units with over 10 cycles of latency each. The user must find two orders of magnitude more parallelism than is typically exploited in a single microprocessor; thus, it is not clear that the computational power of FPGAs can be exploited across a wide range of algorithms. This paper explores three implementation alternatives for the fast Fourier transform (FFT) on FPGAs. The algorithms are compared in terms of sustained performance and memory requirements for various FFT sizes and FPGA sizes. The results indicate that FPGAs are competitive with microprocessors in terms of performance and that the 'correct' FFT implementation varies based on the size of the transform and the size of the FPGA.

  19. Interpretation of IEEE-854 floating-point standard and definition in the HOL system

    NASA Technical Reports Server (NTRS)

    Carreno, Victor A.

    1995-01-01

    The ANSI/IEEE Standard 854-1987 for floating-point arithmetic is interpreted by converting the lexical descriptions in the standard into mathematical conditional descriptions organized in tables. The standard is represented in higher-order logic within the framework of the HOL (Higher Order Logic) system. The paper is divided in two parts with the first part the interpretation and the second part the description in HOL.

  20. Constrained Chebyshev approximations to some elementary functions suitable for evaluation with floating point arithmetic

    NASA Technical Reports Server (NTRS)

    Manos, P.; Turner, L. R.

    1972-01-01

    Approximations which can be evaluated with precision using floating-point arithmetic are presented. The particular set of approximations thus far developed are for the function TAN and the functions of USASI FORTRAN excepting SQRT and EXPONENTIATION. These approximations are, furthermore, specialized to particular forms which are especially suited to a computer with a small memory, in that all of the approximations can share one general purpose subroutine for the evaluation of a polynomial in the square of the working argument.

  1. Real-time 2D floating-point fast Fourier transforms for seeker simulation

    NASA Astrophysics Data System (ADS)

    Chamberlain, Richard; Lord, Eric; Shand, David J.

    2002-07-01

    The floating point Fast Fourier Transform (FFT) is one of the most useful basic functions available to the image and signal processing engineer allowing many complex and detailed special functions to be implemented more simply in the frequency domain. In the Hardware-in-the-Loop field an image transformed using FFT would allow the designer to think about accurate frequency based simulation of seeker lens effects, motion blur, detector transfer functions and much more. Unfortunately, the transform requires many hundreds of thousands or millions of floating point operations on a single modest sized image making it impractical for realtime Hardware-in-the-Loop systems. .until now. This paper outlines the development, by Nallatech, of an FPGA based IEEE floating point core. It traces the subsequent use of this core to develop a full 256 X 256 FFT and filter process implemented on COTS hardware at frame rates up to 150Hz. This transform can be demonstrated to model optical transfer functions at a far greater accuracy than the current spatial models. Other applications and extensions of this technique will be discussed such as filtering for image tracking algorithms and in the simulation of radar processing in the frequency domain.

  2. Experimental Investigation of the Power Generation Performance of Floating-Point Absorber Wave Energy Systems: Preprint

    SciTech Connect

    Li, Y.; Yu, Y.; Epler, J.; Previsic, M.

    2012-04-01

    The extraction of energy from ocean waves has gained interest in recent years. The floating-point absorber (FPA) is one of the most promising devices among a wide variety of wave energy conversion technologies. Early theoretical studies mainly focused on understanding the hydrodynamics of the system and on predicting the maximum power that could be extracted by a heaving body. These studies evolve from the investigation of floating-body interactions in offshore engineering and naval architecture disciplines. To our best knowledge, no systematic study has been reported about the investigation of the power generation performance of an FPA with a close-to-commercial design. A series of experimental tests was conducted to investigate the power extraction performance of an FPA system.

  3. Evaluation of floating-point sum or difference of products in carry-save domain

    NASA Technical Reports Server (NTRS)

    Wahab, A.; Erdogan, S.; Premkumar, A. B.

    1992-01-01

    An architecture to evaluate a 24-bit floating-point sum or difference of products using modified sequential carry-save multipliers with extensive pipelining is described. The basic building block of the architecture is a carry-save multiplier with built-in mantissa alignment for the summation during the multiplication cycles. A carry-save adder, capable of mantissa alignment, correctly positions products with the current carry-save sum. Carry propagation in individual multipliers is avoided and is only required once to produce the final result.

  4. Application of a floating point systems AP190L array processor to finite element analysis

    SciTech Connect

    Young, R.C.

    1982-04-01

    This report discusses the implementation of a finite element program on a Floating Point Systems AP190L array processor attached to a Univac 1182 host computer. The array processor was used to perform all calculations on the global system of linear equations including matrix assembly, matrix factoring and vector solution. A large scratch disk was attached directly to the array processor for storing the factored matrix. The remaining calculations, including data preparation, element matrix formation, stress integration and output display were performed by the host computer.

  5. Lithium-ion drifting: Application to the study of point defects in floating-zone silicon

    NASA Technical Reports Server (NTRS)

    Walton, J. T.; Wong, Y. K.; Zulehner, W.

    1997-01-01

    The use of lithium-ion (Li(+)) drifting to study the properties of point defects in p-type Floating-Zone (FZ) silicon crystals is reported. The Li(+) drift technique is used to detect the presence of vacancy-related defects (D defects) in certain p-type FZ silicon crystals. SUPREM-IV modeling suggests that the silicon point defect diffusivities are considerably higher than those commonly accepted, but are in reasonable agreement with values recently proposed. These results demonstrate the utility of Li(+) drifting in the study of silicon point defect properties in p-type FZ crystals. Finally, a straightforward measurement of the Li(+) compensation depth is shown to yield estimates of the vacancy-related defect concentration in p-type FZ crystals.

  6. Parametric study of two-body floating-point wave absorber

    NASA Astrophysics Data System (ADS)

    Amiri, Atena; Panahi, Roozbeh; Radfar, Soheil

    2016-03-01

    In this paper, we present a comprehensive numerical simulation of a point wave absorber in deep water. Analyses are performed in both the frequency and time domains. The converter is a two-body floating-point absorber (FPA) with one degree of freedom in the heave direction. Its two parts are connected by a linear mass-spring-damper system. The commercial ANSYS-AQWA software used in this study performs well in considering validations. The velocity potential is obtained by assuming incompressible and irrotational flow. As such, we investigated the effects of wave characteristics on energy conversion and device efficiency, including wave height and wave period, as well as the device diameter, draft, geometry, and damping coefficient. To validate the model, we compared our numerical results with those from similar experiments. Our study results can clearly help to maximize the converter's efficiency when considering specific conditions.

  7. Numerical simulation of point defect transport in floating-zone silicon single crystal growth

    NASA Astrophysics Data System (ADS)

    Larsen, T. L.; Jensen, L.; Lüdge, A.; Riemann, H.; Lemke, H.

    2001-08-01

    This work compares simulations of intrinsic point defect transport for a 0.8″ crystal for two different values of the point defect recombination factor, thereafter utilizing the model for two more commercially relevant 4″ crystals, grown with the needle-eye technique. Using this approach to study defect transport in floating-zone configurations is the novelty of this work. The simulation of the thin 0.8″ crystal is compared to the qualitative Voronkov model and DLTS experiments, to give some insights on the applied recombination factors. The work concludes that for large crystals, grown in the vacancy region, the influence of an uncertain recombination factor is not as significant as for smaller crystals grown with a near critical growth parameter.

  8. Quantifying the Impact of Single Bit Flips on Floating Point Arithmetic

    SciTech Connect

    Elliott, James J; Mueller, Frank; Stoyanov, Miroslav K; Webster, Clayton G

    2013-08-01

    In high-end computing, the collective surface area, smaller fabrication sizes, and increasing density of components have led to an increase in the number of observed bit flips. If mechanisms are not in place to detect them, such flips produce silent errors, i.e. the code returns a result that deviates from the desired solution by more than the allowed tolerance and the discrepancy cannot be distinguished from the standard numerical error associated with the algorithm. These phenomena are believed to occur more frequently in DRAM, but logic gates, arithmetic units, and other circuits are also susceptible to bit flips. Previous work has focused on algorithmic techniques for detecting and correcting bit flips in specific data structures, however, they suffer from lack of generality and often times cannot be implemented in heterogeneous computing environment. Our work takes a novel approach to this problem. We focus on quantifying the impact of a single bit flip on specific floating-point operations. We analyze the error induced by flipping specific bits in the most widely used IEEE floating-point representation in an architecture-agnostic manner, i.e., without requiring proprietary information such as bit flip rates and the vendor-specific circuit designs. We initially study dot products of vectors and demonstrate that not all bit flips create a large error and, more importantly, expected value of the relative magnitude of the error is very sensitive on the bit pattern of the binary representation of the exponent, which strongly depends on scaling. Our results are derived analytically and then verified experimentally with Monte Carlo sampling of random vectors. Furthermore, we consider the natural resilience properties of solvers based on the fixed point iteration and we demonstrate how the resilience of the Jacobi method for linear equations can be significantly improved by rescaling the associated matrix.

  9. High-Precision Floating-Point Arithmetic in ScientificComputation

    SciTech Connect

    Bailey, David H.

    2004-12-31

    At the present time, IEEE 64-bit floating-point arithmetic is sufficiently accurate for most scientific applications. However, for a rapidly growing body of important scientific computing applications, a higher level of numeric precision is required: some of these applications require roughly twice this level; others require four times; while still others require hundreds or more digits to obtain numerically meaningful results. Such calculations have been facilitated by new high-precision software packages that include high-level language translation modules to minimize the conversion effort. These activities have yielded a number of interesting new scientific results in fields as diverse as quantum theory, climate modeling and experimental mathematics, a few of which are described in this article. Such developments suggest that in the future, the numeric precision used for a scientific computation may be as important to the program design as are the algorithms and data structures.

  10. Real-time IP-hologram conversion hardware based on floating point DSPs

    NASA Astrophysics Data System (ADS)

    Oi, Ryutaro; Mishina, Tomoyuki; Yamamoto, Kenji; Okui, Makoto

    2009-02-01

    Holography is a 3-D display method that fully satisfies the visual characteristics of the human eye. However, the hologram must be developed in a darkroom under laser illumination. We attempted hologram generation under white light by adopting an integral photography (IP) technique as the input. In this research, we developed a hardware converter to convert IP input (with 120×66 elemental images) to a hologram with high definition television (HDTV) resolution (approximately 2 million pixels). This conversion could be carried out in real time. In this conversion method, each elemental image can be independently extracted and processed. Our hardware contains twenty 300-MHz floating-point digital signal processors (DSPs) operating in parallel. We verified real-time conversion operations by the implemented hardware.

  11. FloPSy - Search-Based Floating Point Constraint Solving for Symbolic Execution

    NASA Astrophysics Data System (ADS)

    Lakhotia, Kiran; Tillmann, Nikolai; Harman, Mark; de Halleux, Jonathan

    Recently there has been an upsurge of interest in both, Search-Based Software Testing (SBST), and Dynamic Symbolic Execution (DSE). Each of these two approaches has complementary strengths and weaknesses, making it a natural choice to explore the degree to which the strengths of one can be exploited to offset the weakness of the other. This paper introduces an augmented version of DSE that uses a SBST-based approach to handling floating point computations, which are known to be problematic for vanilla DSE. The approach has been implemented as a plug in for the Microsoft Pex DSE testing tool. The paper presents results from both, standard evaluation benchmarks, and two open source programs.

  12. Interferometric synthetic aperture microscopy implementation on a floating point multi-core digital signal processer

    NASA Astrophysics Data System (ADS)

    Ahmad, Adeel; Ali, Murtaza; South, Fredrick; Monroy, Guillermo L.; Adie, Steven G.; Shemonski, Nathan; Carney, P. Scott; Boppart, Stephen A.

    2013-03-01

    The transition of optical coherence tomography (OCT) technology from the lab environment towards the more challenging clinical and point-of-care settings is continuing at a rapid pace. On one hand this translation opens new opportunities and avenues for growth, while on the other hand it also presents a new set of challenges and constraints under which OCT systems have to operate. OCT systems in the clinical environment are not only required to be user friendly and easy to operate, but should also be portable, have a smaller form factor coupled with low cost and reduced power consumption. Digital signal processors (DSP) are in a unique position to satisfy the computational requirements for OCT at a much lower cost and power consumption compared to the existing platforms such as CPU and graphics processing units (GPUs). In this work, we describe the implementation of optical coherence tomography (OCT) and interferometric synthetic aperture microscopy (ISAM) processing on a floating point multi-core DSP (C6678, Texas Instruments). ISAM is a computationally intensive data processing technique that is based on the re-sampling of the Fourier space of the data to yield spatially invariant transverse resolution in OCT. Preliminary results indicate that 2DISAM processing at 70,000 A-lines/sec and OCT at 180,000 A-lines/sec can be achieved with the current implementation using available DSP hardware.

  13. Verification of Numerical Programs: From Real Numbers to Floating Point Numbers

    NASA Technical Reports Server (NTRS)

    Goodloe, Alwyn E.; Munoz, Cesar; Kirchner, Florent; Correnson, Loiec

    2013-01-01

    Numerical algorithms lie at the heart of many safety-critical aerospace systems. The complexity and hybrid nature of these systems often requires the use of interactive theorem provers to verify that these algorithms are logically correct. Usually, proofs involving numerical computations are conducted in the infinitely precise realm of the field of real numbers. However, numerical computations in these algorithms are often implemented using floating point numbers. The use of a finite representation of real numbers introduces uncertainties as to whether the properties veri ed in the theoretical setting hold in practice. This short paper describes work in progress aimed at addressing these concerns. Given a formally proven algorithm, written in the Program Verification System (PVS), the Frama-C suite of tools is used to identify sufficient conditions and verify that under such conditions the rounding errors arising in a C implementation of the algorithm do not affect its correctness. The technique is illustrated using an algorithm for detecting loss of separation among aircraft.

  14. Optimal Compression of Floating-Point Astronomical Images Without Significant Loss of Information

    NASA Technical Reports Server (NTRS)

    Pence, William D.; White, R. L.; Seaman, R.

    2010-01-01

    We describe a compression method for floating-point astronomical images that gives compression ratios of 6 - 10 while still preserving the scientifically important information in the image. The pixel values are first preprocessed by quantizing them into scaled integer intensity levels, which removes some of the uncompressible noise in the image. The integers are then losslessly compressed using the fast and efficient Rice algorithm and stored in a portable FITS format file. Quantizing an image more coarsely gives greater image compression, but it also increases the noise and degrades the precision of the photometric and astrometric measurements in the quantized image. Dithering the pixel values during the quantization process greatly improves the precision of measurements in the more coarsely quantized images. We perform a series of experiments on both synthetic and real astronomical CCD images to quantitatively demonstrate that the magnitudes and positions of stars in the quantized images can be measured with the predicted amount of precision. In order to encourage wider use of these image compression methods, we have made available a pair of general-purpose image compression programs, called fpack and funpack, which can be used to compress any FITS format image.

  15. Floating-Point Modules Targeted for Use with RC Compilation Tools

    NASA Technical Reports Server (NTRS)

    Sahin, Ibrahin; Gloster, Clay S.

    2000-01-01

    Reconfigurable Computing (RC) has emerged as a viable computing solution for computationally intensive applications. Several applications have been mapped to RC system and in most cases, they provided the smallest published execution time. Although RC systems offer significant performance advantages over general-purpose processors, they require more application development time than general-purpose processors. This increased development time of RC systems provides the motivation to develop an optimized module library with an assembly language instruction format interface for use with future RC system that will reduce development time significantly. In this paper, we present area/performance metrics for several different types of floating point (FP) modules that can be utilized to develop complex FP applications. These modules are highly pipelined and optimized for both speed and area. Using these modules, and example application, FP matrix multiplication, is also presented. Our results and experiences show, that with these modules, 8-10X speedup over general-purpose processors can be achieved.

  16. Toward a formal verification of a floating-point coprocessor and its composition with a central processing unit

    NASA Technical Reports Server (NTRS)

    Pan, Jing; Levitt, Karl N.; Cohen, Gerald C.

    1991-01-01

    Discussed here is work to formally specify and verify a floating point coprocessor based on the MC68881. The HOL verification system developed at Cambridge University was used. The coprocessor consists of two independent units: the bus interface unit used to communicate with the cpu and the arithmetic processing unit used to perform the actual calculation. Reasoning about the interaction and synchronization among processes using higher order logic is demonstrated.

  17. Desirable floating-point arithmetic and elementary functions for numerical computation

    NASA Technical Reports Server (NTRS)

    Hull, T. E.

    1978-01-01

    The topics considered are: (1) the base of the number system, (2) precision control, (3) number representation, (4) arithmetic operations, (5) other basic operations, (6) elementary functions, and (7) exception handling. The possibility of doing without fixed-point arithmetic is also mentioned. The specifications are intended to be entirely at the level of a programming language such as FORTRAN. The emphasis is on convenience and simplicity from the user's point of view. Conforming to such specifications would have obvious beneficial implications for the portability of numerical software, and for proving programs correct, as well as attempting to provide facilities which are most suitable for the user. The specifications are not complete in every detail, but it is intended that they be complete in spirit - some further details, especially syntatic details, would have to be provided, but the proposals are otherwise relatively complete.

  18. Development of the Kalman filter application and a VHDL model for the AFIT (Air Force Institute of Technology) Floating Point Application Specific Processor (FPASP)

    NASA Astrophysics Data System (ADS)

    Koch, William E.

    1989-12-01

    The Air Force Institute of Technology (AFIT) is conducting research that will lead to the development of a Floating Point application Specific Processor (FPASP). The FPASP architecture is designed around two independent 32 bit data paths that work in tandem to support full IEEE double precision floating point operations, or that can work independently for 32 bit integer processing. Designed to operate at 25 MHz, the FPASP will be capable of performing 25 million floating point operations per second. A rapid prototyping methodology has been developed for the FPASP. A user identifies an application that could benefit from a VLSI solution. An algorithm of the application is translated into FPASP microcode which can then be programmed into the Laser Programmable Read Only Memory (LPROM) of a blank FPASP. The programmed FPASP can then be mounted on a circuit card and installed in a host system where it would function as a hardware accelerator supporting the user application. In the first part of this thesis, a user application, the Kalman Filter algorithm, is translated into FPASP microcode for programming into the FPASP. In part two, the feasibility of using the VHSIC (Very High Speed Integrated Circuitry) Hardware Design Language (VHDL) to model a complete system is demonstrated by developing a register transfer level model of the FPASP.

  19. Implementation of the DAST ARW II control laws using an 8086 microprocessor and an 8087 floating-point coprocessor. [drones for aeroelasticity research

    NASA Technical Reports Server (NTRS)

    Kelly, G. L.; Berthold, G.; Abbott, L.

    1982-01-01

    A 5 MHZ single-board microprocessor system which incorporates an 8086 CPU and an 8087 Numeric Data Processor is used to implement the control laws for the NASA Drones for Aerodynamic and Structural Testing, Aeroelastic Research Wing II. The control laws program was executed in 7.02 msec, with initialization consuming 2.65 msec and the control law loop 4.38 msec. The software emulator execution times for these two tasks were 36.67 and 61.18, respectively, for a total of 97.68 msec. The space, weight and cost reductions achieved in the present, aircraft control application of this combination of a 16-bit microprocessor with an 80-bit floating point coprocessor may be obtainable in other real time control applications.

  20. Stools - floating

    MedlinePlus

    ... absorption of nutrients ( malabsorption ) or too much gas (flatulence). Considerations Most causes of floating stools are harmless. ... Bailey J. FPIN's Clinical Inquiries: Effective management of flatulence. Am Fam Physician Ohge H, Levitt MD. Intestinal ...

  1. 40 CFR 426.50 - Applicability; description of the float glass manufacturing subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... float glass manufacturing subcategory. 426.50 Section 426.50 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GLASS MANUFACTURING POINT SOURCE CATEGORY Float Glass Manufacturing Subcategory § 426.50 Applicability; description of the float...

  2. 40 CFR 426.50 - Applicability; description of the float glass manufacturing subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... float glass manufacturing subcategory. 426.50 Section 426.50 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GLASS MANUFACTURING POINT SOURCE CATEGORY Float Glass Manufacturing Subcategory § 426.50 Applicability; description of the float...

  3. Tank Tests of Twin Seaplane Floats

    NASA Technical Reports Server (NTRS)

    Herrman, H; Kempf, G; Kloess, H

    1928-01-01

    The following report contains the most essential data for the hydrodynamic portion of the twin-float problem. The following points were successfully investigated: 1) difference between stationary and nonstationary flow; 2) effect of the shape of the step; 3) effect of distance between floats; 4) effect of nose-heavy and tail-heavy moments; 5) effect of the shape of floats; 6) maneuverability.

  4. WindWaveFloat

    SciTech Connect

    Weinstein, Alla

    2011-11-01

    Presentation from the 2011 Water Peer Review includes in which principal investigator Alla Weinstein discusses project progress in development of a floating offshore wind structure - the WindFloat - and incorporation therin of a Spherical Wave Energy Device.

  5. Floating: sink or swim.

    PubMed

    Pronger, L

    1995-12-01

    Budget restrictions, fewer human resources and fluctuating patient populations have combined to increase the practice of floating general duty nurses. Floating occurs when a nurse from an overstaffed unit, based on patient load, is required to work in another unit that is understaffed. Floating is not a new practice, but it has always been an emotionally charged issue. Today, with more float pool nurses seeking the security of a permanent position in a home unit, the issue has increased in intensity. PMID:8713148

  6. The Design of Floats

    NASA Technical Reports Server (NTRS)

    Sottorf, W

    1938-01-01

    Following a summary of the multiplicity of domestic and foreign floats and a brief enumeration of the requirements of floats, the essential form parameters and their effect on the qualities of floats are detailed. On this basis a standard float design is developed which in model families with varying length/beam ratio and angle of dead rise is analyzed by an experimental method which permits its best utilization on any airplane.

  7. "Floating shoulder" injuries.

    PubMed

    Heng, Kenneth

    2016-12-01

    "Floating shoulder" is a rare injury complex resulting from high-energy blunt force trauma to the shoulder, resulting in scapulothoracic dissociation. It is commonly associated with catastrophic neurovascular injury. Two cases of motorcyclists with floating shoulder injuries are described. PMID:26961729

  8. Float Zone Workshop

    NASA Technical Reports Server (NTRS)

    Naumann, R. J.

    1980-01-01

    A summary of the Analytical Float Zone Experiment System (AFZES) concept is presented. The types of experiments considered for such a facility are discussed. Reports from various industrial producers and users of float zone material are presented. Special emphasis is placed on state-of-the-art developments in low gravity manufacturing and their applications to space processing.

  9. Impact on floating membranes

    NASA Astrophysics Data System (ADS)

    Vandenberghe, Nicolas; Duchemin, Laurent

    2016-05-01

    When impacted by a rigid body, a thin elastic membrane with negligible bending rigidity floating on a liquid pool deforms. Two axisymmetric waves radiating from the impact point propagate. First, a longitudinal wave front, associated with in-plane deformation of the membrane and traveling at constant speed, separates an outward stress-free domain from a stretched domain. Then, in the stretched domain a dispersive transverse wave travels at a speed that depends on the local stretching rate. The dynamics is found to be self-similar in time. Using this property, we show that the wave dynamics is similar to the capillary waves that propagate at a liquid-gas interface but with a surface tension coefficient that depends on impact speed. During wave propagation, we observe the development of a buckling instability that gives rise to radial wrinkles. We address the dynamics of this fluid-body system, including the rapid deceleration of an impactor of finite mass, an issue that may have applications in the domain of absorption of impact energy.

  10. Floating emitter solar cell

    NASA Technical Reports Server (NTRS)

    Chih, Sah (Inventor); Cheng, Li-Jen (Inventor)

    1987-01-01

    A front surface contact floating emitter solar cell transistor is provided in a semiconductor body (n-type), in which floating emitter sections (p-type) are diffused or implanted in the front surface. Between the emitter sections, a further section is diffused or implanted in the front surface, but isolated from the floating emitter sections, for use either as a base contact to the n-type semiconductor body, in which case the section is doped n+, or as a collector for the adjacent emitter sections.

  11. Floating Magnet Demonstration.

    ERIC Educational Resources Information Center

    Wake, Masayoshi

    1990-01-01

    A room-temperature demonstration of a floating magnet using a high-temperature superconductor is described. The setup and operation of the apparatus are described. The technical details of the effect are discussed. (CW)

  12. Float-in powerhouses

    SciTech Connect

    Makela, G.A.

    1983-06-01

    The nation's inland waterway system affords a means of transporting large objects limited only by channel depth, size of locks and bridge clearances. The concept of prefabricating standardized, hydroelectric powerhouses at shipyards, transporting them along the inland waterways and installing them at navigation dams without powerhouses was examined for the McClellan-Kerr Arkansas River Navigation system. It was found that construction costs for the float-in design was very close to those of conventional sitebuilt design. Experience at Greenup Dam on the Ohio River where a float-in powerhouse has been installed indicated that construction time could be reduced if the float-in design was used. This time saving, use of standardized designs and construction of the float-in module at a shipyard may offer advantages that should be examined in more detailed when the power potential of the nation's low navigation dams is assessed.

  13. Concrete production floating platforms

    SciTech Connect

    Letourneur, O.; Falcimaigne, J.

    1981-01-01

    The floating production platforms operating in the North Sea are adapted from drilling semisubmersibles which allow only a limited payload capacity. Experience of concrete production platforms constructed for the North Sea has led Sea Tank Co. to propose a floating platform which offers large payload and oil storage capacities similar to those of existing fixed platforms. Sea Tank Co. and Institut Francais du Petrole joined forces in early 1976 to study the feasibility of a concrete floating production platform incorporating the structure and the production riser together. The results of this 3-yr program show that the concrete floating structure is economically attractive for permanent utilization on a production site. Furthermore, concrete has definite advantages over other materials, in its long term behavior.

  14. Micromechanisms with floating pivot

    DOEpatents

    Garcia, Ernest J.

    2001-03-06

    A new class of tilting micromechanical mechanisms have been developed. These new mechanisms use floating pivot structures to relieve some of the problems encountered in the use of solid flexible pivots.

  15. Stabilized floating platforms

    DOEpatents

    Thomas, David G.

    1976-01-01

    The subject invention is directed to a floating platform for supporting nuclear reactors and the like at selected offshore sites. The platform is provided with a stabilizer mechanism which significantly reduces the effects of wave action upon the platform and which comprises a pair of relatively small floats attached by rigid booms to the platform at locations spaced therefrom for reducing wave pitch, acceleration, and the resonance period of the wave.

  16. 40 CFR 426.50 - Applicability; description of the float glass manufacturing subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... float glass manufacturing subcategory. 426.50 Section 426.50 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) GLASS MANUFACTURING POINT SOURCE CATEGORY Float Glass Manufacturing Subcategory § 426.50 Applicability; description of the float...

  17. 40 CFR 426.50 - Applicability; description of the float glass manufacturing subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... float glass manufacturing subcategory. 426.50 Section 426.50 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) GLASS MANUFACTURING POINT SOURCE CATEGORY Float Glass Manufacturing Subcategory § 426.50 Applicability; description of the float...

  18. 40 CFR 426.50 - Applicability; description of the float glass manufacturing subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... float glass manufacturing subcategory. 426.50 Section 426.50 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) GLASS MANUFACTURING POINT SOURCE CATEGORY Float Glass Manufacturing Subcategory § 426.50 Applicability; description of the float...

  19. Floating nut retention system

    NASA Technical Reports Server (NTRS)

    Charles, J. F.; Theakston, H. A. (Inventor)

    1980-01-01

    A floating nut retention system includes a nut with a central aperture. An inner retainer plate has an opening which is fixedly aligned with the nut aperture. An outer retainer member is formed of a base plate having an opening and a surface adjacent to a surface of the inner retainer plate. The outer retainer member includes a securing mechanism for retaining the inner retainer plate adjacent to the outer retainer member. The securing mechanism enables the inner retainer plate to float with respect to the outer retainer number, while simultaneously forming a bearing surface for inner retainer plate.

  20. Tethered float liquid level sensor

    DOEpatents

    Daily, III, William Dean

    2016-09-06

    An apparatus for sensing the level of a liquid includes a float, a tether attached to the float, a pulley attached to the tether, a rotation sensor connected to the pulley that senses vertical movement of said float and senses the level of the liquid.

  1. Compound floating pivot micromechanisms

    DOEpatents

    Garcia, Ernest J.

    2001-04-24

    A new class of tilting micromechanical mechanisms have been developed. These new mechanisms use compound floating pivot structures to attain far greater tilt angles than are practical using other micromechanical techniques. The new mechanisms are also capable of bi-directional tilt about multiple axes.

  2. Floating platform with monolithically formed float members and platform

    SciTech Connect

    Finsterwalder, U.

    1981-06-30

    Floating platforms for various offshore facilities are formed of float members monolithically connected to a superposed platform. The float members are spherically shaped and are formed of reinforced or prestressed concrete. The platform can be a hollow planar member or it can be curved in one or two directions, and the platforms are formed of prestressed concrete. Cylindrical shafts can be used to connect the spherically shaped floats and the platform. Individual floating platforms can be connected by expansion joints and used as a runway. The float members can be constructed at the shoreline, launched into the water and held in a regular pattern while decked over with the platform. After completion of the construction procedure, the floating platform can be moved to an offshore location for use.

  3. Freely floating smectic films.

    PubMed

    May, Kathrin; Harth, Kirsten; Trittel, Torsten; Stannarius, Ralf

    2014-05-19

    We have investigated the dynamics of freely floating smectic bubbles using high-speed optical imaging. Bubbles in the size range from a few hundred micrometers to several centimeters were prepared from collapsing catenoids. They represent ideal model systems for the study of thin-film fluid dynamics under well-controlled conditions. Owing to the internal smectic layer structure, the bubbles combine features of both soap films and vesicles in their unique shape dynamics. From a strongly elongated initial shape after pinch-off, they relax towards the spherical equilibrium, first by a slow redistribution of the smectic layers, and finally by weak, damped shape oscillations. In addition, we describe the rupture of freely floating smectic bubbles, and the formation and stability of smectic filaments. PMID:24692347

  4. Float processing of high-temperature complex silicate glasses and float baths used for same

    NASA Technical Reports Server (NTRS)

    Cooper, Reid Franklin (Inventor); Cook, Glen Bennett (Inventor)

    2000-01-01

    A float glass process for production of high melting temperature glasses utilizes a binary metal alloy bath having the combined properties of a low melting point, low reactivity with oxygen, low vapor pressure, and minimal reactivity with the silicate glasses being formed. The metal alloy of the float medium is exothermic with a solvent metal that does not readily form an oxide. The vapor pressure of both components in the alloy is low enough to prevent deleterious vapor deposition, and there is minimal chemical and interdiffusive interaction of either component with silicate glasses under the float processing conditions. Alloys having the desired combination of properties include compositions in which gold, silver or copper is the solvent metal and silicon, germanium or tin is the solute, preferably in eutectic or near-eutectic compositions.

  5. The Floating Ball Paradox

    NASA Astrophysics Data System (ADS)

    Wente, Henry C.

    2008-11-01

    In capillary theory there are two kinds of surface tension. There is the surface tension at the interface between two immiscible fluids. Thomas Young [9] also allowed for there to be a surface tension associated with a liquid-solid interface. He proceeded to use a balance of forces argument to derive the well-known contact angle condition along a liquid-liquid-solid intersection. The validity of this argument has recently been called into question by R. Finn [6]. A floating ball experiment discussed in that paper leads to an apparent paradox. We address this issue.

  6. Does It Sink or Float?

    ERIC Educational Resources Information Center

    McDonald, Judith Richards

    2012-01-01

    This activity is designed to teach prekindergarten to second grade students about the concept of sink or float through an inquiry activity. Students will use familiar objects to predict and test the properties of sink and float. Background information is offered to teachers to assist them with this activity. This lesson begins with an engaging…

  7. Floating mirror mount

    SciTech Connect

    Koop, D.E.

    1989-01-03

    This patent describes a floating mirror mount for a mirror of a laser is described consisting of: a mirror having a front surface and a back surface, a keeper encircling the mirror and having a peripheral flange engaging the front surface of the mirror when the mirror is not installed in a laser, a retainer positioned rearwardly of the back surface of the mirror and connected to the keeper and having a spring seating surface, spring means engageable with the spring seating surface of the retainer for exerting a resilient biasing force on the mirror, and fastening means for connecting the retainer to the mirror positioning structure of the laser on installation of the mirror mount in the laser.

  8. Floating Silicon Method

    SciTech Connect

    Kellerman, Peter

    2013-12-21

    The Floating Silicon Method (FSM) project at Applied Materials (formerly Varian Semiconductor Equipment Associates), has been funded, in part, by the DOE under a “Photovoltaic Supply Chain and Cross Cutting Technologies” grant (number DE-EE0000595) for the past four years. The original intent of the project was to develop the FSM process from concept to a commercially viable tool. This new manufacturing equipment would support the photovoltaic industry in following ways: eliminate kerf losses and the consumable costs associated with wafer sawing, allow optimal photovoltaic efficiency by producing high-quality silicon sheets, reduce the cost of assembling photovoltaic modules by creating large-area silicon cells which are free of micro-cracks, and would be a drop-in replacement in existing high efficiency cell production process thereby allowing rapid fan-out into the industry.

  9. Floating into Deep Space

    NASA Astrophysics Data System (ADS)

    La Frenais, R.; Saraceno, T.; Powell, J.

    2014-04-01

    Is it possible for spaceflight to become more sustainable? Artist and architect Tomas Saraceno proposes a long-term artscience research project based on his initial work with solar balloons to join with the efforts of engineers such as John Powell, working on the Airship to Orbit experiments, which describe a three stage process of using airships to fly to a large suborbital "Dark Sky Station' then literally floating into orbit with additional electrical and chemical propulsion. (See: http://www.jpaerospace.com) In his artworks Tomás Saraceno proposes cell-like flying cities as possible architectonic living spaces in direct reference to Buckminster Fuller's Cloud Nine (circa 1960). The fantastic architectural utopia Cloud Nine consists of a freely floating sphere measuring one mile in diameter that offers living space to several autonomous communities encompassing thousands of inhabitants each. The notion of the cloud is essential to the artist's work. The cloud as metaphor stands for artistic intention, for the meaning of territory and border in today's (urban) society, and for exploring possibilities for the sustainable development of the human living environment. In Saraceno's work this environment is not limited to the earth, but is explicitly conceived to reach into outer space. (Biomimetic Constructions- On the works of Tomás Saraceno By Katharina Schlüter) Saraceno is also interested in human factors experiments using his existing constructions as analogue environments for living on Mars and is proposing carry out a series of workshops, experiments and solar balloon launces in White Sands desert in early 2016 in collaboration with the curator Dr Rob La Frenais, the Rubin Center at The University of Texas at El Paso and various scientific partners.

  10. Liquid encapsulated float zone process and apparatus

    NASA Technical Reports Server (NTRS)

    Naumann, Robert J. (Inventor); Frazier, Donald O. (Inventor); Lehoczky, Sandor L. (Inventor); Vlasse, Marcus (Inventor); Facemire, Barbara R. (Inventor)

    1988-01-01

    The process and apparatus for growing crystals using float zone techniques are described. A rod of crystalline materials is disposed in a cylindrical container, leaving a space between the rod and container walls. This space is filled with an encapsulant, selected to have a slightly lower melting point than the crystalline material. The rod is secured to a container end cap at one end and to a shaft at its other end. A piston slides over the rod and provides pressure to prevent loss of volatile components upon melting of the rod. Prior to melting the rod the container is first heated to melt the encapsulant, with any off-gas from this step being vented to a cavity behind the piston. The piston moves slightly forward owing to volume change upon melting of the encapsulant, and the vent passageway is closed. The container is then moved longitudinally through a heated zone to progressively melt sections of the rod as in conventional float zone processes. The float zone technique may be used in the microgravity environment of space.

  11. Ipsilateral Floating Hip and Floating Knee - A Rare Entity

    PubMed Central

    Yashavantha Kumar, C; Nalini, K B; Nagaraj, Prashanth; Jawali, Abhijith

    2013-01-01

    Introduction: Ipsilateral floating hip and floating knee are very rare injuries. These injuries so uncommon that only three cases of similar kind have been reported. These injuries are due to high velocity injuries following motor vehicle accidents. Management of such complex injuries is a challenging task even in experienced hands as there are no standard treatment guidelines for such fractures. Case Report: We hereby report a 20 yr old male who sustained ipsilateral floating hip and ipsilateral floating knee injuries following motor vehicle accident. Patient was stabilized initially and later taken up for surgery. Patient was treated with interlocking nail for femur and tibia in the same sitting whereas acetabulam fracture was managed conservatively. At five months all the fractures united well with restoration of good range of motion in both hip and knee Conclusion: Ipsilateral floating knee and floating hip are very rare injuries seen following high velocity motor vehicle accidents. There are no standard guidelines for treatment of those fractures as only a few cases of similar kind have been reported in literature. Early fixation and aggressive mobilization ensures fracture union and fewer complications. PMID:27298908

  12. Floating orbital molecular dynamics simulations.

    PubMed

    Perlt, Eva; Brüssel, Marc; Kirchner, Barbara

    2014-04-21

    We introduce an alternative ab initio molecular dynamics simulation as a unification of Hartree-Fock molecular dynamics and the floating orbital approach. The general scheme of the floating orbital molecular dynamics method is presented. Moreover, a simple but sophisticated guess for the orbital centers is provided to reduce the number of electronic structure optimization steps at each molecular dynamics step. The conservation of total energy and angular momentum is investigated in order to validate the floating orbital molecular dynamics approach with and without application of the initial guess. Finally, a water monomer and a water dimer are simulated, and the influence of the orbital floating on certain properties like the dipole moment is investigated. PMID:24600690

  13. Electrically floating, near vertical incidence, skywave antenna

    SciTech Connect

    Anderson, Allen A.; Kaser, Timothy G.; Tremblay, Paul A.; Mays, Belva L.

    2014-07-08

    An Electrically Floating, Near Vertical Incidence, Skywave (NVIS) Antenna comprising an antenna element, a floating ground element, and a grounding element. At least part of said floating ground element is positioned between said antenna element and said grounding element. The antenna is separated from the floating ground element and the grounding element by one or more electrical insulators. The floating ground element is separated from said antenna and said grounding element by one or more electrical insulators.

  14. Skylab floating ice experiment

    NASA Technical Reports Server (NTRS)

    Campbell, W. J. (Principal Investigator); Ramseier, R. O.; Weaver, R. J.; Weeks, W. F.

    1975-01-01

    The author has identified the following significant results. Coupling of the aircraft data with the ground truth observations proved to be highly successful with interesting results being obtained with IR and SLAR passive microwave techniques, and standard photography. Of particular interest were the results of the PMIS system which operated at 10.69 GHz with both vertical and horizontal polarizations. This was the first time that dual polarized images were obtained from floating ice. In both sea and lake ice, it was possible to distinguish a wide variety of thin ice types because of their large differences in brightness temperatures. It was found that the higher brightness temperature was invariably obtained in the vertically polarized mode, and as the age of the ice increases the brightness temperature increases in both polarizations. Associated with this change in age, the difference in temperature was observed as the different polarizations decreased. It appears that the horizontally polarized data is the most sensitive to variations in ice type for both fresh water and sea ice. The study also showed the great amount of information on ice surface roughness and deformation patterns that can be obtained from X-band SLAR observations.

  15. Floating wind turbine system

    NASA Technical Reports Server (NTRS)

    Viterna, Larry A. (Inventor)

    2009-01-01

    A floating wind turbine system with a tower structure that includes at least one stability arm extending therefrom and that is anchored to the sea floor with a rotatable position retention device that facilitates deep water installations. Variable buoyancy for the wind turbine system is provided by buoyancy chambers that are integral to the tower itself as well as the stability arm. Pumps are included for adjusting the buoyancy as an aid in system transport, installation, repair and removal. The wind turbine rotor is located downwind of the tower structure to allow the wind turbine to follow the wind direction without an active yaw drive system. The support tower and stability arm structure is designed to balance tension in the tether with buoyancy, gravity and wind forces in such a way that the top of the support tower leans downwind, providing a large clearance between the support tower and the rotor blade tips. This large clearance facilitates the use of articulated rotor hubs to reduced damaging structural dynamic loads. Major components of the turbine can be assembled at the shore and transported to an offshore installation site.

  16. Floating into Thin Air

    SciTech Connect

    Hazi, A U

    2007-02-06

    On May 18, 2005, a giant helium balloon carrying the High Energy Focusing Telescope (HEFT) sailed into the spring sky over the deserts of New Mexico. The spindly steel and aluminum gondola that houses the optics, detectors, and other components of the telescope floated for 25 hours after its launch from Fort Sumner, New Mexico. For 21 of those hours, the balloon was nearly 40 kilometers above Earth's surface--almost four times higher than the altitude routinely flown by commercial jet aircraft. In the upper reaches of Earth's atmosphere, HEFT searched the universe for x-ray sources from highly energetic objects such as binary stars, galaxy clusters, and supermassive black holes. Before landing in Arizona, the telescope observed and imaged a dozen scientific targets by capturing photons emitted from these objects in the high-energy (hard) x-ray range (above 10 kiloelectronvolts). Among these targets were the Crab synchrotron nebula, the black hole Cygnus X-1 (one of the brightest x-ray sources in the sky), and the blazar 3C454.3. The scientific data gathered from these targets are among the first focused hard x-ray images returned from high altitudes.

  17. The Research of Road Traffic Based on Floating Car Data

    NASA Astrophysics Data System (ADS)

    Zhang, Junyou; Jian, Meng; Tang, Rui

    Based on the analysis of floating car traffic information acquisition and processing system structure and construction frame, combining the Zibo floating car features and road conditions, using historical data provided by Zibo city bus companies, adopting the ArcGIS Engine of ESRI company as a map components, putting forward the nearest point estimate map matching algorithms, combining data fusion technology based on Kalman filter and road running speed calibration algorithm, predicting road traffic running status in certain period and express it in the GIS map, this paper completed the design, the practice has proved the suggested method is feasible.

  18. Orthogonal test and experimental study on fire floating pump

    NASA Astrophysics Data System (ADS)

    Liu, J. R.; Zheng, J. F.; Fu, D. P.; Wang, P.

    2013-12-01

    In order to develop high efficiency fire floating pump, 250YYB-250 fire floating pump was taken as an example. The orthogonal experiment of L9 (34), which contains factors with three levels of blade numbers of impeller, outlet angle, impeller fold-angle, was performed to design nine types of impellers. Numerical simulation of whole flow field based on Fluent was adopted to perform an orthogonal test, the order of geometric parameters affects the performance of fire floating pump with complex impeller. The best design scheme for pump model was acquired. Meanwhile, the optimized design scheme was determined, and corresponding test was carried out. It demonstrated that the efficiency of the final optimal design model pump at rated flow point is of 85%. The efficiency is higher than the national standards, which verified the feasibility of the method of orthogonal design in pump design.

  19. 14 CFR 25.529 - Hull and main float landing conditions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... is directed inward perpendicularly to the plane of symmetry at a point midway between the keel and... symmetry midway between the keel and chine lines of the float, at the same longitudinal station as...

  20. 14 CFR 25.529 - Hull and main float landing conditions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... is directed inward perpendicularly to the plane of symmetry at a point midway between the keel and... symmetry midway between the keel and chine lines of the float, at the same longitudinal station as...

  1. 14 CFR 23.529 - Hull and main float landing conditions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... as the upward component but is directed inward perpendicularly to the plane of symmetry at a point..., perpendicularly to the plane of symmetry midway between the keel and chine lines of the float, at the...

  2. 14 CFR 23.529 - Hull and main float landing conditions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... as the upward component but is directed inward perpendicularly to the plane of symmetry at a point..., perpendicularly to the plane of symmetry midway between the keel and chine lines of the float, at the...

  3. Tank Tests of Models of Floats for Single-float Seaplanes First Series.

    NASA Technical Reports Server (NTRS)

    Parkinson, J B

    1936-01-01

    Large models of the Mark V and Mark VI floats used for single float seaplanes (National Advisory Committee for Aeronautics (NACA) models 41-A and 41-B, respectively) were tested in the NACA tank to provide general test data for typical single floats and a basis for possible improvements of their form. The resistance of model 41-B was greater than that of model 41-A, either when free to trim or at the best trim angle for each. The resistance of model 35-B (a pointed step hull tested free to trim) was less than either of the models at the hump speed, greater at intermediate planing speeds, and less at the speeds and loads near get-away, although the spray was generally worse owing to the absence of transverse flare. The results of the fixed-trim tests of model 41-A were cross plotted to obtain data at the angle for zero trimming moment and at the best trim angle. The trims assumed by models 41-A and 41-B, when tested free to trim, were found to be excessive at the hump speed. The corresponding trim of model 35-B was found to be approximately 3 degrees lower because of the lower angle of afterbody keel used in this model, and the maximum hump resistance was 15 percent lower.

  4. 40 CFR 65.45 - External floating roof converted into an internal floating roof.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 15 2011-07-01 2011-07-01 false External floating roof converted into an internal floating roof. 65.45 Section 65.45 Protection of Environment ENVIRONMENTAL PROTECTION... External floating roof converted into an internal floating roof. The owner or operator who elects...

  5. 40 CFR 65.45 - External floating roof converted into an internal floating roof.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 16 2014-07-01 2014-07-01 false External floating roof converted into an internal floating roof. 65.45 Section 65.45 Protection of Environment ENVIRONMENTAL PROTECTION... External floating roof converted into an internal floating roof. The owner or operator who elects...

  6. 40 CFR 65.45 - External floating roof converted into an internal floating roof.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 16 2012-07-01 2012-07-01 false External floating roof converted into an internal floating roof. 65.45 Section 65.45 Protection of Environment ENVIRONMENTAL PROTECTION... External floating roof converted into an internal floating roof. The owner or operator who elects...

  7. 40 CFR 65.45 - External floating roof converted into an internal floating roof.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false External floating roof converted into an internal floating roof. 65.45 Section 65.45 Protection of Environment ENVIRONMENTAL PROTECTION... External floating roof converted into an internal floating roof. The owner or operator who elects...

  8. 40 CFR 65.45 - External floating roof converted into an internal floating roof.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 16 2013-07-01 2013-07-01 false External floating roof converted into an internal floating roof. 65.45 Section 65.45 Protection of Environment ENVIRONMENTAL PROTECTION... External floating roof converted into an internal floating roof. The owner or operator who elects...

  9. Designing seaplane hulls and floats

    NASA Technical Reports Server (NTRS)

    Benoit,

    1926-01-01

    Experimental data, such as the results of tank tests of models, render it possible to predict, at least in principle, as to how a hull or float of a given shape will comport itself. We will see further along, however, how uncertain these methods are and how they leave room for empiricism, which will reign for a long time yet in seaplane research bureaus.

  10. Flinking: Neither Floating nor Sinking.

    ERIC Educational Resources Information Center

    Wilson, Roger B.

    1993-01-01

    Describes an activity that challenges students to make an object that, when released under water, does not float up or sink down. The main concept this activity investigates is the density of ordinary objects in comparison to the density of water. (PR)

  11. Spectral analysis of Floating Car Data

    NASA Astrophysics Data System (ADS)

    Gössel, F.; Michler, E.; Wrase, B.

    2003-05-01

    Floating Car Data (FCD) are one important data source in traffic telematic systems. The original variable in these systems is the vehicle velocity. The paper analyses the measured value "vehicle velocity" by methods of information technology. Consequences for processing, transmission and storage of FCD under condition of limited resources are discussed. Starting point of the investigation is the analysis of spectral characteristics of velocity-time-profiles. The spectra are determined by the Discrete Fourier Transform (DFT) from measurement data and simulation data of a microscopic traffic model. One essential property of velocity-time-profiles is their low-pass characteristic. The resulting cut-off-frequency is comparatively small and depends on the traffic scenario. Conclusions concerning the necessary sample rate in FCD systems and the processing of raw data are discussed. Finally the transinformation of velocity-time-profiles is analysed. This results in similar values for an optimal sample rate of FCD systems under condition of limited transmission capacity.

  12. Can flexibility help you float?

    NASA Astrophysics Data System (ADS)

    Burton, L. J.; Bush, J. W. M.

    2012-10-01

    We consider the role of flexibility in the weight-bearing characteristics of bodies floating at an interface. Specifically, we develop a theoretical model for a two-dimensional thin floating plate that yields the maximum stable plate load and optimal stiffness for weight support. Plates small relative to the capillary length are primarily supported by surface tension, and their weight-bearing potential does not benefit from flexibility. Above a critical size comparable to the capillary length, flexibility assists interfacial flotation. For plates on the order of and larger than the capillary length, deflection from an initially flat shape increases the force resulting from hydrostatic pressure, allowing the plate to support a greater load. In this large plate limit, the shape that bears the most weight is a semicircle, which displaces the most fluid above the plate for a fixed plate length. Exact results for maximum weight-bearing plate shapes are compared to analytic approximations made in the limits of large and small plate sizes. The value of flexibility for floating to a number of biological organisms is discussed in light of our study.

  13. Instability of floating extensional flows

    NASA Astrophysics Data System (ADS)

    Sayag, Roiy; Worster, Grae

    2015-11-01

    We study the propagation of a viscous fluid over a thin layer of a denser and inviscid fluid. The viscous fluid is released axisymmetrially at constant flux, and is driven by gravity. Near the origin, where the viscous layer is thick, the flow is dominated by vertical shear. In the outer region where the viscous layer is thinner, it floats over the inviscid layer and the dominant stress is extensional. The floating region of such flows remains axisymmetric when the viscous fluid is Newtonian. In contrast, when the viscous fluid is non Newtonian, the floating region can be distributed in an array of extensional tongues. We use experimental and theoretical analysis to study the symmetry breaking of the extensional region. Experiments using polymeric fluids show that the characteristic wavelength of the tongues increases with flux. Theoretically, we model the symmetry breaking as flow instability of a power-law fluid that becomes Newtonian at low strain rates. Our model predicts unstable modes at the strongly non-Newtonian limit, and stable, axisymmetric mode in the Newtonian limit.

  14. Dragging a floating horizontal cylinder

    NASA Astrophysics Data System (ADS)

    Lee, Duck-Gyu; Kim, Ho-Young

    2010-11-01

    A cylinder immersed in a fluid stream experiences a drag, and it is well known that the drag coefficient is a function of the Reynolds number only. Here we study the force exerted on a long horizontal cylinder that is dragged perpendicular to its axis while floating on an air-water interface with a high Reynolds number. In addition to the flow-induced drag, the floating body is subjected to capillary forces along the contact line where the three phases of liquid/solid/gas meet. We first theoretically predict the meniscus profile around the horizontally moving cylinder assuming the potential flow, and show that the profile is in good agreement with that obtained experimentally. Then we compare our theoretical predictions and experimental measurement results for the drag coefficient of a floating horizontal cylinder that is given by a function of the Weber number and the Bond number. This study can help us to understand the horizontal motion of partially submerged objects at air-liquid interface, such as semi-aquatic insects and marine plants.

  15. Float zone experiments in space

    NASA Technical Reports Server (NTRS)

    Verhoeven, J. D.; Noack, M. A.; Gill, W. N.; Hau, C. C.

    1984-01-01

    The molten zone/freezing crystal interface system and all the mechanisms were examined. If Marangoni convection produces oscillatory flows in the float zone of semiconductor materials, such as silicon, then it is unlikely that superior quality crystals can be grown in space using this process. The major goals were: (1) to determine the conditions for the onset of Marangoni flows in molten tin, a model system for low Prandtl number molten semiconductor materials; (2) to determine whether the flows can be suppressed by a thin oxide layer; and (3) based on experimental and mathematical analysis, to predict whether oscillatory flows will occur in the float zone silicon geometry in space, and if so, could it be suppressed by thin oxide or nitride films. Techniques were developed to analyze molten tin surfaces in a UHV system in a disk float zone geometry to minimize buoyancy flows. The critical Marangoni number for onset of oscillatory flows was determined to be greater than 4300 on atomically clean molten tin surfaces.

  16. 14 CFR 27.753 - Main float design.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Main float design. 27.753 Section 27.753... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 27.753 Main float design. (a) Bag floats. Each bag float must be designed to withstand— (1) The maximum pressure...

  17. 14 CFR 29.753 - Main float design.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Main float design. 29.753 Section 29.753... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 29.753 Main float design. (a) Bag floats. Each bag float must be designed to withstand— (1) The maximum pressure...

  18. 14 CFR 29.753 - Main float design.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Main float design. 29.753 Section 29.753 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 29.753 Main float design. (a) Bag floats. Each bag float...

  19. 14 CFR 27.753 - Main float design.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Main float design. 27.753 Section 27.753... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 27.753 Main float design. (a) Bag floats. Each bag float must be designed to withstand— (1) The maximum pressure...

  20. Modeling International Space Station (ISS) Floating Potentials

    NASA Technical Reports Server (NTRS)

    Ferguson, Dale C.; Gardner, Barbara

    2002-01-01

    The floating potential of the International Space Station (ISS) as a function of the electron current collection of its high voltage solar array panels is derived analytically. Based on Floating Potential Probe (FPP) measurements of the ISS potential and ambient plasma characteristics, it is shown that the ISS floating potential is a strong function of the electron temperature of the surrounding plasma. While the ISS floating potential has so far not attained the pre-flight predicted highly negative values, it is shown that for future mission builds, ISS must continue to provide two-fault tolerant arc-hazard protection for astronauts on EVA.

  1. Floating patella associated with lymphoedema

    PubMed Central

    Vun, Shen Hwa; Bayam, Levent; Drampalos, Efstathios; Jesry, Mohammed; Fadel, George

    2015-01-01

    Ipsilateral injury of more than one component of the knee extensor apparatus is rare. It is mostly associated with previous trauma, surgery, immunosuppression therapy and systemic disease. We present the first documented case of a spontaneous bifocal disruption of the knee extensor apparatus (i.e. floating patella) associated with lymphoedema. This case highlights the importance of considering lymphoedema as another risk factor for rupture of the knee extensor apparatus. It also highlights the importance of assessing all components of the knee extensor apparatus in patients presenting with acute knee injuries. PMID:25802253

  2. Wave drag on floating bodies

    PubMed Central

    Le Merrer, Marie; Clanet, Christophe; Quéré, David; Raphaël, Élie; Chevy, Frédéric

    2011-01-01

    We measure the deceleration of liquid nitrogen drops floating at the surface of a liquid bath. On water, the friction force is found to be about 10 to 100 times larger than on a solid substrate, which is shown to arise from wave resistance. We investigate the influence of the bath viscosity and show that the dissipation decreases as the viscosity is increased, owing to wave damping. The measured resistance is well predicted by a model imposing a vertical force (i.e., the drop weight) on a finite area, as long as the wake can be considered stationary. PMID:21876186

  3. Floating platform well production apparatus

    SciTech Connect

    Nobileau, P.C.

    1980-10-21

    A plurality of wells are clustered around a central riser which is maintained under tension from a floating platform. A plurality of spiders on the riser carry funnels in vertical alignment with the wells. The funnels are sufficiently large to permit the passage of wellhead connectors and master block valves, and the production risers include centralizers which brace the production riser from the funnels through a limited vertical range. Tensioning of the production riser is with a lower force and through a limited range which precludes disengagement of the centralizers from the funnel. Some centralizers are located to facilitate entry and attachment to the wellhead.

  4. Development of hollow/porous floating beads of metoprolol for pulsatile drug delivery.

    PubMed

    Taranalli, Sangmesh S; Dandagi, Panchaxari M; Mastiholimath, Vinayak S

    2015-06-01

    The purpose of this work was to develop hollow calcium pectinate beads for floating pulsatile release of metoprolol tartrate intended for chronopharmacotherapy. Floating pulsatile concept was applied to increase the gastric residence of the dosage form having lag phase followed by a burst release. To overcome limitations of various approaches for imparting buoyancy, hollow/porous beads were prepared by simple process of acid-base reaction during ionotropic cross-linking using low methoxy pectin, xanthan gum, sodium carboxy methyl cellulose, guar gum, locust bean, gellan gum and calcium chloride as a cross-linking agent. Based on the preliminary studies optimized polymers were selected for formulation design with different polymers ratio concentrations. The obtained floating beads were studied for entrapment efficiency, buoyancy study, swelling index, surface morphology, in vitro release, stability studies and in vivo floating study. The floating beads obtained were porous, float up to 12-24 h. The radiological studies (X-rays) pointed out the capability of the system to release drug in lower parts of GIT after a programmed lag time for hypertension. The floating beads provided expected two-phase release pattern with initial lag time during floating in acidic medium followed by rapid pulse release in phosphate buffer. From the accelerated stability studies, it was observed that the formulations are quite stable. All formulations followed first-order release kinetics by diffusion mechanism. This approach suggested the use of hollow calcium pectinate microparticles as promising floating pulsatile drug delivery system for site- and time-specific release of drugs acting as per chronotherapy of diseases. PMID:24744159

  5. Does size and buoyancy affect the long-distance transport of floating debris?

    NASA Astrophysics Data System (ADS)

    Ryan, Peter G.

    2015-08-01

    Floating persistent debris, primarily made from plastic, disperses long distances from source areas and accumulates in oceanic gyres. However, biofouling can increase the density of debris items to the point where they sink. Buoyancy is related to item volume, whereas fouling is related to surface area, so small items (which have high surface area to volume ratios) should start to sink sooner than large items. Empirical observations off South Africa support this prediction: moving offshore from coastal source areas there is an increase in the size of floating debris, an increase in the proportion of highly buoyant items (e.g. sealed bottles, floats and foamed plastics), and a decrease in the proportion of thin items such as plastic bags and flexible packaging which have high surface area to volume ratios. Size-specific sedimentation rates may be one reason for the apparent paucity of small plastic items floating in the world’s oceans.

  6. Floating liquid bridge charge dynamics

    NASA Astrophysics Data System (ADS)

    Teschke, Omar; Soares, David Mendez; Gomes, Whyllerson Evaristo; Valente Filho, Juracyr Ferraz

    2016-01-01

    The interaction of liquid with electric fields is investigated in a configuration where up to 13 kV are applied between electrodes resulting in a 106 V/m electric field in the capillaries and where there is the formation of a free-standing fluid bridge in the interelectrode gap. The Mott-Gurney equation was fitted to the measured ionization current vs applied voltage curve which indicates that the ionization rate at the high-voltage anode electrode dimethylsulfoxide (DMSO) interface and space charging in the interelectrode gap determine the floating liquid bridge current for a given cathode-to-anode voltage. Space charge effects were measured in the cathode becker and also at the liquid bridge since the ionized charges at the anode migrate to the bridge outer surface and decrease the interfacial tension from 43 mJ/m2 to 29 mJ/m2. Two distinct structural regions then form the bridge, a charged plastic (bulk modulus ˜100 MPa) conducting outer layer with a surface conductivity of ˜10-9 Ω-1, which shapes and supports the floating fluid structure, and an inner liquid cylinder, where DMSO molecules flow.

  7. Future float zone development in industry

    NASA Technical Reports Server (NTRS)

    Sandfort, R. M.

    1980-01-01

    The present industrial requirements for float zone silicon are summarized. Developments desired by the industry in the future are reported. The five most significant problems faced today by the float zone crystal growth method in industry are discussed. They are economic, large diameter, resistivity uniformity, control of carbon, and swirl defects.

  8. 32 CFR 935.165 - Floating objects.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Floating objects. 935.165 Section 935.165 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE TERRITORIAL AND INSULAR REGULATIONS WAKE ISLAND CODE Public Safety § 935.165 Floating objects. No person may anchor, moor, or...

  9. Whatever Floats Your Boat: A Design Challenge

    ERIC Educational Resources Information Center

    Kornoelje, Joanne; Roman, Harry T.

    2012-01-01

    This article presents a simple design challenge, based on the PBS program "Design Squad's" "Watercraft" activity that will prove engaging to most technology and engineering students. In this floating boat challenge, students are to build a boat that can float and support 25 pennies for at least 10 seconds--without leaking, sinking, or tipping…

  10. 32 CFR 935.165 - Floating objects.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 6 2014-07-01 2014-07-01 false Floating objects. 935.165 Section 935.165 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE TERRITORIAL AND INSULAR REGULATIONS WAKE ISLAND CODE Public Safety § 935.165 Floating objects. No person may anchor, moor, or...

  11. 32 CFR 935.165 - Floating objects.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 6 2012-07-01 2012-07-01 false Floating objects. 935.165 Section 935.165 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE TERRITORIAL AND INSULAR REGULATIONS WAKE ISLAND CODE Public Safety § 935.165 Floating objects. No person may anchor, moor, or...

  12. 32 CFR 935.165 - Floating objects.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 6 2011-07-01 2011-07-01 false Floating objects. 935.165 Section 935.165 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE TERRITORIAL AND INSULAR REGULATIONS WAKE ISLAND CODE Public Safety § 935.165 Floating objects. No person may anchor, moor, or...

  13. 32 CFR 935.165 - Floating objects.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 6 2013-07-01 2013-07-01 false Floating objects. 935.165 Section 935.165 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE TERRITORIAL AND INSULAR REGULATIONS WAKE ISLAND CODE Public Safety § 935.165 Floating objects. No person may anchor, moor, or...

  14. Vertical pump with free floating check valve

    DOEpatents

    Lindsay, Malcolm

    1980-01-01

    A vertical pump with a bottom discharge having a free floating check valve isposed in the outlet plenum thereof. The free floating check valve comprises a spherical member with a hemispherical cage-like member attached thereto which is capable of allowing forward or reverse flow under appropriate conditions while preventing reverse flow under inappropriate conditions.

  15. Floating plant dominance as a stable state

    PubMed Central

    Scheffer, Marten; Szabó, Sándor; Gragnani, Alessandra; van Nes, Egbert H.; Rinaldi, Sergio; Kautsky, Nils; Norberg, Jon; Roijackers, Rudi M. M.; Franken, Rob J. M.

    2003-01-01

    Invasion by mats of free-floating plants is among the most important threats to the functioning and biodiversity of freshwater ecosystems ranging from temperate ponds and ditches to tropical lakes. Dark, anoxic conditions under thick floating-plant cover leave little opportunity for animal or plant life, and they can have large negative impacts on fisheries and navigation in tropical lakes. Here, we demonstrate that floating-plant dominance can be a self-stabilizing ecosystem state, which may explain its notorious persistence in many situations. Our results, based on experiments, field data, and models, represent evidence for alternative domains of attraction in ecosystems. An implication of our findings is that nutrient enrichment reduces the resilience of freshwater systems against a shift to floating-plant dominance. On the other hand, our results also suggest that a single drastic harvest of floating plants can induce a permanent shift to an alternative state dominated by rooted, submerged growth forms. PMID:12634429

  16. Real time simulator with Ti floating point digital signal processor

    SciTech Connect

    Razazian, K.; Bobis, J.P.; Dieckman, S.L.; Raptis, A.C.

    1994-08-01

    This paper describes the design and operation of a Real Time Simulator using Texas Instruments TMS320C30 digital signal processor. This system operates with two banks of memory which provide the input data to digital signal processor chip. This feature enables the TMS320C30 to be utilized in variety of applications for which external connections to acquire input data is not needed. In addition, some practical applications of this Real Time Simulator are discussed.

  17. Semi-submersible floating structure

    SciTech Connect

    Finsterwalder, K.

    1981-06-23

    A semi-submersible floating structure includes a horizontal platform with a symmetrical arrangement of buoyant bodies extending vertically downwardly from the platform. The buoyant bodies consist of a tubular column secured by a bending-resistant connection to the platform with a closed container secured to and extending downwardly from the lower end of the tubular column. The horizontal cross-sectional area of the closed container is for most of its vertical height greater than the transverse cross -sectional area of the tubular column. At least the lower portion of the closed container has a curvilinear surface. An annular wall extends around and is spaced radially outwardly from each of the closed containers and the wall, in combination with the enclosed container, forms an annular chamber therebetween open at the bottom and closed at the top. The platform and the buoyant bodies are formed of reinforced concrete or prestressed concrete.

  18. Design and optimization of floating drug delivery system of acyclovir.

    PubMed

    Kharia, A A; Hiremath, S N; Singhai, A K; Omray, L K; Jain, S K

    2010-09-01

    The purpose of the present work was to design and optimize floating drug delivery systems of acyclovir using psyllium husk and hydroxypropylmethylcellulose K4M as the polymers and sodium bicarbonate as a gas generating agent. The tablets were prepared by wet granulation method. A 3(2) full factorial design was used for optimization of drug release profile. The amount of psyllium husk (X1) and hydroxypropylmethylcellulose K4M (X2) were selected as independent variables. The times required for 50% (t(50%)) and 70% (t(70%)) drug dissolution were selected as dependent variables. All the designed nine batches of formulations were evaluated for hardness, friability, weight variation, drug content uniformity, swelling index, in vitro buoyancy, and in vitro drug release profile. All formulations had floating lag time below 3 min and constantly floated on dissolution medium for more than 24 h. Validity of the developed polynomial equation was verified by designing two check point formulations (C1 and C2). The closeness of predicted and observed values for t(50%) and t(70%) indicates validity of derived equations for the dependent variables. These studies indicated that the proper balance between psyllium husk and hydroxypropylmethylcellulose K4M can produce a drug dissolution profile similar to the predicted dissolution profile. The optimized formulations followed Higuchi's kinetics while the drug release mechanism was found to be anomalous type, controlled by diffusion through the swollen matrix. PMID:21694992

  19. Characteristics of a Single Float Seaplane During Take-off

    NASA Technical Reports Server (NTRS)

    Crowley, J W , Jr; Ronan, K M

    1925-01-01

    At the request of the Bureau of Aeronautics, Navy Department, the National Advisory Committee for Aeronautics at Langley Field is investigating the get-away characteristics of an N-9H, a DT-2, and an F-5l, as representing, respectively, a single float, a double float, and a boat type of seaplane. This report covers the investigation conducted on the N-9H. The results show that a single float seaplane trims aft in taking off. Until a planing condition is reached the angle of attack is about 15 degrees and is only slightly affected by controls. When planing it seeks a lower angle, but is controllable through a widening range, until at the take-off it is possible to obtain angles of 8 degrees to 15 degrees with corresponding speeds of 53 to 41 M. P. H. or about 40 per cent of the speed range. The point of greatest resistance occurs at about the highest angle of a pontoon planing angle of 9 1/2 degrees and at a water speed of 24 M. P. H.

  20. Three-dimensional floating images as overt security features

    NASA Astrophysics Data System (ADS)

    Dunn, Douglas S.; Potts, Travis L.; Lorimor, Lynn E.; Jonza, James M.; Smithson, Robert M.; Maki, Stephen P.

    2006-02-01

    3M has developed a proprietary laser process for creating three-dimensional images that appear to float above and/or below the plane of a substrate containing an array of microlenses. During the imaging process the laser records a microscopic image of the desired three-dimensional pattern in the material located at the focal point of each microlens in the array. The images exhibit motion parallax comparable to that seen from holograms and are easily visible in a wide range of ambient lighting conditions. The images are therefore similar, but not identical, to integral images, first proposed in 1908 by Lippmann. The fidelity of these floating images requires maintaining exact registration between the microlens array and the corresponding microimage array. In addition, the use of an ablative laser process for the production of the microimages enables the production of microimage features smaller than the diffraction limit (up to approximately 50,000 dpi). The images are therefore very difficult to simulate, counterfeit, or modify and are highly desirable as an overt security feature. 3M has scaled up the floating image process to produce images in Confirm TM Retroreflective Security Laminate to authenticate passports and driver's licenses and in retroreflective license plate sheeting as the Ensure TM Virtual Security Thread to authenticate vehicle registration. This allows addition of features to a secure document that are easily verifiable, using only the human eye, by a large and widely disperse population to create an identity document that is easily identified as genuine.

  1. Floating electron states in covalent semiconductors.

    PubMed

    Matsushita, Yu-ichiro; Furuya, Shinnosuke; Oshiyama, Atsushi

    2012-06-15

    We report first-principles electronic-structure calculations that clarify the floating nature of electron states in covalent semiconductors. It is found that wave functions of several conduction- and valence-band states, including the conduction-band minima, do not distribute near atomic sites, as was taken for granted, but float in interstitial channels in most semiconductors. The directions and shapes of the interstitial channels depend on the crystal symmetry so that mysterious variation of the energy gaps in SiC polymorphs is naturally explained by considering the floating nature. PMID:23004300

  2. Floating-gated memory based on carbon nanotube field-effect transistors with Si floating dots

    NASA Astrophysics Data System (ADS)

    Seike, Kohei; Fujii, Yusuke; Ohno, Yasuhide; Maehashi, Kenzo; Inoue, Koichi; Matsumoto, Kazuhiko

    2014-01-01

    We have fabricated a carbon nanotube field-effect transistor (CNTFET)-based nonvolatile memory device with Si floating dots. The electrical characteristics of this memory device were compared with those of devices with a HfO2 charge storage layer or Au floating dots. For a sweep width of 6 V, the memory window of the devices with the Si floating dots increased twofold as compared with that of the devices with the HfO2 layer. Moreover, the retention characteristics revealed that, for the device with the Au floating dots, the off-state had almost the same current as the on-state at the 400th s. However, the devices with the Si floating dots had longer-retention characteristics. The results indicate that CNTFET-based devices with Si floating dots are promising candidates for low-power consumption nonvolatile memory devices.

  3. 14 CFR 29.757 - Hull and auxiliary float strength.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Hull and auxiliary float strength. 29.757... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 29.757 Hull and auxiliary float strength. The hull, and auxiliary floats if used, must withstand...

  4. 14 CFR 29.757 - Hull and auxiliary float strength.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hull and auxiliary float strength. 29.757... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 29.757 Hull and auxiliary float strength. The hull, and auxiliary floats if used, must withstand...

  5. 14 CFR 29.757 - Hull and auxiliary float strength.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Hull and auxiliary float strength. 29.757... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 29.757 Hull and auxiliary float strength. The hull, and auxiliary floats if used, must withstand...

  6. 14 CFR 29.757 - Hull and auxiliary float strength.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Hull and auxiliary float strength. 29.757... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 29.757 Hull and auxiliary float strength. The hull, and auxiliary floats if used, must withstand...

  7. 14 CFR 29.757 - Hull and auxiliary float strength.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Hull and auxiliary float strength. 29.757... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 29.757 Hull and auxiliary float strength. The hull, and auxiliary floats if used, must withstand...

  8. 14 CFR 23.753 - Main float design.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Main float design. 23.753 Section 23.753... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Floats and Hulls § 23.753 Main float design. Each seaplane main float must meet the requirements of § 23.521....

  9. 14 CFR 27.751 - Main float buoyancy.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Main float buoyancy. 27.751 Section 27.751 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 27.751 Main float buoyancy. (a) For main floats, the...

  10. 14 CFR 29.751 - Main float buoyancy.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Main float buoyancy. 29.751 Section 29.751 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 29.751 Main float buoyancy. (a) For main floats,...

  11. 14 CFR 25.751 - Main float buoyancy.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Main float buoyancy. 25.751 Section 25.751 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Floats and Hulls § 25.751 Main float buoyancy. Each main float must have— (a)...

  12. 14 CFR 23.753 - Main float design.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Main float design. 23.753 Section 23.753... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Floats and Hulls § 23.753 Main float design. Each seaplane main float must meet the requirements of § 23.521....

  13. 33 CFR 144.01-1 - Life floats.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Life floats. 144.01-1 Section 144... CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-1 Life floats. Each manned platform shall be provided with at least two approved life floats. The life floats shall have...

  14. 33 CFR 144.01-1 - Life floats.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Life floats. 144.01-1 Section 144... CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-1 Life floats. Each manned platform shall be provided with at least two approved life floats. The life floats shall have...

  15. 33 CFR 144.01-1 - Life floats.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Life floats. 144.01-1 Section 144... CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-1 Life floats. Each manned platform shall be provided with at least two approved life floats. The life floats shall have...

  16. 33 CFR 144.01-1 - Life floats.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Life floats. 144.01-1 Section 144... CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-1 Life floats. Each manned platform shall be provided with at least two approved life floats. The life floats shall have...

  17. Surface tension supported floating of heavy objects: Why elongated bodies float better?

    PubMed

    Bormashenko, Edward

    2016-02-01

    Floating of bodies heavier than the supporting liquid is discussed. Floating of cylindrical, ellipsoidal bodies and rectangular plates possessing lateral dimensions smaller than the capillary length is treated. It is demonstrated that more elongated bodies of a fixed volume are better supported by capillary forces, due to the increase in the perimeter of the triple line. Thus, floating of metallic needles obtains reasonable explanation. PMID:26513731

  18. Exploring Floating Concrete and Beam Design.

    ERIC Educational Resources Information Center

    Snell, Billie G.; Snell, Luke M.

    2002-01-01

    Presents two construction activities that address both state and federal science standards and encourage students to consider career options in mathematics and science. Includes floating concrete and paper bridge activities. (YDS)

  19. Lagrangian floats as sea floor imaging platforms

    NASA Astrophysics Data System (ADS)

    Roman, Chris; Inglis, Gabrielle; McGilvray, Bryan

    2011-10-01

    There is a persistent need for high resolution photographic images of the sea floor and associated biota for marine habitat classification and fisheries stock assessment. This paper presents a novel low cost Lagrangian imaging platform that offers high quality images with reduced operational demands in comparison to existing methodologies such as diver surveys, drop cameras, ship towed systems and dedicated remote or autonomous underwater vehicles. The platform consists of a recently developed bottom following Lagrangian float fit with down looking stereo cameras and strobe lighting. The float can use active ballasting to perform constant altitude photographic drift surveys in coastal waters over varying bathymetry. Images from the float can be used to create large photomosaics, stereographic bathymetry estimates and image-derived current measurements. Test data are presented to demonstrate the operation of the Lagrangian float and summarize the data products.

  20. Archimedes' floating bodies on a spherical Earth

    NASA Astrophysics Data System (ADS)

    Rorres, Chris

    2016-01-01

    Archimedes was the first to systematically find the centers of gravity of various solid bodies and to apply this concept in determining stable configurations of floating bodies. In this paper, we discuss an error in a proof developed by Archimedes that involves determining whether a uniform, spherical cap will float stably with its base horizontal in a liquid on a spherical Earth. We present a simpler, corrected proof and discuss aspects of his proof regarding a spherical cap that is not uniform.

  1. Floating phenomenon and mode of color appearance

    NASA Astrophysics Data System (ADS)

    Aoki, Hironobu; Shinoda, Hiroyuki; Ikeda, Mitsuo

    2002-06-01

    We found an interesting phenomenon concerning the motion perception and the mode of color appearance. We suppose you are holding a stiff sheet of picture and move it laterally to and fro in front of the eye. Though the picture and all items in it move physically altogether with your hand, your perception is not always so. But when the picture that is a figure appears light-source color mode and a background of object color, a figure appears to slip on a background. We call this a 'floating phenomenon.' We predicted the occurrence of floating phenomenon depends on whether the color is perceived to belong to an object or not. To examine the relation between the floating phenomenon and the mode of color appearance, we measured the luminance threshold of floating phenomenon and the transition luminance between two color modes by constant stimulus method to use a mondrian. Our results show the floating never occurred when the target appeared as object color mode. The floating phenomenon may be caused by the separation of the light-source color from an object or week-belonging.

  2. Floating intake reduces pump damage

    SciTech Connect

    Kronig, A.

    1993-12-31

    The solution to a costly sand erosion problem at the Grande Dixence hydroelectric project in Switzerland turned out to be as simple as a floating pump. The 726-MW Grande Dixence project drains a 350-square-kilometer reach of the Zermatt and Herens valleys in the southwestern Swiss Alps. About half of the drainage area is covered by active glaciers. Because the glaciers in Zermatt Valley are so low in altitude, their water is collected in Z`mutt Reservoir at the base of the Matterhorn, then pumped up 500 meters for transport to the main Grande Disence Reservoir near Sion. The glacier water is heavily laden with sand. In spite of a gravel pass and a desilter, the 700,000-acubic-meter Z`mutt Reservoir receives large quantities of sand. The sand tends to remain in solution because of the low water temperatures (1 to 2 degrees Centigrade). In the original intake system, the sand would be sucked into the pump intakes, causing extensive erosion to the pump wheels and an expensive yearly program of repair. (Pump damage averaged 200,000 Swiss Francs ($284,000 U.S.) per year between 1980 and 1985.)

  3. Cadmium uptake by floating macrophytes.

    PubMed

    Maine, M A; Duarte, M V; Suñé, N L

    2001-08-01

    Cd uptake capacity of a group of floating macrophytes (Salvinia herzogii, Pistia stratiotes, Hydromistia stolonifera and Eichhornia crassipes) was determined in outdoors experiments during the lowest temperature period of the year. Although all studied species were highly efficient in the Cd uptake, Pistia stratiotes was selected for further research because of its superior performance and its higher average relative growth rate. Cadmium% removal by Pistia stratiotes was greater in the first 24 h of the experiments (63, 65, 72 and 74% of the added Cd for 1, 2, 4 and 6 mg Cd 1(-1), respectively). After 31 days of growth, Pistia statiotes efficiently removed Cd at the studied concentrations. The macrophyte was able to keep its capacity for Cd removal even though some toxicity symptoms appeared at 4 and 6 mg Cd 1(-1). The greater the initial concentration, the greater Cd bioaccumulation rates. The increase of Cd concentration in plant tissues occurred especially in roots and was linearly related to the quantity of Cd added. Cd sorption by roots is faster than translocation to the plant aerial part and it occurs mainly during the first 24h. PMID:11456161

  4. PREDICTIVE PHARMACOKINETICS OF TRAMADOL HYDROCHLORIDE FLOATING TABLETS.

    PubMed

    Wang, Jianming; Zhang, Yanzhen; Guo, Zhiling; Tao, Qingwen; Wang, Yongjun; Zhou, Wei; Ma, Xiao; Li, Zhihong

    2016-01-01

    The purpose of this study was to propose the effectiveness of convolution approach to predict pharmacokinetics of tramadol hydrochloride floating tablets, prepared by using various ratios of carbopol, HPMC K100M, and Hibiscus rosa Sinensis as excipient. The in vitro dissolution test was conducted using paddle method in 900 mL of HCl buffer with pH 1.2 to simulate the gastric condition. The stirring speed of paddles was set at 70 rpm. Temperature of dissolution medium was adjusted at 37 ± 5 °C. At predetermined time points, 5 mL of dissolution samples were taken with a replacement of same volume using fresh medium. The obtained samples were analyzed at 271 nm using UV visible spectrophotometer. The values of predicted pharmacokinetic parameters like Cmax (maximum blood drug level), Tmax (time required to attain maximum blood drug level), and AUC (area under blood drug concentration curve) ranged between 80.8 ± 3.2-119.6 ± 4.7 ng/mL, 11.4 ± 0.2-12.2 ± 0.2 h, and 1430.5 ± 209.5-1970.6 ± 287.4 ng.h/mL, respectively. This certainly is a desired feature required at the formulation development step, where the formulator requires the development of a formulation using desired in vivo features on the basis of only accessible in vitro data. It can be concluded from the results that convolution method is a practical method for the prediction of drug concentration in blood and for quality control. PMID:27476294

  5. Battery charging in float vs. cycling environments

    SciTech Connect

    COREY,GARTH P.

    2000-04-20

    In lead-acid battery systems, cycling systems are often managed using float management strategies. There are many differences in battery management strategies for a float environment and battery management strategies for a cycling environment. To complicate matters further, in many cycling environments, such as off-grid domestic power systems, there is usually not an available charging source capable of efficiently equalizing a lead-acid battery let alone bring it to a full state of charge. Typically, rules for battery management which have worked quite well in a floating environment have been routinely applied to cycling batteries without full appreciation of what the cycling battery really needs to reach a full state of charge and to maintain a high state of health. For example, charge target voltages for batteries that are regularly deep cycled in off-grid power sources are the same as voltages applied to stand-by systems following a discharge event. In other charging operations equalization charge requirements are frequently ignored or incorrectly applied in cycled systems which frequently leads to premature capacity loss. The cause of this serious problem: the application of float battery management strategies to cycling battery systems. This paper describes the outcomes to be expected when managing cycling batteries with float strategies and discusses the techniques and benefits for the use of cycling battery management strategies.

  6. Floating seal system for rotary devices

    DOEpatents

    Banasiuk, H.A.

    1983-08-23

    This invention relates to a floating seal system for rotary devices to reduce gas leakage around the rotary device in a duct and across the face of the rotary device to an adjacent duct. The peripheral seal bodies are made of resilient material having a generally U-shaped cross section wherein one of the legs is secured to a support member and the other of the legs forms a contacting seal against the rotary device. The legs of the peripheral seal form an extended angle of intersection of about 10[degree] to about 30[degree] in the unloaded condition to provide even sealing forces around the periphery of the rotary device. The peripheral seal extends around the periphery of the support member except where intersected by radial seals which reduce gas leakage across the face of the rotary device and between adjacent duct portions. The radial seal assembly is fabricated from channel bars, the smaller channel bar being secured to the divider of the support member and a larger inverted rigid floating channel bar having its legs freely movable over the legs of the smaller channel bar forming therewith a tubular channel. A resilient flexible tube is positioned within the tubular channel for substantially its full length to reduce gas leakage across the tubular channel. A spacer extends beyond the face of the floating channel near each end of the floating channel a distance to provide desired clearance between the floating channel and the face of the rotary device. 5 figs.

  7. Floating seal system for rotary devices

    DOEpatents

    Banasiuk, Hubert A.

    1983-01-01

    This invention relates to a floating seal system for rotary devices to reduce gas leakage around the rotary device in a duct and across the face of the rotary device to an adjacent duct. The peripheral seal bodies are made of resilient material having a generally U-shaped cross section wherein one of the legs is secured to a support member and the other of the legs forms a contacting seal against the rotary device. The legs of the peripheral seal form an extended angle of intersection of about 10.degree. to about 30.degree. in the unloaded condition to provide even sealing forces around the periphery of the rotary device. The peripheral seal extends around the periphery of the support member except where intersected by radial seals which reduce gas leakage across the face of the rotary device and between adjacent duct portions. The radial seal assembly is fabricated from channel bars, the smaller channel bar being secured to the divider of the support member and a larger inverted rigid floating channel bar having its legs freely movable over the legs of the smaller channel bar forming therewith a tubular channel. A resilient flexible tube is positioned within the tubular channel for substantially its full length to reduce gas leakage across the tubular channel. A spacer extends beyond the face of the floating channel near each end of the floating channel a distance to provide desired clearance between the floating channel and the face of the rotary device.

  8. A novel floating controlled release drug delivery system prepared by hot-melt extrusion.

    PubMed

    Vo, Anh Q; Feng, Xin; Morott, Joseph T; Pimparade, Manjeet B; Tiwari, Roshan V; Zhang, Feng; Repka, Michael A

    2016-01-01

    Floating dosage forms are an important formulation strategy for drugs with a narrow absorption window and low intestinal solubility, and for localized gastric treatment. Novel floating pellets were prepared using the hot-melt extrusion (HME) technology. Uniformly foamed strands were created by liquid injection pumping and screw configuration modification. The ammonio methacrylate copolymer (Eudragit® RSPO) foaming structure was formed by a liquid-vapor phase transition inside the strand upon die exiting resulting from the sudden decrease in external pressure, vaporizing the liquid ethanol and vacating the extruded material. This generated uniform vacuous regions in the extrudate. The pellets' internal structure was investigated using scanning electron microscopy (SEM). The formulation constituents' and processing parameters' effects on the drug release profiles, floating force, and the pellets' micromeritic properties were evaluated by design of experiments: all formulations showed zero lag time and excellent floating strength, indicating immediate-floating pellet formation. The pellets' drug release profiles were controlled by multiple independent variables at different time points (⩽ 24 h). Drug loading significantly affected drug release within the first hour, the hydroxypropyl methylcellulose (HPMC) content thereafter. Understanding the variables' effects on the formulations allows for the tailoring of this delivery system to obtain various drug release profiles. PMID:26643801

  9. Floating zone melting of cadmium telluride

    NASA Technical Reports Server (NTRS)

    Chang, Wen-Ming; Regel, L. L.; Wilcox, W. R.

    1992-01-01

    To produce superior crystals of cadmium telluride, floating zone melting in space has been proposed. Techniques required for floating zone melting of cadmium telluride are being developed. We have successfully float-zoned cadmium telluride on earth using square rods. A resistance heater was constructed for forming the molten zone. Evaporation of the molten zone was controlled by adding excess cadmium to the growth ampoule combined with heating of the entire ampoule. An effective method to hold the feed rod was developed. Slow rotation of the growth ampoule was proven experimentally to be necessary to achieve a complete symmetric molten zone. Most of the resultant cylindrical rods were single crystals with twins. Still needed is a suitable automatic method to control the zone length. We tried a fiber optical technique to control the zone length, but experiments showed that application of this technique to automate zone length control is unlikely to be successful.

  10. Floating mechanism of a small liquid marble

    NASA Astrophysics Data System (ADS)

    Ooi, Chin Hong; Plackowski, Chris; Nguyen, Anh V.; Vadivelu, Raja K.; John, James A. St.; Dao, Dzung Viet; Nguyen, Nam-Trung

    2016-02-01

    Flotation of small solid objects and liquid droplets on water is critical to natural and industrial activities. This paper reports the floating mechanism of liquid marbles, or liquid droplets coated with hydrophobic microparticles. We used X-ray computed tomography (XCT) to acquire cross-sectional images of the floating liquid marble and interface between the different phases. We then analysed the shape of the liquid marble and the angles at the three-phase contact line (TPCL). We found that the small floating liquid marbles follow the mechanism governing the flotation of solid objects in terms of surface tension forces. However, the contact angles formed and deformation of the liquid marble resemble that of a sessile liquid droplet on a thin, elastic solid. For small liquid marbles, the contact angle varies with volume due to the deformability of the interface.

  11. Vibration characteristics of floating slab track

    NASA Astrophysics Data System (ADS)

    Kuo, Chen-Ming; Huang, Cheng-Hao; Chen, Yi-Yi

    2008-11-01

    Coupled equilibrium equations of suspended wheels and floating slab track system were solved with the fourth-order Runge-Kutta method to obtain the deflections, vibration velocities, and wheel-rail contact forces. The program was validated through several aspects. Cases with various vehicle speed, slab mass, and stiffness of slab bearing were analyzed to reveal the effects of slab bearing on track responses. The correlation between wheel-rail resonance and train speed was also discussed. It was found that rail deflections increase significantly as train speed increases. Although large slab mass may lower tuning frequency, it could also result in higher wheel-rail contact force and rail deflections. The floating slab track is effective in isolating loading above 10 Hz, which might present in some railway sections with irregularities. Adopting floating slab track for vibration control for environment along the railway may cause concerns about ride quality and track damages.

  12. Floating mechanism of a small liquid marble

    PubMed Central

    Ooi, Chin Hong; Plackowski, Chris; Nguyen, Anh V.; Vadivelu, Raja K.; John, James A. St.; Dao, Dzung Viet; Nguyen, Nam-Trung

    2016-01-01

    Flotation of small solid objects and liquid droplets on water is critical to natural and industrial activities. This paper reports the floating mechanism of liquid marbles, or liquid droplets coated with hydrophobic microparticles. We used X-ray computed tomography (XCT) to acquire cross-sectional images of the floating liquid marble and interface between the different phases. We then analysed the shape of the liquid marble and the angles at the three-phase contact line (TPCL). We found that the small floating liquid marbles follow the mechanism governing the flotation of solid objects in terms of surface tension forces. However, the contact angles formed and deformation of the liquid marble resemble that of a sessile liquid droplet on a thin, elastic solid. For small liquid marbles, the contact angle varies with volume due to the deformability of the interface. PMID:26902930

  13. Floating mechanism of a small liquid marble.

    PubMed

    Ooi, Chin Hong; Plackowski, Chris; Nguyen, Anh V; Vadivelu, Raja K; John, James A St; Dao, Dzung Viet; Nguyen, Nam-Trung

    2016-01-01

    Flotation of small solid objects and liquid droplets on water is critical to natural and industrial activities. This paper reports the floating mechanism of liquid marbles, or liquid droplets coated with hydrophobic microparticles. We used X-ray computed tomography (XCT) to acquire cross-sectional images of the floating liquid marble and interface between the different phases. We then analysed the shape of the liquid marble and the angles at the three-phase contact line (TPCL). We found that the small floating liquid marbles follow the mechanism governing the flotation of solid objects in terms of surface tension forces. However, the contact angles formed and deformation of the liquid marble resemble that of a sessile liquid droplet on a thin, elastic solid. For small liquid marbles, the contact angle varies with volume due to the deformability of the interface. PMID:26902930

  14. Development of hybrid fluid jet/float polishing process

    NASA Astrophysics Data System (ADS)

    Beaucamp, Anthony T. H.; Namba, Yoshiharu; Freeman, Richard R.

    2013-09-01

    On one hand, the "float polishing" process consists of a tin lap having many concentric grooves, cut from a flat by single point diamond turning. This lap is rotated above a hydrostatic bearing spindle of high rigidity, damping and rotational accuracy. The optical surface thus floats above a thin layer of abrasive particles. But whilst surface texture can be smoothed to ~0.1nm rms (as measured by atomic force microscopy), this process can only be used on flat surfaces. On the other hand, the CNC "fluid jet polishing" process consists of pumping a mixture of water and abrasive particles to a converging nozzle, thus generating a polishing spot that can be moved along a tool path with tight track spacing. But whilst tool path feed can be moderated to ultra-precisely correct form error on freeform optical surfaces, surface finish improvement is generally limited to ~1.5nm rms (with fine abrasives). This paper reports on the development of a novel finishing method, that combines the advantages of "fluid jet polishing" (i.e. freeform corrective capability) with "float polishing" (i.e. super-smooth surface finish of 0.1nm rms or less). To come up with this new "hybrid" method, computational fluid dynamic modeling of both processes in COMSOL is being used to characterize abrasion conditions and adapt the process parameters of experimental fluid jet polishing equipment, including: (1) geometrical shape of nozzle, (2) position relative to the surface, (3) control of inlet pressure. This new process is aimed at finishing of next generation X-Ray / Gamma Ray focusing optics.

  15. On the Assimilation of Argo Float Trajectories into the Mediterranean Forecasting System

    NASA Astrophysics Data System (ADS)

    Nilsson, Jenny A. U.; Dobricic, Srdjan; Taillandier, Vincent; Poulain, Pierre-Marie; Pinardi, Nadia

    2010-05-01

    availability of Argo-float data was noted during the period, with the maximum amount and spread of floats in 2005. The impact of the fall-off in float abundance was studied in terms of analyses, and implications on the operational activities will be pointed out.

  16. Hiding and feeding in floating seaweed: Floating seaweed clumps as possible refuges or feeding grounds for fishes

    NASA Astrophysics Data System (ADS)

    Vandendriessche, Sofie; Messiaen, Marlies; O'Flynn, Sarah; Vincx, Magda; Degraer, Steven

    2007-02-01

    Floating seaweed is considered to be an important habitat for juvenile fishes due to the provision of food, shelter, a visual orientation point and passive transport. The importance of the presence of the highly dynamical seaweed clumps from the North Sea to juvenile neustonic fishes was investigated by analysing both neuston samples (without seaweed) and seaweed samples concerning fish community structure, and length-frequency distributions and feeding habits of five associated fish species. While the neustonic fish community was mainly seasonally structured, the seaweed-associated fish community was more complex: the response of the associated fish species to environmental variables was species specific and probably influenced by species interactions, resulting in a large multivariate distance between the samples dominated by Chelon labrosus and the samples dominated by Cyclopterus lumpus, Trachurus trachurus and Ciliata mustela. The results of the stomach analysis confirmed that C. lumpus is a weedpatch specialist that has a close spatial affinity with the seaweed and feeds intensively on the seaweed-associated invertebrate fauna. Similarly, C. mustela juveniles also fed on the seaweed fauna, but in a more opportunistic way. The shape of the size-frequency distribution suggested enhanced growth when associated with floating seaweed. Chelon labrosus and T. trachurus juveniles were generally large in seaweed samples, but large individuals were also encountered in the neuston. The proportion of associated invertebrate fauna in their diet was of minor importance, compared to the proportions in C. lumpus. Individuals of Syngnathus rostellatus mainly fed on planktonic invertebrates but had a discontinuous size-frequency distribution, suggesting that some of the syngnathids were carried with the seaweed upon detachment and stayed associated. Floating seaweeds can therefore be regarded as ephemeral habitats shared between several fish species (mainly juveniles) that use

  17. 33 CFR 144.01-15 - Alternates for life floats.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Alternates for life floats. 144... for life floats. (a) Approved lifeboats, approved life rafts or approved inflatable life rafts may be used in lieu of approved life floats for either all or part of the capacity required. When...

  18. 33 CFR 144.01-15 - Alternates for life floats.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Alternates for life floats. 144... for life floats. (a) Approved lifeboats, approved life rafts or approved inflatable life rafts may be used in lieu of approved life floats for either all or part of the capacity required. When...

  19. 33 CFR 144.01-15 - Alternates for life floats.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Alternates for life floats. 144... for life floats. (a) Approved lifeboats, approved life rafts or approved inflatable life rafts may be used in lieu of approved life floats for either all or part of the capacity required. When...

  20. 33 CFR 144.01-15 - Alternates for life floats.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Alternates for life floats. 144... for life floats. (a) Approved lifeboats, approved life rafts or approved inflatable life rafts may be used in lieu of approved life floats for either all or part of the capacity required. When...

  1. 14 CFR 25.753 - Main float design.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Main float design. 25.753 Section 25.753 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Floats and Hulls § 25.753 Main float...

  2. 14 CFR 25.753 - Main float design.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Main float design. 25.753 Section 25.753 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Floats and Hulls § 25.753 Main float...

  3. 14 CFR 25.535 - Auxiliary float loads.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... follows: EC28SE91.043 where— ρ=mass density of water (slugs/ft.2); V=volume of float (ft.2); C x... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Water Loads § 25.535 Auxiliary float loads. (a..., the prescribed water loads may be distributed over the float bottom to avoid excessive local...

  4. 14 CFR 25.535 - Auxiliary float loads.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... follows: EC28SE91.043 where— ρ=mass density of water (slugs/ft.2); V=volume of float (ft.2); C x... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Water Loads § 25.535 Auxiliary float loads. (a..., the prescribed water loads may be distributed over the float bottom to avoid excessive local...

  5. 14 CFR 25.535 - Auxiliary float loads.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... follows: EC28SE91.043 where— ρ=mass density of water (slugs/ft.2); V=volume of float (ft.2); C x... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Water Loads § 25.535 Auxiliary float loads. (a..., the prescribed water loads may be distributed over the float bottom to avoid excessive local...

  6. 14 CFR 25.535 - Auxiliary float loads.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... follows: EC28SE91.043 where— ρ=mass density of water (slugs/ft.2); V=volume of float (ft.2); C x... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Water Loads § 25.535 Auxiliary float loads. (a..., the prescribed water loads may be distributed over the float bottom to avoid excessive local...

  7. 14 CFR 25.535 - Auxiliary float loads.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... follows: EC28SE91.043 where— ρ=mass density of water (slugs/ft.2); V=volume of float (ft.2); C x... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Water Loads § 25.535 Auxiliary float loads. (a..., the prescribed water loads may be distributed over the float bottom to avoid excessive local...

  8. 46 CFR 131.870 - Life floats and buoyant apparatus.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Life floats and buoyant apparatus. 131.870 Section 131... OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.870 Life floats and buoyant apparatus. (a) The name of the vessel must be plainly marked or painted on each life float or buoyant...

  9. 46 CFR 131.870 - Life floats and buoyant apparatus.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Life floats and buoyant apparatus. 131.870 Section 131... OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.870 Life floats and buoyant apparatus. (a) The name of the vessel must be plainly marked or painted on each life float or buoyant...

  10. 46 CFR 131.870 - Life floats and buoyant apparatus.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Life floats and buoyant apparatus. 131.870 Section 131... OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.870 Life floats and buoyant apparatus. (a) The name of the vessel must be plainly marked or painted on each life float or buoyant...

  11. 46 CFR 131.870 - Life floats and buoyant apparatus.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.870 Life floats and buoyant apparatus. (a) The name of the vessel must be plainly marked or painted on each life float or buoyant apparatus... 46 Shipping 4 2010-10-01 2010-10-01 false Life floats and buoyant apparatus. 131.870 Section...

  12. 46 CFR 131.870 - Life floats and buoyant apparatus.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.870 Life floats and buoyant apparatus. (a) The name of the vessel must be plainly marked or painted on each life float or buoyant apparatus... 46 Shipping 4 2011-10-01 2011-10-01 false Life floats and buoyant apparatus. 131.870 Section...

  13. Floating--A Key to Survival.

    ERIC Educational Resources Information Center

    Anderson, Norman

    1980-01-01

    Described are several activities to be used to help students grasp the concept of floating. The activities include the use of a spring scale to measure the weight of the objects in air, in water, and in salt water, and a discussion of why there are differences in these weights. (DS)

  14. Subtropical Productivity from Profiling Floats and Gliders

    NASA Astrophysics Data System (ADS)

    Nicholson, D. P.; Johnson, K. S.; Karl, D. M.

    2015-12-01

    Since 2007 profiling floats equipped with dissolved oxygen and nitrate sensors have been released from the Hawaii Ocean Time-series (HOT) and Bermuda Atlantic Time-series Study (BATS) sites and can be calibrated using time-series observations. More recent deployments have also included bio-optical and pH sensors. Gliders with oxygen sensors and bio-optics have been intermittently deployed near HOT Station ALOHA since 2008 and at BATS since 2014. While gliders maintain a restricted survey region near the time-series stations, profiling floats drifted widely across the subtropical gyres. Multiple floats and gliders enables a cotemporaneous comparison of biogeochemical processes across gyres. These platforms enable observations on spatial scales from submesoscale to basin scale and on temporal scales from diel to interannual. Here, I focus on the spatiotemporal variability of nitrate and oxygen mass balances in the North Pacific and North Atlantic subtropical gyres using a data-assimilating and float-tracking 1D upper ocean model.

  15. Genetics Home Reference: Floating-Harbor syndrome

    MedlinePlus

    ... Arpin S, Afenjar A, Dubern B, Toutain A, Cabrol S, Héron D. Floating-Harbor Syndrome: report on a case ... G, Whiteford ML, Quaio CR, Gomy I, Bertola DR, Albrecht B, Platzer K, McGillivray G, Zou R, ...

  16. Dealing with Human Death: The Floating Perspective.

    ERIC Educational Resources Information Center

    Kenyon, Gary M.

    1991-01-01

    Explores approach to dealing with human death. Describes floating perspective, based on insights from Choron and Jaspers, as suggesting it is possible to deal with human death by refraining from taking ultimate position on the problem. Position encourages openness to death. Examines role of anxiety and describes possible meaningful outcomes of…

  17. Design of crossed-mirror array to form floating 3D LED signs

    NASA Astrophysics Data System (ADS)

    Yamamoto, Hirotsugu; Bando, Hiroki; Kujime, Ryousuke; Suyama, Shiro

    2012-03-01

    3D representation of digital signage improves its significance and rapid notification of important points. Our goal is to realize floating 3D LED signs. The problem is there is no sufficient device to form floating 3D images from LEDs. LED lamp size is around 1 cm including wiring and substrates. Such large pitch increases display size and sometimes spoils image quality. The purpose of this paper is to develop optical device to meet the three requirements and to demonstrate floating 3D arrays of LEDs. We analytically investigate image formation by a crossed mirror structure with aerial aperture, called CMA (crossed-mirror array). CMA contains dihedral corner reflectors at each aperture. After double reflection, light rays emitted from an LED will converge into the corresponding image point. We have fabricated CMA for 3D array of LEDs. One CMA unit contains 20 x 20 apertures that are located diagonally. Floating image of LEDs was formed in wide range of incident angle. The image size of focused beam agreed to the apparent aperture size. When LEDs were located three-dimensionally (LEDs in three depths), the focused distances were the same as the distance between the real LED and the CMA.

  18. Real object-based 360-degree integral-floating display using multiple depth camera

    NASA Astrophysics Data System (ADS)

    Erdenebat, Munkh-Uchral; Dashdavaa, Erkhembaatar; Kwon, Ki-Chul; Wu, Hui-Ying; Yoo, Kwan-Hee; Kim, Young-Seok; Kim, Nam

    2015-03-01

    A novel 360-degree integral-floating display based on the real object is proposed. The general procedure of the display system is similar with conventional 360-degree integral-floating displays. Unlike previously presented 360-degree displays, the proposed system displays the 3D image generated from the real object in 360-degree viewing zone. In order to display real object in 360-degree viewing zone, multiple depth camera have been utilized to acquire the depth information around the object. Then, the 3D point cloud representations of the real object are reconstructed according to the acquired depth information. By using a special point cloud registration method, the multiple virtual 3D point cloud representations captured by each depth camera are combined as single synthetic 3D point cloud model, and the elemental image arrays are generated for the newly synthesized 3D point cloud model from the given anamorphic optic system's angular step. The theory has been verified experimentally, and it shows that the proposed 360-degree integral-floating display can be an excellent way to display real object in the 360-degree viewing zone.

  19. Unsteady aerodynamic analysis for offshore floating wind turbines under different wind conditions.

    PubMed

    Xu, B F; Wang, T G; Yuan, Y; Cao, J F

    2015-02-28

    A free-vortex wake (FVW) model is developed in this paper to analyse the unsteady aerodynamic performance of offshore floating wind turbines. A time-marching algorithm of third-order accuracy is applied in the FVW model. Owing to the complex floating platform motions, the blade inflow conditions and the positions of initial points of vortex filaments, which are different from the fixed wind turbine, are modified in the implemented model. A three-dimensional rotational effect model and a dynamic stall model are coupled into the FVW model to improve the aerodynamic performance prediction in the unsteady conditions. The effects of floating platform motions in the simulation model are validated by comparison between calculation and experiment for a small-scale rigid test wind turbine coupled with a floating tension leg platform (TLP). The dynamic inflow effect carried by the FVW method itself is confirmed and the results agree well with the experimental data of a pitching transient on another test turbine. Also, the flapping moment at the blade root in yaw on the same test turbine is calculated and compares well with the experimental data. Then, the aerodynamic performance is simulated in a yawed condition of steady wind and in an unyawed condition of turbulent wind, respectively, for a large-scale wind turbine coupled with the floating TLP motions, demonstrating obvious differences in rotor performance and blade loading from the fixed wind turbine. The non-dimensional magnitudes of loading changes due to the floating platform motions decrease from the blade root to the blade tip. PMID:25583859

  20. Unsteady aerodynamic analysis for offshore floating wind turbines under different wind conditions

    PubMed Central

    Xu, B. F.; Wang, T. G.; Yuan, Y.; Cao, J. F.

    2015-01-01

    A free-vortex wake (FVW) model is developed in this paper to analyse the unsteady aerodynamic performance of offshore floating wind turbines. A time-marching algorithm of third-order accuracy is applied in the FVW model. Owing to the complex floating platform motions, the blade inflow conditions and the positions of initial points of vortex filaments, which are different from the fixed wind turbine, are modified in the implemented model. A three-dimensional rotational effect model and a dynamic stall model are coupled into the FVW model to improve the aerodynamic performance prediction in the unsteady conditions. The effects of floating platform motions in the simulation model are validated by comparison between calculation and experiment for a small-scale rigid test wind turbine coupled with a floating tension leg platform (TLP). The dynamic inflow effect carried by the FVW method itself is confirmed and the results agree well with the experimental data of a pitching transient on another test turbine. Also, the flapping moment at the blade root in yaw on the same test turbine is calculated and compares well with the experimental data. Then, the aerodynamic performance is simulated in a yawed condition of steady wind and in an unyawed condition of turbulent wind, respectively, for a large-scale wind turbine coupled with the floating TLP motions, demonstrating obvious differences in rotor performance and blade loading from the fixed wind turbine. The non-dimensional magnitudes of loading changes due to the floating platform motions decrease from the blade root to the blade tip. PMID:25583859

  1. Using Tensor Completion Method to Achieving Better Coverage of Traffic State Estimation from Sparse Floating Car Data

    PubMed Central

    Ran, Bin; Song, Li; Cheng, Yang; Tan, Huachun

    2016-01-01

    Traffic state estimation from the floating car system is a challenging problem. The low penetration rate and random distribution make available floating car samples usually cover part space and time points of the road networks. To obtain a wide range of traffic state from the floating car system, many methods have been proposed to estimate the traffic state for the uncovered links. However, these methods cannot provide traffic state of the entire road networks. In this paper, the traffic state estimation is transformed to solve a missing data imputation problem, and the tensor completion framework is proposed to estimate missing traffic state. A tensor is constructed to model traffic state in which observed entries are directly derived from floating car system and unobserved traffic states are modeled as missing entries of constructed tensor. The constructed traffic state tensor can represent spatial and temporal correlations of traffic data and encode the multi-way properties of traffic state. The advantage of the proposed approach is that it can fully mine and utilize the multi-dimensional inherent correlations of traffic state. We tested the proposed approach on a well calibrated simulation network. Experimental results demonstrated that the proposed approach yield reliable traffic state estimation from very sparse floating car data, particularly when dealing with the floating car penetration rate is below 1%. PMID:27448326

  2. Using Tensor Completion Method to Achieving Better Coverage of Traffic State Estimation from Sparse Floating Car Data.

    PubMed

    Ran, Bin; Song, Li; Zhang, Jian; Cheng, Yang; Tan, Huachun

    2016-01-01

    Traffic state estimation from the floating car system is a challenging problem. The low penetration rate and random distribution make available floating car samples usually cover part space and time points of the road networks. To obtain a wide range of traffic state from the floating car system, many methods have been proposed to estimate the traffic state for the uncovered links. However, these methods cannot provide traffic state of the entire road networks. In this paper, the traffic state estimation is transformed to solve a missing data imputation problem, and the tensor completion framework is proposed to estimate missing traffic state. A tensor is constructed to model traffic state in which observed entries are directly derived from floating car system and unobserved traffic states are modeled as missing entries of constructed tensor. The constructed traffic state tensor can represent spatial and temporal correlations of traffic data and encode the multi-way properties of traffic state. The advantage of the proposed approach is that it can fully mine and utilize the multi-dimensional inherent correlations of traffic state. We tested the proposed approach on a well calibrated simulation network. Experimental results demonstrated that the proposed approach yield reliable traffic state estimation from very sparse floating car data, particularly when dealing with the floating car penetration rate is below 1%. PMID:27448326

  3. OCD metrology by floating n/k

    NASA Astrophysics Data System (ADS)

    Yu, Shinn-Sheng; Huang, Jacky; Ke, Chih-Ming; Gau, Tsai-Sheng; Lin, Burn J.; Yen, Anthony; Lane, Lawrence; Vuong, Vi; Chen, Yan

    2007-03-01

    In this paper, one of the major contributions to the OCD metrology error, resulting from within-wafer variation of the refractive index/extinction coefficient (n/k) of the substrate, is identified and quantified. To meet the required metrology accuracy for the 65-nm node and beyond, it is suggested that n/k should be floating when performing the regression for OCD modeling. A feasible way of performing such regression is proposed and verified. As shown in the presented example, the measured CDU (3σ) with n/k fixed and n/k floating is 1.94 nm and 1.42 nm, respectively. That is, the metrology error of CDU committed by assuming n/k fixed is more than 35% of the total CDU.

  4. Electrodynamic convection in silicon floating zones

    NASA Astrophysics Data System (ADS)

    Mühlbauer, A.; Erdmann, W.; Keller, W.

    1983-12-01

    Using a simplified Navier-Stokes equation it has been possible to compute the electrodynamic convection generated by a radio frequency coil field for the modern needle-eye float-zone growth of silicon. The calculated electrodynamic force in such a zone shows maximum values up to 11.7 N/cm 3 and generates flow velocities between 25 and 100 cm/s. As only superficial convection can be brought about by electrodynamic forces, the axial and radial dopant incorporation will not be influenced strongly. A comparison of electrodynamic forces with the other forces possibly causing flow in silicon floating zones shows that the electrodynamic forces exceed all other forces by several orders of magnitude.

  5. Sonar location system for freely floating buoys

    NASA Astrophysics Data System (ADS)

    Bird, I. G.

    1983-05-01

    A rf interrogated sonar location system for freely floating buoys is described. The location of an array of up to three buoys may be determined on an almost continuous basis within a radius of 500 m from a shipboard monitoring station. Location accuracy of typically ±0.5 m at 200-m range, low cost, and ease of operation are the major features of the system.

  6. TVFMCATS. Time Variant Floating Mean Counting Algorithm

    SciTech Connect

    Huffman, R.K.

    1999-05-01

    This software was written to test a time variant floating mean counting algorithm. The algorithm was developed by Westinghouse Savannah River Company and a provisional patent has been filed on the algorithm. The test software was developed to work with the Val Tech model IVB prototype version II count rate meter hardware. The test software was used to verify the algorithm developed by WSRC could be correctly implemented with the vendor`s hardware.

  7. Floating vs flying: A propulsion energy comparison

    NASA Technical Reports Server (NTRS)

    Marbury, F.

    1975-01-01

    Floating craft are compared to those that fly. Drag/weight for floaters is shown to be proportional to v squared/L, while for flyers it is independent of size and speed. The transportation market will therefore assign airships to lower speeds than airplanes, and will favor large airship sizes. Drag of an airship is shown to be only 11 percent of submarine drag at equal displacement and speed, raising the possibility that airships can compete with some types of ships.

  8. Time Variant Floating Mean Counting Algorithm

    Energy Science and Technology Software Center (ESTSC)

    1999-06-03

    This software was written to test a time variant floating mean counting algorithm. The algorithm was developed by Westinghouse Savannah River Company and a provisional patent has been filed on the algorithm. The test software was developed to work with the Val Tech model IVB prototype version II count rate meter hardware. The test software was used to verify the algorithm developed by WSRC could be correctly implemented with the vendor''s hardware.

  9. Floating debris in the Mediterranean Sea.

    PubMed

    Suaria, Giuseppe; Aliani, Stefano

    2014-09-15

    Results from the first large-scale survey of floating natural (NMD) and anthropogenic (AMD) debris (>2 cm) in the central and western part of the Mediterranean Sea are reported. Floating debris was found throughout the entire study area with densities ranging from 0 to 194.6 items/km(2) and mean abundances of 24.9 AMD items/km(2) and 6.9 NMD items/km(2) across all surveyed locations. On the whole, 78% of all sighted objects were of anthropogenic origin, 95.6% of which were petrochemical derivatives (i.e. plastic and styrofoam). Maximum AMD densities (>52 items/km(2)) were found in the Adriatic Sea and in the Algerian basin, while the lowest densities (<6.3 items/km(2)) were observed in the Central Tyrrhenian and in the Sicilian Sea. All the other areas had mean densities ranging from 10.9 to 30.7 items/km(2). According to our calculations, more than 62 million macro-litter items are currently floating on the surface of the whole Mediterranean basin. PMID:25127501

  10. Capillary effects on floating cylindrical particles

    NASA Astrophysics Data System (ADS)

    Dixit, Harish N.; Homsy, G. M.

    2012-12-01

    In this study, we develop a systematic perturbation procedure in the small parameter, B1/2, where B is the Bond number, to study capillary effects on small cylindrical particles at interfaces. Such a framework allows us to address many problems involving particles on flat and curved interfaces. In particular, we address four specific problems: (i) capillary attraction between cylinders on flat interface, in which we recover the classical approximate result of Nicolson ["The interaction between floating particles," Proc. Cambridge Philos. Soc. 45, 288-295 (1949), 10.1017/S0305004100024841], thus putting it on a rational basis; (ii) capillary attraction and aggregation for an infinite array of cylinders arranged on a periodic lattice, where we show that the resulting Gibbs elasticity obtained for an array can be significantly larger than the two cylinder case; (iii) capillary force on a cylinder floating on an arbitrary curved interface, where we show that in the absence of gravity, the cylinder experiences a lateral force which is proportional to the gradient of curvature; and (iv) capillary attraction between two cylinders floating on an arbitrary curved interface. The present perturbation procedure does not require any restrictions on the nature of curvature of the background interface and can be extended to other geometries.

  11. Borofloat and Starphire Float Glasses: A Comparison

    SciTech Connect

    Wereszczak, Andrew A.; Anderson Jr., Charles E.

    2014-10-28

    Borofloat® borosilicate float glass and Starphire® soda-lime silicate float glass are used in transparent protective systems. They are known to respond differently in some ballistic and triaxial loading conditions, and efforts are underway to understand the causes of those differences. Toward that, a suite of test and material characterizations were completed in the present study on both glasses so to identify what differences exist among them. Compositional, physical properties, elastic properties, flaw size distributions and concentrations, tensile/flexure strength, fracture toughness, spherical indentation and hardness, transmission electron microscopy, striae, high pressure responses via diamond anvil cell testing, laser shock differences, and internal porosity were examined. Differences between these two float glasses were identified for many of these properties and characteristics, and the role of three (striae, high pressures where permanent densification can initiate, and sub-micron-sized porosity) lack understanding and deserve further attention. Lastly, the contributing roles of any of those properties or characteristics to triaxial or ballistic loading responses are not definitive; however, they provide potential correlations that may lead to improved understanding and management of loading responses in glasses used in transparent protective systems.

  12. Borofloat and Starphire Float Glasses: A Comparison

    DOE PAGESBeta

    Wereszczak, Andrew A.; Anderson Jr., Charles E.

    2014-10-28

    Borofloat® borosilicate float glass and Starphire® soda-lime silicate float glass are used in transparent protective systems. They are known to respond differently in some ballistic and triaxial loading conditions, and efforts are underway to understand the causes of those differences. Toward that, a suite of test and material characterizations were completed in the present study on both glasses so to identify what differences exist among them. Compositional, physical properties, elastic properties, flaw size distributions and concentrations, tensile/flexure strength, fracture toughness, spherical indentation and hardness, transmission electron microscopy, striae, high pressure responses via diamond anvil cell testing, laser shock differences, andmore » internal porosity were examined. Differences between these two float glasses were identified for many of these properties and characteristics, and the role of three (striae, high pressures where permanent densification can initiate, and sub-micron-sized porosity) lack understanding and deserve further attention. Lastly, the contributing roles of any of those properties or characteristics to triaxial or ballistic loading responses are not definitive; however, they provide potential correlations that may lead to improved understanding and management of loading responses in glasses used in transparent protective systems.« less

  13. Drill vessels float in aerated water

    SciTech Connect

    Hammett, D.S.

    1985-01-01

    Model tests, calculations, and case studies prove that a floating vessel will not sink due to gas reducing the water density in or adjacent to a subsea blowout. Several floating drill vessels have been lost as a result of subsea blowouts. Reports have circulated that the rig sank into something similar to a hole in the ocean caused by gas bubbles suspended in the water reducing its specific gravity. These erroneous reports, believed as truth by many people, have resulted in the modification of operations resulting in decreased safety. Several subsea well control operations have caused accidents and losses because the riser was not disconnected. This action was taken in fear of sinking in aerated water. The losses occurred because the vessel winched itself off the drill site to get away from the subsea well before disconnecting. Due to the high riser/BOP angle, the riser could not be disconnected and well control was later lost and the gas/oil flowed directly to the rig floor where massive fire/explosion damage occurred. If there had been a better understanding of water density, the rig personnel could have closed all hatches, shut-down all engines, disconnected the riser and released mooring lines at one end of the rig, and safely removed the rig out of the aerated water. This paper presents some of the technical data and references available which prove that a floating vessel will not sink due to loss of water density.

  14. FPP [Floating Potential Probe] Results, Final Report

    NASA Technical Reports Server (NTRS)

    Ferguson, Dale C.

    2007-01-01

    The Floating Potential Probe (FPP) operated on the International Space Station (ISS) from December 2000 to April 2001. During that time, it took many measurements of the ISS floating potential and the electron density and temperature. Those measurements were used as inputs to the Environments WorkBench (EWB) model of ISS potentials (originally developed by SAIC, but now sometimes called the Boeing model) that is used even today to predict charging levels for ISS. FPP is now completely defunct, having been removed and ejected from ISS. With the advent of the new Floating Potential Monitoring Unit (FPMU) on ISS, and the beginning of ISS operations with two large solar array panels instead of just one, a review of FPP measurements can offer comparisons with the new FPMU data and perhaps improve the accuracy of future ISS charging predictions. In particular, FPP measurements during times of low electron temperature and high electron density (the times of worst ISS charging) will be brought forward for comparison with the newly obtained FPMU data.

  15. Multiview autosterescopic display with floating real image

    NASA Astrophysics Data System (ADS)

    Kakeya, Hideki; Kobe, Naoto; Kasano, Hidehiro

    2004-05-01

    This paper proposes multiview version of autostereoscopic display FLOATS (Fresnel Lens based Optical Apparatus for Touchable-distance Stereoscopy), which combines generation of floating real image and parallax presentation to show realistic 3-D image within the viewer's reach. Earlier versions of FLOATS have required a head tracker, physical motion control of filters or mirrors, and transformation of image in accordance with the viewer's motion to keep on presenting different images to each eye. To do away with these requirements, we propose two methods which realize multiview presentation to the viewer. One method is to use multiple LCD panels and multiple fixed mirrors instead of mobile mirrors. The other method is to use mutiple projectors, fly-eye lenses, and fresnel lenses. Though the former system doesn't cost much, it is not practical to present more than 10 views. In the latter system it is practical to present more than 30 views, which can realize presentation of both horizontal and vertical parallax. With this technology the viewers can perceive undistorted 3-D space from any angle, which makes it possible for multiple viewers to observe 3-D image at consistent position from different angles at the same time.

  16. Physical implication of transition voltage in organic nano-floating-gate nonvolatile memories

    NASA Astrophysics Data System (ADS)

    Wang, Shun; Gao, Xu; Zhong, Ya-Nan; Zhang, Zhong-Da; Xu, Jian-Long; Wang, Sui-Dong

    2016-07-01

    High-performance pentacene-based organic field-effect transistor nonvolatile memories, using polystyrene as a tunneling dielectric and Au nanoparticles as a nano-floating-gate, show parallelogram-like transfer characteristics with a featured transition point. The transition voltage at the transition point corresponds to a threshold electric field in the tunneling dielectric, over which stored electrons in the nano-floating-gate will start to leak out. The transition voltage can be modulated depending on the bias configuration and device structure. For p-type active layers, optimized transition voltage should be on the negative side of but close to the reading voltage, which can simultaneously achieve a high ON/OFF ratio and good memory retention.

  17. Floating Oil-Spill Containment Device

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.

    2012-01-01

    Previous oil containment booms have an open top that allows natural gas to escape, and have significant oil leakage due to wave action. Also, a subsea pyramid oil trap exists, but cannot move relative to moving oil plumes from deepsea oil leaks. The solution is to have large, moveable oil traps. One version floats on the sea surface and has a flexible tarp cover and a lower weighted skirt to completely entrap the floating oil and natural gas. The device must have at least three sides with boats pulling at each apex, and sonar or other system to track the slowly moving oil plume, so that the boats can properly locate the booms. The oil trap device must also have a means for removal of the oil and the natural gas. A second design version has a flexible pyramid cover that is attached by lines to ballast on the ocean floor. This is similar to fixed, metal pyramid oil capture devices in the Santa Barbara Channel off the coast of California. The ballast lines for the improved design, however, would have winches that can move the pyramid to always be located above the oil and gas plume. A third design is a combination of the first two. It uses a submerged pyramid to trap oil, but has no anchor and uses boats to locate the trap. It has ballast weights located along the bottom of the tarp and/or at the corners of the trap. The improved floating oil-spill containment device has a large floating boom and weighted skirt surrounding the oil and gas entrapment area. The device is triangular (or more than three sides) and has a flexible tarp cover with a raised gas vent area. Boats pull on the apex of the triangles to maintain tension and to allow the device to move to optimum locations to trap oil and gas. The gas is retrieved from a higher buoyant part of the tarp, and oil is retrieved from the floating oil layer contained in the device. These devices can be operated in relatively severe weather, since waves will break over the devices without causing oil leaking. Also, natural

  18. Integrated use of spatial and semantic relationships for extracting road networks from floating car data

    NASA Astrophysics Data System (ADS)

    Li, Jun; Qin, Qiming; Xie, Chao; Zhao, Yue

    2012-10-01

    The update frequency of digital road maps influences the quality of road-dependent services. However, digital road maps surveyed by probe vehicles or extracted from remotely sensed images still have a long updating circle and their cost remain high. With GPS technology and wireless communication technology maturing and their cost decreasing, floating car technology has been used in traffic monitoring and management, and the dynamic positioning data from floating cars become a new data source for updating road maps. In this paper, we aim to update digital road maps using the floating car data from China's National Commercial Vehicle Monitoring Platform, and present an incremental road network extraction method suitable for the platform's GPS data whose sampling frequency is low and which cover a large area. Based on both spatial and semantic relationships between a trajectory point and its associated road segment, the method classifies each trajectory point, and then merges every trajectory point into the candidate road network through the adding or modifying process according to its type. The road network is gradually updated until all trajectories have been processed. Finally, this method is applied in the updating process of major roads in North China and the experimental results reveal that it can accurately derive geometric information of roads under various scenes. This paper provides a highly-efficient, low-cost approach to update digital road maps.

  19. An Analysis of the Full-Floating Journal Bearing

    NASA Technical Reports Server (NTRS)

    Shaw, M C; Nussdorfer, T J , Jr

    1947-01-01

    An analysis of the operating characteristics of a full-floating journal bearing, a bearing in which a floating sleeve is located between the journal and bearing surfaces, is presented together with charts from which the performance of such bearings may be predicted. Examples are presented to illustrate the use of these charts and a limited number of experiments conducted upon a glass full-floating bearing are reported to verify some results of the analysis.

  20. Characteristics of a micromachined floating-gate high-electron-mobility transistor at 4.2 K

    NASA Astrophysics Data System (ADS)

    Teh, W. H.; Crook, R.; Smith, C. G.; Beere, H. E.; Ritchie, D. A.

    2005-06-01

    We use micromachined, free-standing Ni cantilevers to develop a mechanical field-effect transistor based on III-V material systems. The device consists of an electrostatically actuated microcantilever, acting as the floating gate, fabricated over a defined two-dimensional electron gas (2DEG) in a modulation-doped GaAs /AlGaAs heterostructure. The gating effects on the conductance of the 2DEG channel of the biased floating gate at different operating points are studied at 4.2K. Preliminary resonance measurements based on the 2DEG as a deflection sensor are presented.

  1. Evaluation and floating enhancement of levodopa sustained release floating minitablets coated with insoluble acrylic polymer.

    PubMed

    Goole, J; Amighi, K; Vanderbist, F

    2008-08-01

    This article describes the in vitro evaluation and the enhancement of the floating properties of coated sustained release (SR) minitablets (MTs). The evaluated system consisted of a 3-mm drug-containing gas-generating core prepared by melt granulation and subsequent compression, which was then coated with a flexible polymeric membrane. Eudragit RL30D and acetyl triethylcitrate were used as a film former and a plasticizer, respectively. The coating level was fixed at 20% (wt/wt). The optimally coated floating MTs floated within 10 min and remained buoyant for more than 13 h, regardless of the pH of the test medium. By evaluating the dissolution profiles of levodopa at different pH, it was found that the release of levodopa was sustained for more than 12 h regardless of the pH, even if the coating did not cancel the effect of the pH-dependent solubility of the active drug. Finally, the robustness of the coated floating MTs was assessed by testing the drug release variability in function of the stirring conditions during dissolution tests. PMID:18618310

  2. Development and in vivo floating behavior of verapamil HCl intragastric floating tablets.

    PubMed

    Patel, Anand; Modasiya, Moin; Shah, Dushyant; Patel, Vishnu

    2009-01-01

    A novel gastro retentive controlled release drug delivery system of verapamil HCl was formulated in an effort to increase the gastric retention time of the dosage form and to control drug release. Hydroxypropylmethylcellulose (HPMC), carbopol, and xanthan gum were incorporated for gel-forming properties. Buoyancy was achieved by adding an effervescent mixture of sodium bicarbonate and anhydrous citric acid. In vitro drug release studies were performed, and drug release kinetics was evaluated using the linear regression method. The optimized intragastric floating tablet composed of 3:2 of HPMC K4M to xanthan gum exhibited 95.39% drug release in 24 h in vitro, while the buoyancy lag time was 36.2 s, and the intragastric floating tablet remained buoyant for >24 h. Zero-order and non-Fickian release transport was confirmed as the drug release mechanism from the optimized formulation (F7). X-ray studies showed that total buoyancy time was able to delay the gastric emptying of verapamil HCl intragastric floating tablet in mongrel dogs for more than 4 h. Optimized intragastric floating tablet showed no significant change in physical appearance, drug content, total buoyancy time, or in vitro dissolution pattern after storage at 40 degrees C/75% relative humidity for 3 months. PMID:19296224

  3. Floating production unit to work off Brazil

    SciTech Connect

    Not Available

    1992-10-19

    This paper reports that Petroleo Brasileiro SA expects by early November to deploy its Petrobras XXIV floating production unit (FPU) in about 900 ft of water in Albacora field off Brazil. The FPU was scheduled to depart Galveston, Tex., this month, following completion of modifications and upgrades under a turnkey contract with Chiles Offshore International Inc. Chiles began modifying Petrobras XXIV about 1 year ago as part of a deal closed in October 1991 in which Chiles Offshore Corp. sold the vessel, then known as Intrepid, to Brasoil, the international subsidiary of Petrobras.

  4. Floating hydrometer with energy dissipating baffle

    SciTech Connect

    Kownurko, W.A.

    1987-11-24

    This patent describes a floating hydrometer employable for purposes of obtaining measurements of the presence of suspended solids in a fluid substance contained in a receptacle comprising: a. a probe portion operative as an instrument-bearing housing; b. an elongated tubular element having a hollow interior and at least one open end so as to enable the flow into the hollow interior of the elongated tubular element through the open end; and c. energy dissipating baffle means having a first mode of action and a second mode of action and including a member having a hollow interior.

  5. Floating air riding seal for a turbine

    DOEpatents

    Ebert, Todd A

    2016-08-16

    A floating air riding seal for a gas turbine engine with a rotor and a stator, an annular piston chamber with an axial moveable annular piston assembly within the annular piston chamber formed in the stator, an annular cavity formed on the annular piston assembly that faces a seal surface on the rotor, where the axial moveable annular piston includes an inlet scoop on a side opposite to the annular cavity that scoops up the swirling cooling air and directs the cooling air to the annular cavity to form an air cushion with the seal surface of the rotor.

  6. Analysis of a Near-Free-Floating Vibration Isolation Platform

    NASA Astrophysics Data System (ADS)

    Regehr, M.

    2015-02-01

    Pointing control for deep-space lasercom is expected to be challenging because, for the apertures and wavelengths contemplated (of order 20 cm and 1 micrometer, respectively), the width of the beam transmitting data to Earth will be of order a few microradians. To address this challenge, JPL and others have been developing a vibration isolation system in which the lasercom telescope is nearly free-floating next to the spacecraft, being physically connected to the spacecraft only by a set of flexible wires and fibers referred to as an umbilical. The telescope's position relative to the spacecraft is sensed by noncontact sensors and the telescope is controlled by noncontact (voice coil) actuators. The telescope pointing error, relative to Earth, is also sensed by a pointing detector in the telescope, which images an Earth-based laser beacon. The telescope moves in six degrees of freedom, of which two (pitch and yaw) are the pointing of the telescope, and are of principal importance. This article describes a controller for controlling the telescope, and a simplified method of analyzing the closed-loop behavior of the system. Several mechanisms for cross-coupling between the degrees of freedom are present, including off-diagonal elements in the umbilical spring constant matrix, and the telescope having significant products of inertia; as a result, the dynamics of the closed-loop system are described by a full 6 by 6 transfer matrix. Approximations that take into account only one or two cross-coupling mechanisms at a time, however, and which result in block-diagonal models for the system, provide excellent agreement with the full model. These approximations provide insight useful for designing the controller, and numerical models indicate that a controller designed using these approximations provides performance that meets pointing requirements.

  7. Drilling and production from a floating spar

    SciTech Connect

    Brooks, I.H.; Carroll, J.P.

    1994-12-31

    A deepwater drilling and production platform has been designed based on a floating spar. The spar is a catenary-moored cylindrical vessel having a deep draft which minimizes heave motions. The concept is an economic competitor with other deep water designs such as compliant towers and tension leg platforms. The spar`s oil storage capacity makes it particularly applicable for remote areas where pipeline infrastructure is unavailable and production is primarily from oil reservoirs. Without the need for a swivel, offloading of oil can be accomplished either directly from the spar, by use of a floating hose and support vessel, or by transfer to an offloading buoy. The concept is compatible with early production or phased development scenarios, permits surface completions of producing and injection wells, and allows for direct well intervention. The ability to reposition the spar by manipulations of the mooring lines favors a system of individual wellheads on the seafloor. Wells can be drilled, completed, and produced without pulling the drilling riser. When production from the field reaches its economic limit, the entire system can be towed to a new location and reused.

  8. Floating treatment wetlands for domestic wastewater treatment.

    PubMed

    Faulwetter, J L; Burr, M D; Cunningham, A B; Stewart, F M; Camper, A K; Stein, O R

    2011-01-01

    Floating islands are a form of treatment wetland characterized by a mat of synthetic matrix at the water surface into which macrophytes can be planted and through which water passes. We evaluated two matrix materials for treating domestic wastewater, recycled plastic and recycled carpet fibers, for chemical oxygen demand (COD) and nitrogen removal. These materials were compared to pea gravel or open water (control). Experiments were conducted in laboratory scale columns fed with synthetic wastewater containing COD, organic and inorganic nitrogen, and mineral salts. Columns were unplanted, naturally inoculated, and operated in batch mode with continuous recirculation and aeration. COD was efficiently removed in all systems examined (>90% removal). Ammonia was efficiently removed by nitrification. Removal of total dissolved N was ∼50% by day 28, by which time most remaining nitrogen was present as NO(3)-N. Complete removal of NO(3)-N by denitrification was accomplished by dosing columns with molasses. Microbial communities of interest were visualized with denaturing gradient gel electrophoresis (DGGE) by targeting specific functional genes. Shifts in the denitrifying community were observed post-molasses addition, when nitrate levels decreased. The conditioning time for reliable nitrification was determined to be approximately three months. These results suggest that floating treatment wetlands are a viable alternative for domestic wastewater treatment. PMID:22105133

  9. Evaporation mitigation using floating modular devices

    NASA Astrophysics Data System (ADS)

    Hassan, M. Mahmudul; Peirson, William Leslie; Neyland, Bryce M.; Fiddis, Nicholas McQuistan

    2015-11-01

    Reducing evaporation losses from open water storages is of paramount importance in the improvement of water security in arid countries, including Australia. Widespread adoption of evaporation mitigation techniques has been prevented by their high capital and maintenance or operating costs. The use of clean, floating recycled materials to mitigate evaporation technique has been investigated systematically at sites within both the coastal and semi-arid zones of Australia. Evaporation reduction systematically increases with the proportion of covered surface. Evaporation is reduced by 43% at coastal site and 37% at arid zone site at the maximum packing densities achievable for a single layer of floating devices. The study highlights the importance of both long-term investigations and the climatic influences in the robust quantification of evaporation mitigation. The effects of solar radiation, temperature, wind speed and relative humidity on the evaporation rate at both study sites have been determined in terms of both the classical Penman model and FAO Penman Monteith model with corresponding pan coefficients quantified. FAO Penman Monteith model better estimates evaporation from the open reference tank.

  10. Modal testing variability of spherical marine floats.

    SciTech Connect

    Robertson, A. N.; Hemez, F. M.; Salazar, I. F.; Duffey, T. A.

    2004-01-01

    This study investigates the variability in modal data obtained from testing a set of hollow, almost spherical marine floats. Four sources of variability are investigated: unit-to -unit variability, operator-to-operator variability, test repetition, and accelerometer placement. Because moving the accelerometers implies a test setup reconfiguration, it is expected that variability due to accelerometer placement should encompass variability due to test repetition. Similarly, the unit-to-unit variability should encompass both accelerometer placement variability and test-to -test variability. Impulse and frequency response functions are estimated from the measured excitation and response of the marine floats. A series of techniques are then used to assess the variation of the modal properties between each test, including: a measure of the spread of the frequency response functions in each test group; the variation of the temporal moments, spectral moments, and principal components; and the variability of resonant frequencies and modal damping ratios extracted from the data. The effects of mass and geometry on variability are also investigated. A strong correlation between the frequency and mass is found for the fundamental mode only. The main conclusion is that the majority of analysis techniques find the unit-to-unit variability to be the largest by a significant margin. The second largest is the variability caused by accelerometer placement. Next are the operator-to-operator variability and test-to -test variability.

  11. Water-Pressure Distribution on Seaplane Float

    NASA Technical Reports Server (NTRS)

    Thompson, F L

    1929-01-01

    The investigation presented in this report was conducted for the purpose of determining the distribution and magnitude of water pressures likely to be experienced on seaplane hulls in service. It consisted of the development and construction of apparatus for recording water pressures lasting one one-hundredth second or longer and of flight tests to determine the water pressures on a UO-1 seaplane float under various conditions of taxiing, taking off, and landing. The apparatus developed was found to operate with satisfactory accuracy and is suitable for flight tests on other seaplanes. The tests on the UO-1 showed that maximum pressures of about 6.5 pounds per square inch occur at the step for the full width of the float bottom. Proceeding forward from the step the maximum pressures decrease in magnitude uniformly toward the bow, and the region of highest pressures narrows toward the keel. Immediately abaft the step the maximum pressures are very small, but increase in magnitude toward the stern and there once reached a value of about 5 pounds per square inch. (author)

  12. Evaporation mitigation by floating modular devices

    NASA Astrophysics Data System (ADS)

    Hassan, M. M.; Peirson, W. L.

    2016-05-01

    Prolonged periods of drought and consequent evaporation from open water bodies in arid parts of Australia continue to be a threat to water availability for agricultural production. Over many parts of Australia, the annual average evaporation exceeds the annual precipitation by more than 5 times. Given its significance, it is surprising that no evaporation mitigation technique has gained widespread adoption to date. High capital and maintenance costs of manufactured products are a significant barrier to implementation. The use of directly recycled clean plastic containers as floating modular devices to mitigate evaporation has been investigated for the first time. A six-month trial at an arid zone site in Australia of this potential cost effective solution has been undertaken. The experiment was performed using clean conventional drinking water bottles as floating modules on the open water surface of 240-L tanks with three varying degrees of covering (nil, 34% and 68%). A systematic reduction in evaporation is demonstrated during the whole study period that is approximately linearly proportional to the covered surface. These results provide a potential foundation for robust evaporation mitigation with the prospect of implementing a cost-optimal design.

  13. Thermal Performance of the LDX Floating Coil

    NASA Astrophysics Data System (ADS)

    Zhukovsky, A.; Garnier, D. T.; Radovinsky, A. L.

    2006-04-01

    The Levitated Dipole Experiment (LDX) is an innovative facility to study plasma confinement in a dipole magnetic field, created by a superconducting solenoid (floating coil), which is magnetically levitated in the center of a 5 m diameter by 3 m tall vacuum chamber. The floating coil (F-coil) consists of a Nb3Sn magnet installed inside a strong vessel filled with high-pressure helium gas at room temperature. It is surrounded by a fiberglass-lead composite radiation shield and by a toroidal vacuum shell. The cryostat design provides the ability to operate the magnet for several hours of wanning while suspended in the middle of the vacuum chamber without electric and cryogenic connections to the coil. For this reason the magnet is charged/discharged inductively in a lower part of the vacuum chamber. The retractable cryogenic transfer lines serve to cool down the magnet to 4.5 K before it is lifted to the operating position. The F-coil can be re-cooled multiple times while maintaining its field and current. This paper describes the thermal performance of the F-coil.

  14. A laboratory study of floating lenticular anticyclones

    NASA Astrophysics Data System (ADS)

    Le Gal, Patrice; de La Rosa, Hector; Cros, Anne; Cruz-Gomez, Raúl; Le Bars, Michael

    2014-11-01

    Oceanic vortices play an important role in the redistribution of heat, salt and momentum in the oceans. Among these vortices, floating lenses or rings are often met in the meanders of warm currents. For instance the North Brazil Current rings are among the most intense and large anticyclonic vortices on Earth. In order to better describe these vortices, we propose here a laboratory study of these floating anticyclonic lenses. A blob of fresh water is slowly injected near the surface of a rotating layer of homogeneous salted water. Because of the opposite effects of rotation that tends to generate columnar structures and density stratification that spreads light water on the surface, the vortices take a finite size three dimensionnal typical shape. Visualization and PIV measurements of the shape, aspect ratios and vorticity profiles are compared to analytical predictions that use first a simple solid body rotation model and then a more realistic isolated Gaussian vorticity field inside the anticyclones. This work was carried out within the framework of a bilateral cooperation between CNRS (France) and CONACYT (Mexico).

  15. 40 CFR 63.1043 - Standards-Separator floating roof.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Standards-Separator floating roof. 63...) National Emission Standards for Oil-Water Separators and Organic-Water Separators § 63.1043 Standards—Separator floating roof. (a) This section applies to owners and operators subject to this subpart...

  16. 14 CFR 136.11 - Helicopter floats for over water.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Helicopter floats for over water. 136.11... floats for over water. (a) A helicopter used in commercial air tours over water beyond the shoreline must... controls, and (2) The flotation system armed when the helicopter is over water and is flying at a...

  17. 14 CFR 136.11 - Helicopter floats for over water.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Helicopter floats for over water. 136.11... floats for over water. (a) A helicopter used in commercial air tours over water beyond the shoreline must... controls, and (2) The flotation system armed when the helicopter is over water and is flying at a...

  18. 14 CFR 136.11 - Helicopter floats for over water.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Helicopter floats for over water. 136.11... floats for over water. (a) A helicopter used in commercial air tours over water beyond the shoreline must... controls, and (2) The flotation system armed when the helicopter is over water and is flying at a...

  19. 14 CFR 136.11 - Helicopter floats for over water.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Helicopter floats for over water. 136.11... floats for over water. (a) A helicopter used in commercial air tours over water beyond the shoreline must... controls, and (2) The flotation system armed when the helicopter is over water and is flying at a...

  20. 14 CFR 136.11 - Helicopter floats for over water.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Helicopter floats for over water. 136.11... floats for over water. (a) A helicopter used in commercial air tours over water beyond the shoreline must... controls, and (2) The flotation system armed when the helicopter is over water and is flying at a...

  1. 33 CFR 144.01-1 - Life floats.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Life floats. 144.01-1 Section 144.01-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-1 Life floats. Each...

  2. 14 CFR 27.521 - Float landing conditions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ....473(b) or assumed to be equal to that determined for wheel landing gear): (a) Up-load conditions in... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Float landing conditions. 27.521 Section 27... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Strength Requirements Water Loads § 27.521 Float...

  3. 14 CFR 29.521 - Float landing conditions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... factor is determined under § 29.473(b) or assumed to be equal to that determined for wheel landing gear... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Float landing conditions. 29.521 Section 29... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Strength Requirements Water Loads § 29.521 Float...

  4. 14 CFR 27.521 - Float landing conditions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Float landing conditions. 27.521 Section 27.521 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Strength Requirements Water Loads § 27.521 Float landing conditions. If certification for...

  5. 14 CFR 29.521 - Float landing conditions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Float landing conditions. 29.521 Section 29.521 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Strength Requirements Water Loads § 29.521 Float landing conditions. If certification for...

  6. 14 CFR 29.521 - Float landing conditions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... factor is determined under § 29.473(b) or assumed to be equal to that determined for wheel landing gear... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Float landing conditions. 29.521 Section 29... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Strength Requirements Water Loads § 29.521 Float...

  7. 14 CFR 27.521 - Float landing conditions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ....473(b) or assumed to be equal to that determined for wheel landing gear): (a) Up-load conditions in... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Float landing conditions. 27.521 Section 27... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Strength Requirements Water Loads § 27.521 Float...

  8. 22. Float located adjacent to entry stair in filtration bed. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. Float located adjacent to entry stair in filtration bed. The float actuates a valve that maintains water level over the bed. - Lake Whitney Water Filtration Plant, Filtration Plant, South side of Armory Street between Edgehill Road & Whitney Avenue, Hamden, New Haven County, CT

  9. 40 CFR 65.44 - External floating roof (EFR).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 16 2012-07-01 2012-07-01 false External floating roof (EFR). 65.44 Section 65.44 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Storage Vessels § 65.44 External floating roof (EFR). (a) EFR design requirements. The owner or operator...

  10. 14 CFR 23.535 - Auxiliary float loads.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Auxiliary float loads. 23.535 Section 23.535 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Structure Water Loads § 23.535 Auxiliary float loads. (a)...

  11. Electrowetting in a water droplet with a movable floating substrate

    NASA Astrophysics Data System (ADS)

    Shahzad, Amir; Masud, A. R.; Song, Jang-Kun

    2016-05-01

    Electrowetting (EW) enables facile manipulation of a liquid droplet on a hydrophobic surface. In this study, manipulation of an electrolyte droplet having a small floating object on it was investigated on a solid hydrophobic substrate under the EW process. Herein, the floating object exhibited a vertical motion under an applied electric field owing to the spreading and contraction of the droplet on its connecting substrates. The field-induced height variation of the floating object was significantly influenced by the thicknesses of the dielectric and hydrophobic materials. A small mass was also placed on the top floating object and its effect on the spreading of the droplet was observed. In this system, the height of the top floating object is precisely controllable under the application of an electric voltage. The proposed system is expected to be highly useful in the design of nano- and micro-oscillatory systems for microengineering.

  12. Effect of a floating electrode on a plasma jet

    SciTech Connect

    Hu, J. T.; Wang, J. G.; Liu, X. Y.; Liu, D. W.; Lu, X. P.; Shi, J. J.; Ostrikov, K.

    2013-08-15

    Two kinds of floating electrode, floating dielectric barrier covered electrode (FDBCE) and floating pin electrode (FPE), which can enhance the performance of plasma jet are reported. The intense discharge between the floating electrode and power electrode decreased the voltage to trigger the plasma jet substantially. The transition of plasma bullet from ring shape to disk shape in the high helium concentration region happened when the floating electrode was totally inside the powered ring electrode. The enhanced electric field between propagating plasma bullet and ground electrode is the reason for this transition. The double plasma bullets happened when part of the FDBCE was outside the powered ring electrode, which is attributed to the structure and surface charge of FDBCE. As part of the FPE was outside the powered ring electrode, the return stroke resulted in a single intensified plasma channel between FPE and ground electrode.

  13. Electrowetting in a water droplet with a movable floating substrate.

    PubMed

    Shahzad, Amir; Masud, A R; Song, Jang-Kun

    2016-05-01

    Electrowetting (EW) enables facile manipulation of a liquid droplet on a hydrophobic surface. In this study, manipulation of an electrolyte droplet having a small floating object on it was investigated on a solid hydrophobic substrate under the EW process. Herein, the floating object exhibited a vertical motion under an applied electric field owing to the spreading and contraction of the droplet on its connecting substrates. The field-induced height variation of the floating object was significantly influenced by the thicknesses of the dielectric and hydrophobic materials. A small mass was also placed on the top floating object and its effect on the spreading of the droplet was observed. In this system, the height of the top floating object is precisely controllable under the application of an electric voltage. The proposed system is expected to be highly useful in the design of nano- and micro-oscillatory systems for microengineering. PMID:27300973

  14. Children's knowledge of hierarchical phrase structure: quantifier floating in Japanese.

    PubMed

    Suzuki, Takaaki; Yoshinaga, Naoko

    2013-06-01

    The interpretation of floating quantifiers in Japanese requires knowledge of hierarchical phrase structure. However, the input to children is insufficient or even misleading, as our analysis indicates. This presents an intriguing question on learnability: do children interpret floating quantifiers based on a structure-dependent rule which is not obvious in the input or do they employ a sentence comprehension strategy based on the available input? Two experiments examined four- to six-year-old Japanese-speaking children for their interpretations of floating quantifiers in SOV and OSV sentences. The results revealed that no child employed a comprehension strategy in terms of the linear ordering of constituents, and most five- and six-year-olds correctly interpreted floating quantifiers when word-order difficulty was reduced. These facts indicate that children's interpretation of floating quantifiers is structurally dependent on hierarchical phrase structure, suggesting that this knowledge is a part of children's grammar despite the insufficient input available to them. PMID:22850618

  15. Discrete Element Modelling of Floating Debris

    NASA Astrophysics Data System (ADS)

    Mahaffey, Samantha; Liang, Qiuhua; Parkin, Geoff; Large, Andy; Rouainia, Mohamed

    2016-04-01

    Flash flooding is characterised by high velocity flows which impact vulnerable catchments with little warning time and as such, result in complex flow dynamics which are difficult to replicate through modelling. The impacts of flash flooding can be made yet more severe by the transport of both natural and anthropogenic debris, ranging from tree trunks to vehicles, wheelie bins and even storage containers, the effects of which have been clearly evident during recent UK flooding. This cargo of debris can have wide reaching effects and result in actual flood impacts which diverge from those predicted. A build-up of debris may lead to partial channel blockage and potential flow rerouting through urban centres. Build-up at bridges and river structures also leads to increased hydraulic loading which may result in damage and possible structural failure. Predicting the impacts of debris transport; however, is difficult as conventional hydrodynamic modelling schemes do not intrinsically include floating debris within their calculations. Subsequently a new tool has been developed using an emerging approach, which incorporates debris transport through the coupling of two existing modelling techniques. A 1D hydrodynamic modelling scheme has here been coupled with a 2D discrete element scheme to form a new modelling tool which predicts the motion and flow-interaction of floating debris. Hydraulic forces arising from flow around the object are applied to instigate its motion. Likewise, an equivalent opposing force is applied to fluid cells, enabling backwater effects to be simulated. Shock capturing capabilities make the tool applicable to predicting the complex flow dynamics associated with flash flooding. The modelling scheme has been applied to experimental case studies where cylindrical wooden dowels are transported by a dam-break wave. These case studies enable validation of the tool's shock capturing capabilities and the coupling technique applied between the two numerical

  16. STM imaging of electrically floating islands

    NASA Astrophysics Data System (ADS)

    Realpe, H.; Shamir, N.; Mintz, M. H.; Manassen, Y.

    2006-07-01

    Appearances and disappearances of Gd islands grown on top of a W(1 1 0) substrate were observed in time scales of hours after exposing the surface to a few Langmuirs of hydrogen. The phenomenon is presented and explained in terms of (temporary) creation of electrically floating islands, due to electrical decoupling of the island and substrate by the hydrogen that diffuses into the island/substrate interface. The disappearance of such an island is explained by forming a double barrier junction consisting of two tunneling barriers in series, causing, by charging, the potential of the island to become equal to that of the tip. The island then becomes "invisible" and the tip follows the corrugation of the surface under the substrate. The reappearance follows hydrogen mobility that retains the electrical conductivity of the island-substrate interface.

  17. Phytoremediation of perchlorate by free floating macrophytes.

    PubMed

    Bhaskaran, Krishnakumar; Vijaya Nadaraja, Anupama; Tumbath, Soumya; Babu Shah, Liji; Gangadharan Puthiya Veetil, Prajeesh

    2013-09-15

    Phytoremediation of perchlorate by free floating macrophytes (Eichornia, Pistia, Salvinia and Lemna) was evaluated in this study. Among the plants tested, Pistia showed 63.8 ± 4% (w/v) removal of 5 mg/L level perchlorate in 7 days, whereas the removal was absent in other plants. Phyto-accumulation (18.2%) and rhizo-degradation (45.68%) were identified as the mechanisms involved in perchlorate removal in Pistia. Whole plant extraction yielded 45.4 μg perchlorate/g dry weight biomass in 7 days period. High intensity of light and presence of nitrate negatively affected perchlorate removal by Pistia. An enrichment of Pistia root homogenate exhibited faster reduction of perchlorate where 100mg/L of the compound was reduced completely in 48 h under anoxic condition. A novel perchlorate reducing bacterium, isolated from Pistia root homogenate enrichment was identified as Acinetobacter sp. NIIST (Genbank JX467695). PMID:23872336

  18. Floating Vitreous Cyst: Two Clinical Cases

    PubMed Central

    Lavric, Alenka; Urbancic, Mojca

    2013-01-01

    Purpose To report two cases of solitary unilateral vitreous cyst. Methods A complete ocular examination, fundus photography, B-scan ultrasound and spectral-domain optical coherence tomography were performed in both patients. Results The first patient (a 39-year-old man) presented with transient blurred vision in the right eye. The second patient (a 78-year-old man) reported transient blurred vision in the right eye when changing head position. He was referred to the Eye Hospital because of vitreomacular traction in the other eye. After examination, a diagnosis of vitreous cyst was made in both cases. Conclusions Vitreous cysts are rare clinical findings. They can occur in normal eyes or in eyes with certain ocular pathologies. When a cyst floats into the visual axis area, it can disturb visual function; therefore, patients usually report transient blurring of vision. A prompt clinical examination is necessary for differentiating this rare condition. PMID:24348410

  19. Fresh look at floating shock fitting

    NASA Technical Reports Server (NTRS)

    Hartwich, PETER-M.

    1990-01-01

    A fast implicit upwind procedure for the two-dimensional Euler equations is described that allows accurate computations of shocked flows on nonadapted meshes. Away from shocks, the second-order accurate upwinding is based on the split-coefficient-matrix (SCM) method. In the presence of shocks, the difference stencils are modified using a floating shock fitting technique. Rapid convergence to steady-state solutions is attained with a diagonalized approximate factorization (AF) algorithm. Results are presented for Riemann's problem, for a regular shock reflection at an inviscid wall, for supersonic flow past a cylinder, and for a transonic airfoil. All computed shocks are ideally sharp and in excellent agreement with other numerical results or 'exact' solutions. Most importantly, this has been accomplished on unusually crude meshes without any attempt to align grid lines with shock fronts or to cluster grid lines around shocks.

  20. Capillary self-assembly of floating bodies

    NASA Astrophysics Data System (ADS)

    Jung, Sunghwan; Thompson, Paul; Bush, John

    2007-11-01

    We study the self-assembly of bodies supported on the water surface by surface tension. Attractive and repulsive capillary forces exist between menisci of, respectively, the same and opposite signs. In nature, floating objects (e.g. mosquito larvae) thus interact through capillary forces to form coherent packings on the water surface. We here present the results of an experimental investigation of such capillary pattern formation. Thin elliptical metal sheets were designed to have variable shape, flexibility and mass distribution. On the water surface, mono-, bi-, or tri-polar menisci could thus be achieved. The influence of the form of the menisci on the packings arising from the interaction of multiple floaters is explored. Biological applications are discussed.

  1. Nuclear Security for Floating Nuclear Power Plants

    SciTech Connect

    Skiba, James M.; Scherer, Carolynn P.

    2015-10-13

    Recently there has been a lot of interest in small modular reactors. A specific type of these small modular reactors (SMR,) are marine based power plants called floating nuclear power plants (FNPP). These FNPPs are typically built by countries with extensive knowledge of nuclear energy, such as Russia, France, China and the US. These FNPPs are built in one country and then sent to countries in need of power and/or seawater desalination. Fifteen countries have expressed interest in acquiring such power stations. Some designs for such power stations are briefly summarized. Several different avenues for cooperation in FNPP technology are proposed, including IAEA nuclear security (i.e. safeguards), multilateral or bilateral agreements, and working with Russian design that incorporates nuclear safeguards for IAEA inspections in non-nuclear weapons states

  2. Porous carrier based floating granular delivery system of repaglinide.

    PubMed

    Jain, Sunil K; Agrawal, Govind P; Jain, Narendra K

    2007-04-01

    A floating granular delivery system consisting of calcium silicate (CS) as porous carrier; repaglinide (Rg), an oral hypoglycemic agent; and hydroxypropyl methylcellulose K4M (HPMC K4M), ethyl cellulose (EC) and carbopol 940 (CP940) as matrix forming polymers was prepared and evaluated for its gastro-retentive and controlled release properties. The effect of various formulation and process variables on the particle morphology, micromeritic properties, in vitro floating behavior, drug content (%) and in vitro drug release was studied. The transit of floating granules of optimized formulation in the gastrointestinal (GI) tract was monitored by gamma scintigraphy in albino rabbits. The optimized formulation was compared in vivo with lactose granules (RgSCLG) prepared from identical polymers with their optimized composition ratio. Repaglinide-loaded optimized formulation was orally administered to albino rabbits and blood samples collected were used to determine pharmacokinetic parameters of Rg from floating granular formulation. Results were compared with pharmacokinetic parameters of marketed tablet formulation of Rg. The optimized formulation (RgSCG4) demonstrated favorable in vitro floating and release characteristics. Prolonged gastric residence time (GRT) of over 6 hr was achieved in all subjects for calcium silicate based floating granules of Rg. The relative bioavailability of Rg-loaded floating granules increased 3.8-fold in comparison to that of its marketed capsule. The designed system, combining excellent buoyant ability and suitable drug release pattern, offered clear advantages in terms of increased bioavailability of repaglinide. PMID:17523003

  3. WindWaveFloat (WWF): Final Scientific Report

    SciTech Connect

    Alla Weinstein; Roddier, Dominique; Banister, Kevin

    2012-03-30

    Principle Power Inc. and National Renewable Energy Lab (NREL) have completed a contract to assess the technical and economic feasibility of integrating wave energy converters into the WindFloat, resulting in a new concept called the WindWaveFloat (WWF). The concentration of several devices on one platform could offer a potential for both economic and operational advantages. Wind and wave energy converters can share the electrical cable and power transfer equipment to transport the electricity to shore. Access to multiple generation devices could be simplified, resulting in cost saving at the operational level. Overall capital costs may also be reduced, provided that the design of the foundation can be adapted to multiple devices with minimum modifications. Finally, the WindWaveFloat confers the ability to increase energy production from individual floating support structures, potentially leading to a reduction in levelized energy costs, an increase in the overall capacity factor, and greater stability of the electrical power delivered to the grid. The research conducted under this grant investigated the integration of several wave energy device types into the WindFloat platform. Several of the resulting system designs demonstrated technical feasibility, but the size and design constraints of the wave energy converters (technical and economic) make the WindWaveFloat concept economically unfeasible at this time. Not enough additional generation could be produced to make the additional expense associated with wave energy conversion integration into the WindFloat worthwhile.

  4. Drift trajectories of a floating human body simulated in a hydraulic model of Puget Sound.

    PubMed

    Ebbesmeyer, C C; Haglund, W D

    1994-01-01

    After a young man jumped off a 221-foot (67 meters) high bridge, the drift of the body that beached 20 miles (32 km) away at Alki Point in Seattle, Washington was simulated with a hydraulic model. Simulations for the appropriate time period were performed using a small floating bead to represent the body in the hydraulic model at the University of Washington. Bead movements were videotaped and transferred to Computer Aided Drafting (AutoCAD) charts on a personal computer. Because of strong tidal currents in the narrow passage under the bridge (The Narrows near Tacoma, WA), small changes in the time of the jump (+/- 30 minutes) made large differences in the distance the body traveled (30 miles; 48 km). Hydraulic and other types of oceanographic models may be located by contacting technical experts known as physical oceanographers at local universities, and can be utilized to demonstrate trajectories of floating objects and the time required to arrive at selected locations. Potential applications for forensic death investigators include: to be able to set geographic and time limits for searches; determine potential origin of remains found floating or beached; and confirm and correlate information regarding entry into the water and sightings of remains. PMID:8113703

  5. Analysis of Static Spacecraft Floating Potential at Low Earth Orbit (LEO)

    NASA Technical Reports Server (NTRS)

    Herr, Joel L.; Hwang, K. S.; Wu, S. T.

    1995-01-01

    Spacecraft floating potential is the charge on the external surfaces of orbiting spacecraft relative to the space. Charging is caused by unequal negative and positive currents to spacecraft surfaces. The charging process continues until the accelerated particles can be collected rapidly enough to balance the currents at which point the spacecraft has reached its equilibrium or floating potential. In low inclination. Low Earth Orbit (LEO), the collection of positive ion and negative electrons. in a particular direction. are typically not equal. The level of charging required for equilibrium to be established is influenced by the characteristics of the ambient plasma environment. by the spacecraft motion, and by the geometry of the spacecraft. Using the kinetic theory, a statistical approach for studying the interaction is developed. The approach used to study the spacecraft floating potential depends on which phenomena are being applied. and on the properties of the plasma. especially the density and temperature. The results from kinetic theory derivation are applied to determine the charging level and the electric potential distribution at an infinite flat plate perpendicular to a streaming plasma using finite-difference scheme.

  6. Road Network Generalization Based on Float CAR Tracking

    NASA Astrophysics Data System (ADS)

    Zhou, Cheng; Li, Wenjing; Jia, Hongguo

    2016-06-01

    Road generalization is not only helpful to simplify complicated road networks but can also satisfy the needs of reasonable display of roads under varying scales, thus offering basis for updating and grading urban roads. This paper proposes a selection method for road network generalization by integrating road-associated vehicle trajectory dynamic properties and road features and calculating the importance of urban roads. First of all, the location and motion information of floating vehicles are associated to relevant roads to generate the dynamic properties of roads. Then, the dynamic and static properties of roads are analyzed, and the cluster analysis is conducted to the trajectory points at road intersections to obtain the importance of some road intersections there are vehicles passing by. Afterwards, the weights of roads are calculated using the dominance rough set, the roads are ranked by weight and the practical significance of ranking results is analyzed. Finally, the selection rules for the basic framework of road network are determined to meet with different requirements and guarantee both connectivity and completeness of road networks. The results show that the relative importance of roads is made clear by taking advantage of the rough set and the generalized road network highlights the distribution and connection of urban main roads.

  7. Floating oil production unit slated in small field off Gabon

    SciTech Connect

    Not Available

    1991-10-14

    This paper reports on the first U.S. tanker converted to a floating production, storage, and offloading (FPSO) unit which takes up station in Gombe-Beta field off Gabon by Dec. 1. FPSO Ocean Producer will work under a 3 year, day rate contract let late in 1990 by Amoco-Gabon Bombe Marin co., a unit of Amoco Production Co. (OGJ, Dec. 24, 1990, p. 27). Gombe-Beta field is in the Atlantic Ocean about 70 miles south of Port Gentil, Gabon. Ocean Producer will be moored in 50 ft of water 3.7 miles off Gabon, with Bombe-Beta's unmanned production platform about 820 ft astern. The vessel will be held in position by a disconnectable, asymmetric, six point, spread mooring system, It is owned and operated by Oceaneering International Services Ltd. (OISL). Affiliate Oceaneering Production Systems (OPS) converted the 78,061 dwt oil tanker MT Baltimore Sea at a capital cost of $25 million at Gulf Copper Manufacturing Corp.'s Port Arthur, Tex., shipyard. Both companies are units of Oceaneering International Inc., Houston. OPS the Ocean Producer's use in Gombe-Beta field is the shallowest water FPSO application in the world. Amoco-Gabon chose an FPSO production system for Gombe-Beta because it expects the remote field to have a short economic life, and the oil requires extensive processing.

  8. Strongly Emitting Surfaces Unable to Float below Plasma Potential

    NASA Astrophysics Data System (ADS)

    Campanell, M. D.; Umansky, M. V.

    2016-02-01

    An important unresolved question in plasma physics concerns the effect of strong electron emission on plasma-surface interactions. Previous papers reported solutions with negative and positive floating potentials relative to the plasma edge. The two models give very different predictions for particle and energy balance. Here we show that the positive potential state is the only possible equilibrium in general. Even if a negative floating potential existed at t =0 , the ionization collisions near the surface will force a transition to the positive floating potential state. This transition is demonstrated with a new simulation code.

  9. Strongly Emitting Surfaces Unable to Float below Plasma Potential

    DOE PAGESBeta

    Campanell, M. D.; Umansky, M. V.

    2016-02-25

    One important unresolved question in plasma physics concerns the effect of strong electron emission on plasma-surface interactions. Previous papers reported solutions with negative and positive floating potentials relative to the plasma edge. For these two models a very different predictions for particle and energy balance is given. Here we show that the positive potential state is the only possible equilibrium in general. Even if a negative floating potential existed at t=0, the ionization collisions near the surface will force a transition to the positive floating potential state. Moreover, this transition is demonstrated with a new simulation code.

  10. Float level switch for a nuclear power plant containment vessel

    DOEpatents

    Powell, James G.

    1993-01-01

    This invention is a float level switch used to sense rise or drop in water level in a containment vessel of a nuclear power plant during a loss of coolant accident. The essential components of the device are a guide tube, a reed switch inside the guide tube, a float containing a magnetic portion that activates a reed switch, and metal-sheathed, ceramic-insulated conductors connecting the reed switch to a monitoring system outside the containment vessel. Special materials and special sealing techniques prevent failure of components and allow the float level switch to be connected to a monitoring system outside the containment vessel.

  11. Float level switch for a nuclear power plant containment vessel

    DOEpatents

    Powell, J.G.

    1993-11-16

    This invention is a float level switch used to sense rise or drop in water level in a containment vessel of a nuclear power plant during a loss of coolant accident. The essential components of the device are a guide tube, a reed switch inside the guide tube, a float containing a magnetic portion that activates a reed switch, and metal-sheathed, ceramic-insulated conductors connecting the reed switch to a monitoring system outside the containment vessel. Special materials and special sealing techniques prevent failure of components and allow the float level switch to be connected to a monitoring system outside the containment vessel. 1 figures.

  12. Recent advances in gastric floating drug delivery technology: a review.

    PubMed

    Pahwa, Rakesh; Bisht, Seema; Kumar, Vipin; Kohli, Kanchan

    2013-06-01

    Gastric floating drug delivery systems have been an avenue of considerable interest in terms of their immense potential for better pharmacotherapeutic interventions along with site-specific absorption. These buoyant systems significantly enhance the bioavailability and controlled delivery of several drug molecules. Scientific investigators have also carried out substantial research endeavours worldwide in order to design a more systematic and intellectual floating systems. The present manuscript is an attempt to highlight numerous recent advancements in the design of gastric floating drug delivery systems along with various available commercial preparations. Salient applications, characterization aspects and future perspectives of these multifarious systems have also been addressed. PMID:23808593

  13. Radiation Issues and Applications of Floating Gate Memories

    NASA Technical Reports Server (NTRS)

    Scheick, L. Z.; Nguyen, D. N.

    2000-01-01

    The radiation effects that affect various systems that comprise floating gate memories are presented. The wear-out degradation results of unirradiated flash memories are compared to irradiated flash memories. The procedure analyzes the failure to write and erase caused by wear-out and degradation of internal charge pump circuits. A method is described for characterizing the radiation effects of the floating gate itself. The rate dependence, stopping power dependence, SEU susceptibility and applications of floating gate in radiation environment are presented. The ramifications for dosimetry and cell failure are discussed as well as for the long term use aspects of non-volatile memories.

  14. 46 CFR 160.027-3 - Additional requirements for life floats.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 6 2012-10-01 2012-10-01 false Additional requirements for life floats. 160.027-3..., CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Life Floats for Merchant Vessels § 160.027-3 Additional requirements for life floats. (a) Each life float must have a platform...

  15. 46 CFR 160.027-3 - Additional requirements for life floats.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 6 2011-10-01 2011-10-01 false Additional requirements for life floats. 160.027-3..., CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Life Floats for Merchant Vessels § 160.027-3 Additional requirements for life floats. (a) Each life float must have a platform...

  16. [The validation of the effect of correcting spectral background changes based on floating reference method by simulation].

    PubMed

    Wang, Zhu-lou; Zhang, Wan-jie; Li, Chen-xi; Chen, Wen-liang; Xu, Ke-xin

    2015-02-01

    There are some challenges in near-infrared non-invasive blood glucose measurement, such as the low signal to noise ratio of instrument, the unstable measurement conditions, the unpredictable and irregular changes of the measured object, and etc. Therefore, it is difficult to extract the information of blood glucose concentrations from the complicated signals accurately. Reference measurement method is usually considered to be used to eliminate the effect of background changes. But there is no reference substance which changes synchronously with the anylate. After many years of research, our research group has proposed the floating reference method, which is succeeded in eliminating the spectral effects induced by the instrument drifts and the measured object's background variations. But our studies indicate that the reference-point will changes following the changing of measurement location and wavelength. Therefore, the effects of floating reference method should be verified comprehensively. In this paper, keeping things simple, the Monte Carlo simulation employing Intralipid solution with the concentrations of 5% and 10% is performed to verify the effect of floating reference method used into eliminating the consequences of the light source drift. And the light source drift is introduced through varying the incident photon number. The effectiveness of the floating reference method with corresponding reference-points at different wavelengths in eliminating the variations of the light source drift is estimated. The comparison of the prediction abilities of the calibration models with and without using this method shows that the RMSEPs of the method are decreased by about 98.57% (5%Intralipid)and 99.36% (10% Intralipid)for different Intralipid. The results indicate that the floating reference method has obvious effect in eliminating the background changes. PMID:25970930

  17. Digital microfluidics with a magnetically actuated floating liquid marble.

    PubMed

    Khaw, Mei Kum; Ooi, Chin Hong; Mohd-Yasin, Faisal; Vadivelu, Raja; John, James St; Nguyen, Nam-Trung

    2016-06-21

    Controlled actuation of a floating liquid marble, a liquid droplet coated with hydrophobic particles floating on another liquid surface, is a potential digital microfluidics platform for the transport of aqueous solution with minimal volume loss. This paper reports our recent investigation on the magnetic actuation of floating liquid marbles filled with magnetic particles. The magnetic force and frictional force acting on the floating liquid marble determine the horizontal movement of the marble. We varied the magnetic flux density, flux density gradient, concentration of magnetic particles and speed of the marble to elucidate the relationship between the acting forces. We subsequently determined the suitable operating conditions for the actuation and derived the scaling laws for the actuation parameters. PMID:27191398

  18. Preview of Mars Curiosity Parade Float - Duration: 33 seconds.

    NASA Video Gallery

    Jim Green, Director of the Science Mission Directorate Planetary Systems Division at NASA Headquarters, describes the replica of the Mars Curiosity Rover on the second NASA float in Monday's inaugu...

  19. 26. Mechanical float gages used to monitor level of water ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. Mechanical float gages used to monitor level of water in the filtration bed reservoir. - Lake Whitney Water Filtration Plant, Filtration Plant, South side of Armory Street between Edgehill Road & Whitney Avenue, Hamden, New Haven County, CT

  20. Preparation and evaluation of gastroretentive floating tablets of acyclovir.

    PubMed

    Garg, Rajeev; Gupta, G D

    2009-10-01

    The present study performed by preparation and evaluation of floating tablets of Acyclovir as model drug for prolongation of gastric residence time. Floating effervescent tablets were formulated by various materials like hydroxypropyl methylcellulose K 4M, K 15M, psyllium husk, swelling agent as crospovidone and microcrystalline cellulose and gas generating agent like sodium bicarbonate and citric acid and evaluated for floating properties, swelling characteristics and in vitro drug release studies. Floating noneffervescent tablets were prepared by polypropylene foam powder and different matrix forming polymers like HPMC K 4M, Carbopol 934P, xanthan gum and sodium alginate. In vitro drug release studies were performed and drug release kinetics evaluated using the linear regression method was found to follow both the Higuchi and the Korsmeyer and Peppas equation. The drug release mechanism was found fickian type in most of the formulations. PMID:19751200

  1. 50. (no plate) Lens, lens pedestal, mercury float, drawing # ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    50. (no plate) Lens, lens pedestal, mercury float, drawing # 3101, sheet 1 of 2. Approved April 6, 1928. - Block Island Southeast Light, Spring Street & Mohegan Trail at Mohegan Bluffs, New Shoreham, Washington County, RI

  2. 51. (no plate) Lens, lens pedestal, mercury float, shade holder ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    51. (no plate) Lens, lens pedestal, mercury float, shade holder installation, drawing # 3101, sheet 2 of 2. Approved April 6, 1928. - Block Island Southeast Light, Spring Street & Mohegan Trail at Mohegan Bluffs, New Shoreham, Washington County, RI

  3. High voltage switches having one or more floating conductor layers

    SciTech Connect

    Werne, Roger W.; Sampayan, Stephen; Harris, John Richardson

    2015-11-24

    This patent document discloses high voltage switches that include one or more electrically floating conductor layers that are isolated from one another in the dielectric medium between the top and bottom switch electrodes. The presence of the one or more electrically floating conductor layers between the top and bottom switch electrodes allow the dielectric medium between the top and bottom switch electrodes to exhibit a higher breakdown voltage than the breakdown voltage when the one or more electrically floating conductor layers are not present between the top and bottom switch electrodes. This increased breakdown voltage in the presence of one or more electrically floating conductor layers in a dielectric medium enables the switch to supply a higher voltage for various high voltage circuits and electric systems.

  4. 16. EAST ELEVATION OF FLOAT HOUSE AND FISH WATER RELEASE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. EAST ELEVATION OF FLOAT HOUSE AND FISH WATER RELEASE OUTLET. PART OF ENERGY DISSIPATING BAFFLE PIER SYSTEM IS VISIBLE AT LEFT. - Pit 4 Diversion Dam, Pit River west of State Highway 89, Big Bend, Shasta County, CA

  5. Floating Crane YD82 general view. Date taken unknown. Taken ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Floating Crane YD-82 - general view. Date taken unknown. Taken by Pearl Harbor photographer. Crane Division Collection - U.S. Naval Base, Pearl Harbor, Exterior Cranes, Waterfront Crane Track System, Pearl City, Honolulu County, HI

  6. Flow at intermediate depths around Madagascar based on ALACE float trajectories

    NASA Astrophysics Data System (ADS)

    Chapman, P.; Marco, S. F. Di; Davis, R. E.; Coward, A. C.

    2003-07-01

    During 1994-1996, 215 Autonomous Lagrangian Circulation Explorers (ALACE floats) were released at a nominal 900 m depth in the Indian Ocean as part of the World Ocean Circulation Experiment. Of these, 66 entered the region around Madagascar (2-30°S, 35-55°E), generally at a depth of 800-900 m. Floats approaching the island from the east were deflected either northward or southward depending on latitude, with the bifurcation point being near 20°S. Mean southward velocities in the western boundary current were 8.5 cm s -1 during each 25-day observation period, with mean northward velocities 7.7 cm s -1. Speeds past Cape Amber were about 11 cm s -1. These figures are comparable to those obtained from in situ current meter measurements. Floats rounding the island to the north frequently drifted north of the Comores for many months with no discernable pattern, before exiting the region either to the north in the East African Coastal Current and the equatorial current system or to the south via the Mozambique Channel. Flow rates in this region were highly skewed towards low (less than 5 cm s -1) velocities. Floats passing south of Madagascar showed little northward movement into the Mozambique Channel, but tended to move steadily westwards towards the African coast, becoming entrained in the Agulhas Current and its recirculation gyres near 28°S. Similarly, floats released within the southern portion of the Channel all tended to move to the south and west despite occasional entanglement with eddies. Mean flow in the Agulhas region was about 18 cm s -1, with maximum velocities over 25 days of up to about 35 cm s. All flows were extremely variable because of the ubiquity of eddies. In essence, the flow observed near 800 m resembled closely that seen at the surface from TOPEX/POSEIDON altimetry and at 845 m in the OCCAM global model. Temperature data collected by the floats were used to determine when a given float was being acted on by an anticyclonic eddy. Deviations

  7. Comparative evaluation of single and bilayered lamotrigine floating tablets

    PubMed Central

    Lakshmi, PK; Sridhar, M; Shruthi, B

    2013-01-01

    Aim: The purpose of this study was to prepare lamotrigine (LM) bilayered and single layered floating tablets and to compare their release profiles. Materials and Methods: LM floating tablets were prepared by direct compression method. Drug, hydroxy propyl methyl cellulose K4M, lactose monohydrate and polyvinylpyrrolidone K30 constitute controlled release layer components and floating layer components includes polymers and sodium bicarbonate. The prepared tablets were evaluated for physicochemical parameters such as hardness, friability, weight variation, thickness, floating lag time (FLT), floating time, in vitro buoyancy study, in vitro release studies. The drug-polymer interaction was studied by fourier transform infrared and differential scanning calorimetry. Results and Discussion: The FLT of all the formulations were within the prescribed limits (<3 min). When ethyl cellulose was used as floating layer component, tablets showed good buoyancy effect but eroded within 6-8 h. Hence it was replaced with hydroxypropyl cellulose -M hydrophilic polymer, which showed good FLT and floating duration for 16 h. Formulation LFC4 was found to be optimized with dissolution profile of zero order kinetics showing fickian diffusion. A comparative study of bilayered and single layered tablets of LM showed a highest similarity factor of 83.03, difference factor of 2.74 and t-test (P < 0.05) indicates that there is no significant difference between them. Conclusion: Though bilayered tablet possess many advantages, single layered tablet would be economical, cost-effective and reproducible for large scale production in the industry. However, the results of present study demonstrated that the in vitro development of bilayered gastro retentive floating tablets with controlled drug release profile for LM is feasible. PMID:24167788

  8. Numerical simulation of melting ice around a floating by microwaves

    NASA Astrophysics Data System (ADS)

    Lakzian, Esmail; Parsian, Armin; Lakzian, Kazem

    2016-03-01

    In this paper a new method in using microwaves is provided for melting the ice around a floating equipment in a freezing condition in cold regions. The numerical simulation's results for validation are compared with the simple model's experimental data. Using microwave in melting the ice around a floating equipment is caused by lack of the mechanical wear, low energy dissipation factor and acceptable defrosting process speed in small lakes.

  9. UFO in the Left Atrium: How to Capture Metal Debris Floating in the Left Atrium.

    PubMed

    Fassini, Gaetano; Moltrasio, Massimo; Conti, Sergio; Biagioli, Viviana; Tondo, Claudio

    2016-06-01

    Electrophysiology procedures involving left atrium navigation are becoming more frequent, mostly due to the increase of atrial fibrillation ablation. Mapping catheters of different shapes and size as well as dedicated sheaths are mandatory tools for the accomplishment of procedural end point. Therefore, technical issues are expected, usually unrelated to significant risk. However, any accidental intra-atrial device loss of integrity implies a risk of cerebrovascular embolization. The lack of clear evidence on how to manage these events and the need for a quick solution complicate the scenario. We report an empirical solution in the case of debris floating in the left atrium. PMID:26395524

  10. The anatomy of floating shock fitting. [shock waves computation for flow field

    NASA Technical Reports Server (NTRS)

    Salas, M. D.

    1975-01-01

    The floating shock fitting technique is examined. Second-order difference formulas are developed for the computation of discontinuities. A procedure is developed to compute mesh points that are crossed by discontinuities. The technique is applied to the calculation of internal two-dimensional flows with arbitrary number of shock waves and contact surfaces. A new procedure, based on the coalescence of characteristics, is developed to detect the formation of shock waves. Results are presented to validate and demonstrate the versatility of the technique.

  11. An Analysis of the Full-Floating Journal Bearing

    NASA Technical Reports Server (NTRS)

    Shaw, M.C.; Nussdorfer, T.J.

    1947-01-01

    An analysis of the operating characteristics of a full-floating bearing - a bearing in which a floating sleeve is located between the journal and bearing surfaces - is presented together with charts - from which the performance of such bearings may be predicted. Examples are presented to illustrate the use of these charts and a limited number of experiments conducted upon a glass full-floating bearing to verify some results of the analysis are reported. The floating sleeve can operate over a wide range of speeds for a given shaft speed, the exact value depending principally upon the ratio of clearances and upon the ratio of radii of the bearing. Lower operating temperatures at high rotative speeds are to be expected by using a full-floating bearing. This lower operating temperature would be obtained at the expense of the load-carrying capacity of the bearing if, for comparison, the clearances remain the same in both bearings. A full-floating bearing having the same load capacity as a conventional journal bearing may be designed if decreased clearances are allowable.

  12. Fuel primer for float type carburetors

    SciTech Connect

    Scott, W.A.

    1988-04-19

    A fuel primer for float type carburetors having a fuel bowl, the fuel bowl coupled with a fuel inlet, an outlet vent, and a nozzle, the fuel inlet coupled with a fuel source and the nozzle coupled with an intake path, the primer is described comprising: means coupled with the outlet for introducing a pressurized fluid flow in the fuel bowl and means associated with the fuel bowl and ambient air for automatically enabling ambient air flow to enter into the fuel bowl upon start up and for enabling fuel flow to enter into the intake path from the fuel bowl during pressurization of the fluid while preventing the fuel flow from exiting the air flow means during pressurization of the fluid such that air enters an engine through the means associated with the fuel bowl and the engine begins to run and continues to run during start up enabling an operator to move a choke from a closed to an open position for continuous operation of the engine.

  13. Multilateral installation from a floating rig

    SciTech Connect

    1998-07-01

    The Troll Olje gas province is approximately 100 km northwest of Bergen, Norway, in the Norwegian sector of the North Sea at a water depth of approximately 315 to 340 m. Troll Olje is part of the Troll gas field, where Norsk Hydro is responsible for developing two areas with thin oil rims. Before spudding the multilateral well described in this paper, 17 wells had been drilled and completed in the Troll Olje oil province. The multilateral-well concept was introduced in the gas province primarily to increase the drainage area for each well. When producing from two separate laterals, a lower drawdown pressure exists throughout the horizontal section. Therefore, gas coning is less likely to occur, and higher production rates can be sustained for a longer period of time. In addition, cost savings are substantial because of reduced well-construction time for each horizontal reservoir-drainage section and because of the reduced number of completion strings, subsea wellheads, and pipelines required for total field development. The full-length paper details design, development, testing, and installation of the first successful multilateral well installed from a floating rig offshore Norway. The paper gives a synopsis.

  14. Traumatic Floating Clavicle- A case report

    PubMed Central

    Sopu, Alexandra; Green, Connor; Molony, Diarmuid

    2015-01-01

    Introduction: Shoulder injuries after high velocity trauma are common. Clavicle is affected in almost half of these cases. Even so, bipolar dislocation of the clavicle is an unusual injury and seldom reported in the literature. Conservative management is used for almost all the cases and only selected cases will undergo surgical treatment. Case Report: A 52 year old right electrician presented to the emergency department following a fall from a push bicycle. Plain radiographs identified a left first metacarpal (MC) fracture and a bipolar fracture of his right clavicle. Following Fracture Clinic review, significant deformity of the medial clavicle was noted and a CT scan showed anterior dislocation of the medial fragment. Given the degree of deformity and this functional requirement we felt that operative treatment was most appropriate for his unstable medial clavicle fracture dislocation. Conclusion: Surgical treatment of floating clavicle has an important role in the management of fit and active patients. It is important to identify the mechanism of injury and deforming forces in fractures and only after this to plan to neutralise these where appropriate. PMID:27299032

  15. Influence of different types of low substituted hydroxypropyl cellulose on tableting, disintegration, and floating behaviour of floating drug delivery systems

    PubMed Central

    Diós, Péter; Pernecker, Tivadar; Nagy, Sándor; Pál, Szilárd; Dévay, Attila

    2014-01-01

    The object of the present study is to evaluate the effect of application of low-substituted hydroxypropyl cellulose (L-HPC) 11 and B1 as excipients promoting floating in gastroretentive tablets. Directly compressed tablets were formed based on experimental design. Face-centred central composite design was applied with two factors and 3 levels, where amount of sodium alginate (X1) and L-HPC (X2) were the numerical factors. Applied types of L-HPCs and their 1:1 mixture were included in a categorical factor (X3). Studied parameters were floating lag time, floating time, floating force, swelling behaviour of tablets and dissolution of paracetamol, which was used as a model active substance. Due to their physical character, L-HPCs had different water uptake and flowability. Lower flowability and lower water uptake was observed after 60 min at L-HPC 11 compared to L-HPC B1. Shorter floating times were detected at L-HPC 11 and L-HPC mixtures with 0.5% content of sodium alginate, whereas alginate was the only significant factor. Evaluating results of drug release and swelling studies on floating tablets revealed correlation, which can serve to help to understand the mechanism of action of L-HPCs in the field development of gastroretentive dosage forms. PMID:26702261

  16. Free-floating atmospheric pressure ball plasmas

    NASA Astrophysics Data System (ADS)

    Wurden, G. A.; Ticos, C.; Wang, Z.; Wurden, C. J. V.

    2007-11-01

    A long-lived (0.3 second, 10-20 cm diameter) ball plasma floating in the air above a water surface has been formed and studied in the laboratory. A 0.4 - 1 mF capacitor is charged to 4-5 kV, and subsequently discharged (30-60 Amps, 20-50 msec duration) into central copper cathode held fixed just below the surface of a bucket of water (with a weak solution of various salts in distilled water, such as CuSO4 or CuCl2, LiCl or NaCl). An underwater ring anode completes the circuit. A bubble of hot vapor from the water surface rises up in the first few milliseconds, and changes from a mushroom cloud with stalk, to a detached quasi-spherical object, finally evolving into a vortex ring. The plasma consists of ionized water vapor, with positive salts and OH- radicals, as well as molecular species, and it completely excludes nitrogen or oxygen from the rising plasma structure. A fine boundary layer is visible in orange, in contrast to a green ball interior when using Cu/CuSO4, and filamentary structures are visible at late times. Finally, a whisp of smoke ring is observed as a residue. A variety of visible and infrared imaging (both video and still cameras) are used, along with 200-800 nm time & space resolved spectroscopy, to identify features of this laboratory analog to ball lightning. Possible applications include a windowless ball- plasma powered pulsed copper vapor laser operating at 510 nm.

  17. Research on stability of nozzle-floating plate institution

    NASA Astrophysics Data System (ADS)

    Huang, Bin; Tao, Jiayue; Yi, Jiajing; Chen, Shijing

    2016-01-01

    In this paper, air hammer instability of nozzle-floating plate institution in gas lubricated force sensor were studied. Through establishment of the theoretical model for the analysis of the nozzle-floating plate institution stability, combined with air hammer stability judgment theorems, we had some simulation research on the radius of the nozzle, the radius of the pressure chamber, pressure chamber depth, orifice radius and the relationship between air supply pressure and bearing capacity, in order to explore the instability mechanism of nozzle-floating plate institution. For conducting experimental observations for the stability of two groups nozzle-floating plate institution, which have typical structural parameters conducted experimental observations. We set up a special experimental device, verify the correctness of the theoretical study and simulation results. This paper shows that in the nozzle-floating plate institution, increasing the nozzle diameter, reduced pressure chamber radius, reducing the depth of the pressure chamber and increase the supply orifice radius, and other measures is conducive to system stability. Results of this study have important implications for research and design of gas lubricated force sensor.

  18. Preparation and evaluation of gastroretentive floating tablets of Silymarin.

    PubMed

    Garg, Rajeev; Gupta, Ghanshyam Das

    2009-06-01

    The present study performed by preparation and evaluation of floating tablets of Silymarin as model drug for prolongation of gastric residence time. Floating effervescent tablets were formulated by various materials like hydroxypropyl methylcellulose (HPMC) K 4M, K 15M, psyllium husk, swelling agent as crospovidone and microcrystalline cellulose and gas generating agent like sodium bicarbonate and citric acid and evaluated for floating properties, swelling characteristics and in vitro drug release studies. Floating noneffervescent tablets were prepared by polypropylene foam powder and different matrix forming polymers like HPMC K 4M, Carbopol 934P, xanthan gum and sodium alginate. In vitro drug release studies were performed and drug release kinetics evaluated using the linear regression method was found to follow both the Higuchi and the Korsemeyer and Peppas equation. The drug release mechanism was found fickian type in most of the formulations. The developed floating tablets of Silymarin may be used in clinic for prolonged drug release for at least 24 h, thereby improving the bioavailability and patient compliance. PMID:19483331

  19. Test Demonstration of Magnet Power Supply with Floating Capacitor Method

    NASA Astrophysics Data System (ADS)

    Shimogawa, Tetsushi; Morita, Yuichi; Sagawa, Ryu; Kurimoto, Yoshinori; Nakamura, Shu; Miura, Kazuki

    The Japan Proton Accelerator Research Complex (J-PARC) aims at achieving a MW-class proton accelerator facility. We plan to increase the beam power by shortening the repetition period of the Main Ring (MR) from the present period of 2.5 to 1 s in the future. In this scheme, there are serious concerns regarding the main magnets. One involves the increasing output voltage, and the other is related to the power variation of the electric system. We propose an innovative floating capacitor method to produce a high output voltage and suppress the power variation with capacitor energy storage for addressing these concerns. Nevertheless, the driving power supply used with this method needs to establish control of the floating capacitor voltage. We developed and introduced recovery control of the floating capacitor voltage for each accelerator cycle. We also confirmed that the tracking error can be corrected by iterative learning control with the floating capacitor method. In this article, the magnet power supply with the floating capacitor method is described, and test results achieved with the mini model power supply are presented.

  20. The melting of floating ice raises the ocean level

    NASA Astrophysics Data System (ADS)

    Noerdlinger, Peter D.; Brower, Kay R.

    2007-07-01

    It is shown that the melting of ice floating on the ocean will introduce a volume of water about 2.6 per cent greater than that of the originally displaced sea water. The melting of floating ice in a global warming will cause the ocean to rise. If all the extant sea ice and floating shelf ice melted, the global sea level would rise about 4cm. The sliding of grounded ice into the sea, however, produces a mean water level rise in two parts; some of the rise is delayed. The first part, while the ice floats, is equal to the volume of displaced sea water. The second part, equal to 2.6 per cent of the first, is contributed as it melts. These effects result from the difference in volume of equal weights of fresh and salt water. This component of sea rise is apparently unrecognized in the literature to date, although it can be interpreted as a form of halosteric sea level change by regarding the displaced salt water and the meltwater (even before melting) as a unit. Although salinity changes are known to affect sea level, all existing analyses omit our calculated volume change. We present a protocol that can be used to calculate global sea level rise on the basis of the addition of meltwater from grounded and floating ice; of course thermosteric volume change must be added.

  1. Assessment of the nutrient removal effectiveness of floating treatment wetlands applied to urban retention ponds.

    PubMed

    Wang, Chih-Yu; Sample, David J

    2014-05-01

    The application of floating treatment wetlands (FTWs) in point and non-point source pollution control has received much attention recently. Although the potential of this emerging technology is supported by various studies, quantifying FTW performance in urban retention ponds remains elusive due to significant research gaps. Actual urban retention pond water was utilized in this mesocosm study to evaluate phosphorus and nitrogen removal efficiency of FTWs. Multiple treatments were used to investigate the contribution of each component in the FTW system with a seven-day retention time. The four treatments included a control, floating mat, pickerelweed (Pontederia cordata L.), and softstem bulrush (Schoenoplectus tabernaemontani). The water samples collected on Day 0 (initial) and 7 were analyzed for total phosphorus (TP), total particulate phosphorus, orthophosphate, total nitrogen (TN), organic nitrogen, ammonia nitrogen, nitrate-nitrite nitrogen, and chlorophyll-a. Statistical tests were used to evaluate the differences between the four treatments. The effects of temperature on TP and TN removal rates of the FTWs were described by the modified Arrhenius equation. Our results indicated that all three FTW designs, planted and unplanted floating mats, could significantly improve phosphorus and nitrogen removal efficiency (%, E-TP and E-TN) compared to the control treatment during the growing season, i.e., May through August. The E-TP and E-TN was enhanced by 8.2% and 18.2% in the FTW treatments planted with the pickerelweed and softstem bulrush, respectively. Organic matter decomposition was likely to be the primary contributor of nutrient removal by FTWs in urban retention ponds. Such a mechanism is fostered by microbes within the attached biofilms on the floating mats and plant root surfaces. Among the results of the four treatments, the FTWs planted with pickerelweed had the highest E-TP, and behaved similarly with the other two FTW treatments for nitrogen removal

  2. Numerical simulation of a floating buoy in surface waves

    NASA Astrophysics Data System (ADS)

    Altazin, Thomas; Golay, Frédéric; Fraunié, Philippe

    2016-04-01

    A numerical method based on volumic penalization is developed to track a floating body in a two phase flows (air and water). Fast computations on parallel computer are performed thanks to an adaptative mesh refinement following a numerical entropy criterion together with a variable time step depending on the mesh size. Applications concern the motion of a floating buoy in a surface wave field and the induced perturbation of the wave and atmospheric fields by the buoy. Presented cases concern a breaking wave and a second order Stokes wave as initial conditions. Acknowledgements : This research was supported by the Modtercom and CHEF projects of Region PACA, when applications on windage of floating buoys are related to the SUBCORAD LEFE-INSU project.

  3. Research of design challenges and new technologies for floating LNG

    NASA Astrophysics Data System (ADS)

    Lee, Dong-Hyun; Ha, Mun-Keun; Kim, Soo-Young; Shin, Sung-Chul

    2014-06-01

    With the rate of worldwide LNG demand expected to grow faster than that of gas demand, most major oil companies are currently investing their resources to develop floating LNG-FLNG (i.e. LNG FSRU and LNG FPSO). The global Floating LNG (FLNG) market trend will be reviewed based on demand and supply chain relationships. Typical technical issues associated with FLNG design are categorized in terms of global performance evaluation. Although many proven technologies developed through LNG carrier and oil FPSO projects are available for FLNG design, we are still faced with several technical challenges to clear for successful FLNG projects. In this study, some of the challenges encountered during development of the floating LNG facility (i.e. LNG FPSO and FSRU) will be reviewed together with their investigated solution. At the same time, research of new LNG-related technologies such as combined containment system will be presented.

  4. FloatBoost learning and statistical face detection.

    PubMed

    Li, Stan Z; Zhang, ZhenQiu

    2004-09-01

    A novel learning procedure, called FloatBoost, is proposed for learning a boosted classifier for achieving the minimum error rate. FloatBoost learning uses a backtrack mechanism after each iteration of AdaBoost learning to minimize the error rate directly, rather than minimizing an exponential function of the margin as in the traditional AdaBoost algorithms. A second contribution of the paper is a novel statistical model for learning best weak classifiers using a stagewise approximation of the posterior probability. These novel techniques lead to a classifier which requires fewer weak classifiers than AdaBoost yet achieves lower error rates in both training and testing, as demonstrated by extensive experiments. Applied to face detection, the FloatBoost learning method, together with a proposed detector pyramid architecture, leads to the first real-time multiview face detection system reported. PMID:15742888

  5. Seismic monitoring in the oceans by autonomous floats

    NASA Astrophysics Data System (ADS)

    Sukhovich, Alexey; Bonnieux, Sébastien; Hello, Yann; Irisson, Jean-Olivier; Simons, Frederik J.; Nolet, Guust

    2015-08-01

    Our understanding of the internal dynamics of the Earth is largely based on images of seismic velocity variations in the mantle obtained with global tomography. However, our ability to image the mantle is severely hampered by a lack of seismic data collected in marine areas. Here we report observations made under different noise conditions (in the Mediterranean Sea, the Indian and Pacific Oceans) by a submarine floating seismograph, and show that such floats are able to fill the oceanic data gap. Depending on the ambient noise level, the floats can record between 35 and 63% of distant earthquakes with a moment magnitude M>=6.5. Even magnitudes <6.0 can be successfully observed under favourable noise conditions. The serendipitous recording of an earthquake swarm near the Indian Ocean triple junction enabled us to establish a threshold magnitude between 2.7 and 3.4 for local earthquakes in the noisiest of the three environments.

  6. Float-zone processing in a weightless environment

    NASA Technical Reports Server (NTRS)

    Fowle, A. A.; Haggerty, J. S.; Perron, R. R.; Strong, P. F.; Swanson, J. L.

    1976-01-01

    The results were reported of investigations to: (1) test the validity of analyses which set maximum practical diameters for Si crystals that can be processed by the float zone method in a near weightless environment, (2) determine the convective flow patterns induced in a typical float zone, Si melt under conditions perceived to be advantageous to the crystal growth process using flow visualization techniques applied to a dimensionally scaled model of the Si melt, (3) revise the estimates of the economic impact of space produced Si crystal by the float zone method on the U.S. electronics industry, and (4) devise a rational plan for future work related to crystal growth phenomena wherein low gravity conditions available in a space site can be used to maximum benefit to the U.S. electronics industry.

  7. Investigation of field induced trapping on floating gates

    NASA Technical Reports Server (NTRS)

    Gosney, W. M.

    1975-01-01

    The development of a technology for building electrically alterable read only memories (EAROMs) or reprogrammable read only memories (RPROMs) using a single level metal gate p channel MOS process with all conventional processing steps is outlined. Nonvolatile storage of data is achieved by the use of charged floating gate electrodes. The floating gates are charged by avalanche injection of hot electrodes through gate oxide, and discharged by avalanche injection of hot holes through gate oxide. Three extra diffusion and patterning steps are all that is required to convert a standard p channel MOS process into a nonvolatile memory process. For identification, this nonvolatile memory technology was given the descriptive acronym DIFMOS which stands for Dual Injector, Floating gate MOS.

  8. Organic nano-floating-gate transistor memory with metal nanoparticles

    NASA Astrophysics Data System (ADS)

    Van Tho, Luu; Baeg, Kang-Jun; Noh, Yong-Young

    2016-04-01

    Organic non-volatile memory is advanced topics for various soft electronics applications as lightweight, low-cost, flexible, and printable solid-state data storage media. As a key building block, organic field-effect transistors (OFETs) with a nano-floating gate are widely used and promising structures to store digital information stably in a memory cell. Different types of nano-floating-gates and their various synthesis methods have been developed and applied to fabricate nanoparticle-based non-volatile memory devices. In this review, recent advances in the classes of nano-floating-gate OFET memory devices using metal nanoparticles as charge-trapping sites are briefly reviewed. Details of device fabrication, characterization, and operation mechanisms are reported based on recent research activities reported in the literature.

  9. Seismic monitoring in the oceans by autonomous floats.

    PubMed

    Sukhovich, Alexey; Bonnieux, Sébastien; Hello, Yann; Irisson, Jean-Olivier; Simons, Frederik J; Nolet, Guust

    2015-01-01

    Our understanding of the internal dynamics of the Earth is largely based on images of seismic velocity variations in the mantle obtained with global tomography. However, our ability to image the mantle is severely hampered by a lack of seismic data collected in marine areas. Here we report observations made under different noise conditions (in the Mediterranean Sea, the Indian and Pacific Oceans) by a submarine floating seismograph, and show that such floats are able to fill the oceanic data gap. Depending on the ambient noise level, the floats can record between 35 and 63% of distant earthquakes with a moment magnitude M≥6.5. Even magnitudes <6.0 can be successfully observed under favourable noise conditions. The serendipitous recording of an earthquake swarm near the Indian Ocean triple junction enabled us to establish a threshold magnitude between 2.7 and 3.4 for local earthquakes in the noisiest of the three environments. PMID:26289598

  10. Floating cultivation of marine cyanobacteria using coal fly ash.

    PubMed

    Matsumoto, M; Yoshida, E; Takeyama, H; Matsunaga, T

    2000-01-01

    The aim of this study was to develop improved methodologies for bulk culturing of biotechnologically useful marine cyanobacteria in the open ocean. We have investigated the viability of using coal fly ash (CFA) blocks as the support medium in a novel floating culture system for marine micro-algae. The marine cyanobacterium Synechococcus sp. NKBG 040607 was found to adhere to floating CFA blocks in liquid culture medium. Maximum density of attached cells of 2.0 x 10(8) cells/cm2 was achieved using seawater. The marine cyanobacterium Synechococcus sp. NKBG 042902 weakly adhered to floating CFA blocks in BG-11 medium. Increasing the concentration of calcium ion in the culture medium enhanced adherence to CFA blocks. PMID:10849778

  11. Seismic monitoring in the oceans by autonomous floats

    PubMed Central

    Sukhovich, Alexey; Bonnieux, Sébastien; Hello, Yann; Irisson, Jean-Olivier; Simons, Frederik J.; Nolet, Guust

    2015-01-01

    Our understanding of the internal dynamics of the Earth is largely based on images of seismic velocity variations in the mantle obtained with global tomography. However, our ability to image the mantle is severely hampered by a lack of seismic data collected in marine areas. Here we report observations made under different noise conditions (in the Mediterranean Sea, the Indian and Pacific Oceans) by a submarine floating seismograph, and show that such floats are able to fill the oceanic data gap. Depending on the ambient noise level, the floats can record between 35 and 63% of distant earthquakes with a moment magnitude M≥6.5. Even magnitudes <6.0 can be successfully observed under favourable noise conditions. The serendipitous recording of an earthquake swarm near the Indian Ocean triple junction enabled us to establish a threshold magnitude between 2.7 and 3.4 for local earthquakes in the noisiest of the three environments. PMID:26289598

  12. Design, development and evaluation of clopidogrel bisulfate floating tablets

    PubMed Central

    Rao, K. Rama Koteswara; Lakshmi, K. Rajya

    2014-01-01

    Objective: The objective of the present work was to formulate and to characterize a floating drug delivery system for clopidogrel bisulphate to improve bioavailability and to minimize the side effects of the drug such as gastric bleeding and drug resistance development. Materials and Methods: Clopidogrel floating tablets were prepared by direct compression technique by the use of three polymers xanthan gum, hydroxypropyl methylcellulose (HPMC) K15M and HPMC K4M in different concentrations (20%, 25% and 30% w/w). Sodium bicarbonate (15% w/w) and microcrystalline cellulose (30% w/w) were used as gas generating agent and diluent respectively. Studies were carried out on floating behavior and influence of type of polymer on drug release rate. All the formulations were subjected to various quality control and in-vitro dissolution studies in 0.1 N hydrochloric acid (1.2 pH) and corresponding dissolution data were fitted to popular release kinetic equations in order to evaluate release mechanisms and kinetics. Results and Discussion: All the clopidogrel floating formulations followed first order kinetics, Higuchi drug release kinetics with diffusion as the dominant mechanism of drug release. As per Korsmeyer-Peppas equation, the release exponent “n” ranged 0.452-0.654 indicating that drug release from all the formulations was by non-Fickian diffusion mechanism. The drug release rate of clopidogrel was found to be affected by the type and concentration of the polymer used in the formulation (P < 0.05). As the concentration of the polymer was increased, the drug release was found to be retarded. Conclusion: Based on the results, clopidogrel floating tablets prepared by employing xanthan gum at concentration 25% w/w (formulation F2) was the best formulation with desired in-vitro floating time and drug dissolution. PMID:24678458

  13. Liquid mixing driven motions of floating macroscopic objects

    NASA Astrophysics Data System (ADS)

    Su, Ming

    2007-04-01

    Dropping miscible and low-density organic solvents into water generates translational and rotational motions of floating objects including oil droplets, polymer half spheres, and model boats. The moving speed of the boat at different loads and the force produced by solvent drops are measured. In contrast to motions driven by surface tension of monolayer, the liquid mixing driven motion can be dynamically steered without restriction and continued provided the supply is maintained and the amount of water is large enough. Such motions are the result of Marangoni instability in binary liquid-liquid systems with intentionally produced concentration gradients behind the floating objects.

  14. Vegetation, substrate and hydrology in floating marshes in the Mississippi river delta plain wetlands, USA

    USGS Publications Warehouse

    Sasser, C.E.; Gosselink, J.G.; Swenson, E.M.; Swarzenski, C.M.; Leibowitz, N.C.

    1996-01-01

    In the 1940s extensive floating marshes (locally called 'flotant') were reported and mapped in coastal wetlands of the Mississippi River Delta Plain. These floating marshes included large areas of Panicum hemitomon-dominated freshwater marshes, and Spartina patens/Scirpus olneyi brackish marshes. Today these marshes appear to be quite different in extent and type. We describe five floating habitats and one non-floating, quaking habitat based on differences in buoyancy dynamics (timing and degree of floating), substrate characteristics, and dominant vegetation. All floating marshes have low bulk density, organic substrates. Nearly all are fresh marshes. Panicum hemitomon floating marshes presently occur within the general regions that were reported in the 1940's by O'Neil, but are reduced in extent. Some of the former Panicum hemitomon marshes have been replaced by seasonally or variably floating marshes dominated, or co-dominated by Sagittaria lancifolia or Eleocharis baldwinii. ?? 1996 Kluwer Academic Publishers.

  15. Remarks on ``Floating Bodies in Neutral Equilibrium''

    NASA Astrophysics Data System (ADS)

    Finn, Robert

    2009-10-01

    This note offers historical comments on mathematical life in the city of Lwów, and points out that the paper cited in the title contains a solution of Problem 19 in “The Scottish Book”, prepared just prior to World War II in the “Scottish Café” located in that city.

  16. 14 CFR 25.533 - Hull and main float bottom pressures.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hull and main float bottom pressures. 25... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Water Loads § 25.533 Hull and main float bottom pressures. (a) General. The hull and main float structure, including frames and...

  17. 14 CFR 23.533 - Hull and main float bottom pressures.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Hull and main float bottom pressures. 23... Water Loads § 23.533 Hull and main float bottom pressures. (a) General. The hull and main float....00213; K2=hull station weighing factor, in accordance with figure 2 of appendix I of this part;...

  18. 14 CFR 23.533 - Hull and main float bottom pressures.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hull and main float bottom pressures. 23... Water Loads § 23.533 Hull and main float bottom pressures. (a) General. The hull and main float....00213; K2=hull station weighing factor, in accordance with figure 2 of appendix I of this part;...

  19. 14 CFR 25.533 - Hull and main float bottom pressures.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Hull and main float bottom pressures. 25... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Water Loads § 25.533 Hull and main float bottom pressures. (a) General. The hull and main float structure, including frames and...

  20. 14 CFR 25.533 - Hull and main float bottom pressures.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Hull and main float bottom pressures. 25... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Water Loads § 25.533 Hull and main float bottom pressures. (a) General. The hull and main float structure, including frames and...

  1. 14 CFR 23.533 - Hull and main float bottom pressures.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Hull and main float bottom pressures. 23... Water Loads § 23.533 Hull and main float bottom pressures. (a) General. The hull and main float....00213; K2=hull station weighing factor, in accordance with figure 2 of appendix I of this part;...

  2. 14 CFR 23.533 - Hull and main float bottom pressures.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Hull and main float bottom pressures. 23... Water Loads § 23.533 Hull and main float bottom pressures. (a) General. The hull and main float....00213; K2=hull station weighing factor, in accordance with figure 2 of appendix I of this part;...

  3. 46 CFR 180.137 - Stowage of life floats and buoyant apparatus.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Stowage of life floats and buoyant apparatus. 180.137... § 180.137 Stowage of life floats and buoyant apparatus. (a) In addition to meeting § 180.130, each life... other standard specified by the Commandant; (2) Of proper strength for the size of the life float...

  4. 46 CFR 180.137 - Stowage of life floats and buoyant apparatus.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Stowage of life floats and buoyant apparatus. 180.137... § 180.137 Stowage of life floats and buoyant apparatus. (a) In addition to meeting § 180.130, each life... other standard specified by the Commandant; (2) Of proper strength for the size of the life float...

  5. 46 CFR 180.137 - Stowage of life floats and buoyant apparatus.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Stowage of life floats and buoyant apparatus. 180.137... § 180.137 Stowage of life floats and buoyant apparatus. (a) In addition to meeting § 180.130, each life... other standard specified by the Commandant; (2) Of proper strength for the size of the life float...

  6. 46 CFR 117.137 - Stowage of life floats and buoyant apparatus.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Stowage of life floats and buoyant apparatus. 117.137... EQUIPMENT AND ARRANGEMENTS Survival Craft Arrangements and Equipment § 117.137 Stowage of life floats and buoyant apparatus. (a) In addition to meeting § 117.130, each life float and buoyant apparatus must...

  7. 46 CFR 117.137 - Stowage of life floats and buoyant apparatus.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Stowage of life floats and buoyant apparatus. 117.137... EQUIPMENT AND ARRANGEMENTS Survival Craft Arrangements and Equipment § 117.137 Stowage of life floats and buoyant apparatus. (a) In addition to meeting § 117.130, each life float and buoyant apparatus must...

  8. 46 CFR 117.137 - Stowage of life floats and buoyant apparatus.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Stowage of life floats and buoyant apparatus. 117.137... EQUIPMENT AND ARRANGEMENTS Survival Craft Arrangements and Equipment § 117.137 Stowage of life floats and buoyant apparatus. (a) In addition to meeting § 117.130, each life float and buoyant apparatus must...

  9. 46 CFR 180.137 - Stowage of life floats and buoyant apparatus.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Stowage of life floats and buoyant apparatus. 180.137... § 180.137 Stowage of life floats and buoyant apparatus. (a) In addition to meeting § 180.130, each life... other standard specified by the Commandant; (2) Of proper strength for the size of the life float...

  10. 46 CFR 117.137 - Stowage of life floats and buoyant apparatus.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Stowage of life floats and buoyant apparatus. 117.137... EQUIPMENT AND ARRANGEMENTS Survival Craft Arrangements and Equipment § 117.137 Stowage of life floats and buoyant apparatus. (a) In addition to meeting § 117.130, each life float and buoyant apparatus must...

  11. 46 CFR 117.137 - Stowage of life floats and buoyant apparatus.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Stowage of life floats and buoyant apparatus. 117.137... EQUIPMENT AND ARRANGEMENTS Survival Craft Arrangements and Equipment § 117.137 Stowage of life floats and buoyant apparatus. (a) In addition to meeting § 117.130, each life float and buoyant apparatus must...

  12. 33 CFR 147.815 - ExxonMobil Hoover Floating OCS Facility safety zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false ExxonMobil Hoover Floating OCS Facility safety zone. 147.815 Section 147.815 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Floating OCS Facility safety zone. (a) Description. The ExxonMobil Hoover Floating OCS Facility,...

  13. 33 CFR 147.815 - ExxonMobil Hoover Floating OCS Facility safety zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false ExxonMobil Hoover Floating OCS Facility safety zone. 147.815 Section 147.815 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Floating OCS Facility safety zone. (a) Description. The ExxonMobil Hoover Floating OCS Facility,...

  14. 33 CFR 144.01-5 - Location and launching of life floats.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Location and launching of life floats. 144.01-5 Section 144.01-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... Location and launching of life floats. The life floats shall be distributed in accessible locations...

  15. 33 CFR 144.01-5 - Location and launching of life floats.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Location and launching of life floats. 144.01-5 Section 144.01-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... Location and launching of life floats. The life floats shall be distributed in accessible locations...

  16. Tipping Point

    MedlinePlus Videos and Cool Tools

    ... Tipping Point by CPSC Blogger September 22 appliance child Childproofing CPSC danger death electrical fall furniture head ... TV falls with about the same force as child falling from the third story of a building. ...

  17. Hydrodynamic analysis of elastic floating collars in random waves

    NASA Astrophysics Data System (ADS)

    Bai, Xiao-dong; Zhao, Yun-peng; Dong, Guo-hai; Li, Yu-cheng

    2015-06-01

    As the main load-bearing component of fish cages, the floating collar supports the whole cage and undergoes large deformations. In this paper, a mathematical method is developed to study the motions and elastic deformations of elastic floating collars in random waves. The irregular wave is simulated by the random phase method and the statistical approach and Fourier transfer are applied to analyze the elastic response in both time and frequency domains. The governing equations of motions are established by Newton's second law, and the governing equations of deformations are obtained based on curved beam theory and modal superposition method. In order to validate the numerical model of the floating collar attacked by random waves, a series of physical model tests are conducted. Good relationship between numerical simulation and experimental observations is obtained. The numerical results indicate that the transfer function of out-of-plane and in-plane deformations increase with the increasing of wave frequency. In the frequency range between 0.6 Hz and 1.1 Hz, a linear relationship exists between the wave elevations and the deformations. The average phase difference between the wave elevation and out-of-plane deformation is 60° with waves leading and the phase between the wave elevation and in-plane deformation is 10° with waves lagging. In addition, the effect of fish net on the elastic response is analyzed. The results suggest that the deformation of the floating collar with fish net is a little larger than that without net.

  18. Vibrations of a floating beam on marine waves

    SciTech Connect

    Sabaneev, Valentin S.; Tovstik, Petr E.; Tovstik, Tatiana M.; Shekhovtsov, Alexei S.

    2015-03-10

    Vertical vibrations of a floating pipe-concrete beam caused by a harmonic waves excitation are studied. The apparent additional mass of water, resisting force and the velocity of towing are considered. The vibration amplitude and the maximum deformations of concrete, caused by these fluctuations, are calculated.

  19. 27. Detail view of mechanical float gages used to monitor ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    27. Detail view of mechanical float gages used to monitor level of water in the filtration bed reservoir. Gage on left measures water head, gage on right monitors filtration rate. - Lake Whitney Water Filtration Plant, Filtration Plant, South side of Armory Street between Edgehill Road & Whitney Avenue, Hamden, New Haven County, CT

  20. 33 CFR 143.120 - Floating OCS facilities.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) OUTER CONTINENTAL SHELF ACTIVITIES DESIGN AND EQUIPMENT OCS Facilities § 143.120 Floating OCS facilities... CFR part 107 which relate to the facility. All plans and information must be submitted according to... (Marine Engineering) and J (Electrical Engineering) of 46 CFR chapter I and 46 CFR part 108 (Design...

  1. 33 CFR 144.01-15 - Alternates for life floats.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Alternates for life floats. 144.01-15 Section 144.01-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-15...

  2. Topside facilities for floating production systems require new engineering thinking

    SciTech Connect

    Burn, A.J.; Graaf, G.

    1983-05-01

    Since the oil industry moved offshore, great emphasis has been placed on the need to reduce space and weight requirements of topside facilities. For successful design of floating production systems, weight consciousness assumes an even higher level of importance, necessitating systematic attention to detail even at the feasibility study stage of a project.

  3. 40 CFR 63.1063 - Floating roof requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... requirements—(1) Rim seals. (i) Internal floating roof. An IFR shall be equipped with one of the seal... opening except those for automatic bleeder vents (vacuum breaker vents) and rim space vents shall have its... vents (vacuum breaker vents), rim space vents, leg sleeves, and deck drains shall be equipped with...

  4. 40 CFR 65.44 - External floating roof (EFR).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... breaker vents) and rim space vents, each opening in the noncontact external floating roof shall provide a... they are closed. (iii) Except for automatic bleeder vents, rim space vents, roof drains, and leg... and rim space vents shall be equipped with a gasket. (v) Each roof drain that empties into the...

  5. 40 CFR 63.1063 - Floating roof requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... requirements—(1) Rim seals. (i) Internal floating roof. An IFR shall be equipped with one of the seal... opening except those for automatic bleeder vents (vacuum breaker vents) and rim space vents shall have its... vents (vacuum breaker vents), rim space vents, leg sleeves, and deck drains shall be equipped with...

  6. 40 CFR 63.1063 - Floating roof requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... requirements—(1) Rim seals. (i) Internal floating roof. An IFR shall be equipped with one of the seal... opening except those for automatic bleeder vents (vacuum breaker vents) and rim space vents shall have its... vents (vacuum breaker vents), rim space vents, leg sleeves, and deck drains shall be equipped with...

  7. 40 CFR 65.44 - External floating roof (EFR).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... breaker vents) and rim space vents, each opening in the noncontact external floating roof shall provide a... they are closed. (iii) Except for automatic bleeder vents, rim space vents, roof drains, and leg... and rim space vents shall be equipped with a gasket. (v) Each roof drain that empties into the...

  8. 40 CFR 65.44 - External floating roof (EFR).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... breaker vents) and rim space vents, each opening in the noncontact external floating roof shall provide a... they are closed. (iii) Except for automatic bleeder vents, rim space vents, roof drains, and leg... and rim space vents shall be equipped with a gasket. (v) Each roof drain that empties into the...

  9. Free-floating dual-arm robots for space assembly

    NASA Technical Reports Server (NTRS)

    Agrawal, Sunil Kumar; Chen, M. Y.

    1994-01-01

    Freely moving systems in space conserve linear and angular momentum. As moving systems collide, the velocities get altered due to transfer of momentum. The development of strategies for assembly in a free-floating work environment requires a good understanding of primitives such as self motion of the robot, propulsion of the robot due to onboard thrusters, docking of the robot, retrieval of an object from a collection of objects, and release of an object in an object pool. The analytics of such assemblies involve not only kinematics and rigid body dynamics but also collision and impact dynamics of multibody systems. In an effort to understand such assemblies in zero gravity space environment, we are currently developing at Ohio University a free-floating assembly facility with a dual-arm planar robot equipped with thrusters, a free-floating material table, and a free-floating assembly table. The objective is to pick up workpieces from the material table and combine them into prespecified assemblies. This paper presents analytical models of assembly primitives and strategies for overall assembly. A computer simulation of an assembly is developed using the analytical models. The experiment facility will be used to verify the theoretical predictions.

  10. Design And Testing of The Floating Potential Probe For ISS

    NASA Technical Reports Server (NTRS)

    Hillard, G. Barry; Ferguson, Dale C.

    2001-01-01

    Flight 4A was an especially critical mission for the International Space Station (ISS). For the first time, the high voltage solar arrays generated significant amounts of power and long predicted environmental interactions (high negative floating potential and concomitant dielectric charging) became serious concerns. Furthermore, the same flight saw the Plasma Contacting Unit (PCU) deployed and put into operation to mitigate and control these effects. The ISS program office has recognized the critical need to verify, by direct measurement, that ISS does not charge to unacceptable levels. A Floating Potential Probe (FPP) was therefore deployed on ISS to measure ISS floating potential relative to the surrounding plasma and to measure relevant plasma parameters. The primary objective of FPP is to verify that ISS floating potential does not exceed the specified level of 40 volts with respect to the ambient. Since it is expected that in normal operations the PCU will maintain ISS within this specification, it is equivalent to say that the objective of FPP is to monitor the functionality of the PCU. In this paper, we report on the design and testing of the ISS FPP. In a separate paper, the operations and results obtained so far by the FPP will be presented.

  11. 33 CFR 144.01-10 - Equipment for life floats.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... type constructed in accordance with 46 CFR Subpart 161.010, except a water light constructed in accordance with former 46 CFR Subpart 161.001 that was installed before January 1, 1972, may be retained in... attached to the life float by a 12-thread manila or equivalent synthetic lanyard not less than 2 meters...

  12. 33 CFR 144.01-10 - Equipment for life floats.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... type constructed in accordance with 46 CFR Subpart 161.010, except a water light constructed in accordance with former 46 CFR Subpart 161.001 that was installed before January 1, 1972, may be retained in... attached to the life float by a 12-thread manila or equivalent synthetic lanyard not less than 2 meters...

  13. 33 CFR 144.01-10 - Equipment for life floats.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... type constructed in accordance with 46 CFR Subpart 161.010, except a water light constructed in accordance with former 46 CFR Subpart 161.001 that was installed before January 1, 1972, may be retained in... attached to the life float by a 12-thread manila or equivalent synthetic lanyard not less than 2 meters...

  14. 40 CFR 63.1043 - Standards-Separator floating roof.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... floating roof shall be equipped with two continuous seals, one above the other, between the wall of the... seal, as defined in § 63.1041 of this subpart. The total area of the gaps between the separator wall and the primary seal shall not exceed 67 square centimeters (cm2) per meter of separator...

  15. 40 CFR 63.1043 - Standards-Separator floating roof.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... floating roof shall be equipped with two continuous seals, one above the other, between the wall of the... seal, as defined in § 63.1041 of this subpart. The total area of the gaps between the separator wall and the primary seal shall not exceed 67 square centimeters (cm2) per meter of separator...

  16. 40 CFR 63.1043 - Standards-Separator floating roof.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... floating roof shall be equipped with two continuous seals, one above the other, between the wall of the... seal, as defined in § 63.1041 of this subpart. The total area of the gaps between the separator wall and the primary seal shall not exceed 67 square centimeters (cm2) per meter of separator...

  17. 33 CFR 143.120 - Floating OCS facilities.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CFR part 107 which relate to the facility. All plans and information must be submitted according to... (Marine Engineering) and J (Electrical Engineering) of 46 CFR chapter I and 46 CFR part 108 (Design and... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Floating OCS facilities....

  18. Floating three-dimensional display viewable from 360 degrees

    NASA Astrophysics Data System (ADS)

    Miyazaki, Daisuke; Akasaka, Nobuhiro; Okoda, Kenta; Maeda, Yuki; Mukai, Takaaki

    2012-03-01

    The aim of this research is to develop a full-parallax auto-stereoscopic display system, which can generate a floating three-dimensional (3-D) image viewable from a surrounding area. A 3-D display method based on the combination of integral imaging, 360-degree scanning with a rotating mirror, and imaging in the air with a concave mirror is proposed. A scanning system is composed of a hemisphere concave mirror and a mirror scanner, which is located around the center of the concave mirror. By putting an image generated by an integral imaging system into the scanning system, a floating stereoscopic image can be formed around the center of the concave mirror. When the mirror scanner rotates and the image on the integral imaging system is switched in accordance with mirror angle, each directional image can be observed from each viewing angle. The feasibility of the proposed method was examined by preliminary experiments. The abilities of generation of a floating full-parallax image and a floating auto-stereoscopic image with 360-degree viewing angle are demonstrated.

  19. Treatment of Aquaculture Wastewater Using Floating Vegetated Mats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Methods are needed for treating aquaculture wastewater. The goal is to improve wastewater quality sufficiently for it to be recycled to production ponds. One potential method for improving aquaculture wastewater is to use floating vegetation in treatment tanks. Alternatively, potential exists for ...

  20. Experiment study of the motion of the floating offshore turbine

    NASA Astrophysics Data System (ADS)

    Chuang, Tzu-Ching; Hsu, Wen-Yang; Yang, Ray-Yeng; Chen, Yang-Yi

    2016-04-01

    Recently the wind industry moved to offshore areas. The floating wind turbine combined the platform and the mooring system. This research focuses on studying the motion of the floating offshore turbine with a mooring system. The platform, which was developed by the Ship and Ocean Industries R&D Center, had been test in a wave-wind flume in the Tainan Hydraulics Laboratory by using a 1:50 Froude scaling model. In the experiment, the floating offshore turbine was placed in a water flume and exposed to periodic waves at frequencies ranging from 0.22 rad/s - 0.875 rad/s, the wave amplitude is about 2.5 meter, and with the different pretension of the mooring lines. The experiment includes the measurement of damping coefficient from the free decay test and the dynamic response in a sea state. This research compares the motion of the floating offshore turbine with the different pretension of the mooring lines, and the model provides comprehensive data for the operational, design, and survival seas states, as well as the calibration and improvement of the existing design and performance of numerical models.

  1. The sheath effect on the floating harmonic method

    SciTech Connect

    Lee, Jaewon; Kim, Kyung-Hyun; Chung, Chin-Wook

    2015-12-15

    The floating harmonic method biases sinusoidal voltage to a probe sheath, and as its response, harmonic currents can be obtained. These currents can be used to determine the plasma parameters. However, different shapes of probes have different shapes of sheaths that can affect the diagnostic results. However, no research has been done on the sheath effect on the floating harmonic method. Therefore, we investigate the effect of the sheath during floating harmonic diagnostics by comparing cylindrical and planar probes. While the sinusoidal voltages were applied to a probe, because the sheath oscillated, the time variant ion current and their harmonic currents were added to the electron harmonic currents. In the floating harmonic method, the harmonic currents are composed of only the electron harmonic currents. Therefore, the ion harmonic currents affect the diagnostic results. In particular, the electron temperature obtained by the small probe tip was higher than that of the large probe tip. This effect was exacerbated when the ratio of the probe tip radius to the sheath length was smaller.

  2. Problematic Issue for Students: Does It Sink or Float?

    ERIC Educational Resources Information Center

    Ünal, Suat; Costu, Bayram

    2005-01-01

    The aim of this study is to investigate grade-eight students' conceptions of sinking and floating. Firstly, semi-structured interviews were conducted with 12 students to determine students' difficulties and to develop a multiple-choice diagnostic test. In designing the content of the interview questions, grade-eight science curriculum, research on…

  3. 10. LOOKING DOWN ON TUG AND CAR FLOAT BEING UNLOADED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. LOOKING DOWN ON TUG AND CAR FLOAT BEING UNLOADED AT BRIDGE NO. 11 SHOWING TRACK, LOCKING MECHANISMS, AND MOORING WINCH IN FOREGROUND. LOOKING EAST. - Greenville Yard, Transfer Bridge System, Port of New York/New Jersey, Upper New York Bay, Jersey City, Hudson County, NJ

  4. Children's Typically-Perceived-Situations of Floating and Sinking

    ERIC Educational Resources Information Center

    Joung, Yong Jae

    2009-01-01

    The purpose of this study is to explore children's typically-perceived-situations (TPS) of "floating" and "sinking". TPS refers to the situation rising spontaneously in an individual's mind when they first think of a phenomenon or concept. Data were collected from 148 Year 5 Korean children. As a result of analysing the data according to three…

  5. CMOS Active-Pixel Image Sensor With Simple Floating Gates

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R.; Nakamura, Junichi; Kemeny, Sabrina E.

    1996-01-01

    Experimental complementary metal-oxide/semiconductor (CMOS) active-pixel image sensor integrated circuit features simple floating-gate structure, with metal-oxide/semiconductor field-effect transistor (MOSFET) as active circuit element in each pixel. Provides flexibility of readout modes, no kTC noise, and relatively simple structure suitable for high-density arrays. Features desirable for "smart sensor" applications.

  6. 14 CFR 23.535 - Auxiliary float loads.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... are as follows: EC28SE91.011 where— P=mass density of water (slugs/ft.3) V=volume of float (ft.3); CX... AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Structure Water Loads § 23... paragraphs (b) through (e) of this section, the prescribed water loads may be distributed over the...

  7. 14 CFR 23.535 - Auxiliary float loads.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... are as follows: EC28SE91.011 where— P=mass density of water (slugs/ft.3) V=volume of float (ft.3); CX... AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Structure Water Loads § 23... paragraphs (b) through (e) of this section, the prescribed water loads may be distributed over the...

  8. 14 CFR 23.535 - Auxiliary float loads.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... are as follows: EC28SE91.011 where— P=mass density of water (slugs/ft.3) V=volume of float (ft.3); CX... AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Structure Water Loads § 23... paragraphs (b) through (e) of this section, the prescribed water loads may be distributed over the...

  9. 14 CFR 23.535 - Auxiliary float loads.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... are as follows: EC28SE91.011 where— P=mass density of water (slugs/ft.3) V=volume of float (ft.3); CX... AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Structure Water Loads § 23... paragraphs (b) through (e) of this section, the prescribed water loads may be distributed over the...

  10. Free-floating collagen fibers in interstitial mycosis fungoides.

    PubMed

    Ferrara, Gerardo; Crisman, Giuliana; Zalaudek, Iris; Argenziano, Giuseppe; Stefanato, Catherine M

    2010-06-01

    We present a case of interstitial mycosis fungoides showing pseudodovascular clefts with "free-floating" collagen fibers surrounded by neoplastic T lymphocytes. Such a finding further expands the histopathologic spectrum of mycosis fungoides and could be taken into account in its differential diagnosis from granuloma annulare, inflammatory morphea, and interstitial granulomatous drug reaction. PMID:20145533

  11. Estimating the center of mass of a free-floating body in microgravity.

    PubMed

    Lejeune, L; Casellato, C; Pattyn, N; Neyt, X; Migeotte, P-F

    2013-01-01

    This paper addresses the issue of estimating the position of the center of mass (CoM) of a free-floating object of unknown mass distribution in microgravity using a stereoscopic imaging system. The method presented here is applied to an object of known mass distribution for validation purposes. In the context of a study of 3-dimensional ballistocardiography in microgravity, and the elaboration of a physical model of the cardiovascular adaptation to weightlessness, the hypothesis that the fluid shift towards the head of astronauts induces a significant shift of their CoM needs to be tested. The experiments were conducted during the 57th parabolic flight campaign of the European Space Agency (ESA). At the beginning of the microgravity phase, the object was given an initial translational and rotational velocity. A 3D point cloud corresponding to the object was then generated, to which a motion-based method inspired by rigid body physics was applied. Through simulations, the effects of the centroid-to-CoM distance and the number of frames of the sequence are investigated. In experimental conditions, considering the important residual accelerations of the airplane during the microgravity phases, CoM estimation errors (16 to 76 mm) were consistent with simulations. Overall, our results suggest that the method has a good potential for its later generalization to a free-floating human body in a weightless environment. PMID:24110838

  12. Investigated performance of uncooled tantalum-doped VOx floating-type microbolometers

    NASA Astrophysics Data System (ADS)

    Lee, Hsin-Ying; Wu, Chia-Ling; Kao, Ching-Hua; Lee, Ching-Ting; Tang, Shiang-Feng; Lin, Wen-Jen; Chen, Hsin-Chang; Lin, Jia-Ching

    2015-11-01

    Various tantalum (Ta)-doped vanadium oxide (VOx:Ta) films with various Ta doping contents were deposited on the Si substrates as the sensitive layer of the floating-type microbolometers using a magnetron radio frequency (RF) co-sputtering system. The vanadium (V) target and the tantalum pentoxide (Ta2O5) target were used to deposit the VOx:Ta films. To improve the microbolometer responsivity by effectively reducing the thermal loss from the Si substrates, the floating-type microbolometers were fabricated using bulk micromachining technique. From the X-ray photoelectron spectroscopy (XPS) spectra, except the V2O5 and V6O13, the lower oxygen state of VOx films, such as VO2 and V2O3, were also obtained by doping Ta into the VOx films. Consequently, compared with the VO2 microbolometers, the VOx:Ta microbolometers could operate at a higher operating temperature range. The temperature coefficient of resistance (TCR) and the resistivity of the VOx:Ta (Ta content of 7.63%) films measured by four point probe measurement in heating system were -3.47%/K and 9.32 Ω-cm, respectively. The Ta-doped VOx microbolometer revealed a higher responsivity of 341 kV/W compared with 106 kV/W of the undoped VOx microbolometer.

  13. Low-frequency vibration control of floating slab tracks using dynamic vibration absorbers

    NASA Astrophysics Data System (ADS)

    Zhu, Shengyang; Yang, Jizhong; Yan, Hua; Zhang, Longqing; Cai, Chengbiao

    2015-09-01

    This study aims to effectively and robustly suppress the low-frequency vibrations of floating slab tracks (FSTs) using dynamic vibration absorbers (DVAs). First, the optimal locations where the DVAs are attached are determined by modal analysis with a finite element model of the FST. Further, by identifying the equivalent mass of the concerned modes, the optimal stiffness and damping coefficient of each DVA are obtained to minimise the resonant vibration amplitudes based on fixed-point theory. Finally, a three-dimensional coupled dynamic model of a metro vehicle and the FST with the DVAs is developed based on the nonlinear Hertzian contact theory and the modified Kalker linear creep theory. The track irregularities are included and generated by means of a time-frequency transformation technique. The effect of the DVAs on the vibration absorption of the FST subjected to the vehicle dynamic loads is evaluated with the help of the insertion loss in one-third octave frequency bands. The sensitivities of the mass ratio of DVAs and the damping ratio of steel-springs under the floating slab are discussed as well, which provided engineers with the DVA's adjustable room for vibration mitigation. The numerical results show that the proposed DVAs could effectively suppress low-frequency vibrations of the FST when tuned correctly and attached properly. The insertion loss due to the attachment of DVAs increases as the mass ratio increases, whereas it decreases with the increase in the damping ratio of steel-springs.

  14. Formulation and evaluation of floating matrix tablet of stavudine

    PubMed Central

    Prajapati, Pankaj H; Nakum, Vijay V; Patel, Chhagan N

    2012-01-01

    Background/Aim: The purpose of the study was to prolong the gastric residence time of stavudine by designing its floating tablets and to study the influence of different polymers on its release rate. Materials and Methods: The floating mix matrix tablets of stavudine were prepared by melt granulation method. Beeswax was used as hydrophobic meltable material. Hydroxypropyl methylcellulose (HPMC), sodium bicarbonate, and ethyl cellulose were used as matrixing agent, gas generating agent, and floating enhancer, respectively. The prepared tablets were evaluated for physicochemical parameters such as hardness, weight variation, friability, floating properties (floating lag time, total floating time), drug content, stability study, and in vitro drug release. The drug- polymer interaction was studied by Differential Scanning Calorimetry (DSC) thermal analysis and Fourier transform infared (FT-IR). Results: The floating lag time of all the formulations was within the prescribed limit (<3 min). All the formulations showed good matrix integrity and retarded the release of drug for 12 h except the formulation F5.The concentration of beeswax (X1), HPMC K4M (X2), and ethyl cellulose (X3) were selected as independent variables and drug release values at 1 (Q1), at 6 (Q6) and at 12 h (Q12) as dependent variables. Formulation F7 was selected as an optimum formulation as it showed more similarity in dissolution profile with theoretical profile (similarity factor, f2 = 70.91). The dissolution of batch F7 can be described by zero-order kinetics (R2 =0.9936) with anomalous (non-Fickian) diffusion as the release mechanism (n=0.545). There was no difference observed in release profile after temperature sensitivity study at 40°C/75% relative humidity (RH) for 1 month. Conclusion: It can be concluded from this study that the combined mix matrix system containing hydrophobic and hydrophilic polymer minimized the burst release of drug from the tablet and achieved a drug release by zero

  15. Gigaflop (billion floating point operations per second) performance for computational electromagnetics

    NASA Technical Reports Server (NTRS)

    Shankar, V.; Rowell, C.; Hall, W. F.; Mohammadian, A. H.; Schuh, M.; Taylor, K.

    1992-01-01

    Accurate and rapid evaluation of radar signature for alternative aircraft/store configurations would be of substantial benefit in the evolution of integrated designs that meet radar cross-section (RCS) requirements across the threat spectrum. Finite-volume time domain methods offer the possibility of modeling the whole aircraft, including penetrable regions and stores, at longer wavelengths on today's gigaflop supercomputers and at typical airborne radar wavelengths on the teraflop computers of tomorrow. A structured-grid finite-volume time domain computational fluid dynamics (CFD)-based RCS code has been developed at the Rockwell Science Center, and this code incorporates modeling techniques for general radar absorbing materials and structures. Using this work as a base, the goal of the CFD-based CEM effort is to define, implement and evaluate various code development issues suitable for rapid prototype signature prediction.

  16. Experimental Wave Tank Test for Reference Model 3 Floating-Point Absorber Wave Energy Converter Project

    SciTech Connect

    Yu, Y. H.; Lawson, M.; Li, Y.; Previsic, M.; Epler, J.; Lou, J.

    2015-01-01

    The U.S. Department of Energy established a reference model project to benchmark a set of marine and hydrokinetic technologies including current (tidal, open-ocean, and river) turbines and wave energy converters. The objectives of the project were to first evaluate the status of these technologies and their readiness for commercial applications. Second, to evaluate the potential cost of energy and identify cost-reduction pathways and areas where additional research could be best applied to accelerate technology development to market readiness.

  17. Ability of floating platforms and tankers to operate in the Hibernia environment

    SciTech Connect

    Mcintyre, N.F.

    1981-01-01

    The ability of floating platforms and tankers to operate in the Hibernia environment is discussed. The basic environmental difference between the fixed and floating concept is that the floating systems are unable to withstand impact from heavy ice floes or large icebergs. Therefore, they are designed to utilize safe, reliable quick-disconnect systems, which permit them to evacuate the area when encroaching ice presents a potential hazard. Floating production systems being considered for Hibernia involve ship-type vessels, conventional semisubmersibles, and some form of floating storage and loading facility.

  18. Analysis of an Anomaly: The Increase in Time Float following Consumption

    PubMed Central

    Qi, Jianxun; Su, Zhixiong

    2014-01-01

    One fundamental axiom for project plan and schedule relates to the notion that time float will be reduced following its consumption. However, an anomalous scenario can emerge in which an activity's time float increases following its consumption. By exploring the associations between time float and paths in activity networks, we (a) reveal the conditions under which the anomaly occurs and (b) summarize laws related to total float. An activity's total float increases in parallel with its duration prolongation within a given boundary but remains constant or decreases in parallel with a prolongation outside the boundary. Furthermore, whereas a prolongation of an activity's duration in excess of classic total float does not delay project completion time, a lag of its start time to a degree slightly greater than the total float does. This analysis reveals different types of total float that correspond to different ways of usage. From this, we offer definitions for translation total float and prolongation total float that deviate from traditional conventions regarding the uniqueness of total float. PMID:25250376

  19. Characterization of cement float buoyancy in the stalked barnacle Dosima fascicularis (Crustacea, Cirripedia)

    PubMed Central

    Zheden, Vanessa; Kovalev, Alexander; Gorb, Stanislav N.; Klepal, Waltraud

    2015-01-01

    Dosima fascicularis is the only barnacle which can drift autonomously at the water surface with a foam-like cement float. The cement secreted by the animal contains numerous gas-filled cells of different size. When several individuals share one float, their size and not their number is crucial for the production of both volume and mass of the float. The gas content within the cells of the foam gives positive static buoyancy to the whole float. The volume of the float, the gas volume and the positive static buoyancy are positively correlated. The density of the cement float without gas is greater than that of seawater. This study shows that the secreted cement consists of more than 90% water and the gas volume is on average 18.5%. Our experiments demonstrate that the intact foam-like cement float is sealed to the surrounding water. PMID:25657839

  20. Characterization of cement float buoyancy in the stalked barnacle Dosima fascicularis (Crustacea, Cirripedia).

    PubMed

    Zheden, Vanessa; Kovalev, Alexander; Gorb, Stanislav N; Klepal, Waltraud

    2015-02-01

    Dosima fascicularis is the only barnacle which can drift autonomously at the water surface with a foam-like cement float. The cement secreted by the animal contains numerous gas-filled cells of different size. When several individuals share one float, their size and not their number is crucial for the production of both volume and mass of the float. The gas content within the cells of the foam gives positive static buoyancy to the whole float. The volume of the float, the gas volume and the positive static buoyancy are positively correlated. The density of the cement float without gas is greater than that of seawater. This study shows that the secreted cement consists of more than 90% water and the gas volume is on average 18.5%. Our experiments demonstrate that the intact foam-like cement float is sealed to the surrounding water. PMID:25657839

  1. Designs and applications for floating-hydro power systems in small streams

    SciTech Connect

    Rehder, J.B.

    1983-01-01

    The project focuses on an appropriate technology for small-scale hydro power: floating waterwheels and turbines. For background, relic and existing systems such as early floating mills, traditional Amish waterwheels, and micro-hydro systems are examined. In the design phase of the project, new designs for Floating Hydro Power Systems include: an analysis of floatation materials and systems; a floating undershot waterwheel design; a floating cylinder (fiberglass storage tank) design; a submerged tube design; and a design for a floating platform with submerged propellers. Finally, in the applications phase, stream flow data from East Tennessee streams are used in a discussion of the potential applications of floating hydro power systems in small streams.

  2. Analyses and thought on countermeasures for the family formation trend among floating population in Wuhan city.

    PubMed

    Chen, X; Sun, L

    1997-01-01

    The familized floating population in China consists of families formed from blood kinship networks of floating population. This study examines the size of the familized floating population in Wuhan City in 1995 and the negative impacts for urban management, supplies, family planning, education, and employment. Floating population families are formed due to the presence of rural and urban differences, the desire for income, and a goal of permanent urban residence with family stability and steady economic gains. Data were obtained from a 1% sample survey among the floating population who lived in rented, borrowed, or self-built houses or apartments for over 6 months. 69.2% of the floating population, or 335,000 people, were familized floating population. 55.01% of the familized floating population were women, and 60.41% of the laborers were women. 33.50% of the women who "should" be employed were not. 50% of the women in some districts were unemployed. 30.61% were children under 14 years of age. The dependency burden for the employed floating population was greater than for the urban employed population. The birth rate among the familized floating population was 44.60%. 89.59% of women aged older than 15 years in the familized floating population were of childbearing age. Most had a low level of education. The floating population creates the need for educating 15,000 new students every year; this requires construction of 10 new schools every year. The floating population increases the need to produce more electricity, clothing, food, houses, and other services or facilities. The floating population brings norms about a higher family size, which challenges urban residents' beliefs and impedes smooth implementation of the family planning policy. Management needs to regulate population flow, reduce consumption, and control family formation and childbearing. Management needs to increase mobility costs. PMID:12320985

  3. Redox dynamics in multicomponent, iron-bearing silicate melts and glasses: Application to the float-glass processing of high-temperature silicate glassmelts

    NASA Astrophysics Data System (ADS)

    Cook, Glen Bennett

    Processing high-strain-point glasses by the float process is challenged by the relative thermochemical properties of glassmelts and the liquid-metal float medium. As the chemical reaction between the glassmelt and the float metal involves dynamic reduction of the glassmelt, this research has examined the constraints on high-temperature float processing of glassmelts by combining metal-alloy/oxide reaction thermodynamics and Wagnerian kinetic models for redox reactions in silicate melts. The dynamic response of Fe-bearing, p-type (polaronic) semiconducting amorphous silicates to a chemical potential gradient of oxygen has been shown to be rate-limited by the chemical diffusion of network-modifying cations. The persistence of this mechanism to very low Fe concentrations in Fe-doped magnesium aluminosilicate glasses was proven with Rutherford backscattering spectroscopy. Three glasses, with 0.1, 0.5, and 1.25 mol. % FeO were reacted with air at temperatures from 710-845sp°C. For all compositions and temperatures, oxidation was dominated by network modifier diffusion; an activation energy of 475 kJ*molsp{-1} characterized the process. Chemical dynamics in a high-temperature float environment were characterized on liquid-liquid reaction couples between two low-Fe sodium-aluminoborosilicate (NABS) glassmelts (0.01 and 0.08 mol. % FeO) and Au-30Sn and Au-28Ge (atomic basis) alloys. Experiments were performed in the temperature range 1250-1450sp°C for 30 min; wavelength-dispersive and Rutherford backscattering spectroscopies were employed. These exothermic liquid-metal alloys display large negative deviations from ideal solution behavior, with significantly depressed chemical activities. Diffusion of Sn or Ge in the NABS glassmelts (depth and concentration) was limited at all temperatures to levels comparable to conventional soda-lime (NCS) float glass (˜2 min on pure Sn at 1100sp°C). Incorporation of Sn or Ge was reduced significantly in the higher-Fe-content NABS

  4. High-sensitivity organic phototransistors prepared by floating film transfer method

    NASA Astrophysics Data System (ADS)

    Bhargava, Kshitij; Singh, Vipul

    2016-09-01

    In this report, the performance characteristics of organic phototransistors (OPTs) prepared by the floating film transfer method (FTM) and spin coating (SC) technique are compared. The FTM OPT shows a 2-order-higher photosensitivity under an electrically induced off-state as compared with the SC OPT. Furthermore, the FTM OPT shows improved gate voltage tunabilities of photosensitivity and responsivity as compared with the SC OPT. These observed results are explained on the basis of the improved thin film morphology of the active poly(3-hexylthiophene-2,5-diyl) (P3HT) layer in the FTM OPT, pointing towards the significance of thin film processing conditions in obtaining high-sensitivity OPTs.

  5. Development of air touch interface for floating 3D image in the air

    NASA Astrophysics Data System (ADS)

    Fukuda, Hiroyuki; Morimoto, Hiroyuki; Sakamoto, Kunio

    2007-09-01

    We developed a prototype virtual air touch interface system for interaction in the virtual 3D space. The spatial imaging display system provides the observer virtual 3D objects. These 3D images are floating in the air and one can directly touch objects or virtual images. To take mutual action we need to prepare the interface system which can recognize that the user moves his hand near the virtual objects. Because a conventional touch-panel system detects the user's operation on the display screen but the touching point differs from the actual displaying space, it is important to realize that the user can operate at the same space. A typical method is to use the computer vision. In this paper, the authors propose the interface system using a theremin which is a musical instrument having the unusual aspect of being controlled by the performer's hand motions near the antennas.

  6. [Photosynthetic fluorescence characteristics of floating-leaved and submersed macrophytes commonly found in Taihu Lake].

    PubMed

    Song, Yu-zhi; Cai, Wei; Qin, Bo-qiang

    2009-03-01

    Some aquatic macrophytes commonly found in Taihu Lake, including Trapa bispinosa, Nymphyoides peltatum, Vallisneria natans, and Hydrilla verticillata were collected, and their maximal quantum yield of photosystem II (Fv/Fm) as well as the rapid light curves (RLCs) under conditions of light adaptation and dark adaptation were measured in situ by using a submersible and pulse-amplitude modulated fluorometer (Diving-PAM). The results showed that floating-leaved plants T. bispinosa and N. peltatum had higher potential maximum photosynthetic capacity than submerged macrophytes V. natans and H. verticillata. The measured maximal quantum yield of T. bispinosa, N. peltatum, V. natans, and H. verticillata was 0.837, 0.831, 0.684, and 0.764, respectively. Both the maximal relative electron transport rate and the half saturation point of light intensity of T. bispinosa and N. peltatum were higher than those of V. natans and H. verticillata, especially under the condition of light adaptation. PMID:19637593

  7. Steady solute fields induced by differential rotation in a small floating zone

    NASA Astrophysics Data System (ADS)

    Harriott, George M.; Brown, Robert A.

    1984-11-01

    The relationship between flow structure and solute field during mass transfer of a dilute component is analyzed for the multi-cellular rotating flows in a small-scale floating zone. When the recirculating flows are weak, a closed-form solution clearly shows the link between convection pattern and solute distribution across the surface of the growing solid. In the limit of strong convection, finite-element calculations demonstrate the tendency of the composition to become uniform over the majority of the melt. The radial non-uniformity of solute concentration across the solid surface can be severe, even in the presence of vigorous bulk motion; however, the compositional non-uniformity is greatest when the recirculating motion is comparable to the rate of crystal growth. In this case, segregation of more than 100% the average concentration is predicted and points to the danger in attempting to grow compositionally uniform crystals from a nearly convectionless melt.

  8. Proton production, neutralisation and reduction in a floating water bridge

    NASA Astrophysics Data System (ADS)

    Sammer, Martina; Wexler, Adam D.; Kuntke, Philipp; Wiltsche, Helmar; Stanulewicz, Natalia; Lankmayr, Ernst; Woisetschläger, Jakob; Fuchs, Elmar C.

    2015-10-01

    This work reports on proton production, transport, reduction and neutralization in floating aqueous bridges under the application of a high dc voltage (‘floating water bridge’). Recently possible mechanisms for proton transfer through the bridge were suggested. In this work we visualize and describe the production of protons in the anolyte and their neutralization in the catholyte. Apart from that, protons are reduced to hydrogen due to electrolysis. Microbubbles are detached instantly, due to the electrohydrodynamic flow at the electrode surface. No larger, visible bubbles are formed and the system degasses through the bridge due to its higher local temperature. A detailed analysis of trace elements originating from beaker material, anode or the atmosphere is presented, showing that their influence on the overall conduction compared to the contribution of protons is negligible. Finally, an electrochemical rationale of high voltage electrolysis of low ionic strength solutions is presented.

  9. Floating particle trapping and diffusion in vegetated open channel flow

    NASA Astrophysics Data System (ADS)

    Defina, Andrea; Peruzzo, Paolo

    2010-11-01

    In this paper we present early results of laboratory experiments to investigate the transport and diffusion of floating particles (e.g., buoyant seeds) in open channel flow with emergent vegetation. The experiments are aimed at providing a better understanding of the relevant particle-vegetation interaction mechanisms responsible for the observed diffusion processes. Qualitative observational data are then used to set up a stochastic model for floating particle transport and diffusion. Quantitative observations, such as the distribution of distances travelled by a particle before it is permanently captured by a plant and the arrival-time distributions at prescribed cross sections along the vegetated test section, are instead used to calibrate and validate the model. The comparison between theoretical predictions and experimental results is quite satisfactory and suggests that the observed relevant aspects of the particle-vegetation interaction processes are properly described in the model.

  10. The paradox of the floating candle that continues to burn

    NASA Astrophysics Data System (ADS)

    Theodorakis, Stavros; Aristidou, Charalambos

    2012-08-01

    What happens after lighting a paraffin candle that is barely floating in water and kept upright with the aid of an appropriately weighted nail attached to its bottom? Presumably, it should sink because the buoyant force will decrease more than the weight. Surprisingly, the candle will continue to burn, rising slowly above the surface of the water. The reason for this is that the flame forms a well around the wick filled with molten paraffin, while the water keeps the outer walls of the candle cool and unscathed. Thus, the buoyancy hardly changes while the weight is reduced through burning, resulting in a floating candle that will rise above water. We present a quantitative model that describes the formation of the well and verify it experimentally, examining first the case of a candle in the air and then the case of a candle immersed in water.

  11. Using K2 To Find Free-floating Planets

    NASA Astrophysics Data System (ADS)

    Henderson, Calen

    2015-12-01

    K2's Campaign 9 (K2C9) will conduct a several square-degree microlensing survey toward the Galactic bulge to detect exoplanets simultaneously from the ground and from space. The ˜0.5 AU baseline between K2 and the Earth during C9 will facilitate satellite parallax measurements for hundreds of microlensing events, some with planetary signatures, allowing for the determination of the mass of and distance to the lens systems. For short timescale events, with durations of ˜1 day, a determination of the parallax will identify that the cause is in fact a very low-mass object, i.e., a free-floating planet. Subsquent high-resolution NIR photometric follow-up can then distinguish between a planet that is widely separated from but gravitationally bound to a host star and one that is truly free-floating.

  12. Solution processed molecular floating gate for flexible flash memories.

    PubMed

    Zhou, Ye; Han, Su-Ting; Yan, Yan; Huang, Long-Biao; Zhou, Li; Huang, Jing; Roy, V A L

    2013-01-01

    Solution processed fullerene (C60) molecular floating gate layer has been employed in low voltage nonvolatile memory device on flexible substrates. We systematically studied the charge trapping mechanism of the fullerene floating gate for both p-type pentacene and n-type copper hexadecafluorophthalocyanine (F16CuPc) semiconductor in a transistor based flash memory architecture. The devices based on pentacene as semiconductor exhibited both hole and electron trapping ability, whereas devices with F16CuPc trapped electrons alone due to abundant electron density. All the devices exhibited large memory window, long charge retention time, good endurance property and excellent flexibility. The obtained results have great potential for application in large area flexible electronic devices. PMID:24172758

  13. Solution processed molecular floating gate for flexible flash memories

    PubMed Central

    Zhou, Ye; Han, Su-Ting; Yan, Yan; Huang, Long-Biao; Zhou, Li; Huang, Jing; Roy, V. A. L.

    2013-01-01

    Solution processed fullerene (C60) molecular floating gate layer has been employed in low voltage nonvolatile memory device on flexible substrates. We systematically studied the charge trapping mechanism of the fullerene floating gate for both p-type pentacene and n-type copper hexadecafluorophthalocyanine (F16CuPc) semiconductor in a transistor based flash memory architecture. The devices based on pentacene as semiconductor exhibited both hole and electron trapping ability, whereas devices with F16CuPc trapped electrons alone due to abundant electron density. All the devices exhibited large memory window, long charge retention time, good endurance property and excellent flexibility. The obtained results have great potential for application in large area flexible electronic devices. PMID:24172758

  14. Topsides equipment, operating flexibility key floating LNG design

    SciTech Connect

    Yost, K.; Lopez, R.; Mok, J.

    1998-03-09

    Use of a large-scale floating liquefied natural gas (LNG) plant is an economical alternative to an onshore plant for producing from an offshore field. Mobil Technology Co., Dallas, has advanced a design for such a plant that is technically feasible, economical, safe, and reliable. Presented were descriptions of the general design basis, hull modeling and testing, topsides and storage layouts, and LNG offloading. But such a design also presents challenges for designing topsides equipment in an offshore environment and for including flexibility and safety. These are covered in this second article. Mobil`s floating LNG plant design calls for a square concrete barge with a moon-pool in the center. It is designed to produce 6 million tons/year of LNG with up to 55,000 b/d of condensate from 1 bcfd of raw feed gas.

  15. A floating water bridge produces water with excess charge

    NASA Astrophysics Data System (ADS)

    Fuchs, Elmar C.; Sammer, Martina; Wexler, Adam D.; Kuntke, Philipp; Woisetschläger, Jakob

    2016-03-01

    Excess positive and negative Bjerrum-defect like charge (protonic and ‘aterprotonic’, from ancient Greek ἄ'τɛρ, ‘without’) in anolyte and catholyte of high voltage electrolysis of highly pure water was found during the so-called ‘floating water bridge’ experiment. The floating water bridge is a special case of an electrohydrodynamic liquid bridge and constitutes an intriguing phenomenon that occurs when a high potential difference (~kV cm-1) is applied between two beakers of water. To obtain such results impedance spectroscopy was used. This measurement technique allows the depiction and simulation of complex aqueous systems as simple electric circuits. In the present work we show that there is an additional small contribution from the difference in conductivity between anolyte and catholyte which cannot be measured with a conductivity meter, but is clearly visible in an impedance spectrum.

  16. Contactless heater floating zone refining and crystal growth

    NASA Technical Reports Server (NTRS)

    Kou, Sindo (Inventor); Lan, Chung-Wen (Inventor)

    1993-01-01

    Floating zone refining or crystal growth is carried out by providing rapid relative rotation of a feed rod and finish rod while providing heat to the junction between the two rods so that significant forced convection occurs in the melt zone between the two rods. The forced convection distributes heat in the melt zone to allow the rods to be melted through with a much shorter melt zone length than possible utilizing conventional floating zone processes. One of the rods can be rotated with respect to the other, or both rods can be counter-rotated, with typical relative rotational speeds of the rods ranging from 200 revolutions per minute (RPM) to 400 RPM or greater. Zone refining or crystal growth is carried out by traversing the melt zone through the feed rod.

  17. Shell chooses floating units for central N. Sea projects

    SciTech Connect

    Weener, R.

    1996-08-19

    As new fields awaiting development tend to become smaller, as oil prices remain flat, and as reserves are exploited in ever more-remote and deep waters, so interest in floating production systems is growing. The Shell Group has long experience of floating production, storage, and offtake (FPSO) facilities, subsea development equipment, and other related technologies such as flexible risers. The first Shell FPSO was installed in Castellon field in the Mediterranean Sea in 1977. Since then FPSO systems have been installed in many areas of the world and have evolved as safe and environmentally sound installations which can confidently be employed in ever more-demanding areas. The paper describes FPSO evaluation, North Sea status, FPSOs in Shell Exploration and Production, Curlew field plans, further developments, FPSO market, and future trends.

  18. Preparation and evaluation of floating tablets of pregabalin.

    PubMed

    Kanwar, Navjot; Kumar, Rakesh; Sarwal, Amita; Sinha, V R

    2016-01-01

    Floating tablets of pregabalin were prepared using different concentrations of the gums (xanthan gum and guar gum), Carbopol 974P NF and HPMC K100. Optimized formulations were studied for physical tests, floating time, swelling behavior, in vitro release studies and stability studies. In vitro drug release was higher for tablet batches containing guar and xanthan gum as compared to the batches containing Carbopol 974P NF. Tablet batches were subjected to stability studies and evaluated by different parameters (drug release, drug content, FTIR and DSC studies). The optimized tablet batch was selected for in vivo pharmacodynamic studies (PTZ induced seizures). The results obtained showed that the onset of jerks and clonus were delayed and extensor phase was abolished with time in treated groups. A significant difference (p > 0.05) was observed in control and treated group behavior indicating an excellent activity of the formulation for a longer period (>12 h). PMID:26146770

  19. Floating and flying ferrofluid bridges induced by external magnetic fields

    NASA Astrophysics Data System (ADS)

    Ma, Rongchao; Zhou, Yixin; Liu, Jing

    2015-04-01

    A ferrofluid is a mixture that exhibits both magnetism and fluidity. This merit enables the ferrofluid to be used in a wide variety of areas. Here we show that a floating ferrofluid bridge can be induced between two separated boards under a balanced external magnetic field generated by two magnets, while a flying ferrofluid bridge can be induced under an unbalanced external magnetic field generated by only one magnet. The mechanisms of the ferrofluid bridges were discussed and the corresponding mathematical equations were also established to describe the interacting magnetic force between the ferro particles inside the ferrofluid. This work answered a basic question that, except for the well-known floating water bridges that are related to electricity, one can also build up a liquid bridge that is related to magnetism.

  20. Quantitative Comparison of the Responses of Three Floating Platforms

    SciTech Connect

    Jonkman, J.; Matha, D.

    2010-03-01

    This report presents a comprehensive dynamic-response analysis of three offshore floating wind turbine concepts. Models were composed of one 5-MW turbine supported on land and three 5-MW turbines located offshore on a tension leg platform, a spar buoy, and a barge. A loads and stability analysis adhering to the procedures of international design standards was performed for each model using the fully coupled time-domain aero-hydro-servo-elastic design code FAST with AeroDyn and HydroDyn. The concepts are compared based on the calculated ultimate loads, fatigue loads, and instabilities. The results of this analysis will help resolve the fundamental design trade-offs between the floating-system concepts.

  1. SEMICONDUCTOR DEVICES: Trench gate IGBT structure with floating P region

    NASA Astrophysics Data System (ADS)

    Mengliang, Qian; Zehong, Li; Bo, Zhang; Zhaoji, Li

    2010-02-01

    A new trench gate IGBT structure with a floating P region is proposed, which introduces a floating P region into the trench accumulation layer controlled IGBT (TAC-IGBT). The new structure maintains a low on-state voltage drop and large forward biased safe operating area (FBSOA) of the TAC-IGBT structure while reduces the leakage current and improves the breakdown voltage. In addition, it enlarges the short circuit safe operating area (SCSOA) of the TAC-IGBT, and is simple in fabrication and design. Simulation results indicate that, for IGBT structures with a breakdown voltage of 1200 V, the leakage current of the new trench gate IGBT structure is one order of magnitude lower than the TAC-IGBT structure and the breakdown voltage is 150 V higher than the TAC-IGBT.

  2. Control of the floating potential using dual-frequency

    NASA Astrophysics Data System (ADS)

    Park, Il-Seo; Kim, Dong-Hwan; Chung, Chin-Wook

    2016-06-01

    Variation of the floating potential in a Langmuir probe was investigated. When the dual frequencies ( ω1, ω2 ) were applied to the probe, the intermodulation frequencies, which are the linear combinations of two frequencies ( a ω1±b ω2 ), as well as the harmonic frequencies ( a ω1,b ω2 ), were induced by sheath nonlinearity. However, when two frequencies had a consecutive relationship ( ω2=2 ω1 ), the DC components of the intermodulation frequencies ( a ω1±b ω2=0 ) were generated. This is known as the sheath rectification effect, which causes additional voltage to the floating potential at the probe. In our work, the induced voltage can be controlled by the phase difference between the two consecutive frequencies, and it was found to be in good agreement with the theoretical result, which is governed by the temperature of the high energy electrons.

  3. Classifying Floating Potential Measurement Unit Data Products as Science Data

    NASA Technical Reports Server (NTRS)

    Coffey, Victoria; Minow, Joseph

    2015-01-01

    We are Co-Investigators for the Floating Potential Measurement Unit (FPMU) on the International Space Station (ISS) and members of the FPMU operations and data analysis team. We are providing this memo for the purpose of classifying raw and processed FPMU data products and ancillary data as NASA science data with unrestricted, public availability in order to best support science uses of the data.

  4. Matched filter based detection of floating mines in IR spacetime

    NASA Astrophysics Data System (ADS)

    Borghgraef, Alexander; Lapierre, Fabian; Philips, Wilfried; Acheroy, Marc

    2009-09-01

    Ship-based automatic detection of small floating objects on an agitated sea surface remains a hard problem. Our main concern is the detection of floating mines, which proved a real threat to shipping in confined waterways during the first Gulf War, but applications include salvaging,search-and-rescue and perimeter or harbour defense. IR video was chosen for its day-and-night imaging capability, and its availability on military vessels. Detection is difficult because a rough sea is seen as a dynamic background of moving objects with size order, shape and temperature similar to those of the floating mine. We do find a determinant characteristic in the target's periodic motion, which differs from that of the propagating surface waves composing the background. The classical detection and tracking approaches give bad results when applied to this problem. While background detection algorithms assume a quasi-static background, the sea surface is actually very dynamic, causing this category of algorithms to fail. Kalman or particle filter algorithms on the other hand, which stress temporal coherence, suffer from tracking loss due to occlusions and the great noise level of the image. We propose an innovative approach. This approach uses the periodicity of the objects movement and thus its temporal coherence. The principle is to consider the video data as a spacetime volume similar to a hyperspectral data cube by replacing the spectral axis with a temporal axis. We can then apply algorithms developed for hyperspectral detection problems to the detection of small floating objects. We treat the detection problem using multilinear algebra, designing a number of finite impulse response filters (FIR) maximizing the target response. The algorithm was applied to test footage of practice mines in the infrared.

  5. Study the Effect of Urban Ecosystem to Floating Population

    NASA Astrophysics Data System (ADS)

    Tu, Wubin; Zhang, Lingxian; Zhang, Xiaoshuan; Fu, Zetian

    The urban ecosystem is a complex system hat are compounded of environment -economic-social ,the factors of urban ecosystem affect the decision of the floating population to chose city .In this paper ,we according to the urban ecosystem to design the questionnaire ,and study the weights of the factors that influence the decision by AHP ,and find that economy is most important which is 0.6806, the society and ecological environment are 0.2014and0.1180.

  6. Floated pallet definition study. Volume 4: Summary volume

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The conceptual design of a suspension system for the Floated Pallet and a retention system to support the pallet during launch, maneuvering and descent are described. In addition, a control moment gyroscope support equipment configuration study including installation and an experiment mount and erection study was performed. The impact of these separate hardware studies on the existing pallet configuration was assessed and a modified pallet common module defined.

  7. Cascade Analysis of a Floating Wind Turbine Rotor

    NASA Astrophysics Data System (ADS)

    Eliassen, Lene; Jakobsen, Jasna B.; Knauer, Andreas; Nielsen, Finn Gunnar

    2014-12-01

    Mounting a wind turbine on a floating foundation introduces more complexity to the aerodynamic loading. The floater motion contains a wide range of frequencies. To study some of the basic dynamic load effect on the blades due to these motions, a two-dimensional cascade approach, combined with a potential vortex method, is used. This is an alternative method to study the aeroelastic behavior of wind turbines that is different from the traditional blade element momentum method. The analysis tool demands little computational power relative to a full three dimensional vortex method, and can handle unsteady flows. When using the cascade plane, a "cut" is made at a section of the wind turbine blade. The flow is viewed parallel to the blade axis at this cut. The cascade model is commonly used for analysis of turbo machineries. Due to the simplicity of the code it requires little computational resources, however it has limitations in its validity. It can only handle two-dimensional potential flow, i.e. including neither three-dimensional effects, such as the tip loss effect, nor boundary layers and stall effects are modeled. The computational tool can however be valuable in the overall analysis of floating wind turbines, and evaluation of the rotor control system. A check of the validity of the vortex panel code using an airfoil profile is performed, comparing the variation of the lift force, to the theoretically derived Wagner function. To analyse the floating wind turbine, a floating structure with hub height 90 m is chosen. An axial motion of the rotor is considered.

  8. Floating Potential Probe Langmuir Probe Data Reduction Results

    NASA Technical Reports Server (NTRS)

    Morton, Thomas L.; Minow, Joseph I.

    2002-01-01

    During its first five months of operations, the Langmuir Probe on the Floating Potential Probe (FPP) obtained data on ionospheric electron densities and temperatures in the ISS orbit. In this paper, the algorithms for data reduction are presented, and comparisons are made of FPP data with ground-based ionosonde and Incoherent Scattering Radar (ISR) results. Implications for ISS operations are detailed, and the need for a permanent FPP on ISS is examined.

  9. Classification and certification requirements for floating production systems

    SciTech Connect

    Bowie, R.D.; Richardson, K.L.

    1995-12-31

    Floating Production Systems (FPSs) can be either, custom built or a converted semi-submersible, tanker or barge. The paper describes the necessary steps to be taken for the Classification and Certification of FPSs and FPSOS. The paper outlines the latest Classification and certification requirements for both semi-submersible and ship type FPSS. Classification and regulatory requirements for the Hull Structure, Stability, Station Keeping, Shipboard and Production Systems are discussed.

  10. Promoting microstructural uniformity during floating-zone crystal growth

    NASA Astrophysics Data System (ADS)

    Grugel, R. N.; Lee, C. P.; Anilkumar, A. V.; Wang, T. G.; Shen, X. F.; Cröll, A.; Bune, A.

    1999-01-01

    It is demonstrated in floating-zone configurations utilizing silicone oil and nitrate salts that mechanically induced vibration effectively minimizes detrimental, gravity independent, thermocapillary flow. The processing parameters leading to crystal improvement and aspects of the on-going modeling effort are discussed. Plans for applying the crystal growth technique to commercially relevant materials, e.g., silicon, as well as the value of processing in a microgravity environment are presented.

  11. Various options for electronic rebalancing loops of strapdown floated gyroscopes

    NASA Astrophysics Data System (ADS)

    Ribeiro, Jose Francisco

    1991-07-01

    A general view is presented of the different concepts for the problem of electronic rebalancing loops of strapdown floated gyroscopes. The loops of rebalancing analyzed are analogue, binary, ternary, and time modulated types. In particular, the errors are discussed along with the interfaces and the electronic implementation of each one of the loops. The rebalancing control loops are compared and one of them is selected for future analysis and simulation.

  12. Performance of floating oil booms in unsheltered waters

    NASA Astrophysics Data System (ADS)

    Iglesias, Gregorio; Castro, Alberte

    2013-04-01

    Oil booms are a fundamental tool to diminish the impact of an oil spill. They tend to perform reasonably well in sheltered waters, e.g. within a harbour. However, their performance is often inadequate in open water conditions, under waves, winds and currents. And it is precisely in those conditions that they are needed if oil slicks are to be prevented from reaching certain particularly sensitive areas, such as estuaries, rias, etc. (Castro et al., 2010; Iglesias et al., 2010). In this work the performance of floating oil booms under waves and currents is assessed on the basis of laboratory experiments carried out in a state-of-the-art wave-current flume. Different oil boom models are used, representative of booms with long and short skirts and with different weights. The results show that different booms behave very differently under waves and currents, hence the importance of selecting the boom design that is appropriate for the actual conditions under which it will have to contain the oil slick. Thus, different oil booms should be used for different areas. References A. Castro, G. Iglesias, R. Carballo, J.A. Fraguela, 2010. Floating boom performance under waves and currents, Journal of Hazardous Materials 174, 226-235 G. Iglesias, A.Castro, J.A.Fraguela, 2010. Artificial intelligence applied to floating boom behavior under waves and currents, Ocean Engineering 37, 1513-1521.

  13. Using K2 to Find Free-floating Planets

    NASA Astrophysics Data System (ADS)

    Henderson, Calen B.

    2016-01-01

    In 2011, Sumi et al. announced the discovery of an excess of short-timescale microlensing events, which they inferred to be caused by a population of unbound planetary-mass objects. Their result implies that these free-floating planet candidates may constitute an overwhelming fraction of the mass budget for planet formation. K2's Campaign 9 (K2C9) will conduct a ~4 square-degree microlensing survey toward the Galactic bulge and is our first and potentially only opportunity to perform a synoptic survey to measure the masses of a substantial number of short-timescale events. The ˜0.5 AU baseline between K2 and the Earth during C9 will facilitate satellite parallax measurements for short-timescale events, with durations of ˜1 day, which will identify that the cause of the event is in fact a very low-mass object, i.e., a free-floating planet candidate. By taking near-infrared (NIR) photometry during the event and comparing to high-resolution NIR photometry after the event is over, we can then distinguish between a planet that is widely separated from but gravitationally bound to a host star and one that is truly free-floating. Here we overview this procedure, describe the resources available to accomplish it, and detail the expected yields.

  14. Modelling hydrological management for the restoration of acidified floating fens

    NASA Astrophysics Data System (ADS)

    Dekker, Stefan C.; Barendregt, Aat; Bootsma, Margien C.; Schot, Paul P.

    2005-12-01

    Wetlands show a large decline in biodiversity. To protect and restore this biodiversity, many restoration projects are carried out. Hydrology in wetlands controls the chemical and biological processes and may be the most important factor regulating wetland function and development. Hydrological models may be used to simulate these processes and to evaluate management scenarios for restoration. HYDRUS2D, a combined saturated-unsaturated groundwater flow and transport model, is presented. This simulates near-surface hydrological processes in an acidified floating fen, with the aim to evaluate the effect of hydrological restoration in terms of conditions for biodiversity. In the acidified floating fen in the nature reserve Ilperveld (The Netherlands), a trench system was dug for the purpose of creating a runoff channel for acid rainwater in wet periods and to enable circum-neutral surface water to enter the fen in dry periods. The model is calibrated against measured conductivity values for a 5 year period. From the model simulations, it was found that lateral flow in the floating raft is limited. Furthermore, the model shows that the best management option is a combination of trenches and inundation, which gave the best soil water quality in the root zone. It is concluded that hydrological models can be used for the calculation of management scenarios in restoration projects. The combined saturated-unsaturated model concept used in this paper is able to incorporate the governing hydrological processes in the wetland root zones. Copyright

  15. Characterization of floating element balance for field panel testing

    NASA Astrophysics Data System (ADS)

    Hunsucker, J. Travis; Gardner, Harrison; Swain, Geoffrey

    2015-11-01

    Multiple experiments were performed to investigate and characterize the uncertainty and bias of a through-hull flush mounted floating element balance designed to measure the hydrodynamic drag forces of biofouling and marine coatings on 25 x 30 cm test panels. The instrument is located in a wet well on the aft portion of a 27' Chris Craft Commander. Testing occurs over a series of speeds ranging from a Froude number of 0.50-2.20 on calm days (force 3 or less) in waters along the central east coast of Florida. Recent modifications have been made to the instrumentation in an effort to improve the overall accuracy of the system. This study compares frictional drag measurements of the floating element balance to those obtained using the Clauser chart and Preston tube methods for a smooth surface. Boundary layer velocity profiles are examined to understand the nature of the flow over the testing section. Roughness function values for 60 and 220 grit sandpaper were calculated from data obtained using the floating element balance. These values were compared with previous work to examine the overall bias of the methodology. Repeat measurements for a smooth panel were analyzed to characterize the overall uncertainty in the system. This research was supported by the Office of Naval Research under grants N00014-10-1-0919 and N00014-11-1-0915.

  16. Floating ice-algal aggregates below melting arctic sea ice.

    PubMed

    Assmy, Philipp; Ehn, Jens K; Fernández-Méndez, Mar; Hop, Haakon; Katlein, Christian; Sundfjord, Arild; Bluhm, Katrin; Daase, Malin; Engel, Anja; Fransson, Agneta; Granskog, Mats A; Hudson, Stephen R; Kristiansen, Svein; Nicolaus, Marcel; Peeken, Ilka; Renner, Angelika H H; Spreen, Gunnar; Tatarek, Agnieszka; Wiktor, Jozef

    2013-01-01

    During two consecutive cruises to the Eastern Central Arctic in late summer 2012, we observed floating algal aggregates in the melt-water layer below and between melting ice floes of first-year pack ice. The macroscopic (1-15 cm in diameter) aggregates had a mucous consistency and were dominated by typical ice-associated pennate diatoms embedded within the mucous matrix. Aggregates maintained buoyancy and accumulated just above a strong pycnocline that separated meltwater and seawater layers. We were able, for the first time, to obtain quantitative abundance and biomass estimates of these aggregates. Although their biomass and production on a square metre basis was small compared to ice-algal blooms, the floating ice-algal aggregates supported high levels of biological activity on the scale of the individual aggregate. In addition they constituted a food source for the ice-associated fauna as revealed by pigments indicative of zooplankton grazing, high abundance of naked ciliates, and ice amphipods associated with them. During the Arctic melt season, these floating aggregates likely play an important ecological role in an otherwise impoverished near-surface sea ice environment. Our findings provide important observations and measurements of a unique aggregate-based habitat during the 2012 record sea ice minimum year. PMID:24204642

  17. Formulation and Evaluation of Controlled Release Floating Microballoons of Stavudine

    PubMed Central

    Vidyadhara, Suryadevara; Sasidhar, Reddyvalam Lankapalli; Balakrishna, Talamanchi; Balaji, Boyapati; Amrutha, Ravi

    2015-01-01

    The aim of this study was to formulate and evaluate stavudine floating microballoons for controlled drug release. Initially, the drug-loaded low-density granular pellets were prepared with hydroxypropyl methylcellulose E5 grade and by using isopropyl alcohol as a granulating fluid. Further, the low-density granular pellets were subjected to microencapsulation by an emulsion evaporation technique using ethyl cellulose 7 cps and Eudragit S 100 as coating polymers and 1% w/v polyethylene glycol 400 as aqueous phase. The prepared microballoons were characterized for their particle size analysis, angle of repose, and compressibility index. The in vitro release studies were performed in 0.1 N HCl as medium. The prepared microballoons were free-flowing and spherical in shape. From all the formulations, F5E and F5F can be considered as promising controlled release floating microballoons of stavudine providing first-order release over a period of 12 hours, with a minimum floating lag time of 1 minute. It was found that the ratio of the drug & polymer, stirring speed, and concentration of surfactant were the most significant variables which influenced the size of the stavudine microballoons under the applied experimental conditions. PMID:26839847

  18. Floating Ice-Algal Aggregates below Melting Arctic Sea Ice

    PubMed Central

    Assmy, Philipp; Ehn, Jens K.; Fernández-Méndez, Mar; Hop, Haakon; Katlein, Christian; Sundfjord, Arild; Bluhm, Katrin; Daase, Malin; Engel, Anja; Fransson, Agneta; Granskog, Mats A.; Hudson, Stephen R.; Kristiansen, Svein; Nicolaus, Marcel; Peeken, Ilka; Renner, Angelika H. H.; Spreen, Gunnar; Tatarek, Agnieszka; Wiktor, Jozef

    2013-01-01

    During two consecutive cruises to the Eastern Central Arctic in late summer 2012, we observed floating algal aggregates in the melt-water layer below and between melting ice floes of first-year pack ice. The macroscopic (1-15 cm in diameter) aggregates had a mucous consistency and were dominated by typical ice-associated pennate diatoms embedded within the mucous matrix. Aggregates maintained buoyancy and accumulated just above a strong pycnocline that separated meltwater and seawater layers. We were able, for the first time, to obtain quantitative abundance and biomass estimates of these aggregates. Although their biomass and production on a square metre basis was small compared to ice-algal blooms, the floating ice-algal aggregates supported high levels of biological activity on the scale of the individual aggregate. In addition they constituted a food source for the ice-associated fauna as revealed by pigments indicative of zooplankton grazing, high abundance of naked ciliates, and ice amphipods associated with them. During the Arctic melt season, these floating aggregates likely play an important ecological role in an otherwise impoverished near-surface sea ice environment. Our findings provide important observations and measurements of a unique aggregate-based habitat during the 2012 record sea ice minimum year. PMID:24204642

  19. Exponential flux-controlled memristor model and its floating emulator

    NASA Astrophysics Data System (ADS)

    Liu, Wei; Wang, Fa-Qiang; Ma, Xi-Kui

    2015-11-01

    As commercial memristors are still unavailable in the market, mathematic models and emulators which can imitate the features of the memristor are meaningful for further research. In this paper, based on the analyses of characteristics of the q-φ curve, an exponential flux-controlled model, which has the quality that its memductance (memristance) will keep monotonically increasing or decreasing unless the voltage’s polarity reverses (if not approach the boundaries), is constructed. A new approach to designing the floating emulator of the memristor is also proposed. This floating structure can flexibly meet various demands for the current through the memristor (especially the demand for a larger current). The simulations and experiments are presented to confirm the effectiveness of this model and its floating emulator. Project supported by the National Natural Science Foundation of China (Grant Nos. 51377124 and 51221005), the Foundation for the Author of National Excellent Doctoral Dissertation of China (Grant No. 201337), the Program for New Century Excellent Talents in University of China (Grant No. NCET-13-0457), and the Natural Science Basic Research Plan in Shaanxi Province of China (Grant No. 2012JQ7026).

  20. Deterministic sequential isolation of floating cancer cells under continuous flow.

    PubMed

    Tran, Quang D; Kong, Tian Fook; Hu, Dinglong; Marcos; Lam, Raymond H W

    2016-08-01

    Isolation of rare cells, such as circulating tumor cells, has been challenging because of their low abundance and limited timeframes of expressions of relevant cell characteristics. In this work, we devise a novel hydrodynamic mechanism to sequentially trap and isolate floating cells in biosamples. We develop a microfluidic device for the sequential isolation of floating cancer cells through a series of microsieves to obtain up to 100% trapping yield and >95% sequential isolation efficiency. We optimize the trappers' dimensions and locations through both computational and experimental analyses using microbeads and cells. Furthermore, we investigated the functional range of flow rates for effective sequential cell isolation by taking the cell deformability into account. We verify the cell isolation ability using the human breast cancer cell line MDA-MB-231 with perfect agreement with the microbead results. The viability of the isolated cells can be maintained for direct identification of any cell characteristics within the device. We further demonstrate that this device can be applied to isolate the largest particles from a sample containing multiple sizes of particles, revealing its possible applicability in isolation of circulating tumor cells in cancer patients' blood. Our study provides a promising sequential cell isolation strategy with high potential for rapid detection and analysis of general floating cells, including circulating tumor cells and other rare cell types. PMID:27387093

  1. Formulation and Evaluation of Controlled Release Floating Microballoons of Stavudine.

    PubMed

    Vidyadhara, Suryadevara; Sasidhar, Reddyvalam Lankapalli; Balakrishna, Talamanchi; Balaji, Boyapati; Amrutha, Ravi

    2015-01-01

    The aim of this study was to formulate and evaluate stavudine floating microballoons for controlled drug release. Initially, the drug-loaded low-density granular pellets were prepared with hydroxypropyl methylcellulose E5 grade and by using isopropyl alcohol as a granulating fluid. Further, the low-density granular pellets were subjected to microencapsulation by an emulsion evaporation technique using ethyl cellulose 7 cps and Eudragit S 100 as coating polymers and 1% w/v polyethylene glycol 400 as aqueous phase. The prepared microballoons were characterized for their particle size analysis, angle of repose, and compressibility index. The in vitro release studies were performed in 0.1 N HCl as medium. The prepared microballoons were free-flowing and spherical in shape. From all the formulations, F5E and F5F can be considered as promising controlled release floating microballoons of stavudine providing first-order release over a period of 12 hours, with a minimum floating lag time of 1 minute. It was found that the ratio of the drug & polymer, stirring speed, and concentration of surfactant were the most significant variables which influenced the size of the stavudine microballoons under the applied experimental conditions. PMID:26839847

  2. Floating Probe Assembly for Measuring Temperature of Water

    NASA Technical Reports Server (NTRS)

    Selinsky, T.; Stewart, Randy; Ruffin, Clyde

    2002-01-01

    A floating apparatus denoted a temperature probe aquatic suspension system (TPASS) has been developed for measuring the temperature of an ocean, lake, or other natural body of water at predetermined depths. Prior instruments built for the same purpose were found to give inaccurate readings because the apparatuses themselves significantly affected the temperatures of the water in their vicinities. The design of the TPASS is intended to satisfy a requirement to minimize the perturbation of the temperatures to be measured. The TPASS includes a square-cross-section aluminum rod 28 in. (approx. = 71 cm) long with floats attached at both ends. Each float includes five polystyrene foam disks about 3/4 in. (approx. = 1.9 cm) thick and 2.5 in. (approx. = 6.4 cm) in diameter. The disks are stacked to form cylinders, bolted to the rod, and covered with hollow plastic sleeves. A metal sleeve is clamped to the middle of the aluminum rod, from whence it hangs down into the water. Temperature probes (which can be thermocouples, thermistors, or resistance temperature devices) are placed within the sleeve at the desired measurement depths. Wires from the temperature probes are routed to the input terminals of a data logger. This work was done by Randy

  3. Floating Probe Assembly for Measuring Temperature of Water

    NASA Technical Reports Server (NTRS)

    Stewart, Randy; Ruffin, Clyde

    2002-01-01

    A floating apparatus denoted a temperature probe aquatic suspension system (TPASS) has been developed for measuring the temperature of an ocean, lake, or other natural body of water at predetermined depths. Prior instruments built for the same purpose were found to give inaccurate readings because the apparatuses themselves significantly affected the temperatures of the water in their vicinities. The design of the TPASS is intended to satisfy a requirement to minimize the perturbation of the temperatures to be measured. The TPASS includes a square-cross-section aluminum rod 28 in. (=71 cm) long with floats attached at both ends. Each float includes five polystyrene foam disks about 3/4 in.(=1.9 cm) thick and 2.5 in. (=6.4 cm) in diameter. The disks are stacked to form cylinders, bolted to the rod, and covered with hollow plastic sleeves. A metal sleeve is clamped to the middle of the aluminum rod, from whence it hangs down into the water. Temperature probes (which can be thermocouples, thermistors, or resistance temperature devices) are placed within the sleeve at the desired measurement depths. Wires from the temperature probes are routed to the input terminals of a data logger.

  4. Pipe-type cable floated into place across river

    SciTech Connect

    Not Available

    1994-07-01

    In 1992, the 60-yr-old Portland Bridge across the Fore River in Maine had to be replaced with a completely new structure. Unfortunately for Central Maine Power Co, three 34.5-kV submarine cables and a 115-kV pipe-type cable (plus spare pipe), which paralleled the old structure, were directly in the path planned for the footing of the new bridge. Before construction could begin, these had to be relocated to the other side of the old bridge. Because of space limitations in the crossing area, the two 1200-ft replacement pipes were assembled one mile upstream and floated down to the bridge using specially made polystyrene floats. The trench, measuring 20 ft wide and 20 ft deep, was dredged across the river bottom and designed to accommodate both the submarine and pipe-type cables with adequate spacing. First, the two pipes were floated into position and sunk into the trench. Then the three submarine cables were laid simultaneously from a cable barge. Divers ensured that there was adequate spacing between the medium- and high-voltage cables. 10 figs.

  5. Floating junk bonnet protects liner top from debris

    SciTech Connect

    Telfer, G. ); Sweeney, D. )

    1994-09-12

    A new design of debris protection system, the floating junk bonnet, for liner tops prevents well debris from entering the liner top polished bore receptacle (PBR) and sticking the setting tools. The floating junk bonnet improves the recovery of liner setting tools from the well no matter how severe the debris problem is. Well debris (formation cuttings, fines, mud solids, cement solids, foreign bodies, etc) entering the linear top PBR during cementing operations has been a serious problem for many operators. In some cases, this problem has led to liner hanger setting tools sticking in the liner top PBR. The setting tool could then become cemented in place, resulting in an expensive fishing job or sidetrack. A prototype debris protection system was developed and tested prior to offshore application. The liner protection tool was subsequently successfully used on Nelson project development wells in the U.K. North Sea. The paper discusses debris accumulation, the junket basket, the floating junk bonnet design, test procedures, and field test results.

  6. Tracking beaked whales with a passive acoustic profiler float.

    PubMed

    Matsumoto, Haru; Jones, Christopher; Klinck, Holger; Mellinger, David K; Dziak, Robert P; Meinig, Christian

    2013-02-01

    Acoustic methods are frequently used to monitor endangered marine mammal species. Advantages of acoustic methods over visual ones include the ability to detect submerged animals, to work at night, and to work in any weather conditions. A relatively inexpensive and easy-to-use acoustic float, the QUEphone, was developed by converting a commercially available profiler float to a mobile platform, adding acoustic capability, and installing the ERMA cetacean click detection algorithm of Klinck and Mellinger [(2011). J. Acoust. Soc. Am. 129(4), 1807-1812] running on a high-power DSP. The QUEphone was tested at detecting Blainville's beaked whales at the Atlantic Undersea Test and Evaluation Center (AUTEC), a Navy acoustic test range in the Bahamas, in June 2010. Beaked whale were present at AUTEC, and the performance of the QUEphone was compared with the Navy's Marine Mammal Monitoring on Navy Ranges (M3R) system. The field tests provided data useful to evaluate the QUEphone's operational capability as a tool to detect beaked whales and report their presence in near-real time. The range tests demonstrated that the QUEphone's beaked whale detections were comparable to that of M3R's, and that the float is effective at detecting beaked whales. PMID:23363092

  7. Modelling of the MEA float zone using accelerometer data

    NASA Technical Reports Server (NTRS)

    Alexander, J. Iwan D.

    1993-01-01

    During a floating zone experiment involving the growth of indium on a recent orbiter mission, (STS 32) oscillation of the zone shapes were observed to occur in response to the background acceleration. An understanding of the nature of the response of the zone shape to forced (g-jitter) oscillations and predictions of its impact on future experiments is of great interest not only to the PI's but to other commercial and academic investigators who plan to fly similar experiments in the orbiter and on space station. Motivated by this, a 15 month study was undertaken to analyze the nature of the g-sensitivity of the STS 32 floating zone crystal growth experiment. Numerical models were used to describe the time-dependent free surface motion of the zone as it responds to the spacecraft residual acceleration. Relevant experimental data concerning the acceleration environment was obtained from the Honeywell in Space Accelerometer (HISA) investigators through MSFC's ACAP program and processed and analyzed. For the indium floating zone experiment, a series of calculations were made using time-dependent axial accelerations g(t). The form of g(t) included simple sinusoidal disturbances as well as actual data (subject to appropriate filtering) measured on the STS 32 mission. Focus was on the calculation of the response of the free surface of the zone as well as the internal flows and internal heat transfer. The influence of solidification on the response of the zone shape was also examined but found to be negligible.

  8. Water flow and solute transport in floating fen root mats

    NASA Astrophysics Data System (ADS)

    Stofberg, Sija F.; EATM van der Zee, Sjoerd

    2015-04-01

    Floating fens are valuable wetlands, found in North-Western Europe, that are formed by floating root mats when old turf ponds are colonized by plants. These terrestrialization ecosystems are known for their biodiversity and the presence of rare plant species, and the root mats reveal different vegetation zones at a small scale. The vegetation zones are a result of strong gradients in abiotic conditions, including groundwater dynamics, nutrients and pH. To prevent irreversible drought effects such as land subsidence and mineralization of peat, water management involves import of water from elsewhere to maintain constant surface water levels. Imported water may have elevated levels of salinity during dry summers, and salt exposure may threaten the vegetation. To assess the risk of exposure of the rare plant species to salinity, the hydrology of such root mats must be understood. Physical properties of root mats have scarcely been investigated. We have measured soil characteristics, hydraulic conductivity, vertical root mat movement and groundwater dynamics in a floating root mat in the nature reserve Nieuwkoopse Plassen, in the Netherlands. The root mat mostly consists of roots and organic material, in which the soil has a high saturated water content, and strongly varies in its stage of decomposition. We have found a distinct negative correlation between degree of decomposition and hydraulic conductivity, similar to observations for bogs in the literature. Our results show that the relatively young, thin edge of the root mat that colonizes the surface water has a high hydraulic conductivity and floats in the surface water, resulting in very small groundwater fluctuations within the root mat. The older part of the root mat, that is connected to the deeper peat layers is hydrologically more isolated and the material has a lower conductivity. Here, the groundwater fluctuates strongly with atmospheric forcing. The zones of hydraulic properties and vegetation, appear to

  9. Instantaneous stabilization of floating oils by surface application of natural granular materials (beach sand and limestone).

    PubMed

    Boglaienko, Daria; Tansel, Berrin

    2015-02-15

    When granular materials are applied to hydrophobic liquids floating over another liquid (i.e., water), particles form aggregates which can be separated from the floating phase. This concept can be used for controlling mobility of floating oils, especially after oil spills near coastal areas. The objectives of this research were to characterize oil capture efficiency and determine effectiveness of particles for converting the floating phase to a heavier phase for effective separation. Experiments were conducted with South Louisiana crude oil contaminated salt water, limestone and quartz sand. Although the oil removal efficiency increased with the increasing amount of granular material applied, it did not increase linearly. About 50% of the floating oil was removed by aggregates, regardless of the material used, when granular material to floating oil ratio was about 1 g/g. The aggregates separated had higher amounts of oil content when smaller amounts of granular materials were added. PMID:25555617

  10. Experimental study of nonlinear behaviors of a free-floating body in waves

    NASA Astrophysics Data System (ADS)

    He, Ming; Ren, Bing; Qiu, Da-hong

    2016-04-01

    Nonlinear behaviors of a free-floating body in waves were experimentally investigated in the present study. The experiments were carried out for 6 different wave heights and 6 different wave periods to cover a relatively wide range of wave nonlinearities. A charge-coupled device (CCD) camera was used to capture the real-time motion of the floating body. The measurement data show that the sway, heave and roll motions of the floating body are all harmonic oscillations while the equilibrium position of the sway motion drifts in the wave direction. The drift speed is proportional to wave steepness when the size of the floating body is comparable to the wavelength, while it is proportional to the square of wave steepness when the floating body is relatively small. In addition, the drift motion leads to a slightly longer oscillation period of the floating body than the wave period of nonlinear wave and the discrepancy increases with the increment of wave steepness.

  11. Software For Tie-Point Registration Of SAR Data

    NASA Technical Reports Server (NTRS)

    Rignot, Eric; Dubois, Pascale; Okonek, Sharon; Van Zyl, Jacob; Burnette, Fred; Borgeaud, Maurice

    1995-01-01

    SAR-REG software package registers synthetic-aperture-radar (SAR) image data to common reference frame based on manual tie-pointing. Image data can be in binary, integer, floating-point, or AIRSAR compressed format. For example, with map of soil characteristics, vegetation map, digital elevation map, or SPOT multispectral image, as long as user can generate binary image to be used by tie-pointing routine and data are available in one of the previously mentioned formats. Written in FORTRAN 77.

  12. Experimental and numerical investigation of the roll motion behavior of a floating liquefied natural gas system

    NASA Astrophysics Data System (ADS)

    Zhao, WenHua; Yang, JianMin; Hu, ZhiQiang; Xiao, LongFei; Peng, Tao

    2013-03-01

    The present paper does an experimental and numerical investigation of the hydrodynamic interaction and the response of a single point turret-moored Floating Liquefied Natural Gas (FLNG) system, which is a new type of floating LNG (Liquid Natural Gas) platform that consists of a ship-type FPSO hull equipped with LNG storage tanks and liquefaction plants. In particular, this study focuses on the investigation of the roll response of FLNG hull in free-decay motions, white noise waves and also in irregular waves. Model tests of the FLNG system in 60%H filling condition excited by both white noise waves and irregular waves combined with steady wind and current have been carried out. Response Amplitude Operators (RAOs) and time histories of the responses are obtained for sway, roll and yaw motions. Obvious Low Frequency (LF) components of the roll motions are observed, which may be out of expectation. To facilitate the physical understanding of this phenomenon, we filter the roll motions at the period of 30 s into two parts: the Wave Frequency (WF) motions and the Low Frequency (LF) motions respectively. The results indicate that the LF motions are closely related to the sway and yaw motions. Possible reasons for the presence of the LF motions of roll have been discussed in detail, through the comparison with the sway and yaw motions. As for the numerical part, the simulation of the modeled case is conducted with the help of the software SESAM®. A good agreement between experiments and calculations is reported within the scope of trends. However, the numerical simulations should be further improved for the prediction of the FLNG system in the heading sea.

  13. On the design of a prototype model of the floating wave power device ``Mighty Whale``

    SciTech Connect

    Hotta, H.; Washio, Y.; Yokozawa, H.; Pizer, D.J.

    1996-12-31

    The Mighty Whale is a floating wave power device to convert the wave energy to other convenient energy for the conservation of the sea, and to create the calm sea area such as a floating breakwater. JAMSTEC (Japan Marine Science and Technology Center) has been promoting the R and D on this Mighty Whale since 1986. Already, the authors have finished fundamental development by theoretical, numerical and experimental study on the basic Mighty Whale. By 1996, they will finish designing the prototype model of the Mighty Whale, will start to construct it, and will carry out the open sea test between 1998 and 1999 at the coastal sea of Japan. The dimensions of the Mighty Whale are 50m in length, 30m in breadth and it has 3 air chambers, 3 units of the air turbines and generators of 50 kW rated power. It will be moored by mooring chains and anchors at the site of about 35m water depth. The mechanism to absorb the wave energy is of the OWC (Oscillating Water Column) type with the Wells Turbine. Its efficiency to absorb the wave energy is about 40--50% on average in regular waves, and it can make in the lee zone the height of incident waves about one half under 8 sec of the significant wave period. Because of such behavior, and from the view point of sustainable development at the coastal zone, the authors recognize the Mighty Whale can be a convenient and beneficial structure for the coastal development. In this paper, they introduce this design, and discuss the utilization of the Mighty Whale for the coastal development.

  14. Apparatus for removing oil and other floating contaminants from a moving body of water

    DOEpatents

    Strohecker, J.W.

    1973-12-18

    The patent describes a process in which floating contaminants such as oil and solid debris are removed from a moving body of water by employing a skimming system which uses the natural gravitational flow of the water. A boom diagonally positioned across the body of water diverts the floating contaminants over a floating weir and into a retention pond where an underflow weir is used to return contaminant-free water to the moving body of water. The floating weir is ballasted to maintain the contaminant-receiving opening therein slightly below the surface of the water during fluctuations in the water level for skimming the contaminants with minimal water removal.

  15. In vitro and in vivo evaluation of floating riboflavin pellets developed using the melt pelletization process.

    PubMed

    Hamdani, J; Goole, J; Moës, A J; Amighi, K

    2006-10-12

    Floating pellets were prepared using the melt pelletization process in a Mi-Pro high shear mixer (Pro-C-epT, Belgium). Formulations were based on a mixture of Compritol and Precirol as meltable binders and on the use of sodium bicarbonate and tartaric acid as gas-generating agents. Good floating abilities were obtained by using the gas-generating agents in both the inner matrix and the outer coating layer of the pellets. In vitro evaluation of floating capability was performed both by using the resultant weight apparatus and by counting floating pellets at the surface of beakers containing 0.1N HCl solution, in vivo evaluation of floating pellets capabilities was also performed. Riboflavin-containing floating pellets (FRF) were administered orally to nine healthy volunteers versus non-floating pellets (NFRF). Volunteers were divided in two groups, fasted group (n=4) 729 kcal and fed group (n=5) 1634 kcal as the total calorie intake on the testing day. An increase of urinary excretion of riboflavin was observed when the volunteers were dosed with the floating pellets, especially after feeding. As riboflavin has a narrow window of absorption in the upper part of small intestine, this phenomenon could be attributable to the gastric retention of floating pellets. PMID:16815656

  16. The Floating Upper Limb: Multiple Injuries Involving Ipsilateral, Proximal, Humeral, Supracondylar, and Distal Radial Limb.

    PubMed

    Manaan, Qazi; Bashir, Adil; Zahoor, Adnan; Mokhdomi, Taseem A; Danish, Qazi

    2016-09-01

    Floating arm injury represents a common yet complicated injury of the childhood severely associated with limb deformation and even morbidity, if not precisely addressed and credibly operated. Here, we report a rare floating upper limb case of a 9-year-old boy with multiple injuries of ipsilateral proximal humeral, supracondylar and distal radial limb. This is the first report to document such a combined floating elbow and floating arm injury in the same limb. In this report, we discuss the surgical procedures used and recovery of the patient monitored to ascertain the effectiveness of the method in limb reorganisation. PMID:27583121

  17. Formulation and in-vitro evaluation of floating bilayer tablet of lisinopril maleate and metoprolol tartrate.

    PubMed

    Ijaz, Hira; Qureshi, Junaid; Danish, Zeeshan; Zaman, Muhammad; Abdel-Daim, Mohamed; Hanif, Muhammad; Waheed, Imran; Mohammad, Imran Shair

    2015-11-01

    The purpose of this study was to introduce the technology for the development of rate-controlled oral drug delivery system to overcome various physiological problems. Several approaches are being used for the purpose of increasing the gastric retentive time, including floating drug delivery system. Gastric floating lisinopril maleate and metoprolol tartrate bilayer tablets were formulated by direct compression method using the sodium starch glycolate, crosscarmellose sodium for IR layer. Eudragit L100, pectin, acacia as sustained release polymers in different ratios for SR metoprolol tartrate layer and sodium bicarbonate, citric acid as gas generating agents for the floating extended release layer. The floating bilayer tablets of lisinopril maleate and metoprolol tartrate were designed to overcome the various problems associated with conventional oral dosage form. Floating tablets were evaluated for floating lag time, drug contents and in-vitro dissolution profile and different kinetic release models were applied. It was clear that the different ratios of polymers affected the drug release and floating time. L2 and M4 showed good drug release profile and floating behavior. The linear regression and model fitting showed that all formulation followed Higuchi model of drug release model except M4 that followed zero order kinetic. From the study it is evident that a promising controlled release by floating bilyer tablets of lisinopril maleate and metoprolol tartrate can be developed successfully. PMID:26639495

  18. Floating electrode electrowetting on hydrophobic dielectric with an SiO2 layer

    NASA Astrophysics Data System (ADS)

    Khodayari, Mehdi; Hahne, Benjamin; Crane, Nathan B.; Volinsky, Alex A.

    2013-05-01

    Floating electrode electrowetting is caused by dc voltage applied to a liquid droplet on the Cytop surface, without electrical connection to the substrate. The effect is caused by the charge separation in the floating electrode. A highly resistive thermally grown SiO2 layer underneath the Cytop enables the droplet to hold charges without leakage, which is the key contribution. Electrowetting with a SiO2 layer shows a memory effect, where the wetting angle stays the same after the auxiliary electrode is removed from the droplet in both conventional and floating electrode electrowetting. Floating electrode electrowetting provides an alternative configuration for developing advanced electrowetting-based devices.

  19. The Floating Upper Limb: Multiple Injuries Involving Ipsilateral, Proximal, Humeral, Supracondylar, and Distal Radial Limb

    PubMed Central

    Manaan, Qazi; Bashir, Adil; Zahoor, Adnan; Mokhdomi, Taseem A.

    2016-01-01

    Floating arm injury represents a common yet complicated injury of the childhood severely associated with limb deformation and even morbidity, if not precisely addressed and credibly operated. Here, we report a rare floating upper limb case of a 9-year-old boy with multiple injuries of ipsilateral proximal humeral, supracondylar and distal radial limb. This is the first report to document such a combined floating elbow and floating arm injury in the same limb. In this report, we discuss the surgical procedures used and recovery of the patient monitored to ascertain the effectiveness of the method in limb reorganisation. PMID:27583121

  20. Preparation and pharmacokinetics study on gastro-floating sustained-release tablets of troxipide.

    PubMed

    Gao, Yunyun; Gao, Yang; Yin, Fei; Wang, Mi; Wang, Zhenhong; Ye, Tiantian; Yang, Yonggang; Pan, W S; Yang, Xinggang

    2015-01-01

    The purpose of this research aimed at preparing gastro-floating sustained-release tablets of troxipide and a further study on in vitro release and in vivo bioavailability. Under the circumstances of direct powder compression, the floating tablets were successfully prepared with HPMC as main matrix material, Carbopol as assistant matrix material, octadecanol as floating agent and sodium bicarbonate as foaming agent to float by gas-forming. The floating time and accumulative release amount as evaluation indexes were utilized to perform pre-experiment screening and single-factor test, respectively, while central composite design response surface method was applied for formulation optimization, followed by in vivo pharmacokinetic study in beagles after oral administration for floating tablets and commercial tablets used as the control. The results indicated that the floating sustained-release tablets held a better capability for floating and drug release and more satisfactory pharmacokinetic parameters, such as a lower Cmax, a prolonged Tmax, but an equivalent bioavailability calculated by AUC0-24 compared to commercial tablets. So a conclusion was finally drawn that the floating sustained-release tablets possessing a good release property could be suitable for demands of design. PMID:25190152

  1. Verification of New Floating Capabilities in FAST v8: Preprint

    SciTech Connect

    Wendt, F.; Robertson, A.; Jonkman, J.; Hayman, G.

    2015-01-01

    In the latest release of NREL's wind turbine aero-hydro-servo-elastic simulation software, FAST v8, several new capabilities and major changes were introduced. FAST has been significantly altered to improve the simulator's modularity and to include new functionalities in the form of modules in the FAST v8 framework. This paper is focused on the improvements made for the modeling of floating offshore wind systems. The most significant change was to the hydrodynamic load calculation algorithms, which are embedded in the HydroDyn module. HydroDyn is now capable of applying strip-theory (via an extension of Morison's equation) at the member level for user-defined geometries. Users may now use a strip-theory-only approach for applying the hydrodynamic loads, as well as the previous potential-flow (radiation/diffraction) approach and a hybrid combination of both methods (radiation/diffraction and the drag component of Morison's equation). Second-order hydrodynamic implementations in both the wave kinematics used by the strip-theory solution and the wave-excitation loads in the potential-flow solution were also added to HydroDyn. The new floating capabilities were verified through a direct code-to-code comparison. We conducted a series of simulations of the International Energy Agency Wind Task 30 Offshore Code Comparison Collaboration Continuation (OC4) floating semisubmersible model and compared the wind turbine response predicted by FAST v8, the corresponding FAST v7 results, and results from other participants in the OC4 project. We found good agreement between FAST v7 and FAST v8 when using the linear radiation/diffraction modeling approach. The strip-theory-based approach inherently differs from the radiation/diffraction approach used in FAST v7 and we identified and characterized the differences. Enabling the second-order effects significantly improved the agreement between FAST v8 and the other OC4 participants.

  2. Design and characterization of cefuroxime axetil biphasic floating minitablets.

    PubMed

    Jammula, Sruti; Patra, Ch Niranjan; Swain, Suryakanta; Panigrahi, Kanhu Charan; Nayak, Sabita; Dinda, Subas Chandra; Rao, Muddana Eswara Bhanoji

    2015-01-01

    Biphasic floating minitablets of cefuroxime axetil were prepared by melt granulation technique using two different grades of gelucire namely 50/13 and 43/01 to maintain constant plasma drug concentration. Loading dose of cefuroxime axetil was formulated as immediate release (IR) minitablets by using hydrophilic grade of gelucire 50/13. Maintenance dose was formulated as floating sustained release (SR) minitablets by using hydrophobic grade of gelucire 43/01. The prepared IR and SR granules were subjected to micromeritic studies and scanning electron microscopy. Fourier transform infrared spectroscopy (FT-IR) study revealed that drug and selected carriers were compatible. In vitro dissolution study of optimized IR minitablets showed more than 85% of loading dose dissolved within 30 min. Optimized SR minitablets showed zero lag time with floating duration more than 12 h. The drug release from SR minitablets was linear with square root of time with non-Fickian diffusion-controlled release. The optimized batch of minitablets was filled into 0 size hard gelatin capsule. In vitro dissolution study for capsule showed an immediate burst release followed by SR up to 12 h. There is no significant change in dissolution data after storage at 40 °C and 75% RH for three months. Microbiological assay of dissolution samples of optimized minitablets filled in capsules showed proportionate increase in inhibition of growth against Escherichia coli up to 12 h samples. In vivo bioavailability study in albino rabbits showed three times improvement in oral bioavailability. PMID:24417642

  3. Fabrication of mesoscopic floating Si wires by introducing dislocations

    NASA Astrophysics Data System (ADS)

    Motohashi, Mitsuya; Shimizu, Kazuya; Suzuki, Toshiaki; Niwa, Masaaki

    2014-12-01

    We fabricated a mesoscopic Si wire by introducing dislocations in a silicon wafer before HF anodization. The dislocations formed along the (111) crystal plane. The outline of the dislocation line was an inverted triangle. The resulting wire floated on a bridge girder and had a hybrid structure consisting of a porous layer and crystalline Si. The cross section of the wire had an inverted triangle shape. The wire formation mechanism is discussed in terms of carrier transport, crystal structure, and dislocation formation during anodization.

  4. Measurement of sheath thickness at a floating potential

    SciTech Connect

    Han, Hyung-Sik; Lee, Hyo-Chang; Oh, Se-Jin; Chung, Chin-Wook

    2014-02-15

    In a cylindrical Langmuir probe measurement, ion current is collected from the surface of the sheath surrounded at probe tip, not at the surface of the probe tip. By using this, the sheath thickness can be obtained, if we know some unknown parameters, such as ion current, plasma density, and electron temperature. In this paper, we present a method to measure sheath thickness by using a wave cutoff method and a floating harmonic method. The measured result is in a good agreement with Allen-Boyd-Reynolds theory.

  5. Porous-Floating-Gate Field-Effect Transistor

    NASA Technical Reports Server (NTRS)

    Thakoor, Anilkumar P.; Moopenn, Alexander W.; Lambe, John J.

    1990-01-01

    Porous-floating-gate, "vertical" field-effect transistor proposed as programmable analog memory device especially suitable for use in electronic neural networks. Analog value of electrical conductance of device represents synaptic weight (strength of synaptic connection) repeatedly modified by application of suitable writing or erasing voltage. Suited for hardware implementations of massively parallel neural-network architectures for two important reasons: vertical transistor structure requires only two external electrodes, and use of tailored amorphous semiconductors provides choice of very wide range of low conductivity values, dictated by overall power dissipation requirements in massively parallel neural-network circuits.

  6. Floating Probe Assembly for Measuring Temperature of Water

    NASA Technical Reports Server (NTRS)

    Stewart, Randy; Ruffin, Clyde

    2003-01-01

    A floating apparatus denoted a temperature probe aquatic suspension system (TPASS) has been developed for measuring the temperature of an ocean, lake, or other natural body of water at predetermined depths. These types of measurements are used in computer models to relate remotely sensed water-surface temperature to bulkwater temperature. Prior instruments built for the same purpose were found to give inaccurate readings because the apparatuses themselves significantly affected the temperatures of the water in their vicinities. The design of the TPASS is intended to satisfy a requirement to minimize the perturbation of the temperatures to be measured.

  7. Split ring floating air riding seal for a turbine

    DOEpatents

    Mills, Jacob A

    2015-11-03

    A floating air riding seal for a gas turbine engine with a rotor and a stator, an annular piston chamber with an axial moveable annular piston assembly within the annular piston chamber, an annular cavity formed on the annular piston assembly that faces a seal surface on the rotor, and a central passage connecting the annular cavity to the annular piston chamber to supply compressed air to the seal face, where the annular piston assembly is a split piston assembly to maintain a tight seal as coning of the rotor disk occurs.

  8. FLOAT OPERATED RADIAL GATE INSTALLATION. WASTEWAY NO. 1. WELLTONMOHAWK CANAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    FLOAT OPERATED RADIAL GATE INSTALLATION. WASTEWAY NO. 1. WELLTON-MOHAWK CANAL - STA. 99+23.50. United States Department of the Interior, Bureau of Reclamation; Gila Project, Arizona, Wellton-Mohawk Division. Drawing No. 50-D-2497, dated March 8, 1949, Denver Colorado. Sheet 1 of 7 - Wellton-Mohawk Irrigation System, Wasteway No. 1, Wellton-Mohawk Canal, North side of Wellton-Mohawk Canal, bounded by Gila River to North & the Union Pacific Railroad & Gila Mountains to south, Wellton, Yuma County, AZ

  9. FLOAT OPERATED RADIAL GATE HOIST ASSEMBLY LIST OF PARTS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    FLOAT OPERATED RADIAL GATE HOIST ASSEMBLY - LIST OF PARTS - BASE-CRANK. WASTEWAY NO. 1. WELLTON-MOHAWK CANAL - STA. 99+23.50. United States Department of the Interior, Bureau of Reclamation; Gila Project, Arizona, Wellton-Mohawk Division. Drawing No. 50-D-2511, dated May 3, 1949, Denver Colorado. Sheet 1 of 2 - Wellton-Mohawk Irrigation System, Wasteway No. 1, Wellton-Mohawk Canal, North side of Wellton-Mohawk Canal, bounded by Gila River to North & the Union Pacific Railroad & Gila Mountains to south, Wellton, Yuma County, AZ

  10. Rapid and medium setting high float bituminous emulsions

    SciTech Connect

    Schilling, P.; Schreuders, H.G.

    1987-06-30

    This patent describes a rapid set high float aqueous bituminous emulsion-comprising bitumen, water, and from about 0.4% to about 0.6%, based on the weight of the emulsion, of an anionic emulsifier comprised of an alkaline solution of a combination of (1) 20% to 80% fatty acids selected from the group consisting of tall oil fatty acids, tallow fatty acids, and mixtures. (2) 20% to 80% of a product of the reaction of the fatty acids with a member of the group consists of acrylic acid, methacrylic acid, fumaric acid, and maleic anhydride.

  11. High float and rapid setting anionic bituminous emulsions

    SciTech Connect

    Vanderzanden, E.J.

    1986-12-16

    This patent describes a high float and rapid setting bituminous emulsion comprising: (a) from about 50 to about 75 parts by weight of asphalt; (b) from about 0.01 to about 1.0 parts by weight of a carboxylic acid salt; (c) from about 0.2 to about 15 parts by weight of carboxylic acid esters; (d) sufficient base to provide the emulsion with a pH greater than about 9; and (e) sufficient water to make the total of (a), (b), (c), (d) and (e), equal 100 parts by weight.

  12. Scale Effect of Model in Seaplane-float Investigations

    NASA Technical Reports Server (NTRS)

    Sottorf, W

    1933-01-01

    For the purpose of solving all the problems involved, an investigation was made with flat, rectangular planing surfaces. The investigation of a flat, rectangular planing surface, which can be considered as the portion of a flat float bottom lying in front of the step, has the advantage that the frictional resistance can be determined directly from the test results. Normal and tangential forces act on the lower side of the planing surface towed through still water, while the upper side and the lateral edges are under constant atmospheric pressure.

  13. Coupled Dynamic Modeling of Floating Wind Turbine Systems: Preprint

    SciTech Connect

    Wayman, E. N.; Sclavounos, P. D.; Butterfield, S.; Jonkman, J.; Musial, W.

    2006-03-01

    This article presents a collaborative research program that the Massachusetts Institute of Technology (MIT) and the National Renewable Energy Laboratory (NREL) have undertaken to develop innovative and cost-effective floating and mooring systems for offshore wind turbines in water depths of 10-200 m. Methods for the coupled structural, hydrodynamic, and aerodynamic analysis of floating wind turbine systems are presented in the frequency domain. This analysis was conducted by coupling the aerodynamics and structural dynamics code FAST [4] developed at NREL with the wave load and response simulation code WAMIT (Wave Analysis at MIT) [15] developed at MIT. Analysis tools were developed to consider coupled interactions between the wind turbine and the floating system. These include the gyroscopic loads of the wind turbine rotor on the tower and floater, the aerodynamic damping introduced by the wind turbine rotor, the hydrodynamic damping introduced by wave-body interactions, and the hydrodynamic forces caused by wave excitation. Analyses were conducted for two floater concepts coupled with the NREL 5-MW Offshore Baseline wind turbine in water depths of 10-200 m: the MIT/NREL Shallow Drafted Barge (SDB) and the MIT/NREL Tension Leg Platform (TLP). These concepts were chosen to represent two different methods of achieving stability to identify differences in performance and cost of the different stability methods. The static and dynamic analyses of these structures evaluate the systems' responses to wave excitation at a range of frequencies, the systems' natural frequencies, and the standard deviations of the systems' motions in each degree of freedom in various wind and wave environments. This article in various wind and wave environments. This article explores the effects of coupling the wind turbine with the floating platform, the effects of water depth, and the effects of wind speed on the systems' performance. An economic feasibility analysis of the two concepts

  14. Finger rafting: a generic instability of floating elastic sheets.

    PubMed

    Vella, Dominic; Wettlaufer, J S

    2007-02-23

    Colliding ice floes are often observed to form a series of interlocking fingers. We show that this striking phenomenon is not a result of some peculiar property of ice but rather a general and robust mechanical phenomenon reproducible in the laboratory with other floating materials. We determine the theoretical relationship between the width of the resulting fingers and the material's mechanical properties and present experimental results along with field observations to support the theory. The generality of this "finger rafting" suggests that analogous processes may be responsible for creating the large-scale structures observed at the boundaries between Earth's convergent tectonic plates. PMID:17359135

  15. Microstructure and levitation properties of floating zone melted YBCO samples

    SciTech Connect

    Bashkirov, Yu.A.; Fleishman, L.S.; Vdovin, A.B.; Zubritsky, I.A.; Smirnov, V.V.; Vinogradov, A.V.

    1994-07-01

    Radiation zone melting has been used to produce texture in sintered YBCO cylindrical samples. Microstructural analysis by electron microscopy and pole figure measurements reveals that the production process gives rise to a preferential orientation within large domains. D.C. transport measurements show that changes in alignment orientation can result in the inability to carry a transport current. Both a.c. magnetic field shielding and levitation properties are substantially improved by the floating zone melting, the levitation force being increased with the texture domain size growth.

  16. Observations of the Faroe Bank Channel overflow using bottom-following RAFOS floats

    NASA Astrophysics Data System (ADS)

    Prater, Mark D.; Rossby, Tom

    2005-02-01

    Overflows do not easily lend themselves to study by Lagrangian floats that remain on a constant isobaric (pressure) or isopycnal (density) surface, since the mixing, entrainment, and descent of an overflow plume result in an increase of the pressure and typically a decrease in the density of the overflow waters. A simple technique to maintain the float's altitude above the bottom was developed, and 12 "bottom-following" RAFOS floats were deployed at or downstream of the sill in the Faroe Bank Channel in the summer of 2000 from the R.S.S. Discovery. A technical problem resulted in the majority of the floats becoming stuck to the bottom; nevertheless several floats were able to traverse the Iceland Basin and surface near the southeastern slope of Iceland. These floats made a descent from the mouth of the Faroe Bank Channel, only to shoal along the southern slope of the Iceland-Faroe Ridge before descending again when passing through the northwest corner of the Iceland Basin. Typical current speeds through the Basin were 0.20- 0.30ms-1, with peaks of 0.40- 0.50ms-1. Although the floats that were stuck on the bottom provided no trajectory information, they were able to provide a time-series of bottom or near-bottom temperature. In addition, a crude estimate of the flow regime could be made by interpreting the pressure signals from these stuck floats as a response to strong or weak currents. Floats that were bottom stuck near the mouth of the Channel experienced large fluctuations in temperature ( 0- 5C) and height of the bottom (and thus presumably speed) on scales from 1 to 4 days. Another float stuck 100 km downstream of the sill underwent temperature and speed excursions on similar time scales, albeit over a smaller range. The behavior of the floats is assumed to be the result of the mesoscale variability of the overflow plume downstream of the Faroe Bank Channel.

  17. Development and in vitro evaluation of novel floating chitosan microcapsules for oral use: comparison with non-floating chitosan microspheres.

    PubMed

    El-Gibaly, Ibrahim

    2002-12-01

    Floating (F) microcapsules containing melatonin (MT) were prepared by the ionic interaction of chitosan and a negatively charged surfactant, sodium dioctyl sulfosuccinate (DOS). The DOS/chitosan complex formation was confirmed employing infrared spectroscopy, differential scanning calorimetry (DSC), solubility and X-ray diffraction analysis. The characteristics of the F microcapsules generated compared with the conventional non-floating (NF) microspheres manufactured from chitosan and sodium tripolyphosphate (TPP) were also investigated. The effect of various factors (crosslinking time, DOS and chitosan concentrations, as well as drug/polymer ratio) on microcapsule properties were evaluated. The use of DOS solution in coagulation of chitosan produced well-formed microcapsules with round hollow core and 31.2-59.74% incorporation efficiencies. Chitosan concentration and drug/polymer ratio had a remarkable effect on drug entrapment in DOS/chitosan microcapsules. The dissolution profiles of most of microcapsules showed near zero order kinetics in simulated gastric fluid (S.G.F: pH 1.2). Moreover, release of the drug from these microcapsules was greatly retarded with release lasting for several hours (t(50%) (S.G.F.): 1.75-6.7 h, depending on processing factors), compared with NF microspheres where drug release was almost instant. Most of the hollow microcapsules developed tended to float over simulated biofluids for more than 12 h. Swelling studies conducted on various drug-free formulations, clearly indicated that DOS/chitosan microcapsules showed less swelling and no dissolution in S.G.F. for more than 3 days, whereas, TPP/chitosan microspheres were markedly swollen and lost their integrity in S.G.F. within 5 h. Therefore, data obtained suggest that the F hollow microcapsules produced would be an interesting gastroretentive controlled-release delivery system for drugs. PMID:12433430

  18. Multi-modal two-step floating catchment area analysis of primary health care accessibility.

    PubMed

    Langford, Mitchel; Higgs, Gary; Fry, Richard

    2016-03-01

    Two-step floating catchment area (2SFCA) techniques are popular for measuring potential geographical accessibility to health care services. This paper proposes methodological enhancements to increase the sophistication of the 2SFCA methodology by incorporating both public and private transport modes using dedicated network datasets. The proposed model yields separate accessibility scores for each modal group at each demand point to better reflect the differential accessibility levels experienced by each cohort. An empirical study of primary health care facilities in South Wales, UK, is used to illustrate the approach. Outcomes suggest the bus-riding cohort of each census tract experience much lower accessibility levels than those estimated by an undifferentiated (car-only) model. Car drivers' accessibility may also be misrepresented in an undifferentiated model because they potentially profit from the lower demand placed upon service provision points by bus riders. The ability to specify independent catchment sizes for each cohort in the multi-modal model allows aspects of preparedness to travel to be investigated. PMID:26798964

  19. Feasibility of Floating Platform Systems for Wind Turbines: Preprint

    SciTech Connect

    Musial, W.; Butterfield, S.; Boone, A.

    2003-11-01

    This paper provides a general technical description of several types of floating platforms for wind turbines. Platform topologies are classified into multiple- or single-turbine floaters and by mooring method. Platforms using catenary mooring systems are contrasted to vertical mooring systems and the advantages and disadvantages are discussed. Specific anchor types are described in detail. A rough cost comparison is performed for two different platform architectures using a generic 5-MW wind turbine. One platform is a Dutch study of a tri-floater platform using a catenary mooring system, and the other is a mono-column tension-leg platform developed at the National Renewable Energy Laboratory. Cost estimates showed that single unit production cost is $7.1 M for the Dutch tri-floater, and $6.5 M for the NREL TLP concept. However, value engineering, multiple unit series production, and platform/turbine system optimization can lower the unit platform costs to $4.26 M and $2.88 M, respectively, with significant potential to reduce cost further with system optimization. These foundation costs are within the range necessary to bring the cost of energy down to the DOE target range of $0.05/kWh for large-scale deployment of offshore floating wind turbines.

  20. Capillary Forces between Floating Objects: Superhydrophobic Surfaces Provide Mechanistic Insight

    NASA Astrophysics Data System (ADS)

    Zhang, Minchao; McCarthy, Thomas J.; Crosby, Alfred J.

    When two floating objects are close, they will either move towards or away from one another to minimize the energy caused by the overlap of the liquid/air interfacial deformations. Capillary forces cause these behaviors, but directly relating the interfacial deformations and the capillary interactions hasn't been explored experimentally. We choose a liquid marble, which has a superhydrophobic surface, as a free floating object and a fixed ``wall'' with carefully controlled contact angle as another object to generate two deformations at the interface. When the liquid marble is close to the wall, the two deformations interact, causing changes in the Laplace pressure at the interface and a reconfiguration of the interface. In response, the liquid marble moves either towards or away from the wall. Using image analysis of videos recording the liquid marble position as a function of time, we measured the liquid marble to wall distance and determine the spatio-temporal relationships. Furthermore, capillary forces were calculated from the velocities and accelerations. Based on this data, we present a new explanation for the capillary interactions from the perspective of Laplace pressure changing induced the reconfiguration of the interfacial deformations.

  1. Geometry-driven folding transitions in floating thin films

    NASA Astrophysics Data System (ADS)

    Paulsen, Joseph D.; Démery, Vincent; Toga, K. Bugra; Qiu, Zhanlong; Davidovitch, Benny; Russell, Thomas P.; Menon, Narayanan

    When a thin elastic sheet is compressed, it forms wrinkles to gather excess material, while deforming the fluid or solid substrate by only a small amount. Upon further compression, the sheet may fold, in order to lower the mechanical energy of the system1. Here we demonstrate a folding transition that is independent of the mechanical properties of the sheet. We study the deformations of a thin polymer film that has an annular shape, floating on a planar air-water interface. By controlling the concentration of a surfactant outside the film, we vary the tension pulling on the outer boundary of the annulus. The sheet spontaneously folds at a threshold ratio of inner to outer surface tension that depends on the geometry of the sheet, but is independent of its bending rigidity. Our results are consistent with a simple geometric principle: the sheet adopts the unstretched shape that minimizes the interfacial energy of the exposed liquid2. Finally, we consider the application of this geometric principle to the folding of a floating indented film.1. Pocivavsek et al., Science 320, 912 (2008).2. Paulsen et al., Nature Materials, doi:10.1038/nmat4397 (2015).

  2. Floating Escherichia coli by expressing cyanobacterial gas vesicle genes

    NASA Astrophysics Data System (ADS)

    Wang, Tianhe; Kang, Li; Li, Jiaheng; Wu, Wenjie; Zhang, Peiran; Gong, Minghao; Lai, Weihong; Zhang, Chunyan; Chang, Lei; Peng, Yong; Yang, Zhongzhou; Li, Lian; Bao, Yingying; Xu, Haowen; Zhang, Xiaohua; Sui, Zhenghong; Yang, Guanpin; Wang, Xianghong

    2015-02-01

    Gas vesicles are hollow, air-filled polyprotein structures that provide the buoyancy to cells. They are found in a variety of prokaryotes. In this study, we isolated a partial gas vesicle protein gene cluster containing gvpA and gvpC20Ψ from Planktothrix rubescens, and inserted it into an expression vector and expressed it in E. coli. The gas vesicle was developed in bacterial cells, which made bacterial cells to float on medium surface. We also amplified gvpA and gvpC20Ψ separately and synthesized an artificial operon by fusing these two genes with the standardized gene expression controlling elements of E. coli. The artificial operon was expressed in E. coli, forming gas vesicles and floating bacteria cells. Our findings verified that the whole set of genes and the overall structure of gas vesicle gene cluster are not necessary for developing gas vesicles in bacteria cells. Two genes, gvpA and gvpC20Ψ, of the gas vesicle gene cluster are sufficient for synthesizing an artificial operon that can develop gas vesicles in bacteria cells. Our findings provided a wide range of applications including easing the harvest of cultured microalgae and bacteria, as well as enriching and remediating aquatic pollutants by constructing gas vesicles in their cells.

  3. On the mechanism of floating and sliding of liquid marbles.

    PubMed

    Bormashenko, Edward; Bormashenko, Yelena; Musin, Albina; Barkay, Zahava

    2009-03-01

    The mechanisms of floating and sliding of liquid marbles are studied. Liquid marbles containing CaCl(2) and marbles containing NaOH water solutions float on water containing Na(2)CO(3) and an alcoholic solution of phenolphthalein with no chemical reaction. Sliding of liquid marbles, consisting of NaOH water solutions, on polymer substrates coated with phenolphthalein is studied as well. No chemical reaction is observed. These observations supply direct experimental evidence for the suggestion that interfaces are separated by an air layer when marbles roll on solid substrates. It is concluded that a liquid marble rests on hydrophobic particles coating the liquid. In contrast, drops containing an NaOH water solution sliding on superhydrophobic surfaces coated with phenolphthalein leave a colored trace. The mechanism of low-friction sliding of drops deposited on superhydrophobic surfaces and liquid marbles turns out to be quite different: there is no direct contact between liquid and solid in the case of marbles' motion. PMID:19177484

  4. Numerical simulations of inductive-heated float-zone growth

    NASA Technical Reports Server (NTRS)

    Chan, Y. T.; Choi, S. K.

    1992-01-01

    The present work provides an improved fluid flow and heat-transfer modeling of float-zone growth by introducing a RF heating model so that an ad hoc heating temperature profile is not necessary. Numerical simulations were carried out to study the high-temperature float-zone growth of titanium carbide single crystal. The numerical results showed that the thermocapillary convection occurring inside the molten zone tends to increase the convexity of the melt-crystal interface and decrease the maximum temperature of the molten zone, while the natural convection tends to reduce the stability of the molten zone by increasing its height. It was found that the increase of induced heating due to the increase of applied RF voltage is reduced by the decrease of zone diameter. Surface tension plays an important role in controlling the amount of induced heating. Finally, a comparison of the computed shape of the free surface with a digital image obtained during a growth run showed adequate agreement.

  5. Bread board float zone experiment system for high purity silicon

    NASA Technical Reports Server (NTRS)

    Kern, E. L.; Gill, G. L., Jr.

    1982-01-01

    A breadboard float zone experimental system has been established at Westech Systems for use by NASA in the float zone experimental area. A used zoner of suitable size and flexibility was acquired and installed with the necessary utilities. Repairs, alignments and modifications were made to provide for dislocation free zoning of silicon. The zoner is capable of studying process parameters used in growing silicon in gravity and is flexible to allow trying of new features that will test concepts of zoning in microgravity. Characterizing the state of the art molten zones of a growing silicon crystal will establish the data base against which improvements of zoning in gravity or growing in microgravity can be compared. 25 mm diameter was chosen as the reference size, since growth in microgravity will be at that diameter or smaller for about the next 6 years. Dislocation free crystals were growtn in the 100 and 111 orientations, using a wide set of growth conditions. The zone shape at one set of conditions was measured, by simultaneously aluminum doping and freezing the zone, lengthwise slabbing and delineating by etching. The whole set of crystals, grown under various conditions, were slabbed, polished and striation etched, revealing the growth interface shape and the periodic and aperiodic natures of the striations.

  6. The floating cardiac fat pad-sign of occult pneumothorax.

    PubMed

    Kaufman, Claire; Bokhari, S A Jamal

    2016-08-01

    Pneumothoraces are a possible sequela of chest trauma with potential morbidity and mortality if not recognized and treated promptly. A portable supine chest radiograph is frequently the first radiologic study performed in the setting of trauma. While large pneumothoraces can be readily recognized on these radiographs, smaller pneumothoraces are missed in up to 15 % of trauma patients. There are many radiographic signs of occult pneumothoraces, and we are presenting a new radiographic sign of occult pneumothorax. The floating cardiac fat pad sign occurs when pleural air collects anteriorly and superiorly in the most non-dependent portion of the chest lifting the pericardial fat pad off the diaphragm. Lung markings are still seen surrounding the pericardial fat pad due to the inflated lower lobe of the lung resting dependently. Rapid and accurate identification of pneumothoraces is critical but often difficult on chest radiographs. Although there are many existing radiographic signs for identification of pneumothorax, prospective identification of small pneumothoraces is still relatively poor. Here, we describe an additional sign which aides in the detection of pneumothoraces, the floating cardiac fat pad. When present, this should prompt further evaluation with chest CT or upright chest radiograph. PMID:27250975

  7. Fragility of Floating Docks for Small Craft Marinas

    NASA Astrophysics Data System (ADS)

    Keen, A.; Eskijian, M.; Lynett, P. J.; Ayca, A.

    2015-12-01

    Because of the damage resulting from the 2010 Chile and 2011 Japanese tele-tsunamis, damage to the small craft marinas in California has become an important concern. This paper will explain the methodology and results used to simulate the demand and also the structural capacity of the floating dock system, composed of floating docks, fingers and moored vessels during tsunami events. The intent is to develop a predictive tool to understand the vulnerability of California's small craft harbors to tsunami events. To validate the methodology, the probabilistic model will be applied to Santa Cruz Harbor. Maps of maximum velocity and mean current direction from the 2011 Japan tsunami have been developed using a numerical model. Cleat and pile guide locations will be recorded and georeferenced from aerial images before the event. The fragility curves for each dock/finger system will be compared with damage reports and aerial images from just after the tsunami event. A discussion of how the fragility curves compare with the damage reports will be included. It is anticipated that these curves will be useful to marina operators to use as a tool to determine where rehabilitation might be necessary to mitigate some of the damage from the next event. Conclusions will focus on how results can be used by marina operators to reduce harbor vulnerability to tsunamis.

  8. System for deflection measurements of floating dry docks

    NASA Astrophysics Data System (ADS)

    Gorbachev, Alexey A.; Pantyushin, Anton V.; Serikova, Mariya G.; Korotaev, Valery V.; Timofeev, Aleksandr N.

    2015-05-01

    In this paper we introduce a system for deflection measurement of floating dry docks. The system contains two measurement channels observing opposite directions of the dock. It also includes set of reference marks, an industrial computer and a display. Each channel contains CMOS camera with long focal-length lens. Reference marks are implemented as IR LED arrays with 940 nm working wavelength for better performance within bad weather conditions (e.g. fog, rain, high humidity etc.). In the paper we demonstrate results of an analysis of different optical schemes for coupling the oppositely directed channels of the measurement unit and show that the scheme with two image sensors with separated lenses is an optimal option, because it allows usage of nonequidistant location of reference marks and demonstrates the least value of parasitic shift caused by rotations of the measuring unit. The developed system was tested both on specially-designed setup and in real infrastructure of a floating dry dock. The conducted tests proved that a measuring error of the system is smaller than +/- 1.5 mm within the measurement range of +/- 150 mm when deflection of 100 m dock is measured. Obtained results showed that the system demonstrates an ability to work in a harsh environment including poor weather conditions.

  9. Nonlinear dynamic behaviors of a floating structure in focused waves

    NASA Astrophysics Data System (ADS)

    Cao, Fei-feng; Zhao, Xi-zeng

    2015-12-01

    Floating structures are commonly seen in coastal and offshore engineering. They are often subjected to extreme waves and, therefore, their nonlinear dynamic behaviors are of great concern. In this paper, an in-house CFD code is developed to investigate the accurate prediction of nonlinear dynamic behaviors of a two-dimensional (2-D) box-shaped floating structure in focused waves. Computations are performed by an enhanced Constrained Interpolation Profile (CIP)-based Cartesian grid model, in which a more accurate VOF (Volume of Fluid) method, the THINC/SW scheme (THINC: tangent of hyperbola for interface capturing; SW: Slope Weighting), is used for interface capturing. A focusing wave theory is used for the focused wave generation. The wave component of constant steepness is chosen. Comparisons between predictions and physical measurements show good agreement including body motions and free surface profiles. Although the overall agreement is good, some discrepancies are observed for impact pressure on the superstructure due to water on deck. The effect of grid resolution on the results is checked. With a fine grid, no obvious improvement is seen in the global body motions and impact pressures due to water on deck. It is concluded that highly nonlinear phenomena, such as distorted free surface, large-amplitude body motions, and violent impact flow, have been predicted successfully.

  10. Underwater and Floating-Leaved Plants of the United States and Canada.

    ERIC Educational Resources Information Center

    Hotchkiss, Neil

    This is the third in a series of guides to the field identification of North American marsh and water plants. Described are plants which have foliage habitually under water or floating, or which have underwater or floating forms, and which have characteristics by which they can be distinguished with the naked eye. Where genera or species cannot be…

  11. Development and Characterization of Novel Floating-Mucoadhesive Tablets Bearing Venlafaxine Hydrochloride

    PubMed Central

    Misra, Raghvendra

    2016-01-01

    The present investigation is concerned about the development of floating bioadhesive drug delivery system of venlafaxine hydrochloride which after oral administration exhibits a unique combination of floating and bioadhesion to prolong gastric residence time and increase drug bioavailability within the stomach. The floating bioadhesive tablets were prepared by the wet granulation method using different ratios of hydroxypropyl methyl cellulose (HPMC K4MCR) and Carbopol 934PNF as polymers. Sodium bicarbonate (NaHCO3) and citric acid were used as gas (CO2) generating agents. Tablets were characterized for floating properties, in vitro drug release, detachment force, and swelling index. The concentration of hydroxypropyl methyl cellulose and Carbopol 934PNF significantly affects the in vitro drug release, floating properties, detachment force, and swelling properties of the tablets. The optimized formulation showed the floating lag time 72 ± 2.49 seconds and duration of floating 24.50 ± 0.74 hr. The in vitro release studies and floating behavior were studied in simulated gastric fluid (SGF) at pH 1.2. Different drug release kinetics models were also applied. The in vitro drug release from tablets was sufficiently sustained (more than 18 hr) and the Fickian transports of the drug from the tablets were confirmed. The radiological evidence suggests that the tablets remained buoyant and altered position in the stomach of albino rabbit and mean gastric residence time was prolonged (more than > 6 hr). PMID:27274884

  12. Water rolling and floating upon water: marbles supported by a water/marble interface.

    PubMed

    Bormashenko, Edward; Bormashenko, Yelena; Musin, Albina

    2009-05-01

    Floating of liquid marbles on a water/air interface was studied. The critical density allowing floating marbles containing NaCl solution was established experimentally and compared with its calculated value. A satisfactory agreement between experimental and theoretical values of the critical density is reported. PMID:19251263

  13. 14 CFR 23.527 - Hull and main float load factors.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Hull and main float load factors. 23.527... Water Loads § 23.527 Hull and main float load factors. (a) Water reaction load factors nw must be...=seaplane landing weight in pounds. (6) K1=empirical hull station weighing factor, in accordance with...

  14. 14 CFR 23.527 - Hull and main float load factors.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Hull and main float load factors. 23.527... Water Loads § 23.527 Hull and main float load factors. (a) Water reaction load factors nw must be...=seaplane landing weight in pounds. (6) K1=empirical hull station weighing factor, in accordance with...

  15. 14 CFR 23.527 - Hull and main float load factors.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Hull and main float load factors. 23.527... Water Loads § 23.527 Hull and main float load factors. (a) Water reaction load factors nw must be...=seaplane landing weight in pounds. (6) K1=empirical hull station weighing factor, in accordance with...

  16. 14 CFR 23.527 - Hull and main float load factors.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Hull and main float load factors. 23.527... Water Loads § 23.527 Hull and main float load factors. (a) Water reaction load factors nw must be...=seaplane landing weight in pounds. (6) K1=empirical hull station weighing factor, in accordance with...

  17. Definition of the Semisubmersible Floating System for Phase II of OC4

    SciTech Connect

    Robertson, A.; Jonkman, J.; Masciola, M.; Song, H.; Goupee, A.; Coulling, A.; Luan, C.

    2014-09-01

    Phase II of the Offshore Code Comparison Collaboration Continuation (OC4) project involved modeling of a semisubmersible floating offshore wind system as shown below. This report documents the specifications of the floating system, which were needed by the OC4 participants for building aero-hydro-servo-elastic models.

  18. Definition of the Floating System for Phase IV of OC3

    SciTech Connect

    Jonkman, J.

    2010-05-01

    Phase IV of the IEA Annex XXIII Offshore Code Comparison Collaboration (OC3) involves the modeling of an offshore floating wind turbine. This report documents the specifications of the floating system, which are needed by the OC3 participants for building aero-hydro-servo-elastic models.

  19. 46 CFR 180.137 - Stowage of life floats and buoyant apparatus.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Stowage of life floats and buoyant apparatus. 180.137 Section 180.137 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) LIFESAVING EQUIPMENT AND ARRANGEMENTS Survival Craft Arrangements and Equipment § 180.137 Stowage of life floats...

  20. Children's Knowledge of Hierarchical Phrase Structure: Quantifier Floating in Japanese

    ERIC Educational Resources Information Center

    Suzuki, Takaaki; Yoshinaga, Naoko

    2013-01-01

    The interpretation of floating quantifiers in Japanese requires knowledge of hierarchical phrase structure. However, the input to children is insufficient or even misleading, as our analysis indicates. This presents an intriguing question on learnability: do children interpret floating quantifiers based on a structure-dependent rule which is not…

  1. 49 CFR 1242.44 - Trucks, trailers, and containers (revenue service) and floating equipment (revenue service...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 9 2011-10-01 2011-10-01 false Trucks, trailers, and containers (revenue service) and floating equipment (revenue service) (accounts XX-23-43 and XX-23-44). 1242.44 Section 1242.44... Trucks, trailers, and containers (revenue service) and floating equipment (revenue service) (accounts...

  2. 46 CFR 160.027-3 - Additional requirements for life floats.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... breaking strength of at least 1600 N (355 lb.). The netting must be constructed on not more than 5 cm (2 in... use. (f) The platform must be suspended from the body of the float by a net or an equivalent... center of the float body. (1) The net must be constructed of cordage with a minimum breaking strength...

  3. 46 CFR 160.027-3 - Additional requirements for life floats.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... breaking strength of at least 1600 N (355 lb.). The netting must be constructed on not more than 5 cm (2 in... use. (f) The platform must be suspended from the body of the float by a net or an equivalent... center of the float body. (1) The net must be constructed of cordage with a minimum breaking strength...

  4. 46 CFR 160.027-3 - Additional requirements for life floats.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... breaking strength of at least 1600 N (355 lb.). The netting must be constructed on not more than 5 cm (2 in... use. (f) The platform must be suspended from the body of the float by a net or an equivalent... center of the float body. (1) The net must be constructed of cordage with a minimum breaking strength...

  5. 49 CFR 1242.44 - Trucks, trailers, and containers (revenue service) and floating equipment (revenue service...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Trucks, trailers, and containers (revenue service) and floating equipment (revenue service) (accounts XX-23-43 and XX-23-44). 1242.44 Section 1242.44... Trucks, trailers, and containers (revenue service) and floating equipment (revenue service) (accounts...

  6. Evaluation of porous carrier-based floating orlistat microspheres for gastric delivery.

    PubMed

    Jain, Sunil K; Agrawal, Govind P; Jain, Narendra K

    2006-01-01

    The purpose of this research was to prepare floating microspheres consisting of (1) calcium silicate as porous carrier; (2) orlistat, an oral anti-obesity agent; and (3) Eudragit S as polymer, by solvent evaporation method and to evaluate their gastro-retentive and controlled-release properties. The effect of various formulation and process variables on the particle morphology, micromeritic properties, in vitro floating behavior, percentage drug entrapment, and in vitro drug release was studied. The gamma scintigraphy of the optimized formulation was performed in albino rabbits to monitor the transit of floating microspheres in the gastrointestinal tract. The orlistat-loaded optimized formulation was orally administered to albino rabbits, and blood samples collected were used to determine pharmacokinetic parameters of orlistat from floating microspheres. The microspheres were found to be regular in shape and highly porous. Microsphere formulation CS4, containing 200 mg calcium silicate, showed the best floating ability (88% +/- 4% buoyancy) in simulated gastric fluid as compared with other formulations. Release pattern of orlistat in simulated gastric fluid from all floating microspheres followed Higuchi matrix model and Peppas-Korsmeyer model. Prolonged gastric residence time of over 6 hours was achieved in all rabbits for calcium silicate-based floating microspheres of orlistat. The enhanced elimination half-life observed after pharmacokinetic investigations in the present study is due to the floating nature of the designed formulations. PMID:17233542

  7. Changing Patterns of the Floating Population in China during 2000-2010*

    PubMed Central

    Liang, Zai; Li, Zhen; Ma, Zhongdong

    2015-01-01

    Using data from the 2000 and 2010 Chinese Population Censuses and applying a consistent definition of migration, this paper examines changing patterns of China's floating population during 2000-2010. We find that during the first decade of the 21st century, there have been significant changes in China's floating population, as reflected in continuing rise of interprovincial floating population and the rise of the floating population in China's western and interior regions, geographic diversification of destinations for the floating population, a major increase in interprovincial return migration, and significant improvement in education and occupational profiles among the floating population. We argue that these patterns are driven by a combination of complex domestic and international factors, including the newly released Labor Law, removal of agricultural tax, the western China development program, increased investment in education by the Chinese government, and the global financial crisis. We also discuss several challenges facing the floating population in the coming years, which include equality of educational opportunity for migrant children and adequate housing and social welfare protection for the floating population. Finally, we reflect on the future of migration research in China. PMID:26213427

  8. Students' Views of Floating & Sinking. Learning in Science Project (Primary). Working Paper No. 116.

    ERIC Educational Resources Information Center

    Biddulph, Fred

    This study investigated the meanings and ideas held and questions asked by children (ages 7-14) about floating and sinking (in water). Data were collected from interviews using "interview-about-instances" (IAI) cards (included in an appendix) and 10 objects which either floated or sank. Additional data were collected from classroom surveys and…

  9. Payload specialist Sultan Salman Abdelazize Al-Saud floats over pilots chair

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Payload specialist Sultan Salman Abdelazize Al-Saud floats above the pilot's station on Discovery's forward flight deck. On one side of him floats a clipboard, on the other side a fire extinguisher is attached to the wall. Through overhead windows beyond him are seen reflections of the Earth's horizon.

  10. Development and Characterization of Novel Floating-Mucoadhesive Tablets Bearing Venlafaxine Hydrochloride.

    PubMed

    Misra, Raghvendra; Bhardwaj, Peeyush

    2016-01-01

    The present investigation is concerned about the development of floating bioadhesive drug delivery system of venlafaxine hydrochloride which after oral administration exhibits a unique combination of floating and bioadhesion to prolong gastric residence time and increase drug bioavailability within the stomach. The floating bioadhesive tablets were prepared by the wet granulation method using different ratios of hydroxypropyl methyl cellulose (HPMC K4MCR) and Carbopol 934PNF as polymers. Sodium bicarbonate (NaHCO3) and citric acid were used as gas (CO2) generating agents. Tablets were characterized for floating properties, in vitro drug release, detachment force, and swelling index. The concentration of hydroxypropyl methyl cellulose and Carbopol 934PNF significantly affects the in vitro drug release, floating properties, detachment force, and swelling properties of the tablets. The optimized formulation showed the floating lag time 72 ± 2.49 seconds and duration of floating 24.50 ± 0.74 hr. The in vitro release studies and floating behavior were studied in simulated gastric fluid (SGF) at pH 1.2. Different drug release kinetics models were also applied. The in vitro drug release from tablets was sufficiently sustained (more than 18 hr) and the Fickian transports of the drug from the tablets were confirmed. The radiological evidence suggests that the tablets remained buoyant and altered position in the stomach of albino rabbit and mean gastric residence time was prolonged (more than > 6 hr). PMID:27274884

  11. 40 CFR 65.43 - Fixed roof with an internal floating roof (IFR).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 16 2012-07-01 2012-07-01 false Fixed roof with an internal floating roof (IFR). 65.43 Section 65.43 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... internal floating roof (IFR). (a) IFR design requirements. The owner or operator who elects to...

  12. 40 CFR 65.43 - Fixed roof with an internal floating roof (IFR).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Fixed roof with an internal floating roof (IFR). 65.43 Section 65.43 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... internal floating roof (IFR). (a) IFR design requirements. The owner or operator who elects to...

  13. 40 CFR 65.43 - Fixed roof with an internal floating roof (IFR).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 16 2014-07-01 2014-07-01 false Fixed roof with an internal floating roof (IFR). 65.43 Section 65.43 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... internal floating roof (IFR). (a) IFR design requirements. The owner or operator who elects to...

  14. 40 CFR 65.43 - Fixed roof with an internal floating roof (IFR).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 16 2013-07-01 2013-07-01 false Fixed roof with an internal floating roof (IFR). 65.43 Section 65.43 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... internal floating roof (IFR). (a) IFR design requirements. The owner or operator who elects to...

  15. A Descriptive Study of Pre-Service Science Teachers' Misconceptions about Sinking-Floating

    ERIC Educational Resources Information Center

    Kiray, Seyit Ahmet; Aktan, Filiz; Kaynar, Hamza; Kilinc, Sena; Gorkemli, Tugce

    2015-01-01

    The purpose of this study is twofold. Firstly, it attempts to determine the pre-service science teachers' misconceptions about floating and sinking. Secondly, it aims to reveal the level of pre-service science teachers' misconceptions, scientific knowledge, lack of knowledge, and lack of confidence related to floating and sinking. To conduct the…

  16. Radiological Control of the Floating Mass Transducer Attached to the Round Window

    PubMed Central

    Rademacher, G.; Wagner, J.; Mittmann, P.; Basta, Dietmar; Ernst, Arne

    2013-01-01

    The surgical rehabilitation of mixed hearing losses can be performed by coupling the floating mass transducer of the Vibrant Soundbridge to the round window. The quality of coupling the floating mass transducer to the round window is crucial for the audiological outcome. It was the aim of this study to further observe the different patterns of floating mass transducer position at the round window. We compared twenty patients with mixed hearing loss implanted with a floating mass transducer attached to the round window and 24 surgeries between 5/2007 and 6/2010. An evaluation of the chronological observation of the flat panel angiography-controlled position of the floating mass transducer at the round window with relation to the surgical report and the audiological outcome was done. We observed no changes in the mean pre- and postbone conduction thresholds. The floating mass transducer position was variable and could be radiologically classified and correlated with the audiologically outcome. A learning curve was observed from the earlier to later implantations. Postoperative, radiological evaluation of the location and angle of the floating mass transducer by means of flat panel tomography allowed us to classify the floating mass transducer position at the round window into 4 groups. PMID:24327808

  17. New levodopa sustained-release floating minitablets coated with insoluble acrylic polymer.

    PubMed

    Goole, J; Deleuze, Ph; Vanderbist, F; Amighi, K

    2008-02-01

    The aim of this study was to develop a new coated multiple-unit sustained-release floating system that is able to float over an extended period of time. Levodopa was used as a model drug. The system consisted of a 3mm drug-containing gas-generating core, prepared by melt granulation and subsequent compression, and coated with a flexible polymeric membrane. Eudragit RL30D and ATEC were used as a film former and a plasticizer, respectively. The coating level was fixed at 20% (w/w). The floating lag time decreased as the proportion of effervescent agents increased. The optimized coated floating minitablets could float within 20min and remained buoyant for more than 13h. In addition, a sustained release of levodopa for more than 20h was observed. PMID:17804212

  18. Floating microspheres of valacyclovir HCl: Formulation, optimization, characterization, in vitro and in vivo floatability studies

    PubMed Central

    Goswami, Nilamgiri; Joshi, Garima; Sawant, Krutika

    2012-01-01

    Floating microspheres are multiple unit Gastroretentive drug delivery systems. Valacyclovir hydrochloride (VCH) is L-valyl ester prodrug of acyclovir. VCH degrades in intestinal fluid. The objective was to develop floating microspheres of VCH to localise the drug at upper part of GIT, for improved absorption. Floating microspheres were prepared by W/O emulsification solvent evaporation method using Ethylcellulose (EC) as polymer. Particle size and % EE were 550.021±0.241 μm, 79.88±2.236% respectively. in vitro and in vivo floatability studies confirmed floating behaviour of microspheres. VCH loaded floating microspheres can be a suitable alternative to the conventional formulation, by localizing the drug at upper GIT. PMID:23066217

  19. Current-Sensitive Path Planning for an Underactuated Free-Floating Ocean Sensorweb

    NASA Technical Reports Server (NTRS)

    Dahl, Kristen P.; Thompson, David R.; McLaren, David; Chao, Yi; Chien, Steve

    2011-01-01

    This work investigates multi-agent path planning in strong, dynamic currents using thousands of highly under-actuated vehicles. We address the specific task of path planning for a global network of ocean-observing floats. These submersibles are typified by the Argo global network consisting of over 3000 sensor platforms. They can control their buoyancy to float at depth for data collection or rise to the surface for satellite communications. Currently, floats drift at a constant depth regardless of the local currents. However, accurate current forecasts have become available which present the possibility of intentionally controlling floats' motion by dynamically commanding them to linger at different depths. This project explores the use of these current predictions to direct float networks to some desired final formation or position. It presents multiple algorithms for such path optimization and demonstrates their advantage over the standard approach of constant-depth drifting.

  20. Novel Strategy to Fabricate Floating Drug Delivery System Based on Sublimation Technique.

    PubMed

    Huanbutta, Kampanart; Limmatvapirat, Sontaya; Sungthongjeen, Srisagul; Sriamornsak, Pornsak

    2016-06-01

    The present study aims to develop floating drug delivery system by sublimation of ammonium carbonate (AMC). The core tablets contain a model drug, hydrochlorothiazide, and various levels (i.e., 0-50% w/w) of AMC. The tablets were then coated with different amounts of the polyacrylate polymers (i.e., Eudragit® RL100, Eudragit® RS100, and the mixture of Eudragit® RL100 and Eudragit® RS100 at 1:1 ratio). The coated tablets were kept at ambient temperature (25°C) or cured at 70°C for 12 h before further investigation. The floating and drug release behaviors of the tablets were performed in simulated gastric fluid USP without pepsin at 37°C. The results showed that high amount of AMC induced the floating of the tablets. The coated tablets containing 40 and 50% AMC floated longer than 8 h with a time-to-float of about 3 min. The sublimation of AMC from the core tablets decreased the density of system, causing floating of the tablets. The tablets coated with Eudragit® RL100 floated at a faster rate than those of Eudragit® RS100. Even the coating level of polymer did not influence the time-to-float and floating time of coated tablets containing the same amount of AMC, the drug release from the tablets coated with higher coating level of polymer showed slower drug release. The results suggested that the sublimation technique using AMC is promising for the development of floating drug delivery system. PMID:26314245