A force sensor chip including a semiconductor substrate having a plurality of strain resistance elements and temperature-compensating resistance elements corresponding to the resistance elements is disclosed. The structure in the periphery of parts where the strain resistance elements, which are provided to deforming parts in the action part formed on the semiconductor substrate, are disposed is the same as the structure in the periphery of parts where the temperature-compensating resistance elements in the action part are disposed.

In machine tools and other automated machinery, the work operation involves a force being applied to an object that is to be worked, or a force being received from an external source. In such cases, automated machines require that the moment and external force applied thereto be detected, and a control corresponding to the force and moment be carried out. The external force and moment must be accurately detected in order to carry out the control corresponding to the force and moment with high accuracy.
In view of this, a variety of force sensors have been proposed in the past. Using the detection method as a basis, the force sensors are normally classified into elastic force sensors and balanced force sensors. The elastic force sensor measures force on the basis of the amount of deformation in proportion to the external force. The balanced force sensor measures force according to a balance with a known force.
The theoretical structure of another known force sensor involves a plurality of strain resistance elements being provided to a portion of a load cell, which elastically deforms in response to an external force. When an external force is applied to the load cell of the force sensor, electric signals according to the degree of deformation (stress) of the load cell are outputted from the plurality of stress resistance elements. The force of two or more components or the like applied to the load cell can be detected on the basis of these electric signals. The measurement of stress generated in the force sensor is calculated on the basis of the electric signals described above.
A six-axis force sensor is one known type of force sensor. The six-axis force sensor, which is a type of elastic force sensor, has a plurality of strain resistance elements provided to a load cell portion. The six-axis force sensor detects an external force as six axis components, which are divided into stress components (force: Fx, Fy, Fz) in the direction of the three axes (X axis, Y axis, and Z axis) of a Cartesian coordinate system; and torque components (moment: Mx, My, Mz) in the direction of the axes.
Japanese Patent Application Laid-Open Publication No. 2006-125873 (JP 2006-125873 A) discloses a multi-axis force sensor chip and a multi-axis force sensor assembled using this chip.
In the multi-axis sensor chip, a semiconductor manufacturing technique is used to form a plurality of strain resistance elements on a connecting part of a semiconductor substrate (base member) having a prescribed shape and structure. The strain resistance elements is affected by the stress generated in response to the force or moment applied to an operating part of the semiconductor substrate, and the resistance values change. The force or moment applied to the operating part of the semiconductor substrate is calculated by appropriately combining the resistance values of the plurality of strain resistance elements.
In the multi-axis sensor disclosed in JP 2006-125873 A, temperature-compensating resistance elements are provided correspondingly with respect to the plurality of strain resistance elements. The variation characteristics of the resistance values of the strain resistance elements are inherently temperature-dependent, and the corresponding temperature-compensating resistance elements and the stress resistance elements are therefore equally affected by temperature.
A thick film circuit board for a pointing stick is disclosed in Japanese Patent Application Laid-Open Publication No. 2000-267802 (JP 2000-267802 A). A pointing stick is a component used as a signal input device in a notebook computer or the like. A signal input operation is carried out by manipulating a pointing stick in the x, y, and z directions using finger pressure. When a finger manipulates the pillar-shaped body that constitutes the stick, a lower end part of the pillar-shaped body applies a force or moment to a center part (force action point) of the thick film circuit board. When the thick film circuit board deforms, the resistance values of the plurality of resistance bodies on the thick film circuit board are varied, and an input signal is generated. According to the thick film circuit board, four resistance elements are disposed in a point-symmetrical positional relationship around the force action point in order to provide a satisfactory output balance among the axes.
According to the multi-axis force sensor chip disclosed in JP 2006-125873 A, the temperature-compensating resistance elements are provided to locations such that the distance to the locations where the strain resistance elements are disposed (which are regions where the semiconductor substrate does not deform) can be reduced to the greatest extent possible; and such that the temperature conditions can be made equal. This is performed in order to remove the effect of the temperature on the temperature-dependent strain resistance elements. It is thereby possible to compensate for the temperature with high accuracy.
However, even when the temperature-compensating resistance elements are provided to locations where the temperature conditions are the same as those where the strain resistance elements are disposed (non-deforming regions), the initial resistance values (resistance values when no load is present) of the strain resistance elements will actually be irregular. As a result, a problem occurs in that optimal values will not necessarily be obtained even when the temperature-compensating resistance elements are used to perform temperature compensation on the output values of the strain resistance elements.
In the multi-axis force sensor chip, it is desirable for the outputs across the axes to be properly balanced, and a proposal for achieving such a result is disclosed in, e.g., JP 2000-267802 A. However, the structure of the thick film circuit board disclosed in JP 2000-267802 A corresponds to a ceramic substrate. In the case of a semiconductor substrate, the crystal orientation in the semiconductor substrate must be taken into consideration in order to equalize the output resistance values across the axes.
Furthermore, as mentioned in JP 2006-125873 A as well, the temperature-compensating resistance elements are disposed with consideration given to crystal orientation so that the strain sensitivity of the strain resistance elements is considerably higher than the strain sensitivity of the temperature-compensating resistance elements. However, this document does not disclose the concept of determining the layout of the resistance elements in consideration of the crystal orientation from the standpoint of properly balancing the outputs across the axes.


The present invention provides an improved method for reducing the risk or severity of restenosis following cardiac angioplasty. The method includes administering to a target vessel region, a morpholino antisense compound having uncharged phosphorus-containing backbone linkages, and spanning the start codon of a human c-myc mRNA. Also disclosed are novel antisense compounds and compositions, and a method for assaying the effectiveness of antisense delivery and uptake to a target vessel region.

Transluminal coronary angioplasty was introduced in the late 1970's as a nonsurgical treatment for obstructive coronary artery disease. Since its introduction, major advances in equipment and techniques have led to widespread use of the method for treating coronary artery disease and angina. Typically, the procedure involves placing a balloon-tip catheter at the site of occlusion, and disrupting and expanding the occluded vessel by inflating the catheter balloon.
Despite improvements in equipment and techniques, restenosis persists as the limiting factor in the maintenance of vessel patency in angioplasty, occurring in 30% to 50% of patients, and accounting for significant morbidity and health care expenditures. (Casterella). Post-angioplasty restenosis is a segmentally limited, wound healing response to a traumatization of the vascular wall. Studies with animal models and human autopsy plaque tissue indicate a cascade-like course of events triggered by (a) destruction of endothelial and subendothelial structures, (b) traumatization of medial regions with rupture of the internal elastic lamina, (c) release of thrombogenic factors such as collagen or tissue factor, (d) stretching of smooth muscle cells with subsequent expression of proto-oncogenes (c-fos, c-myc, c-myb), (e) release of growth factors from cells of the bloodstream, endothelial cells and SMCs, and (f) thrombin production with autocatalytic activation of the SMC thrombin receptor (Bauriedel).
Overlapping the inflammation period, granulation begins 3 days after angioplasty. Proteinases such as plasmin as well as collagenases induce the disintegration of extracellular matrix structures, thereby modulating plaque formation, and lead to an organelle-rich SMC phenotype within the intima and media. Overlapping with the granulation period, induction of different components of the extracellular matrix occurs 1–2 weeks after angioplasty, possibly mediated by TGF-beta (phase of matrix formation). Smooth muscle cells produce and secrete matrix proteins such as tenascin, fibronectin, collagens and proteoglycans, and thereby induce a marked increase of the neointimal plaque volume. (Bauriedel).
Clinical trials in restenosis prevention using various revascularization devices, antiplatelet drugs, antithrombotic drugs, and anti-inflammatory agents have produced limited improvement in the incidence of restenosis. Also reported are attempts to improve the risk or severity of restenosis with intravascular stents (Savage, Eisenhower, Rubarteli, Gottman), radiation therapy (Koh), and administration of anti-proliferative drugs at the vessel injury site. The latter approach typically employs the balloon catheter for introducing the therapeutic agent at the vessel occlusion site (Dick, Roy, Dev, Kimura, Alfke, Robinson 1997a, Robinson 1997b, Barath, Herdeg, Pavlides, Oberhoff, Hodgkin, Hong, Consigny, Meyer, Fernadez-Ortiz, Lambert, and Wilensky), or releasing drug from a stent (Teomin, Bartonelli, Raman, Gibson).
Despite these advances, the incidence of restenosis, and the inability to predict the response to treatment, remains a serious risk factor in vascular angioplasty. It would therefore be desirable to (i) provide a treatment method which shows efficacy in reducing the incidence and severity of restenosis following vascular angioplasty, (ii) is well tolerated by the patients, with few or any side effects, and (iii) can be carried out with a variety of therapeutic delivery methods.
It would also be desirable to provide improved therapeutic compounds and compositions for carrying out the method, and a simple, rapid clinical assay for monitoring effectiveness of the delivery of a therapeutic compound to the vessel target site.

Antisense restenosis composition and method


A semiconductor laser diode comprising a semiconductor substrate having an active layer with a pair of cavity facets opposed to each other on both ends of active layer as well as a first dielectric film of an oxide and a second dielectric film of an oxynitride successively stacked on one cavity facet has sufficient initial characteristics with a film structure having excellent heat radiability for allowing stable high-output lasing over a long period without reducing a catastrophic optical damage level on an emission end.

1. Field of the Invention
The present invention relates to an end emission type semiconductor laser diode, and more specifically, it relates to a semiconductor laser diode stably operating with a high output over a long time while suppressing aged deterioration of an emission end resulting from reduction of a catastrophic optical damage level.
2. Description of the Background Art
When the quantity of current injection is increased in an end emission type semiconductor laser diode of the 650 nm band or the 780 nm band in order to increase the light output, the light output is abruptly reduced to stop lasing. This phenomenon, resulting from catastrophic optical damage (hereinafter abbreviated as COD) to an emission end of the semiconductor laser diode, is conceivably caused through the following mechanism: When current is injected into the semiconductor laser diode, non-radiative recombination current flows through high-density surface levels present on the emission end due to the presence of an oxide or the like. Therefore, the carrier concentration is reduced on the emission end as compared with that in the semiconductor laser diode, leading to light absorption. The semiconductor laser diode generates heat by this light absorption to increase the temperature on the emission end, whereby the bandgap energy on the emission end is reduced to further increase light absorption. This positive feedback loop so extremely increases the temperature of the emission end that the emission end is finally melted to stop lasing.
The COD level of a recent high-output semiconductor laser diode can be increased by disordering an emission end through a window structure for increasing bandgap energy of the disordered emission end and reducing the level of light absorption resulting from surface levels. When the semiconductor laser diode having such a window structure is oscillated over a long period, however, the COD level is disadvantageously reduced due to aged deterioration.
In order to obtain a high COD level, therefore, the temperature of the emission end must be reduced by improving heat radiability of the semiconductor laser diode. In this point of view, various proposals have been made in general.
For example, Japanese Patent Laying-Open No. 03-209895 (1991) (Patent Literature 1) describes that a function of an excellent end protective film can be ensured in a semiconductor laser diode of the 780 nm band having an AlxOyNz film (x+y+z=1) formed as a first dielectric film with an AlGaAs active layer by forming a single AlxOyNz layer having a thermal expansion coefficient close to that of AlGaAs forming the active layer while ensuring heat radiability.
Japanese Patent Laying-Open No. 2003-264333 (Patent Literature 2) discloses a technique of solving such a problem that particles easily adhere to an SiN film exposed on a surface to deteriorate chemical resistance by stacking a first dielectric film of Al2O3, a second dielectric film of Si3N4 or AlN and a third dielectric film of Al2O3 with each other thereby covering the surfaces of the Si3N4 or AlN film with the Al2O3 films on the basis of the idea disclosed in Japanese Patent Laying-Open No. 09-326527 (1997) (Patent Literature 3).


A depth sensing system includes a sensor having first and second sensor pixels to receive light from a surface. The system also includes a filter to allow transmission of full spectrum light to the first sensor pixel and visible light to the second sensor pixel while preventing transmission of infrared light to the second sensor pixel. The system further includes a processor to analyze the full spectrum light and the visible light to determine a depth of the surface. The filter is disposed between the sensor and the surface.

Depth sensing is the determination of the distance between a known point in three dimensional ("3D") space (e.g., a sensor) and a point of interest ("POI") on a surface of an object. Depth sensing is also known as texture sensing because determining the respective distances of a plurality of POIs on a surface determines the texture of that surface. Depth or texture sensing is useful for many computer vision systems, including mixed reality systems.
Modern computing and display technologies have facilitated the development of mixed reality systems for so called "virtual reality" or "augmented reality" experiences, wherein digitally reproduced images or portions thereof are presented to a user in a manner wherein they seem to be, or may be perceived as, real. A virtual reality, or "VR", scenario typically involves presentation of digital or virtual image information without transparency to actual real-world visual input. An augmented reality, or "AR", scenario typically involves presentation of digital or virtual image information as an augmentation to visualization of the actual world around the user (i.e., transparency to other actual real-world visual input). Accordingly, AR scenarios involve presentation of digital or virtual image information with transparency to other actual real-world visual input.
Various optical systems generate images at various depths for displaying mixed reality (VR and AR) scenarios. Some such optical systems are described in U.S. Utility patent application Ser. No. 14/738,877, the contents of which have been previously incorporated-by-reference herein. Other such optical systems for displaying mixed reality scenarios are described in U.S. Utility patent application Ser. No. 14/555,585 filed on Nov. 27, 2014, the contents of which are hereby expressly and fully incorporated by reference in their entirety, as though set forth in full.
AR scenarios often include presentation of virtual image elements in relationship to real-world objects. For example, referring to FIG. 1, an augmented reality scene 100 is depicted wherein a user of an AR technology sees a real-world park-like setting 102 featuring people, trees, buildings in the background, and a concrete platform 104. In addition to these items, the user of the AR technology also perceives that he "sees" a robot statue 106 standing upon the real-world platform 104, and a cartoon-like avatar character 108 flying by which seems to be a personification of a bumble bee, even though these elements 106, 108 do not exist in the real world. In order to present a believable or passable AR scene 100, the depth of real world objects (e.g., the platform 104) must be determined to present virtual objects (e.g., the robot statue 106) in relation to real world objects.
VR scenarios that include reproduction of portions of real world environments can also benefit from determination of the depth and texture of those portions of the real world environment. Accurate depth and texture information will result in more accurate VR scenarios. Both AR and VR scenarios may also include outwardly directed cameras to capture portions of real world environments (e.g., for analysis or transmission). Focusing these outwardly directed cameras can be aided by determination of the depth of those portions of the real world environment.
One approach to depth sensing includes measuring the respective angles between the optical axes of two images (which are separated by a known distance at a known orientation) of a single POI on a surface and the POI on the respective images. Then determining the depth of the surface by triangulating the measured angles and the known distance between the image capture locations. Problems with this approach include (1) identification of the POI (especially on a homogenous surface) ("identification problem") in the first image and (2) identification of the corresponding POI in the second image ('correspondence problem"). The systems and methods described herein are configured to address these challenges.


A computer-implemented method and device for determining a user position, implemented in a user handheld computing device programmed to perform the method. The method includes solving for the position of a user based on ranges, which are computed by estimating power loss between a user and a number of Wi-Fi Access Points. Embodiments of the present invention includes a method that is designed to accommodate the non-linear nature of solving a position solution using power estimates. This method includes solving a two-dimensional solution grid of position residuals, or magnitudes of error between true and computed ranges, using signal strength measurements from multiple Wi-Fi access points in order to determine local minima of the position residuals indicating a user position. Standard approaches in the area such as a Least Squares Solution overly simplify the non-linear components resulting in poor performance.

The present invention relates to portable device navigation/positioning methods and devices. More specifically, embodiments of the present invention relate to methods and devices using data from Wi-Fi Access points for navigation/positioning purposes.
The use of navigational tools within portable handheld devices has been widespread in contemporary society. The ability to quickly and accurately determine a user's location and heading toward a desired destination is highly desirable. Conventional tools for navigation have included systems that implement GPS or other Radio-Frequency based positioning methods. However, these methods require frequent updating to remain accurate. As GPS and other Radio-Frequency based positioning become either degraded or completely unavailable, systems that utilize these methods are rendered useless.
From the above, it is seen that techniques for improving operation of navigational systems and methods are highly desired.

Methods and devices for position determination using regional minimal residual estimation


A novel spin resonance microscope is disclosed, the microscope design comprising an integrated evanescent wave probe and scanning tunneling microscope tip. The probe and tip may be either the same structure, or they may be separate structures. The integrated design allows for coherent excitation of precessing electron spin states in the sample such that spin resonance may be detected because the tunneling current is modulated by the spin resonance. Spin resonance may be affected by either adjacent nuclei, or by adjacent electrons. The present apparatus requires significantly reduced power inputs, such that the dead time of the system is short, and relaxation phenomena may be evaluated without swamping the instrument's electronics.

1. Field of the Invention
Embodiments of the present invention are directed in general to the field of high-resolution, high-sensitivity nuclear and/or electron spin resonance detection. More specifically, the present invention is directed to evanescent wave probe (EWP) techniques used in conjunction with scanning tunneling microscopy (STM) to detect nuclear and/or electron spin resonance.
2. State of the Art
In the discussion of the state of the art that follows, reference is made to certain structures and/or methods. However, the following references should not be construed as an admission that these structures and/or methods constitute prior art. Applicants expressly reserve the right to demonstrate that such structures and/or methods do not qualify as prior art against the present invention.
Spectroscopy and imaging technologies based on magnetic resonance, e.g., electron spin resonance (ESR), also known as electron paramagnetic resonance (EPR), and nuclear magnetic resonance (NMR) have in the past played critical roles in characterizing fundamental properties of molecular structure and materials as well as playing critical roles in medical diagnosis. Dramatic advances in nano-technology, quantum computing, proteomics, combinatorial screening of catalysts and the monitoring of other chemical reactions involving free radicals, and biomedical sciences such as drug screening, have increased the sensitivity requirements for nanoscale spatially resolved magnetic resonance spectroscopy and imaging technologies.
Spin label EPR and NMR spectroscopy is a very powerful tool for determining three dimensional (3-D) protein structures/functionality and protein-ligand interaction in drug-screening. Relative to X-ray structural determination, EPR and NMR do not require protein crystal growth, which requirement is a major disadvantage of the x-ray technique, and thus one may study proteins under physiological conditions using EPR and/or NMR. Electron paramagnetic resonance (EPR) spectroscopy of a site-directed spin label (SDSL) on proteins can reveal protein motion and determine protein structure of any size. Compared to fluorescence spectroscopy techniques, in which fluorescent tags are attached to proteins, spin labels are much smaller and less likely to interfere with the protein's native structure and movement. Spin label-EPR techniques are more sensitive and require less protein than NMR, but current instrumentation is much less sensitive than fluorescence spectroscopy. In addition, commercial instrumentation currently available lags behind NMR by about 20 years in that a time resolved pulse measurement capability is not available (due to some fundamental difficulties in instrumentation development). This has slowed and hampered the adaptation of the new SDSL technology in bio-technology.
A typical magnetic resonance (NMR or ESR) system applies radiation in either the RF or microwave region of the electromagnetic spectrum to a sample already subjected to an external magnetic field, wherein the applied radiation may be either continuous or pulsed, and the radiation having a frequency that is tuned to the specific nuclear or electron spin resonance under consideration. The protons (in the case of NMR) or the electrons (in the case of ESR) absorb the energy and precess coherently at a particular frequency in a particular direction. The resonance frequency v of a spin is proportional to the external magnetic field B, and the energy of absorption hv=gμB, where h is Planck's constant, g is Landé g factor, and μ is either the nuclear magneton μN for the NMR case, or the Bohr magneton μB for the case of ESR.
In a typical nuclear spin resonance experiment, electronic shielding of nuclear spins will induce a very small so-called "chemical shift" to the nuclear spin resonance. It is possible to measure this small shift when the sample has been placed in a highly uniform magnetic field B0, since the nuclear spin resonance line width is extremely narrow. One of the most powerful features and capabilities of conventional NMR is the structural determination that is possible through precise measurement of the chemical shift. Any non-uniformity in the static magnetic field will tend to smear out the small chemical shift and render a NMR instrument useless for structure determination. In this situation, NMR machines have only the capability of structural determination with large volumes of homogenous specimens, and cannot provide significant spatial resolution.
In contrast, magnetic resonance imaging (MRI) does have the capability of imaging with a certain spatial resolution, which is usually in the mm range. This capability is realized through a high magnetic field gradient generated in the specimen such that the spatial resolution is proportional to the degree of the gradient. Three-dimensional MRI imaging is achieved typically by applying a linear magnetic field gradient during the period that the RF pulse is applied. The field gradient determines a sensitive slice in which the resonance condition, a local function of the applied field, is met. This gradient magnetic field is turned on and off very rapidly, altering the main magnetic field on a very local level. When the RF pulse is turned off, the precessing hydrogen protons slowly decay back to their thermal equilibrium states. An induced transient induction signal in a magnetic resonance experiment is detected using a pickup coil, and the signal is sent to a computer system for processing.
In the magnetic resonance imaging technique the presence of a field gradient smears out chemical shifts and the different resonance peaks (similar nuclear spin resonances having different chemical shifts) become one broad peak. The MRI resonance peak is at least 100 times broader than normal NMR peak. Consequently, conventional MRI imaging techniques lacks the capability of spectroscopy and structural determination. Furthermore, chemical shifts in nuclear spin resonance also limit the spatial resolution of MRI, since a 10 ppm typical chemical shift determines the MRI spatial resolution to an order of millimeters.
In the past, magnetic resonance experiments have been conducted in conjunction with scanning tunneling microscopy (STM), the latter being a revolutionary technique that is capable of atomic resolution. In recent years, ESR-STM has been reported to be able to detect the local precessing of spins on the surface of a semiconducting or conducting material, enabled by observing the microwave modulation of the tunneling current induced by precessing spins when an external magnetic field is applied. This phenomenon has been interpreted as a consequence of the spin-orbital coupling at a single atomic site, where the electron populates a mixed state of two electron spin states (Zeeman levels) split by the applied magnetic field. However, current magnetic resonance-STM experiments rely on the production of spin precessing by random thermal fluctuations. Furthermore, the reported data from these experiments has not been widely reproduced and accepted due to limited sensitivity, and difficulties in impedance matching between the RF portions of the experimental configuration (typically 50 ohms) and the high impedance tunneling current circuits.
What is needed is a method of inducing spin precession and excitation between spin states that does not rely on random thermal fluctuations, such that nuclear and/or spin resonance techniques may be carried out with increased resolution and sensitivity.

Integrated EWP-STM spin resonance microscope


The embodiments described herein include a host that includes an operating system and a storage simulation module in communication with the host. The storage simulation module includes a pseudo-adapter configured to emulate a storage adapter and a pseudo-storage device coupled to the pseudo-adapter, wherein the pseudo-storage device is configured to emulate a storage device. The storage simulation module is configured to simulate an error event for the pseudo-adapter and/or the pseudo-storage device upon receipt of an operation from the operating system.

Many systems use a server-based computing model, such as a virtual desktop infrastructure (VDI) to provide complete, centrally-managed desktops to users using computer virtualization technology. The VDI is used to create large numbers of independent computing environments for large numbers of users. In a typical VDI architecture, user displays and input devices are local, but applications execute remotely in a server. As such, a virtual desktop may be accessible by one or more remote users through a network. The virtual desktop may mimic a desktop computer interface or an interface of another computer or system by providing a virtual screen or virtual display to an end user. A protocol, such as an application programming interface (API), may be used to integrate VDI software components with other products. For example, a VDI operating system component may implement an API to provide an interface with third-party vendor applications such as a custom multi-pathing plugin or device driver for a storage vendor's storage devices.
To ensure that they work adequately and meet a predefined threshold level for quality, APIs need to be tested. Some commonly known testing techniques can be used to test APIs. For example, unit testing, a method used to test individual units of source code, can be used to call APIs with various inputs and validate the resulting outputs. Functional or system testing, which invokes APIs indirectly by running workloads from user space, can also be used to test APIs. Function testing has the advantage of more closely resembling the manner in which users actually use the system.
However, there are limitations to existing testing techniques. For example, various categories of APIs, such as those that may generate failure responses based on the status of other system components, may be difficult to verify with unit tests because unit tests are, by definition, limited to testing individual units of source code. Even if unit tests could handle these types of APIs, a variety of real storage devices may be difficult to procure for testing environments, and staging specific error events or conditions within each of those proprietary storage devices may be difficult or impossible. Functional or system testing approaches are also limited because it may be difficult, if not impossible, for them to call and examine the response to lower-level, kernel APIs by running user space workloads. Finally, error handling code is often tested poorly, as error conditions are difficult to generate deterministically.

This patent is subject to a terminal disclaimer.


A method for photoelectrochemical (PEC) etching of a p-type semiconductor layer simply and efficiently, by providing a driving force for holes to move towards a surface of a p-type cap layer to be etched, wherein the p-type cap layer is on a heterostructure and the heterostructure provides the driving force from an internal bias generated internally in the heterostructure; generating electron-hole pairs in a separate area of the heterostructure than the surface to be etched; and using an etchant solution to etch the surface of the p-type layer.

1. Field of the Invention
This invention relates to roughening of p-type GaN layers and a photoelectrochemical method for etching and roughening p-type GaN layers.
2. Description of the Related Art
(Note: This application references a number of different publications as indicated throughout the specification by one or more reference numbers within brackets, e.g., [x]. A list of these different publications ordered according to these reference numbers can be found below in the section entitled "References." Each of these publications is incorporated by reference herein.)
Photoelectrochemical (PEC) wet etching has been applied to a variety of semiconductors, including GaAs, InP, and GaN. For GaN especially, PEC etching has been of great interest since there are very limited alternatives for room temperature wet etching.
FIG. 1 illustrates a PEC etching setup according to the present invention which includes a light source (e.g., above-bandgap 1000 Watt Xe lamp 100) and an electrochemical cell, where the semiconductor (of the e.g., GaN Light Emitting Diode (LED) sample 102) acts as the anode of the system and has metal 104 (usually platinum) patterned directly on it to act as the cathode. Light 106 generates electron-hole pairs in the semiconductor, and electrons are extracted through the cathode, while holes participate in oxidation reactions at the semiconductor surface, causing the semiconductor surface to be dissolved in an electrolyte 108. Because of the surface band bending at the semiconductor/electrolyte interface, holes are typically confined at the surface in n-type materials only, while electrons are confined at the surface in p-type materials. In addition, accumulation of photogenerated electrons at the p-type semiconductor surface constrains the etching of that material. Thus, PEC etching of p-type semiconductors has been difficult to achieve. The light 106 from the light source 100 may be filtered, for example, by a GaN filter 110, the metal 104 may be an opaque metal (e.g., Ti and Pt) mask, acting as the cathode, and the electrolyte solution 108 may be a 5 molar (M) potassium hydroxide (KOH) solution, for example. The p-GaN of the LED 102 is the anode for the PEC etching and the electrolyte 108 is in a container 112.
PEC etching is a well-established process used for n-type and unintentionally doped semiconductors, but it has had very limited success for etching p-type layers. There have been limited reports of PEC etching of p-type semiconductors in the past, but they have generally required elevated temperatures, a substantial external bias on the system, or a complex experimental apparatus. In addition, etch rates are generally very slow compared to n-type materials.
Several groups have used the application of a substantial external bias to p-type samples to achieve PEC etching of p-type semiconductors [1], [2]. Either a very large bias is necessary or the etch rate is very slow. Both of these groups used GaN. In the case of Borton et al. [1], a high-temperature KOH soak was necessary before etching, and then etching occurred under a small (˜2V) bias, resulting in etch rates on the order of 1-5 nm/minute and very rough morphology. Yang et al. [2] achieved higher etch rates (2 μm/minute) but had to apply an external bias of 10 V. Hwang et al. [3] used a chopped ultraviolet (UV) light source to achieve electrode-less etching of p-type GaN. They were able to obtain an etch rate of 2.8 nm/minute using this technique, but at the cost of increased roughness compared to similar etch conditions for n-type GaN.
Several groups have reported on the use of KOH/ethylene glycol mixtures to etch p-GaN in a purely chemical manner. However, this etch is very crystallographically selective, and also requires the use of quite elevated temperatures. The etch described in Na [5] requires a temperature of 165° C.
Deep UV irradation has been used for PEC etching of p-type GaAs [6]. This technique relies on the fact that the penetration depth of deep UV is very short in GaAs, and thus very high energy holes are generated close to the surface, are injected into the interface between the semiconductor and the electrolyte, and can participate in etching reactions there.
A two-compartment electrochemical cell has been used to PEC etch bulk p-GaAs [7]. In this case, the use of a basic solution on one side of the wafer and an acid solution on the other side of the wafer provides a driving force for holes to move towards the basic side. Light is incident on the acidic side so that electrons are confined there, while photogenerated holes diffuse to the basic side, driven by the difference in surface bandbending on the two sides, and participate in etching on the basic side in the absence of electrons. While feasible for fundamental studies of etching, this two-compartment geometry does not easily accommodate the practical etching of GaN devices.
Thus, there is a need in the art for improved processes for PEC etching p-type semiconductors. The present invention satisfies this need.

Photoelectrochemical etching of P-type semiconductor heterostructures

The Regents of the University of California


A new class of composite zeolite membranes and synthesis techniques therefor has been invented. These membranes are essentially defect-free, and exhibit large levels of transmembrane flux and of chemical and isotopic selectivity.

The present invention relates generally to membranes containing molecular sieves, and to new techniques for fabrication thereof.
Molecular sieves are nanoporous solids which possess small (typically  less than 10 xc3x85) pores which are intrinsic to their molecular structure. These pores can be used to selectively control rates of diffusion of various chemicals through a molecular sieve. Selectivity can be induced and controlled through the size and shape of the pore (i.e., simple xe2x80x9ckey-in-lockxe2x80x9d steric hindrance effects), and/or by including moieties which interact with the chemicals involved in manners which add to the selectivity of the pore. Such materials are used routinely in bulk form for separation of different gases, and for dehydration of a working atmosphere. They also have potential large-scale commercial applications in, e.g., high-temperature separation and selection of intermediate reaction products.
A particularly important subclass of molecular sieves are the zeolites. Zeolites are nanoporous inorganic alumino-silicates with pore diameters typically in the 3-7 xc3x85 range.
The crystalline nature of zeolites means that the pores are well defined in size, without variationxe2x80x94an intrinsic property of the crystal structure. That is, if a crystallographically oriented layer of zeolite crystals is grown, the pores thereof will share a common orientation relative to the growth surface. An orientation of particular interest is one in which the pores provide direct (if not exactly normal) paths through such a layer.
Zeolites are archetypal molecular sieves, partially because they are available with a wide range of pore diameters, and partially because they can be found naturally as a component of certain clays. Statements and claims made concerning zeolites generally apply to a broader range of molecular sieves.
However, the use of bulk zeolites is neither efficient nor effective for most chemical separation procedures. As the material is bulk, separation occurs because the difference in diffusion rates through the nanopores of the zeolite causes a large amount of one of the chemicals being separated to become temporarily trapped in the zeolite pores. This restricts one to use of batch or semi-batch separation processes, which are generally not compatible with a properly functioning continuous flow synthesis process, as is usually desirable for very large scale synthesis.
An example of the areas in which such membranes are potentially useful, if the fabrication limitations can be overcome, lies in the area of large-scale organic synthesis. A common situation is where an intermediate step in the synthetic process produces a variety of isomers, only one of which can be used as feedstock for the next step in the synthesis. This situation is often met by taking the typically high-temperature (perhaps 300-500 C.) intermediate product mixture, cooling it to liquid nitrogen temperatures, and then separating the isomers using fractional distillation, a slow and expensive technique. The desired isomer is then heated back to the processing temperature, and the synthetic process proceeds.
The cost of this separation step in energy alone is several tens of millions of dollars per year for a single plant, and the need for the additional apparatus to support the cooling, distillation, and reheating steps can represent a significant portion of the capital cost of the synthesis plant. Clearly there is a need for a substitute process with increased energy efficiency and lower capital cost. Thin film zeolite membranes could fill this role, if suitably defect-free and robust membranes could be fabricated.
One approach toward relieving the processing constraints involved with use of bulk zeolites for separation is to somehow make membranes which comprise zeolites, in which the zeolites can still function effectively as separators (i.e., active zeolites). Although it is in principle possible to create nanoporous materials from source materials which are not naturally porous (e.g., porous silicon, or acid-etched alloy sheets), present fabrication techniques therefor usually do not provide product with adequate selectivity for most practical applications.
Traditional approaches toward synthesis of thin film membranes comprising zeolites generally fall into three main classes. Self-supporting membranes can be made, essentially using sintering techniques. However, such membranes are not durable, and are difficult to adhere to a supportive substrate. Alternately, it is possible to grow single crystal zeolite films on suitable substrates. Unfortunately, such films are highly defective when made in sizes suitable for industrial applications.
The most intensively pursued approach toward fabricating thin film membranes which comprise active zeolites is to grow defective zeolite films (usually polycrystalline in structure), and attempt to fill in the defects using secondary growth of zeolites atop the original layer, or by depositing carbonaceous material in the defects. The result to date has been thick films with blocked flow channels leading to poor penetration flow rates, which have limited thermal stability and problems in adhering to suitable substrates.
Specific attempts to make satisfactory zeolite membranes deserve some description, as such point out the intractable practical problems which have appeared in past work. The publications discussed below are included in the Information Disclosure Statement for the instant application.
The zeolite most studied in the quest for robust selective membranes is ZSM5, which is an orthorhombic crystal type. The chemical formula is Nan[AlnSi96xe2x88x92nO192] with about 16 H2O of hydration, and n less than 27. The pores are aligned along the [010] and [100] crystallographic directions, and have sizes just over 5 xc3x85. The equivalent material with n=0 is sometimes called silicalite.
Chiou et al. (Journal of Materials Science Letters 15, 952-954 (1996)) describe a technique to fabricate continuous zeolite films and membranes. Continuous ZSM-5 films were hydrothermally grown on anodic alumina substrates. The hydrothermal crystal growth process is commonly used in this area of endeavor. The technique used by Chiou et al. is a typical one, although the results of such growth can depend strongly on the growth parameters chosen.
Chiou et al. carry out hydrothermal growth of ZSM-5 by forming a growth solution of tetraethylorthosilicate (TEOS), sodium hydroxide, tetrapropylammonium bromide (TPABr), and de-ionized water so as to obtain the molar ratios 5Na2O :10TPABr:100SiO2:10000H2O. This growth solution and an anodic alumina substrate were sealed in a teflon-coated stainless-steel autoclave. Film growth was then induced by heating the autoclave to 180-200 C. for 1-4 days under autogenous pressure without stirring. The samples were then cooled, washed, and dried.
The result found by Chiou et al. was growth of a thick (about 30 microns) and nominally continuous layer of randomly oriented ZSM-5 crystallites. The lack of crystallite orientation and the extreme thickness makes such a layer inappropriate for use in chemical separation. The arrangement of crystallites makes it likely that large numbers of large pores, cracks, and other interstitial defects exist in these filmsxe2x80x94again destroying any potential for significant chemical selectivity in these materials.
C. Bai et al. (Journal of Materials Science 105, 79-87 (1995)) reported growth of chemically selective silicalite membranes on xcex3-alumina substrates. The layers, with thicknesses of about 5 microns, were grown from a gel on the surface of a tube.
The gel used in the growth process was prepared as follows. 0.95 grams of NaOH, 2.1 grams of TPABr, and 10 grams of finely divided silica were dissolved in 125 grams of distilled water. This solution was then mixed thoroughly and allowed to age for a day before being transferred to and sealed within a xcex3-alumina tube. The tube was placed in an autoclave, and heated to 180 C. under autogenous pressure for 12 hours. Repeated film growth steps were required to produce a nonpermeable membranexe2x80x94that is, one in which permeability appears only because of the pores, and not because of micro and macro defects.
As grown, the membrane pores were blocked by TPABr molecules. To remove these, the membrane was calcined in air. A very slow temperature ramp (about 0.1 C./minute) up to a temperature over 450 C. was required so that the calcining process did not crack the membrane. Significant, although not dramatic, levels of both physical and chemical selectivity were displayed by these membranes. However, the requirement for multiple growth steps, and the observed tendency to crack easily on changes in temperature, suggest that these membranes are unlikely to withstand the rigours of a commercial synthesis plant.
Lovallo and Tsapatsis (American Institute of Chemical Engineering Journal 42, 3020-3028 (1996)) report on their fabrication of a preferentially oriented submicron silicalite membrane. They deposited a precursor layer of zeolite nanocrystals, then used these nanocrystals as growth nuclei in more conventional hydrothermal growth.
A solution of silicalite nanocrystallites (about 1000 xc3x85 in size) were made by aging a standard growth solution as described above. Precursor films are then grown from a mixture of the above solution and a solution of alumina nanocrystallites. The resulting films were dried at 110 C., and calcined at between 550 C. and 750 C. for several hours. The resulting precursor films are polycrystalline and randomly oriented.
Secondary growth of the crystallites in this precursor film in a conventional hydrothermal growth environment results, under the published conditions, in preferential growth of platelike crystallites which grow together to form a continuous and intergrown layer. The crystallites making up this final layer are preferentially oriented. Unfortunately, both types are oriented parallel to the membrane surface, rather than the desired perpendicular orientation.
The above described efforts toward fabricating a zeolite membrane have concentrated on producing a continuous zeolite membrane by multiple zeolite growth cycles. Either hydrothermal growth or a combination of hydrothermal and sol-gel growth processes were used, but the material being grown has always been the desired zeolite.
Y. Yan et al. (Journal of Membrane Science 123, 95-103 (1997)) have investigated the possibility of xe2x80x9ccaulkingxe2x80x9d cracks and other micro defects in a polycrystalline zeolite layer with carbonaceous deposits. They refer to this procedure as xe2x80x9ccokingxe2x80x9d. A ZSM-5 membrane is grown much as described earlier, with an additional step of applying a diffusion barrier to the substrate surface so that the hydrothermal growth solution cannot penetrate into the substrate, thereby preventing formation of a layer which is too thick. Following growth, a large aromatic hydrocarbon is applied to the membrane. This hydrocarbon is too large to enter the ZSM-5 pores, but small enough that all microdefects in the membrane layer should be filled. At this point, the hydrocarbon is carbonized by exposing the membrane to temperatures of about 500 C. It does appear that this procedure is successful at closing many microdefects. However, there is also a large decrease of permeability through the zeolite pores, suggesting that this approach also closes such pores, despite the inability of the hydrocarbon to penetrate said pores. When this difficulty is combined with the probable lack of thermal cycling stability induced by differential thermal expansion between the coke and the zeolite membrane, it appears unlikely that this approach will routinely result in commercially useful membranes.
The present invention enables fabrication of suitable thin-film zeolite membranes by a combination of growth of zeolite crystallizes on a substrate followed by embedding said crystallites in a densified sol-gel product layer. The result is a robust, thermally stable, and highly selective membrane suitable for many chemical synthetic process steps.
The invention is of a new class of composite zeolite membranes and techniques for their fabrication. These membranes have a layer of zeolite crystallites on top of a porous substrate. The cracks and voids between the zeolite crystallites, which essentially eliminate the chemical selectivity which can be exhibited by zeolite nanopores, are filled in by a densified sol-gel product deposited by a sol-gel technique. The result is a rugged, highly selective membrane with good throughput.


A transmission device capable of changing speed with stored energy drives a carriage to move back and forth. The transmission device includes a variable speed transmission mechanism mounted on a base and driven by a motor. A first energy storage mechanism mounted on the variable speed transmission mechanism cooperates with a first latch mechanism mounted on the base so as to store and release the energy of the driven carriage, switch the output of the variable speed transmission mechanism, and thus switch the moving speed of the carriage.

1. Field of the Invention
The invention relates to a variable speed transmission device, and more particularly to a transmission device capable of changing speed with stored energy.
2. Description of the Related Art
Conventional speed-changing devices usually shift a relative position between some gears in a gear set with the extra manpower or motor power so as to produce different engagement conditions and transmission paths and thus to achieve the object of changing the gear ratio.
Taiwan Patent Publication No. 541828 and U.S. Pat. Nos. 6,189,395; 6,244,124; 6,626,057; and 6,366,343, which respectively correspond to Taiwan Patent Publication Nos. 421401; 426290; 462568; and 476213 have disclosed speed-changing mechanisms for scanners in order to provide required speeds for the scanners to perform a high-resolution scanning process and a low-resolution scanning process. However, these prior arts still have to change the speed with the extra motor power. A motor control circuit for an additional motor has to be provided in order to provide the power for changing the speed. Thus, the apparatus cost is increased, a relatively large space is occupied, and the power-saving requirement cannot be satisfied because the extra power has to be consumed.
Therefore, it is an important object of the invention to provide a transmission device capable of changing speed without an extra motor power source.

Transmission device capable of changing speed with stored energy


Methods and systems are provided for displaying scrollable information with an improved indicator of relative position. Certain embodiments may be use a focus element that indicates, by its relative position within the display, the relative position of the scrollable information displayed.

Often more content needs to be displayed on one "page" than will fit on a given screen. User interfaces overcome this by allowing users to "scroll" around a page in vertical and horizontal dimensions. However allowing users to scroll can create some additional problems. For example, at any given time a display needs to let the user know that they can scroll in a given direction. In that regard, the display needs to indicate whether a user may scroll up or down in the middle of a document, down at the top of a webpage, or left at the start of a spread sheet. The display may also need to inform the user of the current cursor position relative to the entire distance that can be scrolled. Additionally, a display may give the user "affordances" to actually scroll and manipulate the display (e.g. pressing "page down" key or click and drag the "thumb" on the scrollbar). Traditionally these problems have been overcome with traditional "scroll bars" at the side however these may be inadequate for a variety of reasons.
Traditional scroll bars use up valuable screen real estate and prevent the user from reading the content and monitoring the relative position at the same time. In the context of a mobile device the problem of screen real estate becomes even more critical because your physical screen is small (even if your resolution increases). Additionally, a user's eye must (and typically does) jump from the content in question to the scroll bar. This jumping of focus point back and forth slows down interaction and puts additional strain on the user's eyes.

Navigating displayed content on a mobile device


For a pixel of interest whose motion vector is not acquired in processing in the subsequent stage, motion vectors found for peripheral pixels around the pixel of interest in the processing in the subsequent stage, and evaluated values which represent the reliabilities of compensating candidate vectors, each consisting of a zero vector or the like, are calculated. The calculated evaluated values are compared, and a compensating candidate vector determined to have the highest probability is selectively acquired as the motion vector of the pixel of interest. The present invention is applicable to a signal processing apparatus for performing frame frequency conversion from a 24P signal to a 60P signal.

1. Field of the Invention
The present invention relates to image processing apparatuses and methods, and recording media and programs used therewith. In particular, the present invention relates to an image processing apparatus and method that increase the quality of an image based on motion vectors, and to a recording medium and program used therewith.
2. Description of the Related Art
In an image processing apparatus of the related art that converts the frame frequency on an image, by using, for example, the gradient method described in Japanese Unexamined Patent Application Publication No. 60-158786, block matching, or the like, a motion vector is detected and the detected motion vector is allocated to a generated interpolated frame. However, in the above motion vector detecting methods, motion vectors are not constantly detected. Accordingly, these methods may have a problem in motion vector reliability, such as inability to detect the motion vector of a pixel of interest, or unstableness of a detected motion vector.
In addition, when the detected motion vectors are allocated to the generated interpolated frame, the motion vectors are not allocated to all pixels in the interpolated frame.
The image processing apparatus copes with this case by maintaining a state in which a motion vector remains undetected or by setting the motion vector to a zero vector (i.e., a stationary state).
However, it may not always be said that the motion vector that remains undetected and the motion vector set to be a zero vector represents movement suitable for an object to which a pixel of interest belongs. Accordingly, when an image is generated by using the motion vectors, a problem occurs in that the above motion vectors cause no small visual deterioration such as discontinuity.
In addition, in many cases, motion vectors detected by the motion vector detecting method of the related art or motion vectors allocated to a pixel in the interpolated frame are found as motion vectors having no movement correlation (dissimilarity to peripheral pixels) although the motion vectors represent movements in the same object. Accordingly, there is a possibility that the motion vectors are found by error, that is, it is common that the motion vectors are not much probable.

Image processing apparatus and method, and recording medium and program used therewith


An extended Routing Policy Specification Language (RPSL) permits registry of independent routing policies for different Internet Protocol versions, while being compatible with existing RPSL. Address family identifiers (afis) for identifying a protocol version are inserted into attributes of objects that carry IP address prefixes. RPSL is also extended to permit separate handling of multicast routing policies in any protocol, by including subsequent address family indicators (safis).

To meet with the growing demand for Internet service, the Internet engineering task force (IETF) has introduced a standard for a next version of Internet Protocol (IP), generally referred to as Internet Protocol version 6, or simply "IPv6". Most of today's Internet uses IP version 4 (IPv4). The most important deficiencies in IPv4 identified by the IETF have been addressed, and are corrected in IPv6. Chief among these is the shortage of addresses. The number of IP addresses supported by IPv4 is expressible in 32 bits (i.e. 232=4,294,967,296). This number of addresses is not enough to support world-wide demand for Internet addresses.
IPv6 is expected to co-operate with IPv4 initially. It is also expected that eventually IPv4 will be phased out altogether, leaving only the IPv6. Accordingly, many details regarding co-operation of IPv4 and IPv6 have to be resolved. One important aspect of IP networks is related to routing policies. As is illustrated in FIG. 1, a typical Internet 8 includes a plurality of interconnected autonomous systems 10 (ASs) (only 4 illustrated) that respectively include routers, servers and the like, as well as a management interface 12. Each router in AS 10 is provisioned with a routing policy, that specifies handling properties for routes, etc. A network access point 14 (NAP) interconnects the ASs 10 and provides the management interfaces 12 with a single, co-operatively maintained, Internet routing registry database 16, well known in the art. The route registry database 16 provides for the exchange of policy information that makes inter-AS routing substantially less prone to error. Currently the language used to express routing policies is an object-oriented language called Routing Policy Specification Language (RPSL). RPSL is currently adapted to support only unicast IPv4 routing policies and cannot be used to specify routing policies for both IPv4 and IPv6, or for multicast traffic routing carried over either IPv4 or IPv6. As the demand for IPv6 increases, and more IPv6 ASs are deployed, the requirement for IPv6 routing policies increases proportionally. While it is possible to provide new, additional route registries and a new route specification language for IPv6, the inefficiencies of such a solution are not economical.
Consequently, there is a need for a method for extending RPSL to handle current needs facing AS management in relation to concurrent support of routing policies for both IPv4 and IPv6, as well as for multicast in either protocol, as described in part in an Internet-Draft that is a working document of the Internet Engineering Task Force (IETF), entitled "IPv6 Routing Policies using RPSL—draft-parent-rpsl-ipv6-00.txt" published by co-applicant Florent Parent on Oct. 17, 2001.

Multi-protocol route policy specification language


An electrokinetic pump capable of producing high pressure is combined with a nozzle having a submicron orifice to provide a high pressure spray device. Because of its small size, the device can be contained within medical devices such as an endoscope for delivering biological materials such as DNA, chemo therapeutic agents, or vaccines to tissues and cells.

The present invention is directed generally to a device that combines a miniaturizable high pressure pumping means and nozzle for generating a high pressure spray and particularly to a device for injecting DNA, chemotherapeutic agents, and vaccines into cells and tissues. Because of its small size the device can be incorporated into an endoscope or catheter, thereby providing non-invasive access to difficult to reach tissues, such as intestinal epithelium or the left ventricle interior wall, for therapy.
There is, at present, a great deal of interest in the medical technologies and biotechnology in applications that allow the insertion of genes into live eukaryotic cells and tissues. Two new areas of medical research, gene therapy, and DNA vaccines, that may have revolutionary impact of the practice of medicine, depend on such gene insertion techniques.
A surprisingly successful method for the introduction of DNA into cells has been the physical bombardment of cells and tissues with high-speed droplets or particles carrying DNA as discussed in Yang, N. S., and Sun, W. H., Nature Medicine, 1, 481-483, 1995; Johnston, S. A. and Tang, D. C., Methods in Cell Biology, 43, 353-365, 1994; Fynan, E. F. et al., Proceedings of the National Academy of Sciences of the United States of America, 11478-11482, 1993. In the first implementation of this technique (Sanford, J. C. et al., Part. Sci, Technol., 5, 27-37, 1987) the DNA was literally shot through the walls of the target cells. Although initially developed for use in plant cell lines, this approach has been found to result in significant levels of incorporation and expression of the DNA in a wide range of targets, including mammalian cells in culture, intact rat liver, and skin. The success of the strategy is surprising, not in the least, because it requires that cells remain viable after having submicron-size holes torn in their membranes, although it is not clear whether DNA must be ballistically transported into the cells, or simply the cells permeabilized to allow DNA on or around the cells to diffuse or be transported in. Other (seemingly more controlled) techniques for introducing DNA that are successful in vitro, such as single-cell microinjection, and electroporation, are not easily adaptable for clinical in situ gene therapy. Techniques that rely on vectors such as viruses or liposomes to deliver DNA to target tissues have other limitations, such as the need to find a vector that will target a certain tissue or cell type and will be specific to that cell type. If such vectors are injected, the region of transfected cells is not spatially localized (except by means of biological specificity). Bombardment methods have the advantage that they allow DNA to be introduced without the need for packing it in a vector, and the DNA can then be aimed (quite literally) at accessible target cells, though it is also possible to shoot viral particles into cells.
One effective means for DNA bombardment of cells is the use of a shock tube. In one example of such an instrument (Nabuisi, S. M., et al., Measurement Sci. and Tech., 5, 267-274, 1994), a membrane, located at the entrance of the tube, is ruptured by a high pressure gas to create a shock wave that impinges upon a secondary membrane at the other end of the tube. This secondary membrane is coated with DNA-containing particles, such as DNA adsorbed onto gold beads. When the shock wave hits it, the particles are accelerated to supersonic velocities and embed themselves in the target cells or tissues. Another simpler method is the use of a traditional jet injector (Haensler, J., et al., Vaccine, 17, 628-638, 1999), which consists in its most basic form of a spring-loaded plunger in a cylinder barrel with a small-aperture nozzle. When the plunger is suddenly released, the cylinder acts as a hydraulic intensifier, and a high pressure (e.g., 10 MPa) stream is emitted from the nozzle with velocities on the order of 140 m/sec. There is an apparent predominance of shock-tube or similar gas-driven methods in the scientific literature, probably related to their demonstrated efficacy for a variety of applications. This may in turn be due to the higher particle velocities that are achieved, allowing more cells to be permeated and deeper penetration into tissues and easier delivery of DNA through liquid layers and dead cells.
There is a long history of the use of jet injectors for intra/subcutaneous vaccinations (Hingston, R. A. and Hughes, J. G., Anesth. Analg. Cleve., 221-242, 1947). They are familiar, in some variant, to much of the population from their use in mass immunization programs. Shock-tube-based methods may also be used on skin as the target organ, or on surgically exposed tissues, as mentioned above. However, it is not straightforward to create a shock tube or high pressure gas feed system that can be safely used inside a body cavity or the cardiovascular system, and this factor limits the applicability of these strategies for introducing DNA into diseased tissues. Aside from the obvious pressure safety concerns, shock-tube methods would be precluded in the cardiovascular system, where any gas release would be unacceptable. More fundamentally, miniaturization of jet and shock-based designs is problematical because of simple hydrodynamic scaling issues. For example, to maximize nozzle velocities of jet injections, is it desirable to have a large diameter cylinders in order to minimize 0-ring frictional losses and pressure drop in the barrel. For constant nozzle velocity, these losses increase as the inverse square of the barrel radius, and gas flows in small diameter tubes have similar problems.
Consideration of the above discussion leads to several design features that should be met by a miniaturized DNA delivery device for internal use, in addition to demonstrated efficacy for performing DNA transfer:
1) The principle of operation should be such that performance does not deteriorate as the device is miniaturized, and the device should fit in the endoscope lumen (approximately 0.5 cm in diameter).
2) No high pressure gas supply lines that would have to run along the endoscope.
3) Only physiologically compatible fluids or particles released, with no release of gases.
4) Injection velocities should be substantially higher than that of jet injectors.
5) Power must be supplied by small wires that could be fit into an endoscope or catheter.
6) The device must be sterilizable.
7) The device should allow arrays of nozzles to be used.
8) The device should be able to be manufactured as a disposable item.
The present invention makes use of miniature high pressure pump technology combined with a nozzle having a sub-micron aperture or orifice to provide a novel device for delivering high pressure sprays at low flow rates, generally, and for direct gene/DNA delivery into cells that is suitable for clinical use on the end of an endoscope or catheter, in particular. Thus, in contrast to prior art devices for introduction of DNA into cells, the present device provides for direct genetic manipulation of difficult to access tissues, such as intestinal epithelium or the left ventricular wall, through relatively non-invasive means and thus, enhances the ability to address diseases of major importance such as heart disease and cancer of the alimentary tract. Further, the novel device disclosed herein is also generally useful for microinjection of chemo-therapeutic agents or vaccines into skin and other tissue. Furthermore, the inventive device has no moving parts, is constructed of simple materials, is compatible with micromachining such that inexpensive mass production is possible, releases only very small amounts of gas, provides injection velocities substantially higher than prior art devices such as jet injectors, and is sterilizable.
Generally, the inventive device integrates a high pressure electrokinetic pump (EKP) with a micro-nozzle, i.e., a nozzle having an aperture or orifice whose opening is sub-micron in diameter, for the delivery of a high pressure, low flow rate spray, including delivery of DNA or other biological materials into tissues. It has been demonstrated that the EKP is capable of providing levels of very high pressure ( greater than 104 psi or 100 Mpa) at low flow rates. Thus, the present device can evolve higher pressures than prior art spring-actuated devices or even shock tubes. Moreover, by using an EKP for pressure generation, the need for high pressure lines is obviated and thus the pressure losses that are encountered in prior art devices that transport hydraulic power from the pressure generator to the point of use are eliminated.

Electrokinetically pumped high pressure sprays


Described is an apparatus which comprises: a first memory unit having an input and an output, wherein the first memory unit operates on a first power supply which is operable to be turned off; a second memory unit having an input coupled to the output of the first memory unit, and an output, wherein the second memory unit operates on a second power supply which is always on; and a control logic coupled to the first and second memory units, the control logic to provide one or more control signals to each of the first and second memory units.

Synchronizers are logic units which are used to synchronize data between two different clock domains so that data can be transferred from one clock domain to another. Synchronizers are used to resolve meta-stability as quickly as possible. Synchronizers tend to use large devices and extra clock buffering to achieve lower "Tau." "Tau" is a measure of how quickly meta-stability is resolved i.e., how quickly a sequential unit can decide what the data is when a race condition exists between clock and data. Large sized device usage in a Synchronizer lowers "Tau" at the expense of capacitance on storage nodes of the Synchronizer. These storage nodes are generally critical nodes that hold the state of the sequential unit or latch. Extra capacitance on the storage nodes degrades speed and performance of the Synchronizer.
Even a small change in "Tau" can have a big impact on MTBF (Mean Time Before Failure). Furthermore, reset logic in the Synchronizer memory units (e.g., inside latches, flip-flops) adds devices and hence capacitance to storage nodes. This extra capacitance increases "Tau" and leakage power. On the other hand, state retention and low power objectives demands smaller devices and device stacking to reduce leakage power. It is challenging to incorporate state retention capability into the conventional Synchronizer because smaller devices increase "Tau" (and hence MTBF) while they reduce leakage.

Low leakage state retention synchronizer


In an information processing apparatus (10) that includes a cache memory (560) formed from at least one hierarchy, and a pre-fetch command that speculatively transfers data or a command from a main storage (30) to the cache memory, a cache controller (510) provides control to execute the pre-fetch command such that a virtual address is converted to a physical address using a conversion table, and the virtual address and the physical address are stored as a pair if the conversion succeeds.

1) Field of the Invention
The present invention relates to an information processing apparatus and a software pre-fetch control method that can effectively pre-fetch commands if a translation look-aside buffer (TLB) formed from plural hierarchies exists.
2) Description of the Related Art
In recent years, performance of information processing apparatuses has been improving remarkably, and the number of commands that can be executed per unit time is increasing considerably, year after year. In contrast, the speed of accessing main storages are not improving that much, and there is the problem that a long processing wait time arises when the information processing apparatus fetches or stores data in the main storage.
To overcome this problem, a technique is widely being employed in which a cache memory, having smaller capacity but larger access speed than the main storage, is provided between the information processing apparatus and the main storage. In accessing the main storage, localization is recognized, and regions of the main storage that are accessed frequently are held in the cache memory. Consequently, the wait time during data access is minimum.
A pre-fetching technique also is used often to utilize the cache even more effectively. When data that does not exist in the cache is needed, that data must be transferred from the main storage to the cache. However, because accessing the main storage is slow, a processing wait occurs until the transfer is complete. Thus, pre-fetching is enabling the information processing apparatus to use data on the cache without generating a processing wait, by predicting in advance which data will be needed, and transferring the predicted data from the main storage to the cache in advance.
Japanese Patent Application Laid-open No. 2000-339157 Publication discloses a cache memory control apparatus and a computer system, which have plural types of pre-fetching commands, and which utilize these commands properly depending on the situation, to thereby carry out pre-fetching effectively while keeping the burden on the system to a minimum.
However, there are cases when pre-fetching cannot be executed effectively, even if the technique disclosed in Japanese Patent Application Laid-open No. 2000-339157 Publication is used. The problem lies in the conversion from a virtual address to a physical address.
Currently, virtual memories, which provide a virtual address space that is larger than the actual capacity of the main storage, are widely used in many systems. However, in such systems, the virtual address on the virtual address space must be converted to the physical address on the main storage when the main storage is accessed. The address conversion is also necessary at the time of executing software pre-fetching that is one type of pre-fetching.
When the virtual address is converted to the physical address, a conversion table, called a TLB, which is stored in a memory, must be referred to. Current TLBs are made to have many hierarchies in order to be higher-speed. When the hierarchy cannot be utilized efficiently, there are cases that the pre-fetching command breaks down and the software pre-fetching fails.

Information processing apparatus and software pre-fetch control method


A process for transferring toned images to an image receptor at low temperatures with improved back transfer characteristics.

Prolonged tack toners prepared from thermoplastic resins and a plasticizer are well known in the art. Upon heating the thermoplastic resin and plasticizer mixture, the mixture becomes tacky or sticky and remains tacky for a considerable time even after cooling. This property is known as delayed tack or setting and has been found useful in the preparation of adhesive compositions, as well as in thermography, to produce a master which is imagewise exposed by means of heat, toned, and the toned image is then transferred onto an image receptor to provide a copy of the original image. In the above-described process, the prolonged tack property is present in the form of a continuous film over an imagewise tacky element.
The prolonged tack toners and transfer process described above can be used to make four-color proofs. For example, in preparing a four-color proof consisting of cyan, magenta, yellow, and black, the cyan toner image is transferred to a receptor. The magenta toner image is then transferred to the same receptor, with the two images in register. The yellow image is then transferred and finally, the black image is transferred so that all four images are in register. However, if the transferred toned image on the receptor remains tacky when the next color is transferred, the image on the receptor can back transfer to the surface of the photopolymer surface of the next color, resulting in partial image loss from the receptor to the photopolymer. Back transfer problems and the resulting image loss are unacceptable in the printing industry.
U.S. Pat. No. 4,461,823, issued to Held on Jul. 24, 1984, describes multiple transfer of tacky image areas using prolonged tack toners wherein the toners can be prepared by combining a thermoplastic resin, e.g., polystyrene, with a plasticizer or a copolymer of methylmethacrylate (90)/methacrylic acid (10) and triphenyl phosphate plasticizer. A dye or colored pigment can be combined with the resin/plasticizer component. One of the main disadvantages with these toners is that it is difficult to transfer a toned image to an image receptor at low temperatures without getting some back transfer when transferring the next color.
U.S. Pat. No. 4,469,625, issued to Held on Sep. 4, 1984, describes prolonged tack toners for the preparation of electric circuits. Examples of organic polymers and plasticizers are described in column 1 and include polystyrene and N-cyclohexyl-p-toluenesulfonamide, poly(methylmethacrylate) (90)/methacrylic acid (10) and triphenyl phosphate. One of the main disadvantages using these toners is that it is difficult to transfer a sufficient amount of toner to an image receptor at a low temperature. Applicant's assignee's copending application, Ser. No. 07/422,361 filed Oct. 16, 1989, issued Aug. 13, 1991, as U.S. Pat. No. 5,039,588, describes a non-electroscopic prolonged tack toner comprising an organic, thermoplastic terpolymer, a solid plasticizer and optionally a colorant wherein said toner is suitable for transferring toned images at low temperatures to an image receptor. The toners can be used to make a four-color proof. The toned image is transferred to a receptor. However, on subsequent transfers back transfer of the previously transferred image is observed.
U.S. Pat. No. 4,869,996 issued to McCartin et al. on Sep. 26, 1989, describes an improved process for preparing negative images from a positive-type photosensitive element. The process utilizes two separate applications of contrasting toning materials in order to produce a negative image. Each application of toning material is carried out at a different temperature. The process can also be used to produce positive images as well as negative multi-layer, multi-color images.

Process for detackifying transferred toned images


A low-viscosity, high-softening point heavy hydrocarbon material having a viscosity-reducing amount of at least one biodiesel material dissolved in a heavy hydrocarbon, and a method for producing such low-viscosity, high-softening point heavy hydrocarbon material are disclosed.

Petroleum pitch competes with coal tar pitch in many applications where the pitch is used as a carbon source and/or as a binder. The critical properties that are evaluated when deciding what type of pitch to use include: (a) flow properties, as measured by softening point and/or viscosity, and (b) carbon yield, as measured by ASTM D 2488, Coking Value by Modified Conradson Carbon.
Another pitch property that is also becoming of increasing interest is the polycyclic aromatic hydrocarbon content. The U.S. Pat. No. 5,746,906 patent describes a coal tar pitch having a low polycyclic aromatic hydrocarbon content and a method of making such pitch where a high softening point coal tar pitch (softening point of 120-175° C.) was mixed with a low softening point petroleum pitch to make a binder pitch having a softening point of 107-114° C. and a polycyclic aromatic hydrocarbon content slightly above 15,000 ppm.
In the manufacture of coal tar pitch, if more low boiling point materials are left in the pitch product, the resulting product has a lower softening point and a lower viscosity. In the case of petroleum pitch manufacturing, a high softening point petroleum pitch can be "cut back" with a hydrocarbon liquid material to produce a petroleum pitch having a lower softening point and a lower viscosity at a given temperature. It has long been understood in the industry, that a relationship between the softening point and viscosity exists (i.e., if one were lowered, the other would be lowered also).
Generally speaking, for a given softening point/viscosity, a petroleum pitch will have a lower carbon yield than a coal tar pitch. However, despite a potentially lower carbon yield, petroleum pitch offers certain advantages over coal tar pitch. One advantage that petroleum pitch has over coal tar pitch is the significantly lower concentration of solids of the petroleum pitch material. It is desired in the industry to fine a way to improve the flow properties (i.e., decrease the softening point and viscosity) with minimum effect on the carbon yield of petroleum pitch.
In the past, many types of materials have been used to modify the flow properties of such petroleum products as pitch and asphalt. Historically, these have been petroleum based, non-oxygenated hydrocarbons such as diesel fuel or various types of fuel oils, kerosene or various cutback oils. However, the use of these solvent "cutback" materials often has a dramatic effect on the carbon yield of the petroleum pitch and may cause problems with flash point due to increased volatility of the final product.
Examples of viscosity modification of bituminous materials include the use of a fluoro or chlorofluoro derivative of lower alkanes, such as disclosed in Smith et al., U.S. Pat. No. 4,151,003. The halogen content of the final product is a concern. The viscosity of the heavy hydrocarbons is significantly cut by the halogens to allow transport of the heavy hydrocarbons such as by pipeline. However, the presence of halogens in the final product causes other problems unless the halogenated material is removed. In contrast, the viscosity modification of the present invention does not have this problem.
Still other methods include reducing the viscosity of heavy hydrocarbon oils by preheating a stream of heavy carbon hydrocarbon oil in a stream of gas, mixing under pressure, and passing through a nozzle to form fine oil droplets such that a strong shearing action is created as the heavy oil and gas are forced through an orifice, as described in Dawson et al. U.S. Pat. No. 5,096,566.
In other situations, such as hydrocarbon/water emulsions, various viscosity modified emulsions are described. For example, the Schilling U.S. Pat. No. 5,320,671 describes mixing a bituminous emulsion aggregate slurry with a cationic emulsifier prepared as a reaction process of a polyamine with polycarboxylic acid hydrides and a kraft lignin. Other emulsions are described in the Schilling U.S. Pat. No. 5,328,505, Holleran, U.S. Pat. No. 5,474,607, and Krivohlavek, U.S. Pat. No. 5,834,359. Still other dispersant/emulsions are described in Wallace, U.S. Pat. No. 2,686,728; Ljusberg-Wahren, U.S. Pat. No. 4,957,511; McDonald, U.S. Pat. No. 4,085,078; Haire et al., U.S. Pat. No. 4,877,513 (also generally described in the abstract Haire, B. UNITAR 5th International Conference (Caracas 8/4-9/91) Proceedings V2, 121-126 (1991)); and Ohzeki et al., U.S. Pat. No. 4,539,012.
While these references describe viscosity reduction of emulsions, such references are not be considered applicable to the current invention since the viscosity reduction disclosed herein is for neat hydrocarbons, not a hydrocarbon/water emulsion.
Therefore, there is a need to produce a viscosity modifier that is useful with petroleum pitches, but does not have the above described drawbacks associated with the viscosity modifiers currently in use.
In particular, there is a need for a viscosity modifier that provides improved characteristics to the pitch and the pitch end product.
There is a further need for a viscosity modifier useful with heavy hydrocarbons which provides improved safety features such as low volatility and low toxicity. In specific examples, i.e., petroleum pitch, there is a need for viscosity modification without having a significant effect on carbon yield.
Recently, the use of biodiesels, such as methyl esters of fatty acids derived from either soybean or animal fats have received some attention to augment diesel fuel supplies in the United States. Until the present invention, however, no one had thought to use oxygenated compounds, specifically esters, more specifically methyl esters and even more particular, biodiesel, as a viscosity reduction agent for heavy hydrocarbons regardless or origin, including, in particular, petroleum based hydrocarbons such as asphalt cements and petroleum pitch as well as coal tar derived heavy hydrocarbons.

Viscosity modification of heavy hydrocarbons


A computer-implemented method for predictive responses to internet object queries may include receiving a query from a client to evaluate a first internet object. The computer-implemented method may also include analyzing the query to predict a set of additional internet objects for which the client may subsequently request an evaluation. The computer-implemented method may further include transmitting an evaluation of the first internet object and of each additional internet object in the set of additional internet objects to the client. Various other methods, systems, and computer-readable media are also disclosed.

Consumers face an ever-increasing number of annoying and harmful intrusions as they use and navigate the Internet. The number of unsolicited bulk e-mails (also known as "spam") has grown consistently over the past decade, with some researchers now estimating that more than 80% of e-mail represents spam. Besides annoying consumers, spam e-mails consume precious network bandwidth and resources and may be used as a vehicle for propagating malware or committing fraud. Malicious and inappropriate websites may pose similar threats, and they may also cause difficulties for parents who wish to oversee the content accessed by their children.
Content-filtering vendors may spare consumers from many of these problems by maintaining databases identifying spam and malicious websites. When a consumer attempts to download or access an e-mail or web document, content-filtering systems installed on a consumer's computing system may query these databases for information to determine whether to filter out an e-mail or warn the consumer about the web document.
Unfortunately, traditional content-filtering systems may also have drawbacks. Each query may consume computing resources both on the consumer side and on the vendor side. Additionally, waiting for the result of a query before loading an e-mail or web document may add unwanted latency to the consumer's experience. Accordingly, the instant disclosure identifies a need for predictive responses to internet object queries.

Systems and methods for predictive responses to internet object queries


A method of tracking events and their sequences in a computer system and predicting the probability of future events using a data structure that represents the predictive nature of the system after an initial event correlating to an object in the system. The invention reduces memory requirements and computational complexity by partitioning a trie into subtries where each subtrie represents a set of sequences of events, statically limiting the size of the partitions by limiting the number of descendants below the node defining the partition, and refreshing parts of the set of children and releasing slots occupied by particular descendants when additional space is needed. In addition, each partition can be attached to the object which it represents and moved in and out of memory with that object. In this way, data structures which would otherwise grow as large as N.sup.O and which have a computational complexity of predictions on the order of O.times.N, where N is the number of objects modeled and O is the model order, will be limited in size to N which, in turn, limits the computational complexity to order O.

This invention was made with Government support under Grant No. N0001 4-92-J-1807 awarded by the Office of Naval Research. The Government has certain rights in this invention.
1. Field of the Invention
The present invention pertains generally to a method for efficiently tracking and predicting events in a computer system primarily for activities such as pre-fetching and replacement decisions in cache systems (e.g., file system buffer caches, distributed system event caches, and disk controller input/output (I/O) caches), and more particularly to reducing computational complexity and memory requirements by placing static limits on subtrie size and by paging subtries with the events with which they are associated. The invention also provides the basis for computationally efficient data compression.
2. Description of the Background Art
Finite multi-order context models for event prediction are widely used in data compression, and Prediction by Partial Match (PPM) is a well known method for such use. PPM maintains a data structure with a plurality of substructures based on the previously seen nature of a system. An example of such a data structure is a trie having a plurality of nodes in which each node represents a sequence of events that has occurred at least once. Each node can be thought of as representing an individual event that occurred after the sequence represented by its parent, and contains a count of the number of times that its sequence has occurred. As new events occur, the trie is updated by recording the sequence of events that have occurred. At any point in the stream of events, the next event can be described as occurring after the sequence of events that has just occurred. These sequences can also be considered as part of the system's current state and can vary depending upon the length of sequences chosen. For example, for the sequence of events CACBCA, the next event can be described as occurring after A, CA, BCA, CBCA, ACBCA or CACBCA. The length of these sequences is called their "order" and the sequences that describe the conditions under which the next event will occur are called "contexts." In the example above, the sequence BCA would be called a third order context. To prevent the trie from growing too large, the maximum order or length of the sequences tracked is generally limited. For example, where m is used to denote this limit, there would be a total of m+1 contexts (0 through m) that describe the file system's current state at any point in time. In order to update the trie and use it to determine future events, an array of pointers 0 through m is typically maintained to point to the current contexts (C.sub.0 through C.sub.m). With each new event seen, a new current state is determined by updating each context in this array to reflect the addition of the new event. A new C.sub.k is then generated by examining the children of the old C.sub.k-1, searching for a child that represents the new event. If such a child exists, then this context (or sequence) C.sub.k-1 has occurred before, and is represented by this child's node. In that case, the k.sup.th element of the array is set to point to this child's node and its count is incremented. If no such child is found, then this is the first time that such a context has occurred, and a child is created to represent this event and the k.sup.th element of the array is set to point to its node. An important property of the trie is that the frequency count for each current context is equal to the sum of its children's counts plus one. As each new context is generated, the children of that context, if any, are examined to determine how likely they are to be the next event. Using the relationship Count.sub.child /(Count.sub.Parent -1), a maximum likelihood estimation of the probability of the child's event occurring can be generated.
With the rapid increase of processor speeds, the bottleneck of input/output (I/O) and network system latency has become a critical issue in computer system performance. Standard least recently used (LRU) based caching techniques offer some assistance but, by ignoring any relationships that exist between system events, they fail to make full use of the information available. As an alternative to LRU-based caching techniques, data compression event modeling techniques such as PPM, described above, have been used to drive a virtual memory cache where a finite number of most probable items are pre-fetched. A significant problem with using models such as PPM, however, is that the size of the data structures needed for such a model can quickly become too large for many applications. The result is that space requirements and the associated computational complexity cause models such as PPM to be impractical in practice. As a result, in applications where the number of different possible events (e.g., letters of the alphabet or blocks on a disk) is large, such predictive methods have only seen limited success.
It is also known to accumulate frequency counts of files that fall within a window after each file access, and to use the frequency counts to drive a pre-fetching cache. Another known approach is to have the application program inform the file system which files to prefetch. This approach, however, requires the application programs to be modified and fails to make use of any relationships that exist across applications.
Therefore, there is a need for a method for predicting sequences of events using predictive models such as PPMbut without the inherent computational complexity or memory requirements. The present invention satisfies those needs, as well as others, and overcomes the deficiencies found in previouisly developed predictive techniques.

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