30,738 research outputs found
Unlimited simultaneous discrimination intervals in regression Technical report no. 90
Unlimited simultaneous discrimination intervals in linear regression
The Microstructure of the Hen\u27s Egg Shell - A Short Review
The structure of the hen\u27s egg shell can be divided into five separate layers . The Innermost layer consists of two distinct membranes known as the inner and outer shell membranes. These membranes are compos ed of networks of protein/polysaccharide fibres and are =70 mm thick. Attached to the outer fibres of the outer membrane are polycrystals of calcite (calcium carbonate) which extend outward in an inverse conical manner until the cones from several sites of crystal i nit iation fuse together. The fibre/ crystal attachment sites, known as basal caps, and the cones form the mammillary knobs layer which is :: 100- 110 llm thick. After the cones fuse with each other, continuing calcite deposition produces columnar crystals 10 -30 \u27m in diameter and :::200 llm in length. These crys tals form the palisade layer and are intermingled with a protein/polysaccharide matrix that differs in composition From the shell membranes. Over the columnar crystals is a thin layer (::S -8 \u27m thick), known as the vertical crystal layer, of small calcite crystals that are orientated perpendicular to the shell\u27s surface. The cuticle is the outermost layer of the shell; it is =10 mm thick and contains predominantly protein. Passing vertically through the palisade layer of the shell from valleys between the marrmillary knobs to the surface of the vertical crystal layer are funnel - shaped, unbranched pores, These pores are capped by the cuticle which is cracked and thus allows the diffusion of gases between the contents of the egg and its environment. The geometrical configuration of the cones in the mammillary knobs layer is related to the thickness of shell. Specific amino acids in the membrane fibres
The Microstructure of the Hen\u27s Egg Shell - A Short Review
The structure of the hen\u27s egg shell can be divided into five separate layers . The Innermost layer consists of two distinct membranes known as the inner and outer shell membranes. These membranes are compos ed of networks of protein/polysaccharide fibres and are =70 mm thick. Attached to the outer fibres of the outer membrane are polycrystals of calcite (calcium carbonate) which extend outward in an inverse conical manner until the cones from several sites of crystal i nit iation fuse together. The fibre/ crystal attachment sites, known as basal caps, and the cones form the mammillary knobs layer which is :: 100- 110 llm thick. After the cones fuse with each other, continuing calcite deposition produces columnar crystals 10 -30 \u27m in diameter and :::200 llm in length. These crys tals form the palisade layer and are intermingled with a protein/polysaccharide matrix that differs in composition From the shell membranes. Over the columnar crystals is a thin layer (::S -8 \u27m thick), known as the vertical crystal layer, of small calcite crystals that are orientated perpendicular to the shell\u27s surface. The cuticle is the outermost layer of the shell; it is =10 mm thick and contains predominantly protein. Passing vertically through the palisade layer of the shell from valleys between the marrmillary knobs to the surface of the vertical crystal layer are funnel - shaped, unbranched pores, These pores are capped by the cuticle which is cracked and thus allows the diffusion of gases between the contents of the egg and its environment. The geometrical configuration of the cones in the mammillary knobs layer is related to the thickness of shell. Specific amino acids in the membrane fibres
Sonobuoy Mils
The purpose of this paper is to describe a new technique for locating missile impact positions in the open ocean using Navy sonobuoys. Figure 1 shows a typical Navy ASW sonobuoy, an air-dropped, expendable VHF radio that relays the underwater acoustic signals received on a hydrophone beneath it to an aircraft overhead* This missile impact location system has the advantages of being low cost, portable and capable of high accuracy. Basically the sonobuoys monitor the hydroacoustic signal of a missile impact on the ocean\u27s surface and use fixed ocean bottom transponders as a geodetic reference for the sonobuoys* Heretofore we have used aircraft dropped sofar charges as an acoustic tie between the surface sonobuoys and the ocean bottom transponders. Impact accuracy in this sonobuoy system of 0.1 NM is possible. In the future, with a little more hardware development, the use of active sonobuoys will eliminate the need for the sofar charge reference tie and the upgraded SMILS will have an accuracy of 250\u27
The effect of low-energy ion-implantation on the electrical transport properties of Si-SiO2 MOSFETs
Using silicon MOSFETs with thin (5nm) thermally grown SiO2 gate dielectrics,
we characterize the density of electrically active traps at low-temperature
after 16keV phosphorus ion-implantation through the oxide. We find that, after
rapid thermal annealing at 1000oC for 5 seconds, each implanted P ion
contributes an additional 0.08 plus/minus 0.03 electrically active traps,
whilst no increase in the number of traps is seen for comparable silicon
implants. This result shows that the additional traps are ionized P donors, and
not damage due to the implantation process. We also find, using the room
temperature threshold voltage shift, that the electrical activation of donors
at an implant density of 2x10^12 cm^-2 is ~100%.Comment: 11 pages, 10 figure
Encapsulation of phosphorus dopants in silicon for the fabrication of a quantum computer
The incorporation of phosphorus in silicon is studied by analyzing phosphorus
delta-doped layers using a combination of scanning tunneling microscopy,
secondary ion mass spectrometry and Hall effect measurements. The samples are
prepared by phosphine saturation dosing of a Si(100) surface at room
temperature, a critical annealing step to incorporate phosphorus atoms, and
subsequent epitaxial silicon overgrowth. We observe minimal dopant segregation
(5 nm), complete electrical activation at a silicon growth temperature of 250
degrees C and a high two-dimensional electron mobility of 100 cm2/Vs at a
temperature of 4.2 K. These results, along with preliminary studies aimed at
further minimizing dopant diffusion, bode well for the fabrication of
atomically precise dopant arrays in silicon such as those found in recent
solid-state quantum computer architectures.Comment: 3 pages, 4 figure
The Generalized Ricci Flow for 3D Manifolds with One Killing Vector
We consider 3D flow equations inspired by the renormalization group (RG)
equations of string theory with a three dimensional target space. By modifying
the flow equations to include a U(1) gauge field, and adding carefully chosen
De Turck terms, we are able to extend recent 2D results of Bakas to the case of
a 3D Riemannian metric with one Killing vector. In particular, we show that the
RG flow with De Turck terms can be reduced to two equations: the continual Toda
flow solved by Bakas, plus its linearizaton. We find exact solutions which flow
to homogeneous but not always isotropic geometries
A compactness theorem for complete Ricci shrinkers
We prove precompactness in an orbifold Cheeger-Gromov sense of complete
gradient Ricci shrinkers with a lower bound on their entropy and a local
integral Riemann bound. We do not need any pointwise curvature assumptions,
volume or diameter bounds. In dimension four, under a technical assumption, we
can replace the local integral Riemann bound by an upper bound for the Euler
characteristic. The proof relies on a Gauss-Bonnet with cutoff argument.Comment: 28 pages, final version, to appear in GAF
The measurement of lubricant-film thickness using ultrasound
Ultrasound is reflected from a liquid layer between two solid bodies. This reflection depends on the ultrasonic frequency, the acoustic properties of the liquid and solid, and the layer thickness. If the wavelength is much greater than the liquid-layer thickness, then the response is governed by the stiffness of the layer. If the wavelength and layer thickness are similar, then the interaction of ultrasound with the layer is controlled by its resonant behaviour. This stiffness governed response and resonant response can be used to determine the thickness of the liquid layer, if the other parameters are known.
In this paper, ultrasound has been developed as a method to determine the thickness of lubricating films in bearing systems. An ultrasonic transducer is positioned on the outside of a bearing shell such that the wave is focused on the lubricant-film layer. The transducer is used to both emit and receive wide-band ultrasonic pulses. For a particular lubricant film, the reflected pulse is processed to give a reflection-coefficient spectrum. The lubricant-film thickness is then obtained from either the layer stiffness or the resonant frequency.
The method has been validated using fluid wedges at ambient pressure between flat and curved surfaces. Experiments on the elastohydrodynamic film formed between a sliding ball and a flat surface were performed. Film-thickness values in the range 50-500 nm were recorded, which agreed well with theoretical film-formation predictions. Similar measurements have been made on the oil film between the balls and outer raceway of a deep-groove ball bearing
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