Tabs or stops are integrated into a membrane structure to prevent its snapdown. Features comprising two surfaces separated by a distance equal to the maximum desired range of movement are produced. When the two surfaces contact, the motion of the structure is arrested or greatly diminished by increasing its rigidity. For an electrostatically actuated MEMS structure, these features can be used to limit the range of motion such that pull-in or snapdown is avoided, greatly enhancing the reliability of the device. One key design feature is that the two contacting surfaces are maintained at the same electrical potential avoiding problems associated with electrostatic cavity discharge.

Microelectromechanical system (MEMS) membranes are used in a spectrum of optical applications. For example, they can be coated to be reflective and then paired with a stationary mirror to form a tunable Fabry-Perot (FP) cavity/filter. They can also be used as stand-alone reflective components to define the end of a laser cavity, for example. Optical surfaces, such as curved, binary, or diffractive surfaces, can be fabricated on the membranes to create movable mirrors and lenses.
The MEMS membranes are typically produced by depositing a membrane structure over a sacrificial layer, which has been deposited on a support structure. This sacrificial layer is subsequently etched away, or otherwise removed, to produce a suspended membrane structure in a release process. Often the membrane layer is a metal or silicon compound and the sacrificial layer can be polyimide, for example.
Typically, membrane deflection is achieved by applying a voltage between the membrane and a fixed electrode on the support or an air bridge structure, for example. Electrostatic attraction moves the membrane in the direction of the fixed electrode as a function of the applied voltage. This results in changes in the reflector separation of the FP filter, cavity length in the case of a laser, or lens/mirror position.
One chronic problem associated with MEMS membranes in general is stiction. Specifically, if deflected sufficiently to contact an adjoining surface, the membranes can xe2x80x9csnap-downxe2x80x9d or adhere to that surface because of atomic-level forces, for example. One example is a suspended membrane structure that is designed to provide out of plane motion using electrostatic actuation. If the applied voltage exceeds that required to deflect the membrane to its instability point (roughly one third of the initial gap), then the membrane can snapdown. If the atomic-level bonding forces exceed the restoring force of the membrane structure, the membrane will remain xe2x80x9cstuckxe2x80x9d to the fixed electrode. Another scenario that produces a similar result is triggered by an acceleration load, when the load is sufficient to deflect the membrane to its full extent, as in a shock test.
One path to solving stiction problems includes the addition of surface features and/or coatings to the membrane, or the stationary surface adjacent the membrane, to allow the membrane to recover from a snapdown event. The contact area between the two surfaces can be reduced so that the bonding forces are reduced. Roughening the surfaces is an example of this approach as is producing discrete protrusions on either surface. A number of risks, however, are inherent with this solution. Surface roughening is not appropriate for all applications. Stiction bumps can become damaged in the event of snapdown since the electrical potential across the electrostatic cavity will be discharged through the small contact area of the bump. This can lead to bump damage or bump welding.
Another path focuses on reducing the surface energy of contacting surfaces by using a chemical treatment. Antistiction coatings, however, do not appear to be a robust solution, merely incrementally improving the survivability of membranes to snapdownxe2x80x94the coatings can also be relatively slow acting. They may also be incompatible with required optical coatings, such as dielectric antireflective (AR) coatings or highly reflective (HR) coatings for example, or damage active semiconductor devices because of organic content.
The present invention concerns the integration of tabs or stops that prevent snapdown of a deflectable membrane structure. Features comprising two surfaces separated by a distance equal to the maximum desired range of movement are produced. When the two surfaces contact, the motion of the structure is arrested or greatly diminished. For an electrostatically actuated MEMS structure, these features can be used to limit the range of motion such that pull-in or snapdown is avoided, greatly enhancing the reliability of the device. One key design feature is that the two contacting surfaces can be maintained at the same, or near the same, electrical potential avoiding problems associated with electrostatic discharge.
The above and other features of the invention including various novel details of construction and combinations of parts, and other advantages, will now be more particularly described with reference to the accompanying drawings and pointed out in the claims. It will be understood that the particular method and device embodying the invention are shown by way of illustration and not as a limitation of the invention. The principles and features of this invention may be employed in various and numerous embodiments without departing from the scope of the invention.

Interference tabs for avoiding snapdown of optical membrane and fabrication process


The invention presents an equalizing device, a corresponding method and an optical signal with a frame structure for enabling the method. The equalizing device includes a first 2×2 MIMO equalizer configured to perform a first equalization on the digital signal, supported by a 2×2 MIMO channel estimation of the channel based on the digital signal. Further, the device includes a second 2×2 MIMO equalizer, arranged after the first equalizer and configured to perform a second equalization on the digital signal, supported by a State of Polarization (SOP) estimation of the optical signal based on the digital signal.

Amongst other technologies, OPGW cables have been used on overhead power transmission lines for grounding, in order to realize lightning protection. In addition to the grounding, the OPGW cables allow for a cheap deployment of optical fiber cables, which are placed in metal tubes in the center of the OPGW cables, and are shielded by one or more layers of armoring wires.
However, in recent years, field and laboratory measurements indicated that a magnetic field, which is generated along the axis of the conductors by a lightning induced current, changes the SOP of the light in the optical fiber very rapidly. This becomes an issue, especially when using coherent optical polarization multiplexed transmission schemes. An initial assessment of the potential impact on the tracking abilities of coherent digital signal processing (DSP) integrated circuits was made, and the SOP speed due to lightning strikes was estimated to be of the order of a few megaradians per second (Mrad/s).
Recent field trials confirmed this phenomenon, and measured SOP speeds up to 5.1 Mrad/s, although it was impossible to correlate the magnitude of the lightning induced current with the speed of the SOP change. Therefore, in recent laboratory experiments, systematic setups were developed, in order to measure the SOP on two types of OPGW cables under lighting induced currents up to and above 150 ka. Fast SOP speeds exceeding 8 Mrad/s were measured. In this respect, it is known from lightning modelling that 1% of negative first strokes of lightning show a peak current of at least 150 ka, and can even reach values up to 500 ka in some extreme cases.
Fast SOP changes are particularly an issue when using coherent optical polarization multiplexed transmission schemes with, e.g., 100 Gigabits per second (Gb/s) or higher. Since most commercial digital signal processors are designed to withstand SOP changes caused by mechanical vibrations, the SOP tracking capabilities are often only in the hundreds of kiloradians per second (krad/s). Therefore, the industry arrived at a consensus that lightning strikes into OPGW cables can lead to traffic interruptions in metro and long-haul networks.
Most DSP application specific circuits (asics) available in the market use 2×2 multiple input multiple output (MIMO) equalizers based on gradient algorithms, such as the constant-modulus algorithm or the decision-directed least-mean-square (DD-LMS) algorithm. Considering also other processing algorithms, it seems possible to design 100G DP-QPSK DSP-asics able to track SOP rotation speeds up to a few hundred of krad/s, covering most of the SOP transients occurring in buried fiber links and some cases of lightning. For higher-order Quadrature Amplitude Modulation (QAM), the SOP tracking capability of such DSP devices is drastically reduced.
While DSP based on 2×2 MIMO channel estimation improves the performance of the 2×2 MIMO equalizer, ultra-fast SOP rotation speeds due to currents induced by lightning on aerial fiber links cannot be tracked and compensated, unless unpractical training-overhead is used.

Equalizing device for compensating rapid state of polarization changes of an optical signal


A user device with a touch-sensitive display presents a user interface with multiple content options and detects, on the touch-sensitive display, a touch indicating selection of one of the multiple content options. The user device monitors a duration of the touch. The user device presents a first set of selectable options, associated with the one of the multiple content options, in response to determining that the duration of the touch exceeds the first time threshold, and presents a second set of selectable options, associated with the one of the multiple content options, in response to determining that the duration of the touch exceeds the second time threshold.

Network based multimedia applications can provide access to an ever-growing amount and variety of content, services, and equipment, such as broadcast television content, non-broadcast television content (often referred to as "cable" television content), on demand and pay-per-view content, wireless services, widgets, applications, social media, etc. Content may be supplemented with an increasing variety of related information and user options. For example, a single video program may be associated with detailed information relating to actors, production information, previews, reviews, ratings, photographs, deleted scenes/bloopers, and/or series context. Additionally, users may have multiple options to act upon a content option, such as, bookmarking, sharing, viewing, scheduling, rating, or commenting on particular content.
Presenting information and user options relating to content in a simple, accessible manner is becoming increasingly difficult as the number and variety of options increases. Existing user interfaces may provide one of a variety of menu formats that group menu items into categories and sub-categories. These user interfaces may require a user to "drill down" through multiple menus to select a desired icon or other item.


In an example, a system for applying an agricultural product includes a valve and a solenoid. For instance, the valve includes a coil that generates a magnetic flux. The system includes a valve controller. The valve controller is configured to measure one or more electrical characteristics of at least one of the coil or a dissipation element. In some examples, the valve controller determines an actual duty cycle of a valve operator of the valve using the measured electrical characteristics. The valve controller determines a magnetic flux correction, for instance based on a difference between the actual duty cycle and a specified duty cycle. The valve controller operates the valve operator according to the specified magnetic flux and the magnetic flux correction to guide the actual duty cycle toward the specified duty cycle.

An agricultural product (e.g., a fertilizer, carrier fluid, or the like) is optionally applied to a crop (e.g., one or more plants located in a farm field). In some examples, the agricultural product is applied with a sprayer system, for instance a sprayer mounted on a prime mover (e.g., a tractor, truck, all-terrain-vehicle, or the like). The sprayer system includes a valve, and the valve facilitates application of agricultural product to the crop (e.g., by spraying the agricultural product from a nozzle). In some examples, the valve is operated by a controller, for instance to translate the valve between an open position and a closed position. In the open position, the valve permits flow of the agricultural product through the valve. In the closed position, the valve does not permit flow of the agricultural product through the valve (e.g., between a valve inlet and a valve outlet). In some examples, the controller modulates the valve according to a duty cycle. The valve opens closes) in correspondence to the duty cycle of the modulation provided by the controller.


There is provided a software-defined networking, SDN, architecture network, comprising a first network node (100) and a second network node (300), the first network node being configured to transmit data packets comprising: user data packets belonging to two or more user data packet flows, the user data packets of each user data packet flow comprising user data plane information; and control data packets each comprising OSI layer 7, L7, information for controlling the processing by the second node of the user data packets of a respective one of the user data packet flows. The SDN architecture network further comprises an SDN architecture forwarding element configured to forward user data packets received from the first node towards the second node using forwarding information that links a forwarding address to information in an IP 5-tuple of a data packet. The forwarding element is further configured to selectively forward a control data packet received from the first node towards the second node by: receiving and storing L7 information and the forwarding information; performing deep-packet inspection of the received control data packet to extract the L7 information therein, and selecting the received control data packet for forwarding towards the second node when the received control data packet comprises L7 information matching the stored L7 information; determining information in the IP 5-tuple of the received control data packet; and, where the received control data packet has been selected for forwarding, forwarding said control data packet towards the second node using the forwarding information and the information in the IP 5-tuple of the control data packet. The SDN architecture network also includes a controller (620) configured to transmit the L7 information and the forwarding information to the forwarding element (610).

FIG. 1 is a schematic diagram illustrating some of the components in a "traditional" (i.e. non-SDN architecture) network. In this example, a first node 100 of a type "A" is arranged to communicate with a plurality of user terminals (by way of example, four such user terminals are shown, as UE1 to UE4) by any suitable means, e.g. via an IP backbone Core Network (CN) 200 that includes a Serving GPRS Support Node (SGSN). In this example, the first node 100 is statically connected to a second node 300 of a type "B" by a network 400 comprising one or more appropriately configured forwarding elements (e.g. routers and switches), or by physically connecting the first and second nodes, e.g. via point-to-point links. By way of example, the first node 100 is provided in the form of a Gateway such as a Packet Data Network Gateway (PDN-GW) or a Gateway GPRS Support Node (GGSN), which may, as in the present example, include a Policy and Charging Enforcement Function (PCEF). The second node 300 may, as in the present example, be provided in the form of a value-added service (VAS) node configured to provide a value-added service in the form of content filtering, which requires application service detection based on Deep Packet Inspection (DPI) of received user data packets. The second node 300 may alternatively or additionally provide another kind of VAS, such as HTTP Header Enrichment. Regardless of the type of VAS being applied, DPI technology is used to classify IP packets according to a configured tree of rules, assigning classified IP packets to one or more associated service sessions. As is well-known, Shallow Packet Inspection (SPI) refers to packet inspection up to OSI Layer 3 or OSI Layer 4, whereas DPI refers to packet inspection beyond the level of SPI, from OSI Layer 4 or 5 up to OSI layer 7. DPI has been standardized in 3GPP Rel11, in the so-called Traffic Detection Function (TDF), which refers to a stand-alone node. However, DPI functionality may, as in the present example, run collocated with PCEF.
To provide the value-added service to one of the user terminals UE1 to UE4, the first and second nodes 100 and 300 need to exchange between them user data packets conveying user data plane information (e.g. samples of a VoIP call, multimedia information, HTTP Requests and responses etc.) as well as control data packets conveying control signalling for managing the processing of data packet flows carrying the user data plane information. The control data packets may, for example, be exchanged using the RADIUS protocol, for purposes such as identification, authentication, authorization etc. In the present example, the RADIUS signaling is used by the second node 300 to retrieve relevant subscriber session parameters (e.g. a subscriber identifier such as IMSI, MSISDN, or another parameter such as the UE's location, etc.), specifically to identify the user or other relevant parameter and apply the corresponding content filtering functionality.
As the first and second nodes 100 and 300 are statically connected to each other by the network 400, all data packets (each being either a user data packet or a control data packet) will be forwarded from the first node 100 to the second node 300. This is illustrated in FIG. 1, where there are four different user sessions (relating to UE1, UE2, UE3 and UE4) and where RADIUS messages (R1, R2, R3 and R4) and user data traffic (D1, D2, D3 and D4) are all routed to the second node 300.
Software Defined Networking (SDN) is an emerging network architecture which addresses a shortcoming of the static architecture of conventional networks, namely that it is ill-suited to the dynamic traffic steering needs of today's packet backbone networks. SDN decouples the network control and forwarding functions, and logically centralizes network intelligence and state. This enables network control to be directly programmable, and the underlying infrastructure to be abstracted for applications and network services. In SDN, the control plane logic is handled by a logically centralised server (the so-called "SDN controller"), and the forwarding plane consists of simplified forwarding elements (so-called "OpenFlow Switches" (OFS) in the context of the OpenFlow protocol) that are programmed by the SDN controller.
Thus, in contrast to the "traditional" network architecture outlined above, SDN architectures provide the advantage of allowing the routing of information between the nodes to be configured, changed or otherwise managed in a dynamic and easy manner, by allowing the forwarding elements in the network to be dynamically and easily configured and adjusted. This SDN feature, in turn, provides the advantage (among others) of making it possible to modify the number of nodes of a certain type (e.g. increasing/decreasing the number of nodes of type "B" in the above example, according to dynamic criteria, such as usage of a certain service, availability/unavailability of certain control features, etc.) in an dynamic and easy manner.
One application of SDN is the dynamic service chaining of value-added-functions. In SDN, service chaining is a concept that refers to the forwarding of traffic of specific traffic types along a predefined set of service functions (VAS) called a "service chain". This implies that when a data packet enters the SDN domain, it has to be classified and, once classified, it can be forwarded to the next service function or to the gateway at the end of a service chain.
As per 3GPP 29.061, SGi is the reference point between the PDN-GW and the packet data network. The packet data network may be an operator external public or private packet data network or an intra-operator packet data network, e.g. for provision of IMS services. This reference point corresponds to Gi for 3GPP accesses.

Control signalling in SDN architecture networks


A method of identifying network faults includes receiving subscriber statuses of customer premises equipment (CPE) of a communication network represented as a tree having a root node and leaf nodes. Each leaf node corresponds to a CPE. For each CPE, the method includes: (i) determining a conditional probability of the subscriber status of the CPE for each sub-tree in the network tree; (ii) determining a joint probability of the subscriber status of the CPE for every sub-tree in the network tree; (iii) determining a joint probability of the subscriber status of the CPE for every residual tree in the network tree; and (iv) determining a Bayesian posterior probability of a cut at each leaf node, given the subscriber status of the CPE. The method further includes determining a network node status topology indicating node statuses of nodes of the network tree based on the determined Bayesian posterior probabilities.

Modern telecommunication networks typically contain many thousands of individual components that connect in complex ways to route traffic from a source to a destination. A common challenge in these networks is executing a rapid diagnosis of network faults so that the faults can be repaired before they significantly impact user experience. In typical deployments today, network engineers in network operations center wait for complaints from subscribers in order to become aware of a service issue. This can typically take several hours to occur, leading to outage for subscribers for hours or even days, significantly degrading the user experience.


Techniques are provided for measuring user-perceived client-side performance of network documents. Client-side performance data associated with a network document can be collected during the loading of the network document by a web browser of a client device, for example, by a browser-executable script. The collected performance data may include latency information respectively associated with a plurality of digital assets configured to be rendered by the network document. A subset of the collected performance data can be selectively provided. The selectively provided performance data may be associated with a subset of the plurality of digital assets that are configured to be rendered within an active portion of the network document. The active portion of the network document may indicate a current area of interest for a user of the client device such as a viewport. The selectively provided performance data may be used to improve user-perceived performance at the client device.

When a user accesses a network resource, such as a website, user-perceived performance associated with such access can contribute to the overall user experience with the network resource, thereby affecting user decisions and even the bottom lines of the service providers. For instance, a user who experiences long response time at a retail website may be unwilling to visit the website again. Accurate and timely measurement of website performance can facilitate the identification and resolution of performance issues. However, existing performance measurement techniques focus primarily on the server-side performance that fails to account for client-side performance. Even when client-side performance is measured, such measurement is typically static and does not track user-perceived website performance as the users dynamically interact with the websites.

Client-side measurement of user experience quality


A dynamic microphone unit includes: a diaphragm vibrating in response to received sound waves; a voice coil fixed to the diaphragm and vibrating in cooperation with the diaphragm; a magnetic circuit generating magnetism in a magnetic gap, the voice coil being disposed in the magnetic gap; a first air chamber defined adjacent to the reverse of the diaphragm; and a second air chamber defined behind the voice coil, the second air chamber being in communication with the first air chamber, an elastic thin-plate acoustic resistor being disposed in the second air chamber while having tensile force applied, at a position where the acoustic resistor limits the volume of the second air chamber and comes into contact with the voice coil within a maximum displacement of the voice coil.

Omnidirectional components of a dynamic microphone are controlled by resistance (resistance control). The dynamic microphone is therefore provided with an acoustic resistor disposed immediately behind a diaphragm to achieve flat frequency response.
FIGS. 7 and 8 illustrate a typical conventional dynamic microphone unit 200. As illustrated in FIGS. 7 and 8, a unit case 1 functions as a base of the microphone unit. The unit case 1 is a cylinder having a bottom surface. The unit case 1 has an inner cylinder 11 integrated thereto and extends from the top toward the bottom. A round flange 12 extends from the bottom of the inner cylinder 11 of the unit case 1 inward in the radial direction.
The inner cylinder 11 of the unit case 1 accommodates a magnetic circuit composed of the following magnetic circuit components. A dish-shaped yoke 2 fixed into the inner cylinder 11 is supported by the flange 12 of the inner cylinder 11. The outer surface of the circumferential wall of the yoke 2 is in contact with the inner circumferential surface of the inner cylinder 11. A disk magnet 3 fixed on the bottom plate of the yoke 2 has a smaller outer diameter than the inner diameter of the circumferential wall of the yoke 2. A disk pole piece 4 is fixed on the magnet 3. A ring yoke 21 is fixed on the top surface of the circumferential wall of the yoke 2. The pole piece 4 has substantially the same thickness as that of the ring yoke 21. The pole piece 4 and the ring yoke 21 are fixed so as to be substantially flush with each other. The outer circumferential surface of the pole piece 4 faces the inner circumferential surface of the ring yoke 21 with a proper gap to define a round magnetic gap. Most of these magnetic circuit components are contained in the inner cylinder 11. The top surface of the pole piece 4 is substantially flush with the top surface of the inner cylinder 11.
A magnetic flux from the magnet 3 returns to the magnet 3 through a magnetic circuit composed of the yoke 2, the ring yoke 21, the magnetic gap, and the pole piece 4. In other words, the magnetic flux traverses the magnetic gap. The magnet 3 has a smaller outer diameter than the outer diameter of the pole piece 4. An air chamber 9 having a larger width than that of the magnetic gap is defined between the outer circumferential surface of the magnet 3 and the inner circumferential surface of the ring yoke 21 below the magnetic gap. The yoke 2 has multiple through holes 22 at the bottom portion. The holes 22 connect the air chamber 9 to a space surrounded by the round flange 12 of the unit case 1.
The unit case 1 has a projection edge 14 along the outer circumference at the top. The unit case also has a concentric projection 13 inside the projection edge 14, the projection 13 having a height lower than the projection edge 14 on the top of the unit case 1. The circumferential edge of a diaphragm 5 is fixed on the top surface of the projection 13. The diaphragm 5 is a thin film composed of a material such as synthetic resin or metal. The diaphragm 5 includes a center dome 51 and a sub-dome 52 surrounding the center dome 51. The center dome 51 is a partial spherical shell. The sub-dome 52 has an arc-shaped cross section and extends along the circumferential edge of the center dome 51. The diaphragm 5 is fixed at its outer circumferential edge of the sub-dome 52, on the top surface of the projection 13. This enables the diaphragm 5 to vibrate in response to the sound pressure from received sound waves, in the anteroposterior direction (the vertical direction in FIG. 7) around the outer circumferential edge of the sub-dome 52 as a supporting node.
A voice coil 6 is fixed along a round boundary line between the center dome 51 and the sub-dome 52 in the diaphragm 5. The voice coil 6 is formed by winding a thin conductive wire and by fixing it into a cylindrical shape. One end of the cylindrical voice coil 6 is fixed to the diaphragm 5. The voice coil 6 is disposed in the magnetic gap while the outer circumferential edge of the sub-dome 52 in the diaphragm 5 is fixed to the projection 13 as described above. In this state, the voice coil 6 is separated from both the ring yoke 21 and the pole piece 4.
Near the obverse of the diaphragm 5, an equalizer 8 functioning also as a protector for the diaphragm 5 is fixed, at its circumferential edge, to the projection edge 14 of the unit case 1. The equalizer 8 has a ceiling surface having a dome shape in the center. A gap with a predetermined distance is defined between the ceiling surface and the center dome 51 of the diaphragm 5. The equalizer 8 has multiple holes 82 for introducing sound waves from the exterior to the diaphragm 5.
The bottom of the unit case 1 is closed to provide a relatively large air chamber 15 in the unit case 1. In the air chamber 15, an acoustic resistor 16 adheres to the bottom surface of the yoke 2. The flange 12 of the unit case 1 has a cylindrical inner surface. The inner surface of the flange 12 supports the outer circumferential of the acoustic resistor 16. The acoustic resistor 16 is composed of, for example, a thick-ply unwoven fabric. The acoustic resistor 16 is disposed adjacent to the reverse of the diaphragm 5. A space adjacent to the reverse of the diaphragm 5 is in communication with the acoustic resistor 16 through the magnetic gap, the air chamber 9, and the holes 22 of the yoke 2. The space adjacent to the reverse of the diaphragm 5 is also in communication with the air chamber 15.
The diaphragm 5 vibrates in the anteroposterior direction in response to a variation in the sound pressure from received sound waves. The voice coil 6 also vibrates in the anteroposterior direction in cooperation with the diaphragm 5. The voice coil 6 vibrates to traverse the magnetic flux passing through the magnetic gap. The voice coil 6 traverses the magnetic flux to generate electric power as audio signals in response to a variation in the sound pressure. A dynamic microphone unit 200 electro-acoustically converts the signals as described above. For example, audio signals are outputted from both ends of the voice coil 6 wired along the reverse of the sub-dome 52 to the exterior.
In such a configuration of the dynamic microphone unit 200, the space adjacent to the reverse of the diaphragm 5 is partitioned by the voice coil 6 into a space adjacent to the reverse of the center dome 51 and another space adjacent to the reverse of the sub-dome 52. In the dynamic microphone unit 200, these spaces are in communication with each other through magnetic gaps adjacent to the inner circumferential surface and adjacent to the outer circumferential surface of the voice coil 6. The sensitivity of the dynamic microphone unit 200 can be effectively improved by decreasing the widths of the magnetic gaps. In the dynamic microphone unit 200, the widths of the magnetic gaps are therefore as decreased as possible provided that the voice coil 6 does not come into contact with the pole piece 4 and the ring yoke 21. As a result, the space adjacent to the reverse of the diaphragm 5 is substantially partitioned by the voice coil 6 into the spaces adjacent to the reverse of the center dome 51 and adjacent to the reverse of the sub-dome 52, as described above.
The acoustic capacitance of the space adjacent to the reverse of the center dome 51 is referred to as Sc, and the acoustic capacitance of the space adjacent to the reverse of the sub-dome 52 to as Ss. The acoustic mass and the acoustic resistance of a gap between the inner circumferential surface of the voice coil 6 and the outer circumferential surface of the pole piece 4 are referred to as mgi and rgi, respectively. The acoustic mass and the acoustic resistance of a gap between the outer circumferential surface of the voice coil 6 and the inner circumferential surface of the ring yoke 21 are referred to as mgo and rgo, respectively. Sound pressure applied to the obverse of the diaphragm 5 is referred to as P1, the acoustic resistance of the acoustic resistor 16 disposed in the air chamber 15 of the unit case 1 to as r1, the acoustic mass of the air chamber adjacent to the obverse of the diaphragm 5 to as mo, and the acoustic capacitance of the adjacent air chamber to as So. The acoustic capacitance of the air chamber 9 between the inner surface of the circumferential wall of the yoke 2 and the outer circumferential surface of the magnet 3 is referred to as Sg. Accordingly, the acoustic capacitance Sc of the space adjacent to the reverse of the center dome 51 is connected to the acoustic capacitance Ss of the space adjacent to the reverse of the sub-dome 52 through the acoustic mass mgi, the acoustic resistance rgi, the acoustic capacitance Sg, the acoustic mass mgo, and the acoustic resistance rgo, as illustrated in FIG. 8.
FIG. 9 illustrates an equivalent circuit of the dynamic microphone unit 200 including the acoustic mass, the acoustic capacitance, and the acoustic resistance illustrated in FIGS. 7 and 8. The equivalent circuit of the dynamic microphone unit 200 illustrated in FIG. 9 includes the sound pressure P1, the acoustic mass mo, the acoustic capacitance So, the acoustic mass mgi, the acoustic resistance rgi, the acoustic resistance rgo, the acoustic mass mgo, and the acoustic capacitance Ss, which are connected in series. In the equivalent circuit of the dynamic microphone unit 200, connection nodes between the acoustic capacitance So and the acoustic mass mgi and between the sound pressure P1 and the acoustic capacitance Ss are connected to the acoustic capacitance Sc. In the equivalent circuit of the dynamic microphone unit 200, connection nodes between the acoustic resistance rgi and the acoustic resistance rgo and between the sound pressure P1 and the acoustic capacitance Ss are connected to the acoustic resistance r1 and the acoustic capacitance S1 connected in series. In the equivalent circuit of the dynamic microphone unit 200, the acoustic capacitance Sg is connected in parallel to the acoustic resistance r1 and the acoustic capacitance S1 connected in series.
As is apparent from the equivalent circuit of the dynamic microphone unit 200 in FIG. 9, a resonant circuit is defined by the acoustic mass mgi adjacent to the inner circumference of the magnetic gap partitioned by the voice coil 6 and the acoustic capacitance Sg of the air chamber 9. In the equivalent circuit of the dynamic microphone unit 200, another resonant circuit is defined by the acoustic mass mgo adjacent to the outer surface of the magnetic gap and the acoustic capacitance Ss of a space adjacent to the reverse of the sub-dome 52. The air chamber 9 has a small volume in comparison with that of the air chamber 15 occupying the lower half of the unit case 1. As is apparent from the equivalent circuit of the dynamic microphone unit 200, the acoustic capacitance Sg and the acoustic mass mgi readily resonate in cooperation. The resonance causes a peak in a specific frequency in the dynamic microphone unit 200 and leads to improper frequency characteristics.
In order to decrease the resonance, the volume of the air chamber 9 may be further decreased to minimize the acoustic capacitance Sg to a negligible level to prevent the acoustic capacitance Sg from resonating with the acoustic mass mgi. FIG. 10 illustrates such a configuration of a typical conventional dynamic microphone unit 300. In the dynamic microphone unit 300, an acoustic resistor 25 is disposed in an air chamber 9 between the inner circumferential surface of the circumferential wall of a yoke 2 and the outer circumferential surface of a magnet 3. In the dynamic microphone unit 300, the acoustic resistor 25 is shifted to so as to be in contact with the bottom surface of the yoke 2. In the dynamic microphone unit 300, an air chamber 9 is provided above the top surface of the acoustic resistor 25. This causes the acoustic resistor 25 to limit the volume of the air chamber 9, resulting in a significantly small acoustic capacitance Sg of the air chamber 9. The acoustic capacitance Sg is connected to an acoustic capacitance S1 through the acoustic resistance r1 of the acoustic resistor 25 and holes 22 of the yoke 2. FIG. 11 illustrates an equivalent circuit of the dynamic microphone unit 300. In the equivalent circuit of the dynamic microphone unit 300 illustrated in FIG. 11, the acoustic capacitance Sg is limited to a negligible level, i.e., a significantly small acoustic capacitance by the existence of the acoustic resistor 25, as described with reference to FIG. 10. The acoustic capacitance Sg is therefore omitted in FIG. 11. As described above, the dynamic microphone unit 300 illustrated in FIG. 10 can prevent resonance caused by the air chamber 9 to provide proper frequency characteristics not having a peak in an audible frequency band.
In order to dispose the acoustic resistor 25 in the air chamber 9 behind a voice coil 6 as described above to significantly decrease the volume of the air chamber 9, the acoustic resistor 25 must be disposed near the voice coil 6. If the acoustic resistor 25 is composed of a felt material, unwoven fabric, or an unwoven fabric material, fibers 251 of the acoustic resistor 25 partly rises as illustrated in FIG. 10. If the diaphragm 5 vibrates exceedingly, the voice coil 6 comes into contact with the fibers 251 to generate abnormal noise. In addition, the fibers 251 disturb vibration of the voice coil 6 in accurate response to sound waves to cause inaccurate electro-acoustic conversion. The dynamic microphone unit 300 therefore has a limited reduction in a distance between the acoustic resistor 25 and the voice coil 6. The dynamic microphone unit 300 also has a limited reduction in the acoustic capacitance Sg by a decrease in the volume of the air chamber 9. Even the dynamic microphone unit 300 having such a configuration therefore can prevent limited resonance caused by the air chamber 9.
The present inventor proposed a dynamic microphone including a voice coil having lead wires along the inner surface of a sub-dome of a diaphragm facing a ring yoke, and a magnetism generator circuit provided with amplitude restriction means that restricts the maximum displacement of vibration of the diaphragm toward a pole piece to a position at which the lead wires do not come into contact with the ring yoke (see Japanese Unexamined Patent Application Publication No. 2005-260306).
The present inventor also proposed a dynamic microphone including a voice coil having lead wires elastically held on a sub-dome through an elastic layer painted on the inner surface of the sub-dome of a diaphragm adjacent to the voice coil, so as not to break the lead wires even if the diaphragm is biased against a magnetism generator circuit (Japanese Unexamined Patent Application Publication No. 2006-019791).

Dynamic microphone unit and dynamic microphone


Bulk containers of unitary construction and bulk containers formed of separate parts that interfit with one another to form a unitary structure and an apparatus that lifts the containers from a first support surface and suspends them in queued relation to one another above a second support surface. The first support surface may be a loading dock and the second support surface may be the bed of a truck. A plurality of rearwardly extending hook members are positioned on opposite sides of the truck bed at the rearward end of the truck. The hook members rotate in a vertical plane, and lift the container members, one at a time, from the first support surface by engaging outer roller members that extend laterally from opposite sides of each container. The hook members deliver the containers to horizontally disposed chain members that extend the length of the truck bed on both sides of the truck. The track members are rotatably mounted and carry the suspended containers, by engaging plural inner roller members disposed on opposite sides of the containers, toward the front of the truck bed so that the entire truck bed may be filled with the bulk containers.

It has long been the common practice to use laborers to load and unload trucks. For heavy loads, mechanical devices such as cranes have long been used.
Due to the high cost and low efficiency of manual labor, several inventors have made efforts to provide self-loading trucks. Typically, self-loading trucks include vertical lifting chains to lift items from the ground or from a loading dock, and horizontal chains that carry the lifted objects onto the truck.
For example, Leroux U.S. Pat. No. 4,642,018 discloses a vertical lifting chain and a horizontal trolley chain for automatically loading a transport truck by means of suitable control means and motors that are built into the truck body.
Other U.S. Pat. Nos. showing self-loading trucks are 2,442,549 to Pearlman, 2,873,869 to Neaverson, 3,109,544 to Learmont and 2,211,721 to Gerosa. Moreover, German patent 1121550 also shows a structure of interest.

Bulk containers and apparatus for loading bulk containers onto a truck


For the production of acrylonitrile by ammoxidation of propylene, there is provided a catalyst capable of giving a high yield for a long period of time. In producing acrylonitrile by ammoxidation of propylene, there is used a metal oxide as a catalyst, which metal oxide contains iron, antimony, molybdenum, bismuth, potassium, an F element, a G element, an H element and silica as essential components in a specific composition ratio, and in which metal oxide iron antimonate exists as a crystal phase, provided that the F element is at least one element selected from the group consisting of magnesium, calcium, strontium, barium, manganese, cobalt, nickel, copper, silver, zinc and cadmium, the G element is at least one element selected from the group consisting of chromium, aluminum, gallium and indium, and the H element is at least one element selected from the group consisting of yttrium, lanthanum, cerium, praseodymium, neodymium and samarium.

The present invention relates to a catalyst suitably used for the production of acrylonitrile by ammoxidation of propylene, a process for producing said catalyst and a process for producing acrylonitrile by using said catalyst.
With respect to the production of acrylonitrile by ammoxidation of propylene, various catalysts suitably used therefor are disclosed. In JP-B-38-17967, there is disclosed an oxide catalyst containing molybdenum, bismuth and iron, and in JP-B-38-19111, there is disclosed an oxide catalyst containing iron and antimony. After that, studies have been extensively continued to improve these catalysts. For example, in JP-B-51-33888, JP-B-55-56839, JP-B-58-2232, JP-B-61-26419, JP-A-7-47272, JP-A-10-43595, JP-A-4-11805 and the like, there are disclosed one improvement comprising using another component in addition to molybdenum, bismuth and iron, and the other improvement comprising using another component in addition to iron and antimony.
Further, in using these catalysts for the ammoxidation reaction, it is proposed to carry out the reaction while supplying a molybdenum-containing material thereto in the ammoxidation reaction, thereby maintaining the catalyst efficiency. For example, in JP-B-58-57422, there is disclosed a process, wherein a particle formed by supporting a molybdenum-containing material on silica is supplied to a fluidized bed catalyst containing molybdenum, bismuth, iron, cobalt and others, thereby restoring the catalyst efficiency. In DE 3,311,521 C2 and WO 97/33863, there is disclosed a process, wherein molybdenum trioxide or a molybdenum compound capable of converting to said trioxide in a specific amount is supplied to a catalyst similar to that mentioned above. Also with respect to a catalyst containing iron and antimony, there is known a similar proposal, for example, in JP-B-2-56938 and JP-B-2-56939.
These catalysts of the prior arts are effective to improve a yield of acrylonitrile to a certain extent. However, further improvements of these catalysts have been requested. Particularly, these catalysts have not been sufficient in respect to repeatability in the production thereof, their structural stability and long-term stability of the yield of desired products. Also with respect to a catalyst containing iron and antimony, particularly a molybdenum component-enriched catalyst containing a crystal phase of iron antimonate, which is disclosed in JP-A-4-118051, it has been very important to improve those from an industrial point of view and therefore further investigation of these catalysts have been required. In addition, also with respect to the process comprising supplying the molybdenum component to maintain the catalyst efficiency, it is difficult to say that it is always effective. Even if the molybdenum-containing material is supplied, no effect can be observed in the case where a catalyst structure is markedly damaged. Further, even if loss of molybdenum is not so large, no effect can be exhibited in the case where lowering of the catalyst efficiency is mainly caused by change of the catalyst structure. It is finding that the catalyst to be applied itself should be stable and should have no extreme damage on its structure.
It has been desired to find a catalyst, which satisfies requisites such as further improvement of the yield of the desired acrylonitrile, superior long-term stability when used for the ammoxidation reaction, and long-term maintenance of its efficiency by the supply of a molybdenum-containing material. An object of the present invention is to solve these problems and particularly to improve the catalyst composition disclosed in JP-A-4-118051, thereby giving a catalyst more suitably used for the production of acrylonitrile by fluidized bed ammoxidation reaction. Another object of the present invention is also to improve the reaction processes disclosed in JP-B-2-56938 and JP-B-2-56939.
The present inventors have undertaken extensive studies to solve the above-mentioned problems. As a result, they found that a catalyst containing elements such as iron, antimony, molybdenum, bismuth and potassium etc. and iron antimonate within a limited composition region can exhibit a superior catalyst efficiency, and that the efficiency can be maintained for a longer period of time by carrying out the ammoxidation reaction while appropriately adding a molybdenum-containing material thereto.
The present catalyst composition is capable of giving a high acrylonitrile yield and stable in a catalyst structure. Still, in the case where such a catalyst is used for the ammoxidation reaction without interruption, a decrease of the acrylonitrile yield, which appears mainly due to escaping of the molybdenum component, may be observed. Since the ammoxidation reaction is carried out at a temperature exceeding 400xc2x0 C., it seems that the escaping of the molybdenum component at the time of reaction is inevitable in this kind of catalyst having a large molybdenum content. In this regard, the acrylonitrile yield was able to be maintained at a higher degree for a longer period of time by continuing the reaction while adding and supplying the molybdenum-containing material. According to the catalyst in accordance with the present invention, which is structurally stable, the yield of desired products can be more sufficiently restored by adding the molybdenum-containing material at the time of the ammoxidation reaction. Moreover, since the addition of the molybdenum-containing material at the time of the ammoxidation reaction can be repeated, the catalyst in accordance with the present invention can be used for a much longer period of time by such a repeated addition of the molybdenum-containing material.
The addition of the molybdenum-containing material may be carried out from an early stage of the reaction. In applying the catalyst to the ammoxidation reaction, it is general that a catalyst surface composition and a catalyst structure are optimized by means of a composition, a preparation method or the like. However, it is difficult to say that the optimization can be always realized. As the case may be, the yield of the desired product increases by addition of the molybdenum-containing material at the start of the reaction. This seems that the optimization of the catalyst surface composition and the structure thereof can be realized also with the aid of the molybdenum-containing material.
With respect to a conventional catalyst, the acrylonitrile yield has been insufficient as mentioned above, and it has been also insufficient to restore the catalyst efficiency even if the molybdenum-containing material is added on the grounds that the yield decreases owing to a long-term use. However, according to the present invention, there is provided a process capable of maintaining a high acrylonitrile yield for a long period of time.
That is, the present invention provides a process for producing acrylonitrile, which comprises using a fluidized bed catalyst of a composition represented by the following empirical formula in the production of acrylonitrile by ammoxidation of propylene. The present invention also provides a process for producing acrylonitrile according said process, wherein the ammoxidation reaction is carried out while supplying a molybdenum-containing material. Further, the present invention provides said fluidized bed catalyst and a process for producing said fluidized bed catalyst.
Fea Sbb Moc Bid Ke Ff Gg Hh Qq Rr Tt Ox (SiO2)y
In the formula, Fe, Sb, Mo, Bi and K are iron, antimony, molybdenum, bismuth and potassium, respectively; F is at least one element selected from the group consisting of magnesium, calcium, strontium, barium, manganese, cobalt, nickel, copper, silver, zinc and cadmium; G is at least one element selected from the group consisting of chromium, aluminum, gallium and indium; H is at least one element selected from the group consisting of yttrium, lanthanum, cerium, praseodymium, neodymium and samarium; Q is at least one element selected from the group consisting of titanium, zirconium, vanadium, niobium, tantalum, tungsten, germanium, tin and lead; R is at least one element selected from the group consisting of lithium, sodium, rubidium, cesium and thallium; T is at least one element selected from the group consisting of boron, phosphorus and tellurium; O is oxygen; Si is silicon; and affixes a, b, c, d, e, f, g, h, q, r, t, x and y are independently of one another an atomic ratio, provided that a is a number larger than 0, and when a=10, then b=5 to 60, preferably 6 to 30, more preferably 6.5 to 20, c=5 to 50, preferably 8 to 45, more preferably 10 to 40, d=0.15 to 5, preferably 0.2 to 3, more preferably 0.3 to 2.5, e=0.1 to 5, preferably 0.2 to 3, more preferably 0.3 to 1, f=2 to 35, preferably 3 to 30, more preferably 6 to 24, g=0.05 to 10, preferably 0.1 to 8, more preferably 0.3 to 4, h=0.05 to 10, preferably 0.1 to 8, more preferably 0.3 to 4, h/c is larger than 0.02, preferably 0.025 to 1, more preferably 0.03 to 0.5, q=0 to 10, preferably 0 to 8, more preferably 0 to 4, r=0 to 5, preferably 0 to 4, more preferably 0 to 2, t=0 to 5, preferably 0 to 4, more preferably 0 to 2, x is a number of oxygen in a metal oxide formed by bonding of said respective components, and y=20 to 500, preferably 25 to 200, more preferably 30 to 180; and in which iron antimonate exists as a crystal phase.
Embodiments of the present invention are explained in more detail as follows.
It is essential that the fluidized bed catalyst in accordance with the present invention contains iron, antimony, molybdenum, bismuth, potassium, the F component element, the G component, the H component and silica (SiO2) as essential components, and further contains iron antimonate as a crystal phase. If these components are not used in the above-defined composition range, the objects of the present invention cannot be accomplished.
The iron antimonate is a compound represented by a chemical formula, FeSbO4, which is disclosed in the above-mentioned JP-A-4-118051 and JP-A-10-231125, and the existence thereof can be confirmed by an X-ray diffraction of the catalyst. The iron antimonate is essential for improving an acrylonitrile yield and for qualification of physical properties of the catalyst. Bismuth is essential to afford a catalyst capable of increasing the acrylonitrile yield with high stability, and it is finding that there is a preferred composition region for that purpose. When potassium is too little, it may happen that by-products increase, thereby decreasing the acrylonitrile yield. Whereas, when it is too large, it may happen that the reaction rate decreases, thereby decreasing the acrylonitrile yield.
The F, G and H components serve for stabilization of the catalyst structure. When their amounts to be added are too small, the catalyst tends to become structurally unstable, and so there is a tendency that it becomes difficult to maintain a satisfactory acrylonitrile yield for a long period of time. When the amounts are too large, there is a tendency that the acrylonitrile yield decreases. As the F component, preferred is at least one element selected from the group consisting of magnesium, calcium, manganese, cobalt, nickel and zinc, and more preferred is a component containing at least nickel. As the G component, preferred is a component containing at least chromium. As the H component, preferred is at least one element selected from the group consisting of lanthanum, cerium, praseodymium, neodymium and samarium, and more preferred is a component containing at least cerium.
As the catalyst components, the above-mentioned Q, R and T components may be further incorporated. As the case may be, these can be added for the purpose of stabilization of the catalyst structure, improvement of oxidation reduction characteristics, control of acidity and basicity and others. As the Q component, preferred are zirconium, vanadium, niobium, tungsten and germanium. As the R component, preferred are sodium, rubidium and cesium, and particularly preferred are rubidium and cesium. If desired, the T component may be incorporated in a small amount for the purpose of improving the acrylonitrile selectivity, controlling the by-products or others.
The process for producing acrylonitrile in accordance with the present invention is carried out according to a fluidized bed reaction. Accordingly, the catalyst is additionally required to have physical properties suitable for the fluidized bed reaction. That is, it is additionally required that its bulk density, particle strength, attrition resistance, specific surface area, fluidity and others are suitable. For that purpose, silica is used as a carrier component.
For preparing the catalyst in accordance with the present invention, it is permitted to apply a process appropriately selected from those disclosed in the above-mentioned prior arts.
For preparing iron antimonate, various processes are proposed. For example, there are processes disclosed in JP-A-4-118051 and JP-A-10-231125, and a process to be applied may be selected therefrom. In the production of the catalyst in accordance with the present invention, it is important that iron antimonate is prepared in advance according to these processes, for example a process described in JP-A-10-231125, and thereafter is mixed with other catalyst component materials. The iron antimonate prepared may contain a small amount of an element other than antimony and iron. The existing iron antimonate serves for the improvement of acrylonitrile selectivity and physical properties of the fluidized bed catalyst.
Materials used for the molybdenum component include molybdenum oxide and ammonium paramolybdate, wherein ammonium paramolybdate is preferably used. Materials used for the bismuth component include bismuth oxide, bismuth nitrate, bismuth carbonate and bismuth oxalate, wherein bismuth nitrate is preferably used. Materials used for the iron components include iron nitrate such as ferrous nitrate (iron (II) nitrate) and ferric nitrate (iron (III) nitrate), and iron oxalate such as ferrous oxalate (iron (II) oxalate) and ferric oxalate (iron (III) oxalate), wherein preferred is the iron nitrate. Materials used for the potassium component include potassium nitrate and potassium hydroxide, wherein potassium nitrate is preferably used. Materials of the F, G and R components include respective oxides, hydroxides and nitrates, wherein preferred are nitrates, and materials of the H and Q components include respective oxides, hydroxides, nitrates, oxygen acids and their salts, wherein preferred are nitrates, oxygen acids and their salts. With respect to the T component, materials used for boron include boric acid and anhydrous boric acid, wherein anhydrous boric acid is preferably used, materials used for phosphorus include phosphoric acid such as orthophosphoric acid, and materials used for tellurium include metal tellurium, tellurium dioxide, tellurium trioxide and telluric acid. Materials used for silica include silica sol and fumed silica. It is convenient to use silica sol.
The iron antimonate can be blended with materials of other components to obtain a slurry. These catalyst materials are blended, and thereafter the resulting mixture is subjected to spray drying and calcination to obtain a desired fluidized bed catalyst. The catalyst materials are blended and, if necessary pH of the slurry was adjusted, and the resulting slurry is subjected to heat treatment and others thereby to be able to prepare a catalyst slurry. In preparing the catalyst slurry, preparation conditions such as a mixing means of the materials, temperature, pressure and atmosphere can be voluntarily determined. When the slurry is prepared by adjusting pH of the slurry to a relatively high degree such as 3 to 8, it is recommendable to add a chelating agent such as ethylenediamine tetraacetate, lactic acid, citric acid, tartaric acid and gluconic acid according to a process disclosed in Japanese Patent No. 2747920, thereby preventing the slurry from gelling. In the case where the pH is adjusted to a relatively low degree such as 1 to 3 to prepare it, it is not always necessary to add the chelating agent. However, when added in a small amount, good results may be obtained.
The thus prepared slurry can be dried by means of spray drying. A spray drying apparatus is not particularly limited, and may be a conventional one such as a rotary-disk type and a nozzle type. A slurry concentration of the slurry entering the spray drying apparatus is preferably from about 10 to about 40% by weight in terms of an oxide of the element constituting the catalyst. The catalyst materials can be granulated by means of the spray drying. A spray drying temperature is not particularly limited. In carrying out the spray drying, pressure and atmosphere can be voluntarily determined. These spray-drying conditions are determined so as to obtain a catalyst having a desired particle diameter as a fluidized bed catalyst.
After completion of the drying, calcination can be carried out to obtain a desired fluidized bed catalyst. In carrying out the calcination, calcination conditions such as a calcination means, temperature, pressure and atmosphere can be voluntarily determined. For example, the calcination can be carried out at 200 to 500xc2x0 C., and additionally at 500 to 700xc2x0 C. for 0.1 to 20 hours. A calcination atmosphere is preferably an oxygen containing gas. It is conveniently carried out in air, which may be used in combination with a combination of oxygen and nitrogen, carbonic acid gas, water vapor or the like. For the calcination, a box type calciner, a tunnel type calciner, a rotary calciner, a fluidized bed calciner and others can be used.
It is recommendable to adjust a particle diameter of the thus obtained fluidized bed catalyst to preferably from 5 to 200 xcexcm, more preferably from 20 to 150 xcexcm. Incidentally, the particle diameter used herein is not an average particle diameter of the whole particles, but a particle diameter of the individual particles.
In using the molybdenum containing fluidized bed catalyst for the production of an unsaturated nitrile, as mentioned above, it is known that the molybdenum-containing material is added during the reaction, thereby maintaining the yield of the desired product. However, such an effect cannot be expected to a sufficient extent unless such a process is applied to a catalyst having a stable catalyst structure. Since the catalyst in accordance with the present invention is structurally stable even when used for a long period of time at a temperature exceeding 400xc2x0 C., at which this kind of the ammoxidation reaction is carried out, the reaction can be continued while adding the molybdenum-containing material, thereby maintaining the yield of desired products equal or superior to those of the early stage. However, even when such a structurally stable catalyst is used, the molybdenum component evaporates little by little from the catalyst under a reaction condition, and maybe this causes damage of the catalyst structure. Accordingly, when the molybdenum-containing material is supplied, it is necessary that the molybdenum-containing material be supplied before it becomes impossible to restore such a damage of the catalyst structure.
The molybdenum-containing material used here includes metal molybdenum, molybdenum trioxide, molybdic acid, ammonium dimolybdate, ammonium paramolybdate, ammonium octamolybdate, ammonium dodecamolybdate, phosphomolybdic acid, and those obtained by supporting these molybdenum-containing materials with an inert substance or the above-mentioned catalyst. Of these, preferred are molybdenum trioxide, ammonium paramolybdate and those obtained by supporting these molybdenum-containing materials with an inert substance or the above-mentioned catalyst. Although the molybdenum-containing material can be used in a gaseous state or a liquid state, it is preferred from a practical point of view that these solid molybdenum-containing materials are used in a powder state. It is particularly effective to apply a process comprising using a molybdenum-enriched catalyst obtained by enriching the above-mentioned catalyst with the molybdenum-containing material. According to the process, molybdenum in the molybdenum-containing material added can be efficiently utilized, and troubles caused by precipitation of the molybdenum oxide in the system or other reasons can be avoided. For preparing the molybdenum-enriched catalyst, the process described in JP-A-11-33400 or the like can be applied.
These molybdenum-containing materials may be added in a reactor in a continuous or intermittent manner at intervals. The time of addition and an amount to be added may be appropriately determined in consideration of a relation between the yield of desired products and operation facility. The amount added at a time is preferably from 0.01 to 3% by weight, more preferably from 0.05 to 2% by weight, as molybdenum element based on the weight of the catalyst filled in a reactor. It is necessary to pay attention to the followings. When the molybdenum-containing material is added in a large amount in a time, it may happen that the substance wastefully escapes out of the reaction system, thereby resulting in useless consumption, and moreover the material precipitates or accumulates inside of the reactor or adheres to a heat exchanger, thereby causing operational problems. When it is added in an intermittent manner, a total amount of the molybdenum-containing material added may be within the range as mentioned above.
The ammoxidation of propylene is usually carried out at a reaction temperature of 370 to 500xc2x0 C. under a reaction pressure of from atmospheric pressure to 500 kPa using a feeding gas having a composition of propylene/ammonia/oxygen=1/0.9 to 1.3/1.6 to 2.5 (molar ratio). An apparent contact time is usually from 0.1 to 20 seconds. It is convenient to use air as an oxygen source, which air may be diluted with water vapor, nitrogen, carbonic acid gas, a saturated hydrocarbon or the like, or may be enriched with oxygen.

Method for producing acrylonitrile, catalyst for use therein and method for preparing the same


Each of groups each has a plurality of communication channels. There are generated signals to be transmitted via the respective communication channels in the groups. The transmitted signals are time-division-multiplexed into a data sequence for each of the groups. The data sequences are spectrum-spread in response to different spread code patterns respectively. A reserve time slot may be provided. In cases where a reduction of a received signal quality related to one of the communication channels is detected, the reserve time slot is used in transmitting the signal of said one of the communication channels.

1. Field of the Invention
This invention relates to a mobile communication system in which a base station and mobile stations can communicate with each other by radio.
2. Description of the Prior Art
According to the Japanese automobile telephone system using digital radio communication, digital modulation is of the .pi./4-shift QPSK (quadriphase shift keying) type, and a plurality of carriers are used. During the radio communication, each of the carriers is subjected to 3-channel TDM (time division multiplexing).
In Europe, a GSM (global system for mobile communications) system using digital radio communication has been studied for practical use. According to the GSM system, digital modulation is of the GMSK (Gaussian filtered minimum shift keying) type, and a plurality of carriers are used. During the radio communication, each of the carriers is subjected to 8-channel TDM.
Furthermore, in Europe, a DECT (digital European cordless telecommunications) system has been investigated for private radio data transmission and private radio speech transmission within a small zone. According to the DECT system, digital modulation is of the GMSK type, and a plurality of carriers are used. In addition, TDM/TDD (time division multiplexing/time division duplex) is used in which equal numbers (about 10 channels) of uplinks and downlinks are assigned to each of the carriers.
An investigation has also been given of other various communication systems in which a base station and terminal stations in a service area covered by the base station can execute speech or data communication with each other by radio in time division multiplexing.
Time division multiplexing is used because of its advantages over frequency division multiplexing which will be described in the following. The first advantage is that a transmission data rate is variable and thus a certain degree of the flexibility of communication channels can be provided. The second advantage is that radio communication between the base station and the terminal stations has a burst shape in time base (time axis) and hence it is possible to set an interval of time during which operation is unnecessary.
On the other hand, time division multiplexing has the following disadvantages. As the degree of multiplexing increases, a transmission frequency band required for radio communication widens so that an equivalent noise bandwidth at a receiving side increases. Consequently, with respect to equal received signal levels, a received signal quality drops. In addition, with respect to equal transmission powers, an effective service area narrows. Further, radio communication in the present service area tends to be subject to interference from terminal stations located in neighboring service areas.
The other disadvantage of time division multiplexing will be described hereinafter. With respect to maintaining the qualities of received signals in communication channels resulting from time division, communication channels of equal times, equal modulation types, and a same carrier tend to interfere with each other. In addition, the communication channels tend to be subject to interference from another narrow-band system.
To maintain an adequate quality of a received signal of each communication channel, it is necessary that the received level of a desired signal is greater than that of an interfering signal by about 10 dB or more.
Also, a CDMA (code division multiple access) system has been investigated. In the CDMA system, information bits to be transmitted are spread in spectrum so as to be multiplexed within a common carrier according to spread code patterns having ten bits to several thousands of bits. The degree of multiplexing is determined by the number of different spread code patterns.
The CDMA system has the following advantages. Communication is hardly affected by narrow-band interference, in addition, many communication channels can be provided within a common carrier.
It is generally difficult for the previously-mentioned prior art communication systems to simultaneously satisfy enabling communications with different data rates, maintaining acceptable fiexibilities of communication channels, a great resistance to narrow-band interference, and permitting a common carrier to be used by many users.
The prior art spread spectrum communication system using the spread code patterns has the following problem. In the case where the received level of a signal of a desired communication channel which is spread in spectrum according to a spread code is extremely lower than the received levels of other signals spread in spectrum with other spread codes, a received signal quality of the desired communication channel tends to be lowered.

Matsushita Electric Industrial Co., Ltd.


To provide a curing accelerator for an oxidatively polymerizable unsaturated resin which can decrease the amount of cobalt metal soap used and has curing performance equal to or higher than excellent curing performance of the cobalt metal soap, and a printing ink and a coating material using the same. A curing accelerator for an oxidatively polymerizable unsaturated resin including a manganese or cobalt complex (α) containing quinolinol compound ions represented by Structural Formula (1) as a ligand, and a printing ink and a coating material including the curing accelerator.

In a field using an oxidatively polymerizable resin as a structural component, such as a printing ink and a coating material, a drier is added as a curing accelerator for drying the resin. As the drier used in the ink or the coating material, a metal salt of a heavy metal such as cobalt, manganese, lead, iron, or zinc and various carboxylic acids (hereinafter, may be abbreviated as "metal soap") is generally used.
Particularly, a cobalt metal soap has excellent drying performance, however, in a case where a large amount thereof is used for obtaining higher drying performance, surface drying of an ink or a coating film may extremely rapidly proceed, and thus, the cobalt metal soap may be a reason of wrinkles or shrinkage. Therefore, as a method of obtaining high drying performance while preventing such wrinkles or shrinkage, a curing accelerator containing both of a cobalt metal soap and bipyridyl has been proposed (for example, see PTL 1). This curing accelerator prevented wrinkles or shrinkage and had high drying performance.
However, cobalt compounds are listed up in Group 2B of "possibly carcinogenic to humans" in the carcinogenicity risk list by the International Agency for Research on Cancer, and accordingly, carcinogenicity of the cobalt compounds is concerned. In addition, metal cobalt is a rare metal and supplying thereof is unstable, and accordingly, the price of the cobalt metal soap is high. Therefore, a curing accelerator having high drying performance in which no cobalt soap is used or a decreased amount of the cobalt metal soap is used is required.
As a method of preventing wrinkles or shrinkage without using the cobalt metal soap, a drying accelerator (curing accelerator) containing both of a manganese metal soap and bipyridyl is already proposed, before the curing accelerator is disclosed in PTL 1 (for example, see PTL 2). However, although the drying accelerator disclosed in PTL 2 is advantageous in that no cobalt metal soap is used, a drying time is increased in a case of being used as a curing accelerator of a printing ink or a coating material.
As a curing accelerator usable with a practical drying time, a use of both fatty acid manganese salt and specific amino alcohol has been proposed (for example, see PTLs 3 to 6), but curing properties comparable to those of the cobalt metal soap have not been obtained yet.
Meanwhile, as a curing catalyst of an oxidatively polymerizable compound including vegetable oil, a method of using a complex formed of a specific quadridentate ligand compound and metal has been proposed (for example, see PTL 7), and the vegetable oil is limited to a material containing 50% or more of phenol compounds such as anacardic acid, anagiganic acid, perranjic acid, ginkgotic acid, ginkgolinic acid, cardanol, cardol, methyl cardol, urushiol, thitsiol, renghol, and laccol, such as cashew nut shell liquid obtained from cashew trees. That is, a curing reaction using this complex occurs with a radical coupling reaction of a phenoxy radical generated due to dehydrogenation of a phenol compound, and accordingly, the complex cannot be used in a system including no phenol-based compounds. In addition, this complex has poor solubility in organic solvents, and thus, it is difficult to use the complex for compositions for general inks or coating materials. The complex is supposed to be formed in a system to cause a curing reaction, but it is necessary to use a material which is hard to handle outdoors, such as hydrogen peroxide water or ethylenediamine in the system, thereby causing poor versatility as well.

Curing accelerator for oxidatively polymerizable unsaturated resin, printing ink and coating material

Abstract: In the formula, R1 is any of a hydrogen atom, a hydrocarbon group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a hydroxyl group, an amino group, a nitro group, a nitroso group, a sulfo group, and a halogen atom, and n is an integer of 1 to 6.


A vertical cell is provided for receiving a nuclear fuel assembly having a bundle of fuel rods retained at the nodes of a regular lattice and a skeleton formed of two end pieces connected together by tie rods and grids spaced apart along the tie rods. The structure of the cell has a cross-section corresponding to that of the assembly to be received and carries mechanisms for retaining the grids and the lower end piece, and a comb mechanism for holding the rods at their nominal spacing. The comb mechanism comprises at least two sets of combs carried by a frame fixed to the structure. The combs of each set are guided on the frame, and jacks move them towards and away from each other in a direction transversal to the movement of the combs of the other set. One of the grid retention mechanisms comprises jaws pivotably mounted on the structure and connected to simultaneous control jacks which move the jaws between a position in which they release the grid situated immediately below the comb mechanism and another position in which the jaws grip the grid on all sides thereof.

1. Technical Field
The invention relates to a reception and dismantling cell for a nuclear fuel assembly of the type comprising a bundle of fuel rods retained at the nodes of a regular lattice by a skeleton formed of two end pieces connected together by tie rods and grids spaced apart along the tie rods.
When such fuel assemblies are removed from a reactor after irradiation, they must be stored in a swimming pool until the deactivation is sufficient to make it possible to remove the rods. It is desirable to reduce as much as possible the volume occupied by the elements of the assembly during deactivation so as to increase the storage capacity of the swimming pool.
2. Prior Art
An installation is already known (Beneck et al. U.S. Pat. No. 4,731,219) for separating a fuel assembly into a skeleton and rods, which form the most active elements, and consolidating the rods in the form of a bunch of jointing rods distributed according to a triangular lattice. The installation comprises a cell receiving the fuel assembly to be dismantled for successively removing an end piece then extracting the rods. The cell comprises a vertical structure with a cross-section corresponding to that of the assembly to be received, having mechanisms for retaining the grids and the lower end piece and a mechanism for holding the rods at their nominal spacing with combs movable between a position in which they are outside the assembly and a position in which the fingers of the combs are engaged between the rods, above the highest remaining grid after removal of the upper end piece.

Nuclear fuel assembly reception and dismantling cell


A method for picture coding and also in a corresponding method for the decoding of a picture. In the case of the first picture coding method, a digital picture is divided into at least two sections, which are then combined with one another before being coded. In this case, a combined pixel is generated in each case from the corresponding pixels in the sections to be combined, in such a way that the combined pixel is allocated an unambiguous type (A, B, C, D) which corresponds to the distribution of the pixel values in the pixel N-tuple of the corresponding pixels. The method for pixel coding can also be designed in such a way that two successive pictures of a picture sequence are, in the same way, combined with one another before being coded.

The invention relates to a method for picture coding and a method for picture decoding. The invention furthermore relates to a method for constructing a sub-picture data unit for an electronic apparatus, and also to an electronic apparatus. Apparatuses appertaining to consumer electronics, in particular, are considered as the electronic apparatus. Furthermore, the invention relates to a data carrier for use in an electronic apparatus.
The invention is based on a method for picture coding of the generic type of the independent claim 1. Various picture coding methods are known from video technology. The picture coding method presented here follows a picture coding method which is used to generate so-called sub-picture data units for DVD apparatuses. DVD playback apparatuses of this type are already commercially available and each contain a sub-picture decoding device (xe2x80x9cSub-Picture Decoderxe2x80x9d) which can process the abovementioned sub-picture data units. A description of the picture coding method used is found e.g. in the DVD standard xe2x80x9cDVD Specification for read-only discxe2x80x9d Part 3, Video Specification, Version 1.0, August 1996, Chapter 5.4.3 Sub-Picture Unit (SPU). The picture decoding method is also explained therein. A detailed description of the abovementioned sub-picture decoding devices is found in EP-A-0 725 541.
According to the DVD standard, the main application for sub-picture data units is e.g. the generation of subtitles on the screen of a television set. The subtitles are then inserted e.g. at the bottom edge of the picture. The bitmap data for a respective subtitle are then stored in the sub-picture data unit. In order to define the location of a subtitle on the screen and also in order to define a number of display characteristics, in particular colour, contrast, etc., simple graphical control commands are specified in the abovementioned DVD standard. Thus, in principle, sub-picture data units can also be used for other purposes, thus e.g. for operating instructions, operator guidance menus, animation pictures, intermission pictures, etc.
The essential parts of a sub-picture data unit according to the DVD standard consist in a data field for the bitmap data of the text to be displayed or, more generally, of the object to be displayed, and also in a second part in which so-called display control command sequences are stored which define the display location, the display time and also the display characteristics of the stored object. In the data field for the bitmap data, it is also perfectly well possible for a plurality of objects to be stored one after the other, which are each retrieved at different times.
If the intention is to provide a plurality of objects in a sub-picture data unit, then the DVD standard prescribes the instruction of respectively providing a corresponding area in the bitmap data field for each object. The bitmap data are then additionally subjected to run length coding in order to achieve picture compression and save memory space.
The object of the invention is to specify a picture coding method and a picture decoding method which allow the sub-picture data units on the one hand to be simplified and on the other hand to be modified such that memory space is saved yet the possibilities in respect of configuration are not impaired. The object set is achieved by means of the features of the independent claims 1 and 2 and also by means of the features of the independent claim 7.
In the case of the invention""s method for picture coding, a digital picture is divided into at least two sections. A respective number of picture sections are subsequently coded in a combined manner. In this case, a combined pixel is generated in each case from the corresponding pixels in the sections to be combined, to be precise in such a way that the combined pixel is allocated an unambiguous type which corresponds to the distribution of the pixel values in the N-tuple of the corresponding pixels.
In the case of a further picture coding method according to the invention, two or more successive pictures are coded in a combined manner in a corresponding way.
These methods can advantageously be employed very well whenever essentially only two different pixel values are allowed for the individual pixels in the picture sections or pictures. This is the case whenever e.g. text is intended to be displayed in the picture. The picture can then be divided into the pixel values xe2x80x9cOnxe2x80x9d and xe2x80x9cOffxe2x80x9d. The N-tuple of the corresponding pixels then appears such that either the xe2x80x9cOnxe2x80x9d value or the xe2x80x9cOffxe2x80x9d value holds true per element. An unambiguous pixel type is then allocated for the distribution of the xe2x80x9cOnxe2x80x9d/xe2x80x9cOffxe2x80x9d values. In the simplest case, two picture sections are combined with one another. Consequently, the N-tuple consists of a pair of pixels. This case is defined more precisely in claim 3. If again just the two pixel values xe2x80x9cOnxe2x80x9d and xe2x80x9cOffxe2x80x9d are allowed, it is necessary to define four different pixel types in accordance with the four different distributions of the pixel values in the respective pair of pixels.
Which pixel type is associated with which case is then defined more precisely in claim 4 for the four possible cases.
Although advantageous, with regard to the picture compression, it is not absolutely necessary for the picture sections that are to be combined to be combined with one another such that they overlap 100%. It is also perfectly allowable for the picture sections that are to be combined to be combined only in a partially overlapping manner, in which case absent pixels outside the overlap area are allocated the xe2x80x9cOffxe2x80x9d value. This measure is specified in claim 5. It has the advantage that, in this manner, the picture sections can be enlarged in the vertical direction in a simple way, without a great deal of memory space additionally having to be made available for this purpose.
The combination of two or more picture sections results in a single combined picture section comprising just as many pixels as an individual picture section. The pixel values or pixel types thus obtained can then also be subjected to run length coding for the purpose of further picture compression.
The invention likewise relates to a method for decoding a coded picture, see claim 7. This method for decoding is characterized in that a section with combined pixel values is decoded in a plurality of passes, in each pass one of the picture sections being reconstructed and different selection rules being employed in each case, which selection rules determine which value is to be assigned to a pixel in the corresponding pass. This method affords the advantage that the previously combined picture sections can be reconstructed without any losses, to be precise all of them one after the other in a plurality of passes, the same data record being accessed in each pass. As already explained above, the picture coding method allows, if appropriate, the saving of memory space for the picture to be displayed.
Advantageous measures, in particular with regard to the special case where only two picture sections or pictures are combined and the individual pixels in the picture sections can only assume the two possible values xe2x80x9cOnxe2x80x9d and xe2x80x9cOffxe2x80x9d, are mentioned in the dependent claims 8 and 9.
The invention furthermore consists in a method for constructing a sub-picture data unit for an electronic apparatus according to claim 10. The sub-picture data unit essentially comprises a data section having the pixel values for the sub-picture and a command section having display control command sequences. For such a method, it is advantageous if the data section having the pixel values for the sub-picture or the sub-pictures is divided into sections and coded in a combined manner, in the way specified in claims 1 to 6, and that a respective display control command sequence is then provided for the reproduction of the pixel values of one of the combined picture sections.
In this case, it is also advantageous if, in a display control command sequence for the reproduction of a picture section, a respective command is provided for defining the way in which the combined pixels are to be evaluated. For this purpose, in the case of DVD sub-picture data units, it is possible to utilize the commands SET_CONTR and CHG_COLCON defined in the DVD standard.
In order to distinguish four different pixel types from one another, in the application of DVD sub-picture data units, it is possible to use the pixel types xe2x80x9cBackground Pixelxe2x80x9d, xe2x80x9cPattern Pixelxe2x80x9d xe2x80x9cEmphasis 1 Pixelxe2x80x9d and xe2x80x9cEmphasis 2 Pixelxe2x80x9d defined in the DVD standard.
Furthermore, the invention consists in a corresponding method for processing a sub-picture data unit. In accordance with the general teaching of the invention, for the reproduction of a picture section/picture, the combined pixels for this section/picture are evaluated in a specific, defined manner. In this case, for the reproduction of further combined picture sections/pictures, the combined pixels for these sections are then evaluated two or more times in succession in different ways. In the application of DVD sub-picture data units, as already mentioned, the commands SET_CONTR and CHG_COLCON defined in the DVD standard can be used to define the way in which the combined pixels are to be evaluated. In order to distinguish between four possible pixel types, it is again possible to use the pixel types xe2x80x9cBackground Pixelxe2x80x9d, xe2x80x9cPattern Pixelxe2x80x9d, xe2x80x9cEmphasis 1 Pixelxe2x80x9d and xe2x80x9cEmphasis 2 Pixelxe2x80x9d defined in the DVD standard.
The invention also consists in an electronic apparatus which has a sub-picture data unit constructed according to a method of claims 10 or 11 for the purpose of displaying a picture section or a picture.
Finally, the invention consists in a data carrier for use in an electronic apparatus which contains stored in it a sub-picture data unit as specified in the invention""s method for constructing a sub-picture data unit.

Method for picture coding and decoding, and also method for constructing a sub-picture data unit for an electronic apparatus, electronic apparatus, and data carrier for use in an electronic apparatus

Abstract: A method for constructing a sub-picture data unit for an electronic apparatus, in particular an apparatus appertaining to consumer electronics such as e.g. a DVD apparatus, being intended, where such sub-picture data units are used. Accordingly, the invention furthermore relates to an electronic apparatus as well.


This invention is directed to a beautification practitioner's chair capable of reclining to a substantially horizontal position and having integrated storage that may include rearwardly sliding trays and/or drawers. The beautification practitioner's chair may include a seat, a seat back, at least one arm rest, a head rest, and a leg rest. Contained below the at least one arm rest is at least one compartment that is generally enclosed on its front, sides, top, and bottom, and is generally accessible through the rear of the compartment. Contained therein may be at least one tray, at least one drawer, and/or at least one storage container. The compartment is configured to provide integrated storage in the beautification practitioner's chair, and the beautification practitioner's chair is configured such that the seat back is capable of reclining to a substantially horizontal position.

Beautification practitioners are people who specialize in beautifying their clients. Beautification practitioners include anyone who provides the service of beautifying their clients. For example, beautification practitioners include estheticians, lash artists, tattoo artists, body piercers, cosmetologists, permanent make-up artists, body painters, or medical professionals such as doctors who provide medical procedures for beautification. The list provided above is non-exhaustive, as any person who provides the service of beautifying their clients are beautification practitioners as defined herein.
In performing this work, beautification practitioners generally need easy access to a client's skin in order to perform their services. However, many chairs used by beautification practitioners have significant drawbacks to both the client and beautification practitioner. For example, some beautification practitioners use general salon chairs. These general salon chairs may be uncomfortable for clients. For example, if the service provided requires a long period of time to perform, such as a tattoo, the client may be uncomfortable sitting for a long period of time while the beautification practitioner performs their service. Additionally, it may be difficult for the beautification practitioners to perform some of their services if the client is in a seated position.
Some beautification practitioners may use recliner chairs instead of salon chairs so that the beautification practitioner may easily access client's skin and facial features, while allowing the client to comfortably lay down flat on their back. However, due to the size of these recliner chairs, it is nearly impossible to keep the beautification practitioner's tools and other items needed for their services readily accessible. For example, should a beautification practitioner use a general recliner chair, the beautification practitioner's tools and storage for other items is generally on a separate table or in a separate cabinet. Thus, in order for the beautification practitioner to perform their services, the beautification practitioner would need to continuously get up and move in order to change tools or grab any other required items, thereby causing a large loss in efficiency in performing their services. As beautification practitioners generally perform services by appointment, any loss in efficiency such as this results in less clients seen, which results in less money the beautification practitioners can bring in.
As such, there is a need for a beautification practitioner's chair that allows a client to comfortably sit and/or lay down depending on the service needed. Additionally, there is a need for a beautification practitioner's chair that provides an integrated storage system which may have integrated drawers and/or trays, such that the beautification practitioner does not have to continuously move about the studio to change tools. Therefore, there is a need for a beautification practitioner's chair that is capable of reclining to a substantially horizontal position that also includes an integrated storage system that may have a tray and/or drawers that are easily accessible for beautification practitioners.


An image forming device and an operating method are provided. The operating method included outputting a notification indicating that a cartridge in an image forming device needs to be refilled with toner, in accordance with the notification, performing a preparatory operation for entering a refill mode when it is determined that an operation mode of the image forming device is to be switched to the refill mode for refilling the cartridge with toner, when the preparatory operation is completed, controlling the image forming device such that only an operation related to the toner refilling is performed according to the refill mode, and when the refill mode is terminated, switching the operation mode of the image forming device to a job mode for performing a predetermined job in the image forming device.

Generally, a copier or a laser printer performs copying or printing by using a powdered toner in a cartridge. Since the cartridge containing toner is a consumable but relatively expensive, the toner may be refilled into the cartridge.
Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, parts, components, and structures.

Controlling operation of image forming apparatus according to toner refill mode

Hewlett-Packard Development Company, L.P.