We describe an example system that includes a plurality of aggregation nodes. Each aggregation node is configured to generate a node utilization data. A pool master is configured to generate a node utilization list responsive to the node utilization data received from each aggregation node and to activate the plurality of aggregation nodes responsive to the node utilization list.

An aggregation node, e.g., a broadband remote access server (BRAS), routes traffic to and from a subscriber on an Internet service provider's (ISP's) network. The aggregation node sits at the core of an ISP's network, aggregates user sessions from the access network, and routes traffic into the ISP's backbone network. An ISP may also inject policy management and Quality of Service (QoS) in the network through the aggregation nodes.
A network may include a plurality of aggregation nodes. A subscriber may connect to the network and the plurality of aggregation nodes through a digital subscriber line access multiplexer (DSLAM). In a broadband aggregation network, a subscriber usually connects to a single aggregation node that may, in turn, connect to other such subscribers. Each of the subscribers connected to the single aggregation node may require different bandwidth or load. The aggregation node, therefore, must be adequately sized to support the highest subscriber bandwidth or load requirement resulting in misuse of aggregation node resources. And the single aggregation node catering to a plurality of subscribers may not scale well and provide a single failure point. No mechanism currently exists to balance subscriber loads across a single or multiple aggregation nodes in a fair and balanced manner. The standard mechanisms used for aggregation, e.g., point-to-point protocol (PPP) and dynamic host configuration protocol (DHCP), rely on a first-response from the aggregation node and have no inherent load balancing capabilities.

Load balancing of broadband subscriber sessions


A method for forming an isolation layer for a semiconductor device is provided. The preferred method is capable of securing a gap fill margin during formation of an isolation layer. A device isolation layer formed according to a preferred method includes a trench formed in a device separation area of a semiconductor substrate; a thermal oxidation layer formed in a part of the trench; an oxidation silicon layer formed on the thermal oxidation layer; and an oxidation isolation layer formed on the oxidation silicon layer and filling the trench.

In general, semiconductor devices include a device isolation area for electrically separating respective circuit patterns and a device formation area for forming respective circuit patterns.
According to the recent high integration of semiconductor devices, methods for reducing a device isolation area and a device formation area are being suggested.
The most common method for forming the device isolation area is STI (Shallow Trench Isolation).
Hereinafter, a method for forming an isolation layer in a semiconductor device according to the related art will be described with reference to the accompanying drawings.
FIGS. 1a through FIG. 1d are cross-sectional views for illustrating a method for forming an isolation layer in accordance with the related art.
Referring to FIG. 1a, an oxide layer 102 and a nitride layer 103 are deposited on a semiconductor substrate 101.
A photosensitive resist is coated on a top surface of the nitride layer 103 and patterned by an exposure and developing process to form a photoresist layer pattern 104 exposing the nitride layer 103 on an isolation region.
Referring to FIG. 1b, a trench 105 having a predetermined depth is formed by performing an etching process using the photoresist layer pattern 104.
The photoresist layer pattern 104 is removed through a cleaning process, and a thermal oxidation layer 106 is formed in the trench 105 by a thermal oxidation process.
Then an isolation bed 107a is formed by performing a gap fill (isolation material) process on the substrate including the thermal oxidation layer 106 in the trench 105.
Material used for forming the isolation layer 107a is a high density plasma oxide.
Referring to FIG. 1c, a planarization process is performed on the surface of the semiconductor substrate 101 until the nitride layer 103 is exposed to form the isolation layer 107 from the isolation bed 107a.
Herein, the semiconductor substrate 101 is planarized through CMP (Chemical Mechanical Polishing) process, and the isolation layer 107 is formed inside of the trench 105.
Referring to FIG. 1d, the oxide layer 102 and the nitride layer 103 are removed by a wet etching and cleaning process.
Accordingly, a device isolation layer is formed in the device isolation area by the isolation material filled in the trench 105.
However, as semiconductors become smaller and highly integrated, the isolation layers become deeper and more narrow.
Therefore, it becomes more and more difficult to completely fill isolation material in a trench that is formed deep and narrow due to the increasingly high level of integration of devices.
Accordingly, the conventional chemical deposition method may not be capable of securing the gap fill margin of isolation material filled in a deep and narrow trench.

Method for forming isolation layer in semiconductor devices


Disclosed is an apparatus and a method for controlling a user interface having a touch screen which includes an input and output unit having a touch screen, a camera which is installed to be separated from the input and output unit, and obtains at least one of an image data corresponding to a space within a critical distance from a front of the touch screen, and a controller which verifies an expected touch position of an object when a movement of the object is detected in the space as a result of an analysis of the image data, and controls the input and output unit to enlarge and output an area corresponding to the expected touch position.

1. Technical Field
The present disclosure relates to an apparatus and a method for controlling a user interface having a touch screen, more particularly, to an apparatus and a method for controlling a user interface having a touch screen which verifies an area where a touch will be generated prior to a generation of a touch on a touch screen by equipping a depth recognition camera, and enlarging and outputting the verified area to a screen.
2. Description of the Related Art
In general, a text input method of a portable terminal using a touch screen includes a handwriting recognition method and a virtual keyboard input method. The handwriting recognition method is a method converting into a data code after recognizing a handwriting of a person by a touch screen, and the virtual keyboard input method is a method receiving a selection information according to a touch of a touch tool capable of using a touch such as a finger or a pen by pop up an input window of a keyboard type on the touch screen to overcome a transportability problem of a keyboard and a mouse in the portable device.
Examples of a terminal equipping with such a touch screen includes an electronic notebook, a mobile communication terminal, a Personal Digital Assistant (PDA), a portable multimedia player (PMP), and a navigation device.
However, in case of the virtual keyboard input method, since it has to display a text input window and the virtual keyboard on a screen at the same time, a size of a key of the virtual keyboard is small. Due to this, it has a problem of causing a typing error frequently by touching a neighboring key in a procedure of touching the key on the virtual keyboard. In particular, when selecting a key with a touch tool having a spacious touch area, or when the virtual keyboard is displayed on a small screen, the input error corresponding to the touch error occurs frequently.
In addition, when a navigation device is equipped with the touch screen, since a driver frequently operates the navigation device during the driving, it may lower the driver's concentration and lead to causing an accident.

Apparatus and method for controlling of user interface equipped touch screen


Core support blockings (10, 12) used to support a toroidal transformer (2) within a transformer housing (4) includes a pie-shaped body (28) having a second end (32) secured to the transformer core (14) using an adhesive (41). The body has adhesive flow regions, typically countersunk holes (42) passing through mounting flanges (38, 40) extending laterally adjacent the second end of the body. Electrical windings (26) can be wound on first end of the mounting flanges so to help mechanically secure the body to the core. A mounting stud (46), or other mounting element, is used to secure the transformer to a support bracket (8). Together the support bracket and core support blockings are used to support the transformer within the transformer housing.

Toroidal transformer assemblies include, broadly, a transformer, a transformer container or housing and mounting hardware for supporting the transformer within the housing. The transformer includes a cylindrical core, made of magnetic steel, and various electrical coils wound around the core and passing through the eye of the core.
Electrical toroidal distribution transformers, typically having ratings of 10 to 50 Kva, are relatively large and quite heavy, weighing from about 40 kg. for 10 Kva transformers to about 100 kg. for 50 Kva transformers. Also, distribution transformers create heat and a certain amount of vibration during use and must withstand movement during handling and installation. Such transformers thus require sturdy mounting hardware. However, the mounting hardware should not be such to affect the electrical, magnetic or thermal performance of the transformer.
Another problem associated with the manufacture of distribution-type electrical transformers relates to size variation. First, different size transformers with their different Kva and voltage ratings must be accommodated, often using the same size transformer housing. Second, due to core variations and the necessarily imperfect windings associated with toroidal transformers, the dimensions of transformers having the same nominal rating will vary somewhat.
One type of transformer mounting hardware is shown in U.S. Pat. No. 4,833,436 for Formed Metal Core Blocking, issued May 23, 1989, the disclosure of which is incorporated by reference. It uses U-shaped steel stampings which generally circumscribe the core and also extend into the interior of the core. This design, while effective at supporting the transformer, is not very adaptable to transformers having different inside and outside diameters. Also, the presence of support structure within the eye of the transformer hinders the flow of cooling fluid through the core.

Core support blocking for toroidal transformers


The application discloses novel polymorphic crystalline forms of 2-[4-Bromo-3-(3-chloro-5-cyano-phenoxy)-2-fluoro-phenyl]-N-(2-chloro-4-propionylsulfamoyl-phenyl)-acetamide, sodium salt (Ib)

The human immunodeficiency virus HIV is the causative agent of acquired immunodeficiency syndrome (AIDS), a disease characterized by the destruction of the immune system, particularly of the CD4+ T-cell, with attendant susceptibility to opportunistic infections. HIV infection is also associated with a precursor AIDs-related complex (ARC), a syndrome characterized by symptoms such as persistent generalized lymphadenopathy, fever and weight loss.
In common with other retroviruses, the HIV genome encodes protein precursors known as gag and gag-pol which are processed by the viral protease to afford the protease, reverse transcriptase (RT), endonuclease/integrase and mature structural proteins of the virus core. Interruption of this processing prevents the production of normally infectious virus. Considerable efforts have been directed towards the control of HIV by inhibition of virally encoded enzymes.
Currently available chemotherapy targets two crucial viral enzymes: HIV protease and HIV reverse transcriptase. (J. S. G. Montaner et al. Antiretroviral therapy: 'the state of the art', Biomed & Pharmacother. 1999 53:63-72; R. W. Shafer and D. A. Vuitton, Highly active retroviral therapy (HAART) for the treatment of infection with human immunodeficiency virus type, Biomed. & Pharmacother. 1999 53 :73-86; E. De Clercq, New Developments in Anti-HIV Chemotherap. Curr. Med. Chem. 2001 8:1543-1572). Two general classes of RTI inhibitors have been identified: nucleoside reverse transcriptase inhibitors (NRTI) and non-nucleoside reverse transcriptase inhibitors.
NRTIs typically are 2′,3′-dideoxynucleoside (ddN) analogs which must be phosphorylated prior to interacting with viral RT. The corresponding triphosphates function as competitive inhibitors or alternative substrates for viral RT. After incorporation into nucleic acids the nucleoside analogs terminate the chain elongation process. HIV reverse transcriptase has DNA editing capabilities which enable resistant strains to overcome the blockade by cleaving the nucleoside analog and continuing the elongation. Currently clinically used NRTIs include zidovudine (AZT), didanosine (ddI), zalcitabine (ddC), stavudine (d4T), lamivudine (3TC) and tenofovir (PMPA).
NNRTIs were first discovered in 1989. NNRTI are allosteric inhibitors which bind reversibly at a nonsubstrate-binding site on the HIV reverse transcriptase thereby altering the shape of the active site or blocking polymerase activity (R. W. Buckheit, Jr., Non-nucleoside reverse transcriptase inhibitors: perspectives for novel therapeutic compounds and strategies for treatment of HIV infection, Expert Opin. Investig. Drugs 200110(8)1423-1442; E. De Clercq The role of non-nucleoside reverse transcriptase inhibitors (NNRTIs) in the therapy of HIV infection, Antiviral Res. 1998 38:153-179; E. De Clercq New Developments in Anti-HIV Chemotherapy, Current medicinal Chem. 2001 8(13):1543-1572; G. Moyle, The Emerging Roles of Non-Nucleoside Reverse Transcriptase Inhibitors in Antiviral Therapy, Drugs 2001 61 (1):19-26). Although over thirty structural classes of NNRTIs have been identified in the laboratory, only three compounds have been approved for HIV therapy: efavirenz, nevirapine and delavirdine.
Initially viewed as a promising class of compounds, in vitro and in vivo studies quickly revealed the NNRTIs presented a low barrier to the emergence of drug resistant HIV strains and class-specific toxicity. Drug resistance frequently develops with only a single point mutation in the RT. While combination therapy with NRTIs, PIs and NNRTIs has, in many cases, dramatically lowered viral loads and slowed disease progression, significant therapeutic problems remain. (R. M. Gulick, Eur. Soc. Clin. Microbiol. and Inf. Dis. 2003 9(3):186-193) The cocktails are not effective in all patients, potentially severe adverse reactions often occur and the rapidly reproducing HIV virus has proven adroit at creating mutant drug-resistant variants of wild type protease and reverse transcriptase. There remains a need for safer drugs with activity against wild type and commonly occurring resistant strains of HIV.
2-[4-Bromo-3-(3-chloro-5-cyano-phenoxy)-2-fluoro-phenyl]-N-(2-chloro-4-propionylsulfamoyl-phenyl)-acetamide, sodium salt, the compound of formula Ib
was disclosed, as well as its method of preparation, and its activity as an inhibitor of HIV Reverse Transcriptase in U.S. Pat. No. 7,166,738, which is herein incorporated by reference in its entirety.
Salts of acidic and basic compounds can alter or improve the physical properties of a parent compound. These salt forming agents, however, must be identified empirically by the pharmaceutical chemist since there is no reliable method to predict the influence of a salt species on the behavior of a parent compound in dosage forms.
Polymorphism is the ability of any element or compound to crystallize as more than one distinct crystalline species. Different polymorphic forms of salts are frequently encountered among pharmaceutically useful compounds. Physical properties including solubility, melting point, density, hardness, crystalline shape and stability can be quite different for different polymorphic forms of the same chemical compound.
Polymorphic forms are characterized by scattering techniques, e.g., x-ray diffraction powder pattern, by spectroscopic methods, e.g., infa-red, 13C nuclear magnetic resonance spectroscopy and by thermal techniques, e.g, differential scanning calorimetry or differential thermal analysis. Polymorphs are best characterized by the X-ray powder diffraction pattern determined in accordance with procedures which are known in the art. For a discussion of these techniques see J. Haleblian, J. Pharm. Sci. 1975 64:1269-1288, and J. Haleblain and W. McCrone, J. Pharm. Sci. 1969 58:911-929. Although the intensities of peaks in the x-ray powder diffraction patterns of different batches of a polymorph may vary slightly, the peaks and their relative peak positions are characteristic for a specific polymorphic form.
The problem which must be solved is to identify a suitable salt and/or polymorph which (i) possesses adequate physical and chemical stability during the manufacturing process, (ii) is efficiently prepared, purified and recovered, (ii) provides acceptable solubility in pharmaceutically acceptable solvents, (iii) is amenable to manipulation (e.g. flowability and particle size) and formulation with negligible decomposition or change of the physical and chemical characteristics of the compound, (iv) exhibits acceptable physical and chemical stability in the formulation. In addition, salts which contribute minimally to the molar weight so that the resulting material comprises a high molar percent of the active ingredient are highly desirable since the quantity of material which must be formulated and administered to produce a therapeutically effective dose is minimized. These oft conflicting requirements make identification suitable salts a challenging and important problem which must be solved by the skilled pharmaceutical scientist before drug development can proceed in earnest.

Abstract: with improved stability and physical properties which facilitate manufacturing, handling and formulating for treatment or prophylaxis of HIV mediated diseases, AIDS or ARC, in monotherapy or in combination therapy.


A method and an x-ray apparatus produces a standard set of x-rays of a person's head while he or she is in a prone position. A movable frame is rigidly connected to a table, such as an operating table, and an extendible arm having a receiver for an x-ray source at a distal end provides for placement of the x-ray source in various, fixed positions. Right and left lateral cephalograms, an anterior-to-posterior cephalogram, and right and left transcranial views of the temporomandibular joint are provided by the fixed-position x-ray source. A panorama x-ray machine is also movably engaged with the frame for taking panographic images. A first set of cephalograms can be taken of a patient on an operating table, and the portable x-ray apparatus can be moved away from the operating table. A surgical treatment objective can be overlaid on the first set of cephalograms. Oral or orthognathic surgery or repair can be performed, and the portable x-ray apparatus can be subsequently reconnected to the operating table for taking a second set of cephalograms that precisely overlay the first set. A surgical team can thus compare actual operative results with the surgical treatment objective, and if necessary, make changes while the patient is still on the operating table.

1. Field of the Invention
This invention pertains to a method and an apparatus for taking x-rays and more particularly to a method and an apparatus for providing a reproducible set of x-rays of a patient in a prone position.
2. Description of the Related Art
A set of x-rays is taken before orthognathic surgery, which is surgery to reposition the bones of the face and jaw. A surgical treatment objective is developed and traced onto x-ray films to provide a plan for movement of hard tissues in and around a person's jaw. A second set of x-rays is taken after the surgery, but typically a couple of days after the surgery, when the patient is able to stand or sit for orthodontic x-rays. The post-surgery x-rays are compared to the surgical treatment objective to determine whether the desired results were achieved. If the desired results were not achieved, then the patient must be operated on a second time, leading to the additional risk, discomfort and expense of a second surgical procedure. Even a very small deviation between a desired result and an actual result can be unacceptable because misalignment of a person's jawbone can result in poor cosmetic and functional result and temporomandibular joint pain.
The need for orthognathic surgery typically arises as a procedure for correcting an improper location of jawbones or teeth. Victims of trauma to the face, such as victims of car accidents and gun shot wounds, also have a need for pre-surgery and post-surgery x-rays of the jawbones and teeth. Trauma victims and other persons, such as invalids, are frequently unable to stand or sit while a set of orthodontic x-rays are taken. It is thus necessary to take the x-ray while the person is in a prone position, such as on an operating table. However, x-rays currently taken of a patient in a prone position differ in magnification and orientation from one set of images to a second set of images taken subsequent in time.
In U.S. Pat. Nos. 4,566,444; 4,579,117; and 4,683,582, issued to Spolyar, a portable cephalostat is disclosed as having a frame-like base sub-assembly that provides an area upon which a patient's head can rest. The base sub-assembly provides a support for supporting locating arms that serve to locate the patient's head in a selected position. An x-ray film is secured to the base sub-assembly in various positions, one below the patient's head and others on each side of the head generally parallel to a mid-sagittal plane of the patient's head. Spolyar provides a telescoping rod, resembling an antennae, as an indicator of a desired location for an anode of an x-ray machine. Spolyar also discloses calculations for determining a degree of magnification on an x-ray film, which is related to distances between the film and the patient and the patient and the anode of the x-ray machine. There is no rigid capture of the patient's head relative to an x-ray source. X-ray films taken subsequent in time are not sufficiently identical to x-rays taken earlier in time. The level of precision is inadequate.
U.S. Pat. No. 5,148,454, issued to Coffman, discloses an apparatus for conducting cranial x-ray tomography and radiography. An apparatus is disclosed having a horizontally oriented, motor driven rotatable shaft for imparting controlled rotation to an elongate support member having an x-ray source and a film holder provided at an opposite end. The apparatus includes a cephalometer that supports a patient's head at a fixed position during x-ray tomography and radiography procedures. However, the apparatus is not portable and is not suitable for taking x-rays of a patient in a prone position.
U.S. Pat. No. 4,831,645, issued to Guenther et al., discloses an apparatus for positioning the head of a patient for producing dental panorama tomograms. The apparatus has an arrangement for positioning the head in a desired position relative to a fixed point with respect to at least one projection plane. This point in turn assumes a definite position relative to a central ray extending from an x-ray tube towards an x-ray picture. A silhouette of the head is produced and projected, and an actual position is compared to a desired position. The head is moved until the silhouette of the actual position is congruent with the silhouette of the desired position, which brings the head into the desired position for x-ray exposure.
U.S. Pat. No. 4,759,361, issued to Gallop et al., discloses a telescoping adjustment assembly for a head positioner used in a cephalostat. A cephalostat housing has a pair of ear posts carried outwardly of the cephalostat housing and moveable toward the cephalostat housing so that the mid-sagittal of the head may be repetitively positioned in a same alignment to obtain a consistent series of radiographs over time. A patient's dentition and temporomandibular joint can be located in virtually the same arrangement relative to the film for x-rays taken at different times, such as for determining a patient's progress during orthodontia. However, the apparatus has a wall plate support for attachment to a wall and is thus not portable or suitable for use in an operating room.
U.S. Pat. No. 4,783,793, issued to Virtia et al., discloses a panoramic tomography x-ray apparatus such as for obtaining images of dental systems. An x-ray tube of an x-ray generator and an x-ray film cartridge are mounted to an arm that is rotatable. A control system for controlling the functioning of the equipment and apparatus on the basis of control data and a pre-stored program are disclosed. The control system controls the speed of a rotary motion motor that rotates the arm, the speed of the film transport motor and the distribution of those speeds, independently of each other. However, the apparatus is not adapted for use in an operating room on a patient in a prone position.


An exercise device includes a first frame member spaced apart and parallel to a second frame member. Each frame member has equi-length right and left straight sections connected by a central arcuate section such that in the upright position the first and second frame members are each inverted V shapes. Four spaced apart transversely oriented cross members namely grips, are configured to rigidly connect together the first and second frame members. The grips each include grip apertures for attaching to the grips longitudinally oriented a right inner handle bar and a left inner handle bar to the inner right and left grips and right outer handle bar and left outer handle bar to the right and left outer grips, each handle bar is a cylindrically shaped rod and is configured for grasping with a hand and for slide-ably receiving free weight plates thereon.

There is a tremendous amount of information in the literature regarding the benefits of physical activities including the benefits of increasing physical strength through weightlifting activities. Many exercises can be performed which usually require weights or other forms of resistance. The equipment used in these exercises are normally found in public and private gyms or in some cases purchased by individuals for use in their home. In many cases, this equipment is relatively expensive and a large amount of storage space is needed for the devices.
There are many different types of exercises that can be performed using free weights. For example, linear barbells are often used for straight lifts, curls, and triceps lifts. In addition to these traditional lifts users of free weights also like to carry out close grip barbell triceps press exercises, hammer grip over head dumbbell shoulder press exercises and reverse grip bent over barbell row exercises.
There is a need for a device which enables a multitude of different free weight exercises to be carried out, some of which have been mentioned above, in addition to other exercises such as a close grip push ups and a wide grip push ups and various other exercises. Therefore there is a need for a free weight lifting device which provides for the greatest range in regards to the number of exercises that can be carried out with the device and yet have a device which is inexpensive and as compact as possible so as to take up very little space for the home user.


A system, an apparatus and a method for automatically controlling application of an agricultural product utilize an in-cab controller and touchscreen, and a GPS receiver to generate an application prescription and related commands on-the-fly from GPS coordinated data gathered at the time of planting, in accordance with application rate parameters stored in the controller. The application parameters may be provided and modified on-the fly using the touchscreen and may include parameters relating to adjusting application rates to accommodate planting arrangements including more than one variety of seed, and/or variable population rates of planted seed.

Modern agricultural practices rely on timely and accurate applications of agricultural products, such as fertilizer, insecticide, fungicide, weed control agents, and the like.
In the past, crops were planted in an essentially uniform manner, using only one variety of seed, across a given field. An application rate for a subsequently applied agricultural product was selected and applied uniformly to the entire field. Typically, the application rate was entered manually into a control unit adapted for controlling the applicator as the applicator was subsequently moved across the field by a propulsion vehicle.
Alternatively, a so called "prescription" for uniform application of the agricultural product at a fixed rate across the field was worked out in advance, using GPS coordinated planting data recorded at the time of planting the crop in the field and soil test data. The prescription was then provided as a data input to the applicator control unit, or it was manually entered into the applicator controller by an operator prior to beginning application of the agricultural product.
With these and other prior approaches, once the uniform, fixed application rate was entered into the applicator controller options for modifying during application of the product were limited. Operators typically had some ability to manually modify the application rate as the applicator moved across the field, to fine-tune the fixed application rate, but such manual alterations typically affected the entire swath of the field to which the agricultural product was presently being applied by the applicator. The application rate typically then stayed at the modified rate for the remainder of the application operation, unless the operator again manually modified the application rate.
Such prior practices generally provided satisfactory results for a single variety of seed planted uniformly across the field, but they were wasteful in that the uniform application rates resulted in wasteful overapplication of the agricultural product in some areas of the field, and potential loss of yield due to underapplication of the agricultural product in other areas of the field. Such prior practices also required a substantial input of operator energy and skill, particularly where continual manual modifications were used to tailor the application rate to better match actual field and crop conditions.
Today, modern planting equipment is capable of varying a number of parameters, such as planting population or spacing, and changing between multiple varieties across a given area of a field or even in the same row, to improve yield and profitability by optimizing the placement of seed to match soil fertility and other factors. Modern planting equipment has the capacity to record GPS cross-referenced data relating to the placement and spacing of seeds and varieties planted, as the crop is planted. Gaps in rows or areas of the planting area are also typically recorded.
These additional capabilities of planting equipment have substantially increased the number of variables involved in the application of agricultural products subsequent to planting, and also provide a wider variety of potential options for tailoring application of the placement and application rate of the agricultural products across the field. Prior approaches to making manual adjustments cannot realistically be used to adjust for all of these additional variables and take advantage of such a wide range of potential options for more effectively and efficiently placing the agricultural product where it will result in optimal crop production in the field.
Although some of these additional variables and options could conceivably be factored into a more complex prescription prior to heading for the field to apply the agricultural product, such complex pre-application preparation of a prescription for a field is time consuming and limited by the assumption that the actual conditions of the crop in the field are as intended at the time of planting. Such complex pre-application prescriptions are also prepared using average, or standardized application rate data for the agricultural product to be applied, and they may not be tailored to the particular operating parameters of the application equipment available for use when the product needs to be applied for optimal effect.
Subsequent to planting, development of wet areas due to rainfall, flooding, or drainage tile problems may have affected the actual standing crop. Other factors such as unusually high or low insect or weed infestations, or problems with unanticipated plant diseases, defective seed, or problems with planting equipment cannot always be accounted for in pre-prepared prescriptions, and they may not be recognized until the applicator is in the field.
In light of these and other limitations, reliance on pre-prepared prescriptions that are complex enough to effectively and efficiently take advantage of all of the variables and options provided by modern planting techniques is not an acceptably reliable or realistic approach.
It is desirable, therefore, to provide a new system, method and apparatus for automatically varying parameters such as the application rate and control of sections or individual nozzles of equipment applying agricultural products, on-the-fly, while in the field, as a function of the data recorded at the time of planting. It is also desirable to automatically vary application rates and positioning of the agricultural product as a function of previously recorded GPS coordinated planting data indicating actual plant population, variety, gaps, etc., and as a function of GPS-referenced present position of the application equipment in the field. It is further desirable to provide for on-the-fly, in-cab adjustments to, and/or scaling of application parameters to further modify application rates and placement of the agricultural product, while in the field.

Automatic application rate and section control based on actual planting data


The method of landing a flying wing type aircraft in a crosswind includes the steps of disengaging the nose landing wheel upon impact with the runway so that it is free to castor; and thereafter, engaging the nose wheel after a specific time period after the nose wheel impacts the runway such that the nose wheel is steerable. The system for landing a flying wing type aircraft in a crosswind on a runway includes a steering system for steering the nose wheel, the steering system having a first condition wherein it controls the angular position of nose wheel and a second condition wherein the wheel is free to castor. A control system moves the steering system from the first condition to the second condition upon the wheel contacting the runway and moves the steering system back to the first condition after a specified time after the wheel contacts the runway.

1. Field of the Invention
The invention relates to the field of aircraft and, in particular, to a system and method for landing an unmanned tailless or flying wing type aircraft in a crosswind.
2. Description of Related Art
Flying wing or tailless aircraft have a particularly unique problem. They have no vertical surfaces to provide a lateral force to control the effect of a crosswind during landings where the aircraft's flight path is at an angle to the longitudinal axis thereof. While the tailless aircraft can land flat, its wheels will strike the runway with a larger lateral offset than a conventional aircraft with vertical surfaces. The nose wheel is in front of the center of gravity (CG) and the side force generated by the wheel is very unstable. The offset in the angle means that when the aircraft touches down there will be a sudden lateral jerk in the direction the wheels are pointing. The resulting acceleration will cause one wing tip to dip or in a worst case, it can result in a ground loop.
U.S. Pat. No. 5,523,921 Aircraft Steering System And Method For Large Aircraft Having Main Landing Gear Steering During Low Taxi Speed While Nose Gear is Castored by H. C. Ralph discloses the concept of allowing the nose wheel to castor so that differential braking of the main landing gear can be used to turn the aircraft. The nose wheel landing gear includes a system to allow for turning with the nose wheel, but allows it to castor on command. The nose wheel steering system is described in Great Britain Patent No.: 879,279 Improvements Relating To Steering Mechanism For An Aircraft Ground Wheel Mounting by H. Cyril, et al. and is herein incorporated by reference.
Thus, it is a primary object of the invention to provide process to allow a tailless aircraft to land in a crosswind.
It is a further object of the invention to provide a process to allow a flying wing type aircraft to land in a crosswind by reducing the adverse effect at the moment of touchdown due to crabbing of the aircraft in a crosswind.

System and method for landing a tailless aircraft in a crosswind


Compiler and software product for compiling intermediate language (IL) bytecodes, such as Microsoft IL (MSIL) instructions into Java bytecodes, are provided. The provided compiler decodes the IL instructions, generates the stack content, and produces Java bytecodes based on the stack content. Furthermore, the compiler is specially designed to allow a programmer to develop software applications using the .Net framework that could be easily executed using a Java runtime environment.

The Microsoft® .NET framework is a new platform for building integrated, service-oriented, applications to, meet the needs of today's and future Internet businesses. The .Net platform allows developers to take better advantage of technologies than any earlier Microsoft platform. Specifically, the .NET platform provides for code reuse, code specialization, resource management, multi-language development, security, deployment and administration.
A .NET application can be executed on any platform that supports the .NET common language runtime (CLR). It is further possible that a version of the CLR be built for platforms other than Windows. The .Net platform allows different programming languages to be integrated with one another. For example, it is possible to create a class in C++ that is derived from a class implemented in Visual Basic. The programming languages supported by the .Net platform includes, but are not limited to, C++ with managed extensions, C#, Visual Basic, Pascal, Cobol, Java, JScript, and many others. However, the source code written in these languages requires the CLR engine in order to execute.
Reference is now made to FIG. 1, which is a prior art illustration of a progression of a .Net application through execution by a CLR engine 140. Once, the .Net source code 110 has been written in one of the programming languages mentioned above, it is first run through .Net compiler 120. .Net compiler 120 comprises a plurality of compilers, each targeted to a different language supported by the .Net platform. .Net compiler 120 generates the Microsoft intermediate language (MSIL) instructions. The MSIL instructions are arranged in assembly files 130. The MSIL includes instructions that create and initialize objects, call virtual methods on objects, raise and catch exceptions for error handling and manipulate array elements directly. The MSIL is central processing unit (CPU) independent, and as a result the MSIL instructions cannot be executed directly on a host CPU. Hence, CLR engine 140 must first compile the MSIL instructions into native CPU instructions. Generally, in order to ensure good performance, CLR engine 140 compiles the MSIL instructions as functions that are then called for execution.
Recently, the Java programming environment has gained popularity. The Java programming language is designed to be portable enough to be executed on a wide range of computers, ranging from small devices, e.g., PDA's, cell phones, and smart cards, up to supercomputers. Computer programs written in the Java programming language are compiled into Java bytecode instructions that are suitable for execution by a Java virtual machine (JVM).
FIG. 2 is a prior art illustration of the progression of a Java application through execution by a JVM. Java source code 210 includes a class with its associated methods written in Java. Source code 210 is then input into Java bytecode compiler 220, that compiles the source code into Java bytecodes. Java compiler 220 outputs Java class files 230 that include the bytecodes for the Java program. The Java bytecodes are virtual machine instructions that are executed by an interpreter. Typically, virtual machine instructions are generic, namely they are not designed for any specific CPU or computer architecture. The Java class file is then input into JVM 240. JVM 240 is an interpreter that decodes and executes the bytecodes of the Java class file. A conventional virtual machine's interpreter decodes and executes the Java bytecode instructions, one instruction at a time, during execution, i.e., at runtime.
It should be noted that both MSIL and Java bytecodes are stack based object-oriented languages. Stack-based languages require an efficient stack representation, fast procedure calls, and fast compilation.
It should be emphasized that Java applications can be executed either on a CLR engine or on a JVM, while .Net applications can be executed only on a CLR engine. Therefore, applications designed with the .Net platform cannot execute on a JVM. As a result, programmers cannot integrate the advantages inherent to .Net with the capabilities provided by the Java runtime environment. For example, a large number of Web applications are written in the Visual Basic programming language, however, executing those applications in a Java environment is impossible in the currently available technology.
Stack-based developments are known in the art, such as U.S. Pat. No. 5,668,999, System and Method for Pre-Verification of Stack Usage in Bytecode Program Loops, by Gosling, which features a virtual stack for temporarily storing stack information. U.S. Pat. No. 6,205,577, Interpreter for Stack-Based Languages, by Grove provides a multi-state interpreter for a stack-based programming language.
A bytecode interpreter was disclosed in U.S. Pat. No. 5,740,441, Bytecode Program Interpreter Apparatus and Method with Pre-Verification of Data Type Restrictions and Object Initialization, by Yellin, et al.
Recent compiler developments in the art include: U.S. Pat. No. 5,768,593, Dynamic Cross-Compilation System and Method, by Walters, et al;
U.S. Pat. No. 6,295,642, Method and Apparatus for Partial Just in Time Compiling in a Data Processing System, by Blandy;
U.S. Pat. No. 6,484,313, Compiling and Persisting of Intermediate Language Code, by Trowbridge, et al; and
U.S. Pat. No. 6,327,1702, Generating a Compiled Language Program for an Interpretive Runtime Environment, by Sauntry, et al.
However, none of the above patents relate to a Java bytecode platform.
Therefore, there is a need for a method that overcomes the limitations of prior art by providing a compiler that decodes the MSIL instructions and produces Java bytecodes instructions.

Compiler and software product for compiling intermediate language bytecodes into Java bytecodes


A method for controlling a suspension component of a vehicle, in which a control unit of the suspension component continuously generates a plurality of control requirements according to a generation clock frequency, each requirement comprising a control value, for an actuator of the suspension component. A bus system of the vehicle continuously transmits to the actuator the control requirements generated by the control unit according to a transmission clock frequency. The actuator calculates a target output value for the suspension component from the control value of each transmitted control requirement and an actual output value of the suspension component, and adjusts the suspension component corresponding to the calculated target output value.

Vehicles are used for a movement relative to a ground that can be driven over, for the most part a roadway, such as, e.g., a street. Therefore, every vehicle comprises a so-called suspension, which is configured to introduce into the ground below it a gravitational force of the vehicle as well as forces and torques generated by the vehicle and acting on the movement of the vehicle, or to absorb the corresponding counter-forces and counter-torques proceeding from the ground.
Every suspension usually comprises a chassis frame, a plurality of wheels that are introduced on the chassis and that are rotatable around a transverse axis and partially around a yaw axis of the vehicle, which is perpendicular to the transverse axis, as well as a plurality of sensors and/or actuators that are for the most part electrically controlled and assigned to the wheels. The actuators are designed to apply forces and/or torques to the wheels, such as, for example, a drive system and a brake system, or to absorb forces and/or torques operating on the wheels, such as, for example, a spring suspension system.
The suspension thus becomes of central importance with respect to driving safety of the vehicle and driving comfort of the vehicle's passengers. Correspondingly, one aims at further optimizing suspension components and better matching them to each other, in order to ensure the driving safety and the driving comfort even in extreme driving situations and for inexperienced drivers of the vehicle.
Thus, DE 43 05 155 A1 discloses a control system for a suspension component, namely a brake system of a vehicle. The control system comprises a processing unit and actuators associated with the processing unit; wheel brakes of the vehicle are assigned to said actuators. The processing unit classifies driving situations of the vehicle and forms an adjustment signal for selected actuators that is dependent on the class of the driving situation, in order to apply a braking pressure to associated wheel brakes. With the described brake system, a braking distance and a lane deviation are reduced in the case of a braking, and in this way, the stability of the vehicle is improved.
In the case of a so-called active suspension, actuators of the suspension are also controlled independently as a function of a driving situation by a control unit of the vehicle, in order to counteract unfavorable operating states of the vehicle or to ensure a certain desired drive performance of the vehicle, which can also be selected by the driver, as the case may be.
Correspondingly, DE 10 2012 202 684 A1 discloses a method for controlling suspension components of a vehicle, namely wheel drives and wheel brakes. In this method, a drive torque and/or a braking torque are applied to the wheels of the vehicle, if an operating parameter of the suspension that is detected by a sensor and is relative to stability exceeds a pre-determined activation threshold. The stability of the vehicle is improved due to the fact that the control strategy is adapted in a variable manner, wherein, dependent on a driving situation, the activation threshold is decreased and/or an intensity and/or a gradient of a control override is increased.
Of course, in the preceding method, an automatic control override is always generated only after exceeding the activation threshold. In spite of a dynamically adjusted activation threshold that is dependent on the driving situation, the stabilizing control override may consequently be delayed under certain circumstances. The aim is therefore to dynamically fine-tune suspensions based on prognoses relating to upcoming driving situations.
WO 2005/087521 A1 discloses such a method and a corresponding device for adapting a reaction of a vehicle to a driving maneuver aimed at by a driver, for example, traveling along a curve. The aimed-at driving maneuver is recognized on a target value of a manipulated variable of a suspension component, this value being adjusted by the driver: a target steering angle, in this example. Proceeding from the actual value of the manipulated variable of the suspension component, the reaction of the vehicle to an adjusted target value is simulated, and a suitable roll moment distribution of the vehicle is automatically established. In other words, a suspension characteristic and thus a drive performance of the vehicle is carefully changed, adapting to a prognosis.
Modern vehicles comprise central bus systems, with which control units, sensors, and actuators are connected in electrically conducting manner. A central bus system transmits sensor signals that are continually generated by the sensors to the control units according to a specific transmission protocol, and transmits control requirements, which are generated by the control units and comprise control values that are calculated from the sensor signals, from the control units to the actuators. The actuators calculate corresponding target output values from the transmitted control values and adjust the associated suspension component to the calculated target output value, starting from an actual output value of the suspension component.
However, the bus system, the sensors, the control units, and the actuators may each have different clock frequencies. In other words, in many cases, a transmission clock frequency of the bus system, generation clock frequencies of the control units, and calculation clock frequencies of the actuators are different. Based on the lack of synchronicity, but also as a consequence of latency times, different generation and calculation times, as well as in the case of a loss of control requirements caused by interference in the bus system can lead to an undesired course of adjustment of suspension components.
For example, a time course of a control value provided continually by a control unit, despite a uniform generation of corresponding control requirements, in the case of the actuator, can lead to an abrupt adjustment of suspension components, which is detrimental to driving safety and/or to driving comfort. It should be noted in this connection that discontinuities in the course of adjustment having a short duration of 2 ms are perceived by the driver of the vehicle and are felt to be unpleasant or disruptive.

Control of a suspension component of a vehicle


A liquid material drawing method includes: performing a first discharging step in which at least one of the droplets the liquid material is discharged from at least one of a plurality of nozzles for each of a plurality of pixel regions; observing and capturing an image of the pixel regions on a workpiece in which the droplets are discharged; computing a distance in a first direction and a distance in an orthogonal second direction between barrier parts on the workpiece and a landing position of the at least one of the droplets in the image of the pixel regions; and correcting arrangement information including a relative positioning of the nozzles and the workpiece, which is used to arrange a prescribed number of the droplets as dots for each of the pixel regions, based on the distance in the first direction and the distance in the second direction.

1. Technical Field
The present invention relates to a liquid material drawing method that uses a liquid droplet discharge method, to a color filter manufacturing method, and to an organic EL element manufacturing method.
2. Related Art
Japanese Laid-Open Patent Application Publication No. 2003-275650 discloses an example of known drawing systems that use a droplet discharge method include a drawing method (drawing system) for drawing one or more chip-shaped regions on a workpiece by causing functional droplets to be selectively discharged from a plurality of nozzles provided to a functional-droplet discharge head while causing the functional-droplet discharge head to move relative to the workpiece based on data that are stored in a recording medium.
In the abovementioned drawing system, the functional droplets are discharged and drawn on the workpiece based on discharge pattern data of each nozzle that are stored in the recording medium.
The abovementioned discharge pattern data are generated based on at least chip information relating to the position of a chip formation region on the workpiece, pixel information relating to the arrangement of pixels in a chip formation region, and nozzle information relating to the arrangement of the nozzles with respect to the workpiece.
Japanese Laid-Open Patent Application Publication No. 2006-130383 discloses an example of known methods for detecting the landing position of the discharged functional droplets include a dot deviation detection method and a dot deviation detection device capable of simply and rapidly detecting a dot misalignment obtained from the landing of a droplet discharged from a nozzle of the droplet discharge head onto a detection object.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved liquid material drawing method, color filter manufacturing method, and organic EL element manufacturing method. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.

Liquid material drawing method, color filter manufacturing method, and organic EL element manufacturing method


A contact screw for conductive cores of a shielded cable, said screw being provided to be moved axially in a connecting device by threading; it has a shank with screw threading and a contact tip the section of which provided for penetration of the cable insulation and the shield is provided with a coating of insulating material, the exterior surface of the coating being provided with threading whose pitch is greater than the pitch of the screw threading of the shank.

The problem, particularly in the case of flat cables that have energy transmission and data transmission cores, lies in piercing the data conductor in the shielded cable without the screw coming in contact with the shield (electrically conductive material), while in the process achieving good contact resistance between the end of the contact tip and the conductor and retaining high dielectric strength between shield and conductor.
In the past this object has been attained by means of a contact screw with an end casing of hard insulating material which extends through the cable jacket, the shield, and the core insulation when the conductor is pierced. One disadvantage of this solution is that the force of penetration is transmitted to the insulating material and the shield is drawn toward the conductor, something which disadvantageously reduces the distance between shield and conductor.


In an automatic gain control circuit of a demodulating circuit, power values of pieces of symbol information I and Q of in-phase components and quadrature components of a modulated signal are calculated, a power difference between each power value and an ideal power value is detected, and an AGC control signal is produced to adjust a gain of the modulated signal according to the AGC control signal in a demodulating system including the demodulating circuit. Therefore, when an amount of noise included in the modulated signal is low, an average value of the power differences is reduced to zero, and the modulated signal can be correctly demodulated to a demodulated signal. To correctly demodulate the modulated signal including a large amount of noise, after the conversion of the AGC control signal, a sweep counter value is added to the AGC control signal so as to minimize a bit error rate of the demodulated signal. Thereafter, the ideal power value is corrected to reduce the average value of the power differences to zero even though the AGC control signal is corrected.

1. Field of the Invention
The present invention relates to an automatic gain control circuit and an automatic gain control method which are used for a circuit for controlling the amplitude of an input signal according to a multi-phase modulation method or a quadrature modulation method.
2. Description of Related Art
A device such as a personal computer composed of digital circuits has been recently widespread, and digital data is transmitted and received through a communication network. Also, in the communication service such as television broadcasting, to increase a utilization ratio of a limited usable frequency band, service based on the digital communication technology has been put to practical use. In this digital communication technology, the quadrature amplitude modulation (hereinafter, called QAM) is often used as one of digital modulation types.
In the QAM, a sine function and a cosine function orthogonal to each other are used, digital data is transformed into both amplitude information and phase information, and the amplitude information and the phase information are transmitted.
FIG. 6 is a graphic view showing the vector location of 16-point QAM in which four values are given to each of an in-phase signal and a quadrature signal. In FIG. 6, the I-axis indicates the amplitude of a cosine wave denoting an in-phase component, and the Q-axis indicates the amplitude of a sine wave denoting a quadrature component. Each signal point (hereinafter, called symbol) designated by a black point in FIG. 6 indicates a composite vector of both the sine wave and the cosine wave, the symbols denote discrete signals output at regular intervals, and each symbol has 4-bit information.
Also, the phase shift keying (hereafter, called PSK) is known as one of the digital modulation types. In this PSK, a sine function and a cosine function orthogonal to each other are used in the same manner as in the QAM, digital data is transformed into phase information, and the phase information is transmitted.
FIG. 7 is a graphic view showing the vector location of 8-phase PSK in which the phase of an in-phase signal and the phase of a quadrature signal are respectively divided into eight pieces. In FIG. 7, the I-axis indicates the amplitude of a cosine wave denoting an in-phase component, and the Q-axis indicates the amplitude of a sine wave denoting a quadrature component. Each signal point (hereinafter, called symbol) designated by a black point in FIG. 7 indicates a composite vector of both the sine wave and the cosine wave, the symbols denote discrete signals output at regular intervals, and each signal has 3-bit information.
In cases where the digital service is performed by using a wire transmission line such as a cable, distortion relating to the amplitude direction of a modulated signal hardly occurs in the wire transmission line. Therefore, the QAM is generally used for the communication service using the wire transmission line. In contrast, in case of the satellite communication using a radio transmission line, distortion relating to the amplitude direction of a modulated signal easily occurs due to characteristics of an amplifier placed at the relay point of a satellite. Therefore, the PSK is generally used for the communication service using the radio transmission line.
FIG. 8 is a constitutional view showing a general carrier wave reproducing system (hereinafter, called a demodulating system) for both a wave modulated according to the QAM and a wave modulated according to the PSK. In FIG. 8, 1 indicates a tuner for receiving a modulated signal modulated according to the QAM or PSK, 2 indicates a band pass filter, 3 indicates a gain changeable amplifier (hereinafter, called an AGC amplifier), 4 indicates an oscillator, 5 indicates a frequency changer, 6 indicates an analog-to-digital converter (hereinafter, called AID converter), and 7 indicates a carrier wave reproducing circuit (hereinafter, called a demodulating circuit).
An operation of the demodulating system will be described.
A high-frequency modulated signal such as a ground wave or a satellite wave transmitted through a wire transmission line or a radio transmission line is received in the tuner 1, and a high frequency of a transmission band in the modulated signal is changed in the tuner 1 to a constant frequency called an intermediate frequency ranging from 50 to 30 MHz.
Thereafter, noise existing out of the transmission band of the intermediate frequency is removed from the modulated signal in the band pass filter 2, the intermediate frequency of the modulated signal is changed to a low-band frequency in the frequency changer 5, and the modulated signal is input to the A/D converter 6. In the A/D converter 6, the analog modulated signal is converted into a digital modulated signal, and the digital modulated signal is input to the demodulating circuit 7. Thereafter, in the demodulating circuit 7, a digital process is performed for the input modulated signal to demodulate the input modulated signal to a demodulated signal, and digital data included in the demodulated signal is obtained.
In this case, to maintain a conversion precision in the A/D converter 6, the demodulating circuit 7 is required to maintain an average amplitude of the analog modulated signal input to the A/D converter 6. Therefore, an operation for maintaining a gain of the signal input to the A/D converter 6 is performed by the AGC amplifier 3 under the control of an AGC control signal output from an automatic gain control circuit of the demodulating circuit 7.
FIG. 9 is a constitutional view showing a general demodulating circuit. In FIG. 9, 11 indicates a multiplier, 12 indicates another multiplier, 13 indicates a low pass filter (hereinafter, called LPF), 14 indicates another low pass filter (hereinafter, called LPF), 28 indicates a conventional automatic gain control circuit, 15 indicates a de-rotator formed of a complex multiplier, 16 indicates a phase comparator, 17 indicates a loop filter, 18 indicates a numerical control oscillator (hereinafter, called NCO), 19 indicates a decoder, and 20 indicates an error correction circuit.
The input modulated signal input to a data input terminal of the demodulating circuit 7 is processed in digital circuits because the input modulated signal has been already converted into digital values in the A/D converter 6. The phase of the input modulated signal is detected in the multiplier 11 by using a local oscillating signal having a waveform of a cosine wave. Also, the phase of the input modulated signal is detected in the multiplier 12 by using a local oscillating signal having a waveform of a sine wave. Therefore, the input modulated signal is divided into in-phase components of symbols and quadrature components of the symbols. The in-phase component and the quadrature component of each symbol is orthogonal to each other. Here, each of the local oscillating signals respectively having a fixed frequency is output from a local oscillator. The in-phase components obtained in the multiplier 11 are input to the LPF 13, the quadrature components obtained in the multiplier 12 are input to the LPF 14, and the spectral reshaping is performed for the in-phase components and the quadrature components. Here, a frequency characteristic of the LPF 13 is the same as that of the LPF 14.
Each of the LPFs 13 and 14 is formed of a roll off filter or a root roll off filter in which a transfer characteristic required for the prevention of an inter-symbol interference in the digital data transmission is obtained. Therefore, in cases where the transfer characteristic is combined with a filter characteristic of a transmission end of the modulated signal, a raised cosine characteristic can be obtained to prevent the inter-symbol interference.
Both the in-phase component and the quadrature component of each symbol of the input modulated signal output from the LPFs 13 and 14 are input to the automatic gain control circuit 28. In the automatic gain control circuit 28, a power value of each symbol of the input modulated signal is calculated from information of the symbol, the calculated power value of each symbol is compared with a referential power value which corresponds to the modulation type adopted for the input modulated signal, and a difference between the power value of each symbol of the input modulated signal actually received and the referential power value is detected. Here, a referential power value corresponding to each of a plurality of modulation types is stored in advance in the automatic gain control circuit 28. Thereafter, an AGC control signal indicating the detected power differences of the symbols is output from the automatic gain control circuit 28 of the demodulating circuit 7 and is received in both an AGC amplifier arranged in the tuner 1 and the AGC amplifier 3. Therefore, the gain of the analog modulated signal input to the A/D converter 6 is maintained to a constant value according to the AGC control signal.
Also, the in-phase components and the quadrature components of the symbols of the input modulated signal output from the LPFs 13 and 14 are received in the de-rotator 15. Also, a data conversion digital signal SIN obtained from an analog sine signal and a data conversion digital signal COS obtained from an analog cosine signal are output from the NCO 18 and are received in the de-rotator 15. In the de-rotator 15, a phase shift and a frequency shift occurring between the in-phase components and the quadrature components of the input modulated signal are corrected.
Thereafter, the in-phase components and the quadrature components of the symbols corrected in the de-rotator 15 are received in both the decoder 19 and the phase comparator 16 as pieces of symbol information. In the decoder 19, the pieces of symbol information are converted into bit string data. In the phase comparator 16, an ideal phase of each symbol is predicted, and a difference between the ideal phase of the symbol and the phase of the symbol actually received is detected as a phase error for each symbol. Thereafter, each detected phase error is smoothed in the loop filter 17, and a digital signal indicating the smoothed phase errors is input to a frequency control terminal of the NCO 18. In the NCO 18, a signal having a frequency proportional to the frequency of the digital signal is produced. Also, the NCO 18 has a data converting function. Therefore, the data conversion signal SIN and the data conversion signal COS respectively having a frequency proportional to the frequency of the digital signal are output from the NCO 18 and are received in the de-rotator 15 as information used to correct both a phase shift and a frequency shift of the input modulated signal.
When both the phase shift and the frequency shift of the input modulated signal are removed from the output of the de-rotator 15, the bit string data output from the decoder 19 agrees with the digital data included in the modulated signal. Therefore, the modulated signal is demodulated to demodulated data, and the digital data is reproduced.
However, error is included in the demodulated data due to the influence of noise which occurs in dependence on environments of the transmission line. The relation between an amount of noise and a bit error rate of the demodulated data is theoretically determined for each modulation type. Because noise necessarily occurs in all types of transmission lines, the bit error necessarily occurs in the modulated signal transmitted through any type of transmission line.
Also, the data processing is performed for the demodulated data in latter stages of the demodulating system on the assumption that the modulated signal received is correctly demodulated to the bit string data. Therefore, in cases where bit error exists in the bit string data, even though a home page of an internet is, for example, opened, a picture registered in the home page is not displayed. To remove the bit error from the bit string data, the error correcting circuit 20 is arranged in the demodulating system.
Therefore, even though the bit string data output from the decoder 19 includes bit error, when a bit error rate of the bit error included in the bit string data is equal to or lower than an allowable error bit rate, the bit error included in the bit string data can be corrected in the error correcting circuit 20 so as to make the bit string data perfectly agree with the digital data output from a transmission end of the modulated signal. The error correcting circuit 20 is formed of a trellis decoder, a Viterbi decoder, a Read-Solomon decoder, or the combination of those decoders. Therefore, an output signal OUT of the error correcting circuit 20 denotes the output of the demodulating system.
FIG. 10 is a constitutional view showing the conventional automatic gain control circuit 28 arranged in the demodulating circuit 7.
In FIG. 10, 21 indicates a power calculating circuit for performing a square calculation for each piece of symbol information. 22 indicates a root calculating circuit for calculating a square root of a calculation result obtained in the power calculating circuit 21 as a power value of one symbol for each symbol. 23 indicates an adder for subtracting a reference value (hereinafter, called AGCR) from a power value of each symbol output from the root calculating circuit 22 and outputting a power difference for each symbol. The reference value expresses an ideal power value of the symbols relating to the corresponding modulation type, and a plurality of ideal power values are prescribed and stored for a plurality of modulation types in one-to-one correspondence. 24 indicates a multiplier for multiplying the power difference output from the adder 23 by a foxed gain (hereinafter, called AGCG) for each symbol. 25 indicates a loop filter for averaging a plurality of multiplication results of the multiplier 24. 26 indicates a pulse width modulator for producing the AGC control signal AGCPWM in which the output of the loop filter 25 is expressed by a pulse width.
Next, an operation of the conventional automatic gain control circuit 28 will be described.
Pieces of symbol information I of the in-phase components of the symbols and pieces of symbol information Q of the quadrature components of the symbols are output from the LPFs 13 and 14 and are received in the power calculating circuit 21. In the power calculating circuit 21, the piece of symbol information I of each in-phase component is squared to obtain a squared value I2, the piece of symbol information Q of each quadrature component is squared to obtain a squared value Q2, and the squared value I2 and the squared value Q2 are added together to obtain I2+Q2 for each symbol. Thereafter, the square root of the calculation result I2+Q2 of the power calculating circuit 21 is extracted in the root calculating circuit 22 for each symbol, and a power value √{square root over ( )}(I2+Q2) of each symbol is obtained. Here, the root calculating circuit 22 is generally formed of a read only memory.
Thereafter, the power value of each symbol is compared with the AGCR, which denotes a reference value expressing an ideal power value of the symbols and is prescribed for the corresponding modulation type, in the adder 23, and a difference between the power value and the AGCR is detected for each symbol. The AGCR is obtained by calculating an average of the power values of all symbols positioned according to an ideal symbol location of the symbols, so that the AGCR denotes an ideal power value. The value of the AGCR depends on the modulation type. Thereafter, the difference between the power value of each symbol and the AGCR denoting an ideal power value is multiplied by the AGCG denoting a fixed gain in the multiplier 24, and an average of multiplied values obtained in the multiplier 24 is calculated in the loop filter 25. The average value obtained in the loop filter 25 is changed to the AGC control signal AGCPWM having a direct current component in the pulse width modulator 26 (or a digital-to-analog converter not shown), and the direct current component of the AGC control signal is fed back to both the AGC amplifier 3 and an AGC amplifier of the tuner 1 so as to control the amplitude of the signal input to the A/D converter 6 to a constant value.
Next, another conventional automatic gain control circuit operated according to a peak power control method is described.
FIG. 11 is a constitutional view of another conventional automatic gain control circuit. In FIG. 11, 31 indicates a power calculating circuit, 32 indicates a threshold value counter, and 33 indicates a pulse width modulator. A peak power control method is often used in a demodulating system based on the PSK in which phase information is only used and the amplitude of a modulated signal, or a power value of each symbol, is always constant.
Pieces of symbol information I of the in-phase components of the symbols and pieces of symbol information Q of the quadrature components of the symbols are output from the LPFs 13 and 14 and are received in the power calculating circuit 31. In the power calculating circuit 31, the piece of symbol information I of each in-phase component is squared, the piece of symbol information Q of each quadrature component is squared, and the squared value I2 and the squared value Q2 are added together to obtain I2+Q2 for each symbol. Thereafter, the square root of the calculation result I2+Q2 of the power calculating circuit 31 is extracted in a root calculating circuit (not shown) for each symbol, a power value √{square root over ( )}(I2+Q2) of each symbol is obtained. Therefore, a power value of each symbol of the input modulated signal is calculated. In this case, in cases where the input modulated signal is produced according to the PSK, because the value I2+Q2 is constant, the calculation of the square root of the calculation result I2+Q2 in the root calculating circuit can be omitted.
Thereafter, in the threshold value counter 32, the number of symbols, of which the calculated power values are higher than a first threshold value obtained by adding a constant value to the ideal power value, is counted as a counted value during a predetermined time period, or the number of symbols, of which the calculated power values are lower than a second threshold value obtained by subtracting a constant value from the ideal power value, is counted as a counted value during a predetermined time period. The counted value is used to increase or decrease the amplitude of the modulated signal input to the A/D converter 6. In detail, the counted value of the threshold value counter 32 is changed to an AGC control signal AGCPWM having a direct current component in the pulse width modulator 33 (or a digital-to-analog converter not shown), and the direct current component of the AGC control signal is fed back to both the AGC amplifier 3 and an AGC amplifier of the tuner 1 so as to control the amplitude of the modulated signal input to the A/D converter 6 to a constant value.
Accordingly, the amplitude of the modulated signal input to the A/D converter 6 can be controlled by calculating a degree of control for both the AGC amplifier 3 and the AGC amplifier of the tuner 1 according to only the power information indicated by the symbol information I and Q.
However, there is probability that a large amount of noise is included in the input modulated signal, a reflected signal generated due to the mismatching of the transmission lines is superposed on the symbol information I and Q, and/or unnecessary radiation such as spurious radiation occurs in the transmission frequency band of the input modulated signal. In this case, because a power value of an unnecessary signal included in the symbol information I and Q is added to the power information indicated by the symbol information I and Q, the power value indicated by the symbol information I and Q cannot be correctly calculated. As a result, the amplitude of the modulated signal input to the A/D converter 6 becomes unstable so as to be out of the dynamic range of the A/D converter 6, the A/D conversion is not correctly performed in the A/D converter 6, the decoding in the decoder 19 of the demodulating circuit 7 is not correctly performed, and a bit error rate of the bit string data output from the decoder 19 becomes worse. Therefore, even though the modulated signal received in the tuner 1 includes a small amount of noise, there is probability that a bit error rate of the bit string data output from the decoder 19 exceeds the allowable error bit rate, and the bit error included in the bit string data cannot be perfectly corrected in the error correcting circuit 20. Accordingly, a problem has arisen that the demodulating system including the automatic gain control circuit is unstably operated.

Automatic gain control circuit and automatic gain control method


A method, apparatus, article of manufacture, and system, the method including, in some embodiments, providing a differential clock ganging structure to receive complementary differential clock signals, the differential clock ganging structure outputting clock ganging output signals, providing a source termination structure for each of the clock ganging output signals, and providing an inductance and capacitance compensation structure to receive an output of the source termination structure and to connect to a terminal interconnect for at least one of the clock ganging output signals.

A reliability and stability of a device, system, platform, or operating environment may depend on the device, system, platform, or operating environment operating within design specifications. A number of devices, systems, platforms, and operating environments use reference voltages. Clock skew tolerances and input edge rates are becoming increasingly smaller as systems become more complex and faster.
A number of attempts have been proposed to compensate for reference differential clock skew. In particular, pin-to-pin output skew and/or driver induced skew have been addressed by shortening propagation delay differences between clock input-to-output paths inside of a circuit and IC package. However, such approaches are limited in effectiveness and potential gains by, for example, the need to modify the circuits and IC packages.

Method and system for clock routing and compensation


An improved rock picker system includes a prime mover, with an operator's cab and towing apparatus; windrows detachably and foldingly mounted to the prime mover front; a collector; a separator; a transfer apparatus; a dump trailer detachably connectable to the prime mover towing apparatus; an hydraulic power supply in fluid communication with the hydraulic loads; and, controls for controlling the hydraulic power supply and hydraulic loads individually. Controls include a plurality of remotely operated hydraulic control valves corresponding to the hydraulic loads and a control panel in electrical communication with the remotely operated hydraulic control valves, and speed controllers for controlling the speed of the hydraulic loads.

Since the introduction of plows to agriculture the need to remove rocks from crop fields has been a pressing concern. Rocks contacting plows can break the plow blades or become jammed in the moving equipment causing gears and connectors to become misaligned or damaged. Rocks can also interfere with some types of harvesting equipment and other agricultural machinery.
Problems caused by rock damage to agricultural equipment go beyond the damaged equipment. Agriculture is a time-sensitive occupation where delays in planting or harvesting while equipment is repaired can cause the loss of part, or all, of a crop. Moreover, with more and more pressure to absorb farmland into urban developments there is greater imperative to put marginal agricultural land to use, such as locations with high rock content in the soil.
Existing rock picker apparatus are not able to optimize their operation to varying soil/terrain conditions. They are unable to automatically adjust their collection systems to accommodate rocks of varying sizes. Existing systems cannot easily be optimized by adjusting speed ratios and relative positioning of components. Adjustment is difficult in this regard, generally requiring machine shutdown while a mechanic (or mechanics) make physical adjustments through levers or by replacing gearboxes and belts. Operators cannot quickly stop individual components or raise them to clear obstacles thereby creating potentially unsafe conditions. Operators cannot reverse the direction of operation for components in the event of jams or for maintenance, leaving them very vulnerable to jamming by large rocks or non-rock obstacles, or due to very uneven ground. Additionally, existing systems have low storage volume for rocks removed from the field and they do not provide for easy offloading of rock. Existing apparatus generally require towing the rock picker and separator apparatus behind a tractor, which reduces their maneuverability and prevents the forward facing operator from monitoring equipment during operation. Existing apparatus have focused on particular pieces of technology or gadgets but have not solved the problem of integrating an efficient machine which can be operated by a single person from within an operating cab. Apparatus such as described by Fahrenholz, below, require complex customized mechanical linkages and gearing systems which are difficult to maintain, very exposed to damage and weather, and not amenable to optimization. Existing apparatus do not provide a feedwheel mechanism to provide positive capture for efficient transfer of material into a collector mechanism. All of these shortcomings severely impact efficiency and increase the amount of skilled labor required to clear fields—and thus increase costs.
Thus, there is a need for a self-propelled rock picker system that:
1) is capable of extracting, storing and dumping a large volume of rock from a field with a high rate of efficiency; 2) can recover quickly and safely from jammed components by operating components selectively in reverse; 3) provides easily adjustable component speeds, speed ratios and heights for optimizing according to field conditions and worn components; 4) enhances safety by providing for an emergency shutdown function for moving components without requiring engine shutdown; 5) is forward mounted so an operator can easily monitor equipment during operation; 6) is forward mounted for improved maneuverability; 7) allows operation of all components from the cab of a tractor or other prime mover; 8) includes a large capacity articulated trailer controllable from an operator's cab for dumping accumulated rocks; 9) includes a feedwheel for efficient collection of rock material; 10) can be retrofitted onto the frames of existing combine tractors; 11) is capable of clearing three acres of cleared land per hour; 12) can be folded by a single operator for transport or stowage; 13) does not require complex customized mechanical linkages and gear systems; 14) permits components to be changed to different size or style, which may require different speed ratios, without need to design new linkages, gearboxes, or belt systems; 15) facilitates use of remote operation of components; 16) facilitates use of effective safety control interlocks.
A number of devices have provided rock pickers, but lack the flexibility, safety, reliability and capacity of the present invention. Presently known art attempts to address this problem, but has not completely solved the problem. The following represents a list of known related art:
Reference:Issued to:Date of Issue:U.S. Pat. No. 7,028,460 B1FahrenholzApr. 18, 2006U.S. Pat. No. 4,345,655FahrenholzAug. 24, 1982U.S. Pat. No. 3,782,477FahrenholzJan. 1, 1974U.S. Pat. No. 3,117,631FahrenholzJan. 14, 1964U.S. Pat. No. 2,725,700FahrenholzDec. 6, 1955U.S. Pat. No. 6,702,034 B2ClaryMar. 9, 2004U.S. Pat. No. 6,041,866SmithMar. 28, 2000U.S. Pat. No. 5,310,008DauvinMay 10, 1994U.S. Pat. No. 5,027,906Jeannotte et alJul. 2, 1991U.S. Pat. No. 4,609,050Jacobs et alSep. 2, 1986U.S. Pat. No. 4,609,049MigdalSep. 2, 1986U.S. Pat. No. 4,319,641DegelmanMar. 16, 1982U.S. Pat. No. 4,301,869DuboisNov. 24, 1981U.S. Pat. No. 4,296,818Malinowski et alOct. 27, 1981U.S. Pat. No. 4,282,932AndersonAug. 11, 1981U.S. Pat. No. 4,221,265PrattSep. 9, 1980U.S. Pat. No. 4,153,114MorlockMay 8, 1979U.S. Pat. No. 4,059,158RangerNov. 22, 1977U.S. Pat. No. 4,040,489HulicskoAug. 9, 1977U.S. Pat. No. 3,739,855BlissJun. 19, 1973U.S. Pat. No. 3,431,979GregersonMar. 11, 1969U.S. Pat. No. 3,261,408SimonarJul. 19, 1966U.S. Pat. No. 2,924,284Cykler et alFeb. 9, 1960U.S. Pat. No. 2,686,394Kalaus et alAug. 17, 1954U.S. Pat. No. 2,363,682Madsen et alNov. 28, 1944U.S. Pat. No. 1,563,340ChristensonDec. 1, 1925U.S. Pat. No. 1,478,142OrtmannDec. 18, 1923U.S. Pat. No. 946,115EdensJan. 11, 1910U.S. Pat. No. 946,273RichardsJan. 11, 1910U.S. Pat. No. 624,852NugentMay 9, 1899U.S. Pat. No. 047,566QuimbyMay 2, 1865U.S. Pat. No. 019,430MaydoleFeb. 23, 1858
The teachings of each of the above-listed citations (which does not itself incorporate essential material by reference) are herein incorporated by reference. None of the above inventions and patents, taken either singularly or in combination, is seen to describe the instant invention as claimed.
Fahrenholz in several patents teaches rock picker systems: U.S. Pat. No. 7,028,460 B1 (the Fahrenholz '460 patent); U.S. Pat. No. 4,345,655 (the Fahrenholz '655 patent); U.S. Pat. No. 3,782,477 (the Fahrenholz '477 patent); U.S. Pat. No. 3,117,631 (the Fahrenholz '631 patent); U.S. Pat. No. 2,725,700 (the Fahrenholz '700 patent).
The Fahrenholz patents (collectively referred to here as "Fahrenholz") teach towed rock picker systems utilizing windrows, drum separators, and complicated conveyor systems. Fahrenholz does not teach individually controlled components, but rather mechanically linked components using complicated systems of drive shafts, sprockets, chains and mechanically clutched belts, with all parts operating at fixed speed ratios. Fahrenholz does not teach the use of independent drive motors which are infinitely adjustable and reversible, and individually operable from the cab of a prime mover. Fahrenholz teaches conveyors using manual cable-actuated clutches, which require the operator to operate levers requiring significant strength and skill. Towed systems such as Fahrenholz reduce maneuverability and visibility. Fahrenholz does not teach a dynamically mounted feed wheel to handle rocks of varying sizes. Fahrenholz does not teach mounting a rock picking system forwardly for improved visibility and maneuverability. Fahrenholz does not teach the use of a foldable system which can be folded by a single operator for transport or stowage.
Fahrenholz '631 teaches a towed, single windrow apparatus for forming a windrow of rocks for a separate rock picker to collect. The apparatus utilizes a transverse-mounted frame supporting a roller powered by mechanical linkages from a tractor motor using a power-take-off (PTO).
Fahrenholz '655 teaches the use of a rock tumbler for separating rocks from soil, and windrows, but towed behind a tractor on a separate frame so that an operator cannot monitor the equipment while driving the tractor. Fahrenholz '655 teaches the use of mechanical belts and linkages for power transmission, with fixed gear ratios, preventing adjustment of component speeds, heights or depth of ground penetration. There is no provision for reversing components in the event of jams. The arrangement of the overlaid conveyor belts is complicated and difficult to maintain. The intermediate storage conveyor in Fahrenholz '655 does not have high capacity and can only be off-loaded while running certain other equipment, such as the rock tumbler, due to the mechanical linkages. Fahrenholz requires a second tractor to tow a collection trailer in parallel with the rock picker in order to provide adequate intermediate storage. This adds a second operator and can be difficult in uneven terrain. It can even lead to serious accidents if the tractors collide or the second tractor/trailer gets tangled with the conveyor system.
Thus, while the foregoing body of art indicates it to be well known to have a rock picker, the art described above does not teach or suggest a rock picker system which has the following combination of desirable features: (1) the system can be retrofitted to the frame of a standard combine tractor or other prime mover with the addition of a hydraulic power supply; (2) the hydraulic power supply can run off the prime mover engine or an independent APU for flexibility; (3) the system folds for transport on a flatbed truck; (4) speeds of all components are infinitely adjustable in order to optimize operation for different rock/soil conditions or worn components; (5) rotating components are reversible to enable recovery from jams; (6) hydraulic drives and cylinders are easily stopped in emergency, greatly improving safety; (7) front mounting providing an operator better visibility and safety; (8) front mounting providing improved maneuverability; (9) a large capacity articulated rock box providing rapid unloading into any bulk container, or directly into fill, by a single operator; (10) independently driven components allowing rapid change out of damaged/worn parts; (11) independently driven components permitting a single operator to control all operations from a position inside the cab of a prime mover; (12) ease of adjustability, maneuverability, and high capacity enabling a single operator to clear up to three acres per hour or more; (13) the ability to upgrade individual components; and (14) incorporates a feed wheel to increase efficiency of rock collection.
Still other features would be desirable. For example, existing systems do not facilitate closed loop automation and computerized control. Existing apparatus do not provide for replacement or upgrading of modular components. Existing apparatus do not provide a feed wheel to assist in the collection of larger rocks and breaking down aggregate chunks. Existing apparatus do not address the needs in the field with an integrated systems approach to address problems of optimization, upgradeability, maintenance, reliability, and safety.

Self-propelled transportable rock picker


A processing technique suitable for use with a search radar system which minimizes the false detection of targets. Rather than rely on a predetermined target trajectory, such as a straight line trajectory in range time space, the processing technique in accordance with the present invention is not based on a target dynamics model. The system in accordance with the present invention relies on past detections and assigns a confidence level to detections which are in the wake of a previous detection. A wake function is used to determine the amount by which each detection recursively accrues confidence based on a limited record of past detections. A detection is declared when the confidence level exceeds a predetermined threshold. As detections are encountered in range time space, such detections are used to form wakes based on the wake function which are used to assign confidence levels for future detections.

1. Field of the Invention
The present invention relates to an imaging filter and more particularly to an imaging filter for use with a search radar system which detects and tracks various targets including moving targets while suppressing false detection without relying on a straight line trajectory of the target.
2. Description of the Prior Art
Various imaging systems are known and used in a wide variety of applications. For example, search radar systems are known for imaging targets in a particular region of interest. Examples of such search radar systems are disclosed in U.S. Pat. Nos. 3,670,331; 3,680,100; 4,542,382 and 5,311,187; hereby incorporated by reference. Such search radar systems normally include a phased array antenna system or a mechanically rotatable antenna which sweeps a predetermined region of interest. The search radar systems are used for detecting and tracking various targets including moving targets and provide the range, azimuth and elevation of such targets in the predetermined region of interest as a function of time.
An important consideration in such search radar systems is the ability to suppress false detections. In general, radar systems including search radar systems normally compare the radiation reflected back to the radar system to a predetermined threshold. Reflected radiation having an energy level greater than the threshold is assumed to be reflected from a target and displayed or further processed. In order to further enhance the ability to detect and track moving targets and suppress noise, various other techniques have been developed. For example, "SEARCH RADAR DETECTION AND TRACK WITH THE HOUGH TRANSFORM PART I: SYSTEM CONCEPT", by B. D. Carlson, E. D. Evans and S L. Wilson,--IEEE Transactions on Aerospace and Electronics Systems, Vol. 30, No. 1, January 1994, pgs. 102-108; "SEARCH RADAR DETECTION AND TRACK WITH THE HOUGH TRANSFORM PART II: DETECTION STATISTICS", by B. D. Carlson, E. D. Evans and S. L. Wilson, IEEE Transactions on Aerospace and Electronics Systems, Vol. 30, No. 1, January 1994, pgs. 109-115, and "SEARCH RADAR DETECTION AND TRACK WITH THE HOUGH TRANSFORM PART III: DETECTION PERFORMANCE WITH BINARY INTEGRATION", by B. D. Carlson, E. D. Evans and S. L. Wilson, IEEE Transactions on Aerospace and Electronics Systems, Vol. 30, No. 1, January 1994, pgs. 116-125 disclose a processing technique in which the target trajectories are modeled as straight lines or low order polynomial curves. Any reflected radar energy greater than a threshold is then transformed into a parameter space where voting takes place based upon the expected straight line trajectory of the target. The parameters that receive the most votes are considered to represent the actual targets. Unfortunately, such a processing technique does not apply to target trajectories which do not fit the polynomial used as the model. For example, accurate tracking of people in a cluttered ground environment would produce erratic trajectories which would not fit such a model. As such, the processing technique as discussed in the above mentioned articles has limited utility.

Wake filter for false alarm suppression and tracking


A variable valve device for an internal combustion engine is equipped with a variable valve mechanism capable of changing the working angle of an intake valve while holding the maximum lift amount of the intake valve constant. The variable valve device retards the timing for closing the intake valve as the load of the internal combustion engine rises, and enlarges the working angle, while holding the timing for opening the intake valve constant. Operating characteristics of the intake valve are provided in accordance with the load of the internal combustion engine.

A variable valve device for an internal combustion engine transmits a turning force from a main drive shaft (a crankshaft) of the internal combustion engine to a camshaft via a timing chain and a timing belt, and rotates cams provided on the camshaft, thereby causing the cams to act on intake and exhaust valves (valves) to open/close the valves.
In recent years, there have been known variable valve mechanisms that are designed to change the working angle of a valve by changing the period in which a cam acts on the valve. Patent Document 1 discloses a variable valve system for an internal combustion engine that changes the lift amount of a valve with respect to a rotational position of a cam and changes the working angle of the valve by rotating a control shaft that is interposed between the cam and the valve, with the aid of a drive source. Patent Document 2 discloses a variable valve device that changes the working angle of a valve by interposing an annular disc between a flange portion of a sleeve coupled to a drive shaft and a flange portion of a camshaft, and making the center of the annular disc eccentric to cause the annular disc to rotate at non-constant speed.

Variable valve device of internal combustion engine