A loosely coupled multiprocessor computer includes an input/output control unit for fetching both a program and data derived from an external input device and also for outputting processed data to an external output device; storage for storing therein both the program and data inputted from said input/output control unit; process unit for sequentially executing a processing operation of the data based upon the program stored in the storage; and, a transmission medium for coupling the process unit, input/output control unit and storage with each other. In the loosely coupled multiprocessor computer, a serial transmission medium is employed as the transmission medium. A transmission control unit for performing both a conversion process between data to be transmitted, flowing through the serial transmission medium and the processed data, and also a transmission/reception process of the data to be transmitted via the serial transmission medium, is provided with the input/output control unit, storage and process unit. A unit process unit for controlling the input/output control unit, storage, and transmission control unit is provided with the input/output control unit and storage with the transmission control unit.

The present invention generally relates to an architecture for both a hardware and a software used within a computer, and more specifically, to a computer including a loosely coupled multiprocessor.
Conventional computers have been developed and have progressed in such a manner that elements are highly integrated and physical distances among the elements are reduced as much as possible in order to increase processing speeds of these computers.
In FIG. 8, there is shown a schematic block diagram of a basic construction of the conventional computer.
A computer 80 includes as five major devices, a calculation device 81, a control device 82, a storage device 83, an input device 84, and an output device 85. Further, both the calculation device 81 and the control device 82 are incorporated into a central processing unit (referred to as a "CPU").
The computer 80 with the above-described construction executes the following operations.
First, a program is read out from the input device 84, and then is stored into a program region within the storage device 83. The control device 82 sequentially reads out the programs stored within this storage device 83 one by one so as to be decoded, and thereafter sends various instructions to the input device 84, output device 85 and storage device 83 which are required to execute commands written in the programs.
When, for instance, the command of the program corresponds to a command (READ command and the like) for requesting a data input, the inputted data is stored into an input region within the storage device 83.
Also, when the decoded command corresponds to a calculation command, data to be calculated is sent to the calculation device 81 in which a predetermined calculation is carried out.
Furthermore, data to be outputted is stored into an output region of the storage device 83. In response to an output command (WRITE command), the data stored in this output region is outputted by utilizing the output device 85.
As previously described, the computer 80 fetches the commands stored in the storage device 83 one by one, and executes processing operations in accordance with the programmed sequence.
Various system arrangements have been proposed in order to increase reliability of the computer systems with employment of such computers.
Among these computer systems, there is a multiprocessor system. In accordance with the multiprocessor system, a plurality of processors (processing device including CPU as an element) constitute a system for commonly using a main storage device and a file. When malfunction happens to occur, if only failed devices, processors, or a troubled unit employed within the main storage device are isolated from the computer system, the computer system may continue the processing operations, although the processing capabilities of the data are lowered. As a consequence, such a multiprocessor computer system has better adaptability and therefore is suitable for constituting a large-scale on-line computer system.
This multiprocessor system may be further understood as one of parallel-processing computer systems.
"Parallel processing" operations imply that processing operations which have been performed by a single processor employed within the conventional computer, are performed in a parallel form by parallel-operating plural processors. As a result, highspeed processing operations may be realized.
As to the parallel processing operation, it may be subdivided into SIMD (Single Instruction Multiple Datastream; a single instruction and plural data method), and MIMD (Multiple Instruction Multiple Datastream; a plural-instruction and plural data method), depending upon arrangements of processors and processing methods.
The "SIMD" method is such a method wherein a plurality of processors execute plural data in synchronization with each other in response to the same instruction supplied from a central control device. Since each of the processors can parallel-execute the same instruction in this SIMD method, this method is suitable for such a case that similar types of calculations are performed for a large quantity of data.
In accordance with the MIMD method, on the other hand, each of the processors is independently operable, and a plurality of data processing operations are executed in an asynchronization mode in response to a plurality of different instructions. Since the respective processors are separately operated, control functions are provided within these processors. Also, communication networks to perform information exchanges among the respective processors are provided, which is similar to that of the SIMD method.
FIG. 9 is a schematic block diagram for representing a system arrangement of the MIMD method.
A processor (1) 911, a processor (2) 912, and a processor (n) 913 include an ALU (arithmetic logic unit) 914, a storage unit 915, a control unit (1) 914, a control unit (2) 917, and further a control unit (n) 918, respectively, and are connected to either a coupling network, or a shared memory 919.
A multiprocessor system which corresponds to an MIMD method, is constructed so that a large number of processors closely communicate with each other with employment of a highspeed coupling network and are operable in a parallel mode with better cooperation.
Then, the multiprocessor system is roughly categorized into two communication methods effected among the processors.

Computer equipped with serial bus-connected plural processor units providing internal communications


A videotext receiver receives textual and graphic data including control data, header data and main text data. The videotext receiver includes a RAM for storing the textual and graphic data of a plurality of programs in a received broadcast signal, a microprocessor having a header selector for selecting the header data in the textual and graphic data stored in RAM, and a memory for storing a plurality of the selected header data. The selected header data is displayed on a CRT in a list format.

1. Field of the Invention
The present invention relates to a videotext receiver which receives and decodes the textual and graphic data multiplexed for transmission with a normal television broadcast for display on a CRT or other display device.
2. Description of the Prior Art
Various multiplex television broadcasting formats have been considered in recent years to more efficiently utilize existing broadcasting bands. One of these is videotext, already a commercialized broadcasting service whereby news and weather reports, stock market information, and other information comprised of text and/or graphics can be received and displayed on a home television receiver.
A typical videotext broadcast receiver currently used in the above system to receive the textual and graphic data multiplexed with the television broadcast signal and to display this information on a home television receiver is described below with reference to FIG. 6.
FIG. 6 shows the construction of a conventional videotext receiver wherein element 1 is the text and graphic data decoder 1 which restores the textual and graphic data to a text and graphic image; element 2 is a microprocessor for controlling the textual and graphic data decoder 1; element 3 is a receiver circuit for extracting the textual and graphic data from the video signal as digital data; element 4 is a RAM that stores the received textual and graphic data and is used as the operating area of the microprocessor 2; element 5 is an ROM in which is written the program controlling the operation of the microprocessor 2; element 7 is a video display memory in which is stored the text and graphic image decoded by the microprocessor 2; element 6 is a display processor that synthesizes the text and graphic image stored in the video display memory 7 into an RGB signal; element 9 is a character generator used when the textual and graphic data is decoded into a text and graphic image; element 8 is an added sound decoder used to process the additional sound data included in the textual and graphic data; and element 10 is a keypad used to select the desired text and graphic data for display.
Reference number 20 is a television signal receiver, which is comprised of an antenna 21, a television signal receiver circuit 22, an audio demodulation amplifier 23, a brightness amplifier and color demodulator circuit 24, a video/voice selector 25 which selects or mixes the video sound signal or the RGB signal and added sound signal output from the textual and graphic data decoder 1, an audio amplifier output circuit 26, a video amplifier output circuit 27, a speaker 28, and a display 29 for displaying the video image.
The operation of a conventional videotext receiver constructed as described above is described below.
The television signal input from the antenna 21 is demodulated by the television signal receiver circuit 22 in the television signal receiver 20, and video and audio signals are thereby extracted. The video signal is input to the receiver circuit 3 of the textual and graphic data decoder 1, and the text and graphic data is extracted from the video signal. When the user operates the keypad 10 to select the desired text and graphic data program from the many text and graphic data programs received, a request is sent from the keypad 10 to the microprocessor 2. The microprocessor 2 accordingly selects the requested text and graphic data program, and converts the text and graphic data to a text and graphic image according to the program written in the ROM 5 and using the character generator 9 as may be required. The resulting text and graphic image is then stored in the video display memory 7. The text and graphic image in the video display memory 7 is synthesized as an RGB signal by the display processor 6, and any additional sound data contained in the text and graphic data is converted to the added sound signal by the added sound decoder 8.
At the same time, the audio and video signals demodulated by the television signal receiver circuit 22 are respectively input to the audio demodulation amplifier 23 and the brightness amplifier and color demodulator circuit 24 where they are processed and then output to the video/voice selector 25. The video/voice selector 25 switches and selects the video signal (RGB signal) and audio signal (the added sound signal) output from the text and graphic data decoder 1 when the user selects a videotext program, or selects the television video and audio signals when the user selects a regular television broadcast, and outputs the selected signals to the speaker 28 and display 29 via the audio amplifier output circuit 26 and video amplifier output circuit 27, respectively. The user is thus able to view the selected television program or videotext program on the display 29.
During videotext program reception, there is a delay from the time the user selects the desired program to the time that program is received and displayed on the screen. To eliminate this delay, conventional videotext receivers store the videotext program in memory.
In the videotext receiver shown in FIG. 6, the program number of the text and graphic data to be stored in the RAM 4 and the channel number of the television broadcast are selected by the user by operating the keypad 10. The microprocessor 2 then stores the selected videotext program in the RAM 4.
At this time the user may also use the keypad 10 to enter a memo so that the contents of the selected program can be easily identified later.
The microprocessor 2 stores the selected program number of the text and graphic data, channel number, and memos in the RAM 4. As controlled by the user with the keypad 10, the microprocessor 2 may also display on the screen a list of the text and graphic data program numbers, channel numbers, and memos stored in the RAM 4.
The user is then able to refer to this list of program numbers, channel numbers, and memos to quickly view any selected program with no delay in the display time.
However, in a videotext receiver of this type, the user must first work the keypad 10 to enter the program numbers, channel numbers, and memos for all desired programs in order to display on screen a list of the videotext program numbers, channel numbers, and memos stored in memory, and this data entry operation is both complicated and inconvenient.

Matsushita Electric Industrial Co., Ltd.


Cross-flow filtration systems and corresponding methods for separation particulate matter from liquids. A representative system includes a cross-flow filtration zone (24) in fluid communication with a particulate settling zone (30) and further includes a fluid inlet (14) in fluid communication with one of the zones and a process fluid outlet (20) and in fluid communication with the other zone. A fluid treatment pathway (28) extends from the fluid inlet (14), through the cross-flow filtration and particulate settling zones (24, 30) to the process fluid outlet (20). A filter assembly (26) is located within the cross-flow filtration zone (24) and comprises a membrane surface (44) that isolates a filtrate chamber (46) from the fluid treatment pathway (28), and the filtrate chamber (46) is in fluid communication with a filtered fluid outlet (16). A recirculation pump (Z) in fluid communication with the process fluid outlet (20) and fluid inlet (14). A pressurizable recirculation loop (A) comprises the fluid treatment pathway (28) and recirculation pump (Z) and the recirculation pump (Z) is adapted for driving pressurized through the recirculation loop (A). A feed pump (Y) is adapted to introduce feed liquid into the system (10); and an effluent outlet (18) in fluid communication with the particulate settling zone (30). The feed pump (Y), effluent outlet (18) and filtered fluid outlet (16) reside outside of the recirculation loop (A).

Various techniques have been utilized to separate suspended particles from liquids including coagulation, flocculation, sedimentation, filtration and cyclonic separation. For example, in a typical hydroclone embodiment, pressurized feed liquid is introduced into a conically shaped chamber under conditions that create a vortex within the chamber. Feed liquid is introduced near the top of a conical chamber and an effluent stream is discharged near the bottom. Centrifugal forces associated with the vortex urge denser particles towards the periphery of the chamber. As a result, liquid located near the center of the vortex has a lower concentration of particles than that at the periphery. This "cleaner" liquid can then be withdrawn from a central region of the hydroclone. Examples of hydroclones are described in: U.S. Pat. Nos. 3,061,098, 3,529,544, 4,414,112, 5,104,520, 5,407,584 and 5,478,484. Separation efficiency can be improved by including a filter within the chamber such that a portion of the liquid moving to the center of the chamber passes through the filter. In such embodiments, cyclonic separation is combined with cross-flow filtration. Examples of such embodiments are described in: U.S. Pat. Nos. 7,632,416, 7,896,169, US2011/0120959 and US2012/0010063.
Size and separation efficiency are limiting factors for any given separation system. For example, while flocculation and sedimentation techniques are relatively energy efficient, they typically require settling ponds and long separation times. Hydroclones offer a smaller footprint, but have higher energy demand and are less effective at removing small particulate matter. Cross-flow filtration systems are small and produce high quality separations but are prone to fouling and are energy intensive. New systems are sought which offer an improved balance of attributes including overall size and separation efficiency.

Cross-flow filtration system including particulate settling zone


The present invention relates to an improved process for the preparation of pure compound of Formula-II, which is an intermediate in the preparation of Aliskiren and further conversion of compound of Formula-II into Aliskiren or its pharmaceutically acceptable salts.

Aliskiren, (2S, 4S, 5S, 7S)-N-(2-carbamoyl-2-methylpropyl)-5-amino-4-hydroxy-2,7-diisopropyl-8-[4-methoxy-3-(3-methoxypropoxy)phenyl] octanamide having the Formula-I, a new antihypertensive has been developed which interferes with the renin-angiotensin system at the beginning of angiotensin II biosynthesis.

Aliskiren is marketed by Novartis as TEKTURNA® in the form of its hemifumarate salt in a once-daily formulation.
U.S. Pat. No. 5,559,111 discloses Aliskiren and related compounds along with the synthesis of Aliskiren.
Further U.S. Pat. No. 7,132,569, U.S. Pat. No. 7,009,078, U.S. Pat. No. 6,730,798 and U.S. Pat. No. 6,800,769 claims novel intermediates used in the preparation of Aliskiren and process for the preparation of Aliskiren, which are incorporated here for reference. U.S. Pat. No. 7,132,569 discloses compound of Formula-II, which is used as an intermediate in the preparation of Aliskiren and process for the preparation of the same.

In this patent the obtained compound of Formula-II is purified by flash chromatography.
As the Aliskiren comprises, 4 chiral carbon atoms, the synthesis of the enantiomerically pure compound is quite demanding. The intermediate of Formula-II is commercially important in the synthesis of Aliskiren as well purity of the said intermediate play a vital role to achieve pure Aliskiren. Therefore an improved process for the said intermediate is needed to obtain pure intermediate which helps to obtain pure Aliskiren.
Thus the present invention provides an improved process for the preparation of Aliskiren intermediates and further conversion into Aliskiren.

Process for the preparation of aliskiren


An articulated tracked vehicle that has a main section, which includes a main frame, and a forward section. The main frame has two sides and a front end, and includes a pair of parallel main tracks. Each main track includes a flexible continuous belt coupled to a corresponding side of the main frame. The forward section includes an elongated arm. One end of the arm is pivotally coupled to the main frame near the forward end of the main frame about a transverse axis that is generally perpendicular to the sides of the main frame. The arm has a length sufficiently long to allow the forward section to extend below the main section in at least some degrees of rotation of the arm, and a length shorter than the length of the main section. The center of mass of the main section is located forward of the rearmost point reached by the end of the arm in its pivoting about the transverse axis. The main section is contained within the volume defined by the main tracks and is symmetrical about a horizontal plane, thereby allowing inverted operation of the robot.

The invention relates to a robotically controlled mobility platform.
Robots are useful in a variety of civilian, military, and law enforcement applications. For instance, a robotically controlled mobility platform inspect or search buildings with structural damage caused by earthquakes, floods, or hurricanes, or inspect buildings or outdoor sites contaminated with radiation, biological agents such as viruses or bacteria, or chemical spills. The platform can carry appropriate sensor systems for its inspection or search tasks. Military applications include operations that are deemed too dangerous for soldiers. For instance, the robot can be used to leverage the effectiveness of a human "pointman." Law enforcement applications include reconnaissance, surveillance, bomb disposal and security patrols.
The mobility approaches that have been used in prior robotic platforms exhibit various shortcomings, many of which are addressed by the present invention.


Autostereoscopic display device comprising a backlight (66), a display panel (62) comprising rows and columns of pixels and a lenticular arrangement (60, 64), wherein the backlight (66) provides a striped output comprising stripes in the column direction or offset by an acute angle to the column direction the lenticular arrangement comprises a first lenticular lens array (60) on the side of the display panel (62) facing the display output for directing different display panel pixel outputs in different directions and a second lenticular lens array (64) on the opposite side of the display panel (62), facing the backlight (66), for providing collimation of the striped back-light output.

A first example of an imaging arrangement for use in this type of display is a barrier, for example with slits that are sized and positioned in relation to the underlying pixels of the display. In a two-view design, the viewer is able to perceive a 3D image if his/her head is at a fixed position. The barrier is positioned in front of the display panel and is designed so that light from the odd and even sub-pixel columns is directed towards the left and right eye of the viewer, respectively.
A drawback of this type of two-view display design is that the viewer has to be at a fixed position, and can only move approximately 3 cm to the left or right. In a more preferred embodiment there are not two sub-pixel columns beneath each slit, but several. In this way, the viewer is allowed to move to the left and right and perceives a stereo image in his/her eyes all the time.
The barrier arrangement is simple to produce but is not light efficient. A preferred alternative is therefore to use a lens arrangement as the imaging arrangement. For example, an array of elongate lenticular elements can be provided extending parallel to one another and overlying the display pixel array, and the display pixels are observed through these lenticular elements.
The lenticular elements are provided as a sheet of elements, each of which comprises an elongate semi-cylindrical lens element. The lenticular elements extend in the column direction of the display panel, with each lenticular element overlying a respective group of two or more adjacent columns of display sub-pixels.
If each lenticule is associated with two columns of display sub-pixels, the display sub-pixels in each column provide a vertical slice of a respective two dimensional sub-image. The lenticular sheet directs these two slices and corresponding slices from the display sub-pixel columns associated with the other lenticules, to the left and right eyes of a user positioned in front of the sheet, so that the user observes a single stereoscopic image. The sheet of lenticular elements thus provides a light output directing function.
In other arrangements, each lenticule is associated with a group of four or more adjacent display sub-pixels in the row direction. Corresponding columns of display sub-pixels in each group are arranged appropriately to provide a vertical slice from a respective two dimensional sub-image. As a user's head is moved from left to right, a series of successive, different, stereoscopic views are perceived creating, for example, a look-around impression.
The above described device provides an effective three dimensional display. However, it will be appreciated that, in order to provide stereoscopic views, there is a necessary sacrifice in the horizontal resolution of the device. This sacrifice in resolution increases with the number of views generated. Thus, a major drawback of using a high number of views is that the image resolution per view is reduced. The total number of available sub-pixels has to be distributed among the views. In the case of an n-view 3D display with vertical lenticular lenses, the perceived resolution of each view along the horizontal direction will be reduced by a factor of n relative to the 2D case. In the vertical direction the resolution will remain the same. The use of a barrier or lenticular that is slanted can reduce this disparity between resolution in the horizontal and vertical direction. In that case, the resolution loss can be distributed evenly between the horizontal and vertical directions.
Increasing the number of views thus improves the 3D impression but reduces the image resolution as perceived by the viewer. The individual views are each in so-called viewing cones, and these viewing cones repeat across the field of view.
The viewing experience is hampered by the fact that the viewers are not entirely free in choosing their location from which to view a 3D monitor or television: at the boundaries between viewing cones the 3D effect is absent and annoying ghost images appear. There is therefore a desire to have the viewing cones as wide as possible, for example so that a viewer can remain within a single central viewing cone and still be able to move position. However, designing the optical system to provide a wide viewing cone comes at the expense of either increased cross talk between the images of different views or a substantial loss of spatial resolution due to the generation of additional views. Furthermore, such an optical system can require a thick optical stack.
EP0 786 912 discloses an autostereoscopic display in which laterally overlapping viewing windows are provided to enable observer tracking.

Auto-stereoscopic display device with a striped backlight and two lenticular lens arrays


The present invention enables three-dimensional nanofabrication by isotropic shrinking of patterned hydrogels. A hydrogel is first expanded, the rate of expansion being controlled by the concentration of the crosslinker. The hydrogel is then infused with a reactive group and patterned in three dimensions using a photon beam through a limited-diffraction microscope. Functional particles or materials are then deposited on the pattern. The hydrogel is then shrunk and cleaved from the pattern.

The ability to assemble custom three-dimensional patterns of functional materials over millimeter scales with nanometer resolution would have wide-ranging impact in areas such as photonics and materials science1-5. One approach to this problem would be to assemble the material at a more accessible length scale before shrinking it to the desired size. All shrinking methods to date have either been anisotropic6-8, or have relied on compositional changes in the substrate under extreme conditions9, which limits the range of functional materials that can be used. Here, inspiration is drawn from the coil-globule transition in polymers: hydrogels are known to undergo volumetric phase transitions in response to mild environmental changes that alter the balance of interactions between polymer chains and the solvent10-12. However, to date, the isotropy of this shrinking process has not been characterized.
Therefore, it would be desirable to have a method wherein precision millimeter to nanoscale fabrication is enabled through three-dimensional patterning of hydrogels with functional materials through the use of diffraction-limited microscopy and optionally, sizing of the patterning through isotropic shrinking.

Three-dimensional nanofabrication by patterning of hydrogels


A blower impeller includes a substantially cylindrical cup portion, and a plurality of blades arranged on an outer circumferential surface of a circumferential wall portion of the cup portion. The cup portion includes on an inner circumferential surface of the circumferential wall portion thereof a plurality of axially extending first ribs and a plurality of second ribs arranged between the first ribs. The first and second ribs are arranged in a circumferential direction. A virtual envelope joining radially inner end portions of the first ribs has a smaller diameter than that of a virtual envelope joining radially inner end portions of the second ribs.

1. Field of the Invention
The present invention relates to the structure of an impeller. More specifically, the present invention relates to an impeller for use in a blower.
2. Description of the Related Art
In conventional blowers (blower fans), a motor is arranged inside a cylindrical impeller cup to rotate an impeller with a plurality of blades. The motor includes a stator portion and a rotor portion supported so as to be rotatable with respect to the stator portion. A cylindrical rotor holder is press-fitted to an inner circumferential surface of the impeller cup, so that the impeller is fixed to the rotor holder.
When the rotor holder is press-fitted to the entire inner circumferential surface of the impeller cup, a significantly uneven shape of the rotor holder or the impeller cup leads to an excessive pressure being applied to a portion of the impeller cup, which will result in a breakage of the impeller cup.
JP-A 2008-69672 describes a technique used to overcome the above problem. According to the technique described in JP-A 2008-69672, a plurality of axially extending ribs are arranged in a circumferential direction on the inner circumferential surface of the impeller cup, and the rotor holder is press-fitted to an inside of the impeller cup while also being pressed against a top portion of each rib, so that the impeller is fixed to the rotor holder. According to this technique, when the rotor holder is press-fitted to the impeller cup, the aforementioned excessive pressure due to the uneven shape of the rotor holder or the impeller cup would be absorbed by elastic deformation of the ribs to prevent the breakage of the impeller cup.
The number of blades of the impeller is determined based on the purpose or intended use of the blower or the like. For purposes of cooling an electronic device, such as a server, which is densely packed with components, for example, the blower is required to be capable of providing high static pressure. For the purposes of providing high static pressure, blowers (cooling fans) having an impeller with a small number (e.g., three to five) of blades are suitable. Thus, fans having an impeller with a small number of blades are frequently used in accordance with such demand.
FIGS. 1A, 1B, and 1C are perspective views each illustrating the structure of an impeller with a plurality of blades 102 attached to an outer circumferential surface of an impeller cup 101. In FIG. 1A, the impeller has seven blades 102. In FIG. 1B, the impeller has five blades 102. In FIG. 1C, the impeller has three blades 102. As is apparent from FIGS. 1A to 1C, as the number of blades 102 decreases, the inclination of each blade 102 with respect to an axis of the impeller cup 101 becomes greater, and the length of a root portion 102a of each blade 102 at which the blade 102 comes in contact with the outer circumferential surface of the impeller cup 101 becomes greater.
In general, the impeller cup 101 and the blades 102 are integrally molded in one piece of a resin or the like. In this case, a stress is applied to an outer wall portion of the impeller cup 101 at the root portion 102a of each blade 102, at which the blade 102 comes in contact with the outer circumferential surface of the impeller cup 101. These stresses have certain distributions in circumferential and axial directions with respect to the outer wall portion of the impeller cup 101 depending on the arrangement of the root portions 102a of the blades 102. In the case where the number of blades 102 is large, the stress distributions are substantially even, whereas in the case where the number of blades 102 is small, the stress distributions are uneven. Therefore, when the number of blades 102 is small, the impeller cup 101 tends to undergo a deformation easily. The deformation of the impeller cup 101 will result in reduced adhesion between the impeller cup 101 and the rotor holder, which may lead to the impeller coming off the rotor holder. Moreover, in the case where there is only a small gap between the blades 102 and a case of the blower, the blades 102 may come in touch with the case during rotation of the impeller.
Furthermore, as the number of blades 102 decreases, the weight of each blade increases, and therefore the stress applied to the outer wall portion of the impeller cup 101 becomes greater. Thus, in the case where the number of blades 102 is small, the rotating impeller may undergo a deformation due to the stress, so that the impeller may come off the rotor holder or that the impeller cup 101 may be broken due to the stress. This problem becomes evident when the impeller is caused to rotate at a high speed in order to increase the air flow quantity of the blower.
It is conceivable to increase the wall thickness of the impeller cup 101 in order to overcome the above problem. However, it is difficult to simply increase the wall thickness thereof because of a deformation accompanying contraction when the impeller is molded of the resin, a constraint in terms of the outer diameter of the impeller cup 101, and so on.
It is also conceivable to increase the number of ribs provided on an inner circumferential surface of the impeller cup 101 to enhance the adhesion between the impeller cup 101 and the rotor holder. However, an increase in the number of ribs results in increased resistance when the rotor holder is press-fitted to the impeller cup, which may also lead to the breakage of the impeller cup 101.


A magnetic noise reducing device can effectively produce a practically noiseless space that can reduce environmental magnetic noise harmful for measuring biomagnetism with a high magnetism damping factor in low frequency range. The magnetic noise reducing device comprises a SQUID flux meter 1 and a pair of noise canceling coils 2 as minimum components, the feedback current I produced by the SQUID flux meter 1 being supplied to the noise canceling coils 2, the magnetic flux detecting coil of the SQUID flux meter being arranged within a specific central space 4 defined by the noise canceling coils 2 for effective reduction of magnetic noise within that space.

1. Field of Industrial Use
This invention relates to a magnetic noise reducing device for reducing the magnetic noise level and improving the S/N ratio in a setting for measuring the biomagnetism of a living body having a very low magnetic level in order to improve the reliability of the outcome of the measurement.
2. Prior Art
Reduction of the environmental magnetic noise level and improvement of S/N ratio is a serious concern in the measurement of the biomagnetism of a living body using a SQUID flux meter.
As illustrated in FIG. 2(A) of the accompanying drawings, the environmental magnetic noise is correlated with 1/f (f=frequency) in the low frequency range, showing a level between 1.times.10.sup.-10 and 1.times.10.sup.-9 T(Hz).sup.-1/2 for the frequency of 1 Hz and a higher level for lower frequencies. On the other hand, the level of the biomagnetism of a living body to be detected is found between 10.sup.-14 and 10.sup.-9 (depending on the intensity, the depth, the direction of emission of the signal generating source).
The frequency bandwidth (B) involved in the measurement of biomagnetism is normally around DC to 1 kHz. Since the noise level in a setting for measuring the biomagnetism of a living body is expressed by Bnx B.sup.1/2 (where Bn is magnetic noise per unit frequency), it will be approximately thirty two (32) times as large as that of 1.times.10.sup.-9 T(Hz).sup.-1/2 for DC to 1 kHz. Besides, the frequency characteristics of the noise involved need to be taken into consideration. If the noise level is of a magnitude of 5.times.10.sup.-9 T and a magnetic attenuation in the order of 10.sup.-14 is involved, the S/N ratio will be 1 for a signal of 10.sup.-14.
In view of the above facts, a magnetic noise reducing device is required to have a magnetism damping factor of 10.sup.5 to 10.sup.6 and be specifically effective for low frequency noises (less than 1 Hz) if it is effectively used for measuring biomagnetism.
Known means for reducing magnetic noise and means for canceling environmental magnetic noise include the followings.
a) magnetic shield room
This is a room constructed by using magnetically highly permeable materials such as Permalloy and providing magnetic noise damping areas inside the room.
FIG. 5 is a graph showing the frequency dependency of the magnetism damping factor of such a magnetic shield room. In FIG. 5, curves L.sub.1 and L.sub.2 show the magnetic damping factors of two magnetic shield rooms prepared by using walls having a multi-layered structure of aluminum and Permalloy plates. The magnetic damping factor of such a room is increased as the number of aluminum and Permalloy layers grows.
As is obvious from FIG. 5, such a magnetic shield room does not show a large magnetism damping factor for low frequency magnetic noise. Moreover, such a room inevitably provide only a narrow closed space for measurement and entails a high building cost of several hundred million yen.
b) electric method for canceling magnetic noise
This is a method using a device as illustrated in FIG. 6 to eliminate the noise component of output signal by determining the difference between the measurement of a signal detecting SQUID flux meter SC1 and that of a reference SQUID flux meter SC2. In FIG. 6, arrow M denotes signal, arrow N denotes noise, P1 and P2 denote controllers, Q and R respectively denote a signal processing circuit and the output terminal of the circuit.
Since such a device does not and cannot remove the magnetic field existing in the signal detecting space, corrective means may be additionally required for each of the channels involved if a multi-channel SQUID system is used.
c) gradiometer
As is known, a SQUID flux meter normally comprises a magnetic flux transformer constituted by a magnetic flux detecting coil MC, an input coil IP and a SQUID inductance SI as illustrated in FIG. 7. If the spatial gradient is known for the magnetic field to be detected, the gradiometer to be used for magnetic noise reduction are so designed that any magnetic fields having a gradient lower than it may be canceled.
If a magnet meter U, a primary differential gradiometer U1 and a secondary differential gradiometer U2 are arranged as illustrated in FIG. 8 to form a gradiometer for the purpose of magnetic noise reduction, such a gradiometer can selectively cancel even magnetic fields (primary differential) and/or magnetic fields up to the primary gradient (secondary differential) on site or produce .delta.Bz/.delta.x, .delta.Bz/.delta.y and/or .delta.Bx/.delta.z according to the purpose of measurement.
A gradiometer as described above is, however, accompanied by the disadvantage of a low sensitivity of a SQUID flux meter for magnetic flux density of higher orders, the sensitivity being remarkably lowered in terms of distance (in the Z direction for .delta.Bz/.delta.z) so that the canceling efficiency is determined by the winding balance, making the rate of noise reduction normally as poor as 10.sup.2 to 10.sup.4.
Contrary to the above described disadvantages of known magnetic noise reducing devices, a magnetic noise reducing device according to the invention is based on the principle of nil magnetic field detection that has been used for SQUID flux meters comprising a SQUID circuit having a feedback loop for making a SQUID element always show a nil magnetic field intensity. In other words, in a magnetic noise reducing device according to the invention, the feedback current of each SQUID flux meter it comprises is supplied not to a SQUID element but to corresponding noise canceling coils, the magnetic flux detecting coil of the SQUID flux meter being arranged within a given space defined by the surrounding noise canceling coils in order to operate the said magnetic flux detecting coil as a zero-level detecting coil so that said space defined by the noise canceling coils provides a space that can be effectively shut out magnetic noise.
More specifically, according to the present invention, there is provided a magnetic noise reducing device comprising an appropriate number of noise canceling coils and corresponding matching SQUID flux meters each having a magnetic flux detecting coil arranged within a specific space defined by the corresponding noise canceling coils, the output of each of said SQUID flux meter being supplied to said corresponding noise canceling coils as a feedback current.
Thus, with a magnetic noise reducing device according to the invention, a feedback current is supplied to a number of noise canceling coils not from an ordinary feedback circuit but from the corresponding SQUID flux meter.
Since the magnetic flux detecting coil of each of the SQUID flux meters is arranged within a magnetic space defined by the corresponding noise canceling coils, it operates as a nil detector. Thus, the noise canceling coils can provide a zero-magnetism space within a given space regarding the environmental magnetic noise.
Now, the present invention will be described in greater detail by referring to the accompanying drawings that illustrate preferred embodiments of the invention.

Active shielding device based on SQUID and feedback therefrom for the reduction of environmental magnetic noise


Leaves and other debris arranged in piles along a roadway are lifted by a flail-type rotary cutting device towed centrally behind a tractor. The device includes a containment hood having a forwardly opening throat which is adjustable to conform generally to the size of the piles for receiving the piles and restricting the material from being thrown forwardly from under the hood particularly at the end of a pile. The lifted material is delivered into a receptacle towed behind the cutting device. The rotary cutting device can handle leaves and other debris in states ranging from dry and fluffy to frozen and snow-covered. The tractor and/or additional brushes may be used for preliminary piles sizing and positioning. Brushes may also be added to the machine for additional cleaning action and to help part wide piles.

The present invention relates generally to street cleaning devices and, more specifically, to a device for picking up leaves and other debris from along streets and roads.
In many municipalities, leaf burning has been banned, and leaves must be collected by street crews in the fall. In a typical situation, property owners deposit leaves in large piles of varying sizes adjacent the street curb. Thereafter, the street crews use one of numerous methods to remove the leaves from the street. Present methods (including sweeping, vacuuming, baling, bagging and loading with front end loaders) are slow, expensive and labor and equipment intensive. Rain and snow present problems especially when attempts are made to vacuum wet material. At low temperatures, the vacuum tubes clog with ice because of the low pressure-high velocity air through the system. Baling and bagging require special handling, and, as with most common methods, large crews are necessary to keep up with the autumn disposal of leaves. Many of the presently used methods tend to block large areas of the roadway during the cleanup operation.

Street cleaning device for collecting leaves and debris


Described is a method for a coarse differentiation between a liquid and a bulk material of a filling material present in a receptacle using a filling level measuring device that scans a reflected echo signal. The coarse differentiation is made in dependence on the width of the individual echoes of an envelope curve in an echo signal. Alternatively, the coarse differentiation may also be made in dependence on the number of equidistant echoes in an echo signal, or in dependence on the detection of a stirring apparatus. All these alternatives may also be combined with each other. Also described are devices and filling level measuring devices configured for the realization of the methods.

The presence invention relates in general to a method for the automatic coarse differentiation between a liquid or a bulk material of a filling product present in a receptacle by analyzing an echo signal, in particular by analyzing the therefrom generated envelope curve of a filling level measuring device. The present invention further relates in general to devices for the automatic coarse differentiation between a liquid or a bulk material of a filling product present in a receptacle by analyzing an echo signal, in particular by analyzing the therefrom generated envelope curve, as well as filling level measuring devices working in particular on the pulse echo principle and scanning a reflected echo signal.
Filling level measuring devices working on the pulse echo principle and scanning a reflected echo signal, generate from the scanned echo signal a series of data for each echo in the echo image or the so-called envelope curve. Generating an envelope curve from echo signals is sufficiently known and, accordingly, further explanations as to this technology are not required here (cf., for example, German Patent DE 44 07 369 C2; M. Scholnik xe2x80x9cIntroduction to Radar Systemsxe2x80x9d, 2nd edition, 1980, McGraw-Hill; Peter Devine xe2x80x9cRadar level measurementxe2x80x94the user""s guidexe2x80x9d, VEGA Controls Ltd., 2000, ISBN 0-9538920-0-X).
Conventional filling level measuring devices or sensors detect the filling level by measuring individual echoes in the envelope curve. A method for the filling level measurement according to the radar principle is described in European Patent Application EP 1 039 273 A1, by means of which a non-planar, in particular arched bottom can be determined by examining the measurement signal or the envelope curve for a typical noise signal behavior. When this typical noise signal behavior is determined, the empty state of the receptacle is detected. A characteristic feature for the noise signal behavior of the measurement signal consists in erratic random changes of the local peaks or in an increasing amplitude of the local minimum or maximum points with a rising frequency. German Patent DE 43 32 071 A1 described a method for the filling level measurement according to the radar principle is known, wherein the actual echo function is compared to memorized undisturbed echo function, which corresponds to an undisturbed measurement, and deviations ascertained in the antenna zone and the short range following the antenna, are evaluated for recognizing an initial formation and/or other disturbances. Furthermore, Great Britain Patent Application GB 2 123 237 A shows a filling level detector working with microwaves, which does not work according to the echo principle, but causes the reflected beam to interfere with a beam branched off using a waveguide.
With the conventional devices, it is, however, necessary for improving the evaluation of the envelope curve, to manually input whether the filling product to be measured is a liquid or a bulk material. Through this manual input, the type of the envelope curve measurement, and hence the determination of the filling level, is changed. Thus, if it is predetermined that the filling product is a liquid, the amplitude to be measured is placed at a predetermined amplitude before the maximum of the envelope curve with prior art. In case the operator has predetermined that the filling product is a bulk material, the beginning of the envelope curve up to the maximum is measured as the amplitude to be measured.
In summary, it has to be stated that according to prior art, an improved measurement of the individual echoes of an envelope curve of an echo signal depending on the type of filling product, is only then possible when a coarse manual differentiation on the filling level measuring device is carried out by an operator.
The present invention relates to a method and a device for carrying out an automatic coarse differentiation between a liquid or a bulk material of a filling product present in a receptacle. A possibility is therewith supposed to be created that a filling level measuring device working in particular on the pulse echo principle and scanning a reflected echo signal, automatically carries out a coarse differentiation between a liquid or a bulk material of the filling product.
In particular, according to a first exemplary embodiment of the present invention, a method for the coarse differentiation between a liquid and a bulk material of a filling product present in a receptacle is described, where a filling level measuring device is used scanning a reflected echo signal, and the coarse differentiation is made in dependence on the width of the individual echoes of an envelope curve in an echo signal.
According to a further exemplary embodiment of the present invention, a method for the coarse differentiation between a liquid and a bulk material of a filling product present in a receptacle using a filling level measuring device scanning an echo signal is described, where the coarse differentiation is made in dependence on the number of equidistant echoes in an echo signal.
According to yet another exemplary embodiment of the present invention, a method for the coarse differentiation between a liquid and a bulk material of a filling product present in a receptacle, using a filling level measuring device scanning an echo signal, is described, where the coarse differentiation is made in dependence on the detection of a stirring apparatus.
A preferred exemplary embodiment of a device according to the present invention for the coarse differentiation between a liquid and a bulk material of a filling product present in a receptacle, includes an arrangement for detecting the echo widths of echoes of a generated envelope curve, an arrangement for detecting the number of echoes having an echo width larger than a reference echo width, and the number of echoes having an echo width smaller than the reference echo width, and a signal outputting arrangement for the type of filling product, which signal outputting arrangement outputs a signal representative of a liquid when the number of echoes having an echo width larger than a reference echo width is greater than the number of echoes having an echo width smaller than a reference echo width.
A further preferred exemplary embodiment of a device according to the present invention for the coarse differentiation between a liquid and a bulk material of a filling product present in a receptacle, includes an arrangement for determining the number of equidistant echoes of a generated envelope curve, and an arrangement for outputting a signal determining the type of filling product in dependence on the determined number of equidistant echoes.
Still another preferred exemplary embodiment of a device according to the present invention for the coarse differentiation between a liquid and a bulk material of a filling product present in a receptacle, includes an arrangement for detecting a stirring apparatus by evaluating the echoes of a generated envelope curve, and an arrangement for outputting a signal representative of the type of filling product in dependence on the detection of a stirring apparatus.
Furthermore, according to yet another exemplary embodiment of the present invention, a filling level measuring device is described. The filling level measuring device utilizes a pulse echo principle which evaluates an envelope curve generated from the reflected echo signal, and including a device according to the above configurations. The device may also be modified according to one or more of the following configurations.
As indicated above, the present invention utilizes an idea of examining for the first time the individual echoes of an envelope curve for determined characteristics providing at least an indication as to the type of the filling product, namely liquid or bulk material. Thus, it is possible to make this coarse differentiation in dependence on the width of the individual signals of an envelope curve in an echo signal. Profit is thereby taken from the fact that, caused by the shape of a bulk material, wide echoes are more likely to occur in a product. When the filling product is a liquid, narrow echoes are more likely to occur in the envelope curve. By therewith relating the echo width of all echoes within an echo curve, or the echo image, to a predetermined reference echo width value, which is easy to fix by simple tests, then it can be concluded, if it is stated that the number of the wide echoes is larger than the number of the narrow echoes, that the filling product in question is a bulk material. Otherwise, it would be a liquid. Under circumstances, it is also purposeful to indicate that a mixture of these two basic types of filling products is concerned.
As an alternative hereto, it is yet also possible to examine the envelope curve for the fact how the distance between the individual echoes to be detected is relative to each other. Here, profit is taken from the effect that in case the filling product in question is a liquid, the echoes are more likely to occur at regular distances relative to each other. Hence, if it is stated that the echoes are present in the echo signal at regular distances, then it is possible to draw conclusions as to the type of the filling product. As an example, the case shall be mentioned that more than three equidistant echoes are detected. In this case, it is outputted that the filling product in question is a liquid.
A further alternative could consist in carrying out the coarse differentiation in dependence on the detection of a stirring apparatus. If a stirrer is recognized in the echo signal, then it may be concluded that the filling product concerned is a liquid.
It is of course also possible to combine one or more of the aforementioned alternatives for the coarse differentiation between a liquid or bulk material of the filling product, so as to increase the safety of recognizing the type of filling product. Further, it is of course also possible to lend weight to these separate alternatives with respect to each other, when they are combined, that is, to multiply them in each case with a predetermined (under circumstances even variable) factor. As a matter of course, these factors may be identical for any of the type of coarse differentiation described above, or may even be different. Through the corresponding weighting, the one or the other presented type of coarse differentiation may be imparted more or less weight.
The type of the coarse differentiation in dependence on the width of the individual echoes of an envelope curve can in particular be met in that the number of the echoes having a width larger than a reference echo width, and the number of the echoes having a width smaller than the reference echo width is ascertained. For the coarse differentiation, the ascertained larger echo number will then be referred to. Thus, as an example shall be mentioned here that in an envelope curve, four echoes are ascertained, which are larger than a reference echo width, and two echoes, which are smaller than the reference echo width. Then the coarse differentiation is made in that a bulk material is presumably concerned, since it is rather characteristic for a bulk material that the width of the echoes is larger than with a liquid.
An advantageous embodiment of this method hence provides that after the detection of the individual signals in the echo signal, the widths of individual echoes in an echo signal of an envelope curve are then ascertained by conventional (mathematical) means. Thereupon, the number of the echoes having a width greater than or equal to a reference echo width is ascertained. The number of the echoes having a width smaller than a reference echo width is likewise assessed. Thereupon, a signal determining the type of filling product is outputted in dependence on the echo widths, the number of which has been ascertained to be larger.
With the alternative for the coarse differentiation between bulk material or liquid of the filling product, wherein the equidistant echoes are ascertained in an echo signal, the distance between adjacent echoes in an envelope curve are in each case measured. Then, all echoes are preferably summarized which exhibit a distance relative to each other falling into a predetermined tolerance band (i.e. a distance range), hence equidistant echoes. The distance of the echoes is preferably calculated so that the respective locations of the maximum points of the individual echoes are determined, and the distance between these maximum points is measured. The tolerance band can be a fixed value range, e.g. xc2x10.1 m. It is in particular advantageous to take the first distance between the zero point and the first echo as the reference distance. In this case, it is for example advantageous to fix the tolerance range at xc2x150 cm, i.e. that all those echoes are considered to be equidistant echoes, the distance from each other is equal to the reference distance of xc2x150 cm. If another echo distance is fixed as the reference distance, then the tolerance band preferably has to be set to be smaller than xc2x150 cm.
In the further alternative for the coarse differentiation made with consideration of the ascertainment of a stirrer, echoes of an actual envelope curve are preferably compared with the corresponding echoes of the preceding envelope curve. Echoes from running stirrers are characterized in that their amplitude highly fluctuates, or that echoes having a large signal noise distance, i.e. the amplitude of the echo above the system noise or the dying-out transmission signal, periodically disappear and reappear. Such echoes can be marked and excluded from the filling level decision. In the present case, they are preferably used for a stirrer recognition and for accordingly outputting that the filling product in question is a liquid. Two envelope curves are in particular compared for determining the amplitude fluctuation of individual echoes, and the amplitude fluctuation thereof is compared to a reference value.
As explained above, the separate types of coarse differentiation as described before may be used individually or may be arbitrarily combined with each other. In this case, it is advantageous that the information of each type of filling product coarse differentiation is multiplied by a weighting factor, and the therefrom resulting values are added and divided by the sum of the weighting factors so as to ascertain a probability whether a liquid or a bulk material is concerned. In particular, it is then advantageous that the therefrom resulting value is compared to a reference value. If the ascertained value is, for example, smaller than this reference value, then a signal has to be outputted which is representative of liquid. In the other case, a signal has to be outputted which is representative of bulk material.
A corresponding device for the differentiation between a liquid or a bulk material of a filling product present in a receptacle, includes in an embodiment an arrangement for detecting the echo widths of echoes of a generated envelope curve, an arrangement for detecting the number of echoes having a width greater than a reference echo width, and the number of echoes having an echo width smaller than the reference echo width. Further, a signal outputting arrangement for the type of filling product is present, which outputs a signal representative of a liquid, when the number of echoes having an echo width larger than a reference echo width is greater than the number of echoes having an echo width smaller than a reference echo width.
An alternative exemplary embodiment according to the present invention includes an arrangement for detecting the number of equidistant echoes of a generated envelope curve, and an arrangement for outputting a signal determining the type of filling product in dependence on the detected number of equidistant echoes.
A further alternative exemplary embodiment of a device for the coarse differentiation between a liquid and a bulk material of a filling product present in a receptacle, is equipped with an arrangement for detecting a stirring apparatus by evaluating the echoes of a generated envelope curve, and an arrangement for outputting a signal representative of the type of filling product in dependence on the detection of a stirring apparatus.
A further preferred exemplary embodiment of the present invention may include one or more of the aforementioned arrangements, so that the different types of coarse differentiation are combined with each other. The individual arrangement work according to the above-described methods.
Finally, it has to be noted that the aforementioned methods can, for example, be implemented in an evaluation program for evaluating generated envelope curves.
Such evaluation programs are, for example, known under the trademark Echofox(copyright) of the company VEGA Grieshaber KG, Germany. Accordingly, methods and devices according to the present invention, or the correspondingly functioning software, can either be implemented in separate evaluation arrangement or, if desired, can be directly integrated in filling level measuring devices. Filling level measuring devices of the type interesting here, for the remainder, are all known filling level measuring devices, which scan a reflected echo signal, i.e. which generate en envelope curve. Such filling level measuring devices are, for example, ultrasonic filling level measuring devices or radar filling level measuring devices, in particular, so-called pulse radar filling level measuring devices.

Method and device for the coarse differentiation between a liquid or a bulk material of a filling product present in a receptacle