An apparatus and method for removing offset and shading from a video signal include a filter that convolves the video signal with a second derivative. The derivative can include first and second non-zero values centered about a third non-zero value, zero-filling between the first and third values, and zero-filling between the second and third values. The filter can be applied to Modulation Transfer Function measurement of an electro-optical sensor, in which offset and shading are removed from the sensor's video signal prior to Fourier analysis. Filtering and Fourier analysis are performed by a digital signal processor, which allows the measurement to be fully automated.

An electro-optical sensor is a device that converts radiant energy of a particular wavelength or range of wavelengths into an electrical signal. One example of an electro-optical sensor is a handheld TV camera, which converts images of visible light into an electrical signal that can be stored in electronic memory or displayed on a television screen. Another example of an electro-optical sensor is a Forward Looking Infrared sensor ("FLIR"), which converts images of infrared energy (i.e., heat), invisible to the human eye, into an electrical signal that can be displayed to a viewer. Because the FLIR can "see at night," it is widely used in military navigation and targeting systems and more recently in commercial security systems.
The capability of the electro-optical sensor to resolve the details of an object is referred to as the "resolution" of the sensor. Increasing the resolution allows the sensor to identify small objects at greater distances. High resolution allows the FLIR to identify an enemy target before that target gets too close.
Shading and offset diminish the resolution of the electro-optical sensor and, therefore, must be removed. When the target is small, the sensor's electronics must increase the gain and brightness to a high level in order to see the necessary detail in the target. Although the details of the target become more visible, the background becomes distorted by internal reflections and temperature gradients which result from the increases in gain and brightness. Offset refers to the average level of brightness (temperature) over an entire visible (infrared) sensor, and shading refers to gradients in brightness (temperature) across the sensor. These distortions make it harder to distinguish the target from the background.
Shading and offset cause additional problems when the resolution of the sensor is being measured. A standard measurement for sensor resolution is the Modulation Transfer Function ("MTF"). During MTF measurement, a very small target (e.g., a slit target) is presented to the sensor, and data samples of the sensor's video signal are collected. After all of the samples have been collected, shading and offset are manually removed from the samples and Fourier analysis is performed. This procedure requires an operator to manually derive the offset and shading from trends in data, and then subtract the offset and shading from the data.
Operator intervention during the MTF test is undesirable. The operator must have experience and training to determine trends in the data. Even then, the determinations are subjective and prone to error. Moreover, operator time is required to determine the trends, preventing the test results from being available in real-time.
It is an objective of the present invention to remove shading and offset from a video signal.
It is another objective of the present invention to increase the repeatability and accuracy of an MTF measurement.
It is yet another objective of the present invention to increase the speed and lower the cost of performing an MTF measurement.

Apparatus and method for removing offset and shading from a video signal


The invention relates to a device for mounting a telescopic sight onto a weapon. The device is equipped with two mounting feet, which are positioned at a distance from one another and provided with mounting elements for engaging in corresponding receiving openings on the weapon. The aim of the invention is to enable the sight to be positioned accurately without the need for a complex adjustment and fitting process. To achieve this, the mounting elements are configured by clamping bolts, which comprise laterally protruding lugs, are contained in the corresponding mounting feet and can be rotated through a release and locking position. The lugs can be inserted into recesses between inward-facing projecting shoulders of the receiving openings in the release position of the clamping bolts and engage with the underside of the projecting shoulders in the locked position of the bolts.

A mounting device of this type is known from U.S. Pat. No. 4,205,473. In one embodiment disclosed in this publication, a clamping bolt with a downwardly projecting interlocking extension is respectively arranged in two mounting feet that are spaced apart from one another, so that it can be turned between a release position and a locking position. The interlocking extension is realized in the form of a truncated cone with a lateral flattening that is designed for engaging into a slot in a holding plate mounted on the weapon in the release position of the clamping bolt. When the clamping bolt is turned, the interlocking extension engages underneath the holding plate similarly to a quarter-turn fastener. The clamping bolts are rotatably guided in corresponding bores of the mounting feet with the aid of upwardly projecting pins and held in said bores by means of screws.

Device for mounting a telescopic sight on a weapon


A storage device is provided including a support frame having a plurality of elongated support members and a stiffening bracket carried by the support members. An enclosure may be carried by the support frame. The enclosure may be foldable and have a fabric construction and may be detachably attached to the support frame. A plurality of closeable storage compartments may be provided in the enclosure. The storage compartments may contain items such as towels, clothes, shoes, lotion and other items used by a beachgoer or other user, at the beach or other location.

People have enjoyed spending time at the beach for centuries. Beaches provide an opportunity for sunbathing, exercise, fishing, relaxing, surfing, and other activities for millions of people worldwide. As a testimony to their popularity, the beaches around the world are often punctuated with condominiums and other beachfront properties. Furthermore, travelers and tourist may travel domestically or internationally just to visit beaches of their interest and to enjoy a relaxing vacation or off-time experience.
Many beachgoers enjoy spending several hours or an entire day at a time at the beach. In order to spend the time at the beach with relative comfort and entertainment, the beachgoers may bring along numerous supplies such as, but not limited to, towels, chairs, beach umbrellas, coolers, thermoses, lotions, sunglasses, books, cards or other games, as well as cellphones, tablets, headphones, cameras, and other electronic devices. Often, beachgoers may also bring with them food such as fruit, snacks, sandwiches, etc. In addition, they may need a place to store their clothes, shoes, keys, wallet, purse, cap, and/or other everyday items while enjoying a time at the beach.
In practice, it is common for beachgoers to have limited space or area in which to store all the aforementioned items. Furthermore, some items should be kept in the shade as they may deteriorate if left in the sun. In addition, some items may be in greater risk of being stolen by people passing by. For these reasons mainly, beachgoers are often forced to hide items as they possibly can, considering the limited resources available; for instance, objects may be hidden one inside the other (e.g., car keys inside a shoe), one by the other (purse covered by an item of clothing), and/or underneath a towel, to name a few examples. Once items are hidden, beachgoers will typically check every once in a while that the items remain out of sight or in the shade. Having to think of ways to hide items from eyesight or sunlight, and periodically check whether the items remain hidden, may increase stress, and thus adversely affect the relaxation experienced by the beachgoer while spending time at the beach. Furthermore, storing or hiding items one inside the other, etc. may increase the chances of the items becoming inadvertently misplaced and lost, stolen, wet or soiled.
Some solutions have been developed for storing personal items while at the beach. However, these solutions are often bulky and difficult to transport or carry. Other times, beach storage solutions are too small and do not allow for storage of a relatively wide variety of everyday items, food, and other objects such as those mentioned heretofore.
Accordingly, there remains a need for a solution to at least one of the aforementioned problems. For example, there is an established need for a beach storage solution which is suitable to facilitate storage of multiple items such as towels, clothes, shoes, and other items used by a beachgoer.

Storage device for containing personal or other items at the beach or other location


A sheet conveyance apparatus includes a conveyance unit which conveys sheets and a discharge tray which supports the sheets conveyed by the conveyance unit. The discharge tray includes: a first tray which has first, second and third rail sections arranged at different positions respectively in a widthwise direction perpendicular to a conveyance direction and extending respectively in the conveyance direction; and a second tray which is arranged on a lower side of the first tray and which is slidably supported by the first, second, and third rail sections. The first rail section and the third rail section are contrary to each other in relation to the positions in the widthwise direction with respect to the second rail section. The first rail section has a first rib and a first protruding section; and the second rail section has a second rib and a second protruding section.

1. Field of the Invention
The present invention relates to a sheet conveyance apparatus provided with a conveyance unit which conveys sheets, and a discharge tray which supports, in a stacked state, the sheets conveyed by the conveyance unit.
2. Description of the Related Art
An image recording apparatus such as a printer is provided with a sheet conveyance apparatus which conveys sheets such as recording paper to be subjected to the image recording. The sheet conveyance apparatus is provided with a discharge tray which supports the discharged sheets in a stacked state.
The image recording apparatus, which is provided with the sheet conveyance apparatus, is demanded to be small-sized, while it is desired that the sheet having a large size can be conveyed. In order to fulfill the demand as described above, the following construction is known. That is, the paper discharge tray is constructed by a plurality of trays. When the size of the sheet is small, a state is given, in which the plurality of trays are overlapped with each other so that the discharge tray becomes compact. When the size of the sheet is large, the plurality of trays are successively pulled and drawn out so that the discharge tray has an enlarged support surface.
For example, in the well-known recording apparatus, the plurality of trays, which constitute the discharge tray, are connected to one another at both end portions in the widthwise direction of the discharge tray by means of rail structures, and the plurality of trays are slidable. For example, both end portions, of a tray disposed on the upper side, in the widthwise direction and both end portions, of a tray disposed on the lower side, in the widthwise direction constitute the rail structures. The tray disposed on the lower side is supported by the both end portions of the tray disposed on the upper side in a state that the both end portions of the tray disposed on the lower side are engaged with the both end portions of the tray disposed on the upper side respectively. However, in the case of the rail structures as described above, when the weight is applied to the plurality of trays, it is feared that the trays may be warped and the engagements may be broken at the both end portions in the widthwise direction.

Sheet conveyance apparatus, tray unit and discharge tray


The present invention discloses CRC checking ‘N-bit at a time’ of data frames of lengths not necessarily in a multiple of the N-bit. While receiving the data frame, the data frame length is extracted from the protocol header and a misalignment is computed versus the ‘N-bit at a time’ value. Simultaneously, CRC is computed on each received N-bit of the data frame and an FCS register is updated. At each cycle, a checking is performed to know whether the data frame length has been extracted from the protocol header. While the data frame length is not yet known and more bits are left to process, the data frame is continued to be received and computed ‘N-bit at a time’. When the data frame length is known and no more bits are to be processed, the current value of the FCS register is compared to a pre-stored vector corresponding to the misalignment. If a match occurs, checking of the data frame passes and the data frame is accepted. If a match does not occur, checking of the data frame fails and the data frame may be rejected. Therefore, the present invention is capable of computing CRC of a data frame ‘N-bit at a time’ while the data frame length is not yet known.

Frames of data transmitted over telecommunications lines are generally protected with a CRC code. As shown in FIG. 1, frame or message 110 is encoded by transmitting side 100 which adds redundancy under the form of Field Check Sequence (FCS) 105, at the end of frame or message 110, to be transmitted through network 120. Receiving side 130 must then perform a check to accept the frame as valid before any further processing. Protocol frames are generally of variable lengths. This means that there is field 140 somewhere in the protocol header 160 that must be interpreted by the receiver so that the length of current frame 150 is known and the end of frame, and the FCS field, can unambiguously be located in order to be able to perform the checking properly.
CRC checking has long been done '1-bit at a time' with the help of a device referred to as a Linear Feedback Shift Register (LFSR), an example of which is shown in FIG. 2. LFSR is also a convenient means by which the protocols specify how frame encoding and checking must be carried out so as a data frame is encoded by the transmitter and recognized as valid by the receiver according to the protocol specifications. FIG. 2 illustrates an LFSR corresponding to the CRC-32 used by many protocols such as the Adaptation Layer 5 (AAL5) of Asynchronous Transfer Mode (ATM) or Ethernet. This particular LFSR allows the encoding and checking of frames '1-bit at a time' per the following generator polynomial:G(X)=X32+X26+X23+X22+X16+X12+X11+X10+X8+X7+X5+X4+X2+X1+1,
which is the degree 32 generator used by the above protocols for protecting their data transmissions.
When the performance of telecommunications lines used to access a network, such as network 120 shown in FIG. 1, dramatically improves, the simple device of FIG. 2 is no longer capable of handling the increased transmission line speeds. Numerous methods and devices have thus been proposed, and used, to process more bits together. Especially, methods to compute CRC '8-bit (i.e., a byte) at a time' have been devised in order to speed up computation accordingly. One of the earliest reference on a method for computing 8-bit at a time is a paper by A.Perez, "Byte-wise CRC calculations", published in IEEE Micro, June 1983. Because frame lengths are often, if not always, comprised of an integer number of bytes this did not create any difficulty. Either a logic device is fast enough to compute and it is possible to wait until the length of a current frame is extracted before actually starting the computation, or since it is possible to assume that frame lengths are made of an integer number of bytes, computation can start as soon as the first Most Significant Byte (MSB) is received. Then, when length is later extracted from the frame header, computation can be stopped on time to match the actual frame length, on a byte or 8-bit boundary.
However, because telecommunication line performance has continued its dramatic growth, logic designers have now to deal with line speeds in the 10–40 Gbps (Gigabits per second) range. This corresponds, for the lower value, to e.g., an OC-192 Optical carrier of the Synchronous Optical NETwork (SONET) hierarchy, a North American standard, or to the 10 Gbps version of the Ethernet standard. Because the performance of Application Specific Integrated Circuits (ASIC's) or Field Programmable Logic Arrays (FPGA's) that are commonly used to implement the corresponding logic have not seen, by far, their performance increased accordingly, designers have to consider the use of logic devices in which even more bits or bytes have to be processed together, at each device cycle, in an attempt to reach the necessary level of performance. However, if protocol data frames are indeed an integer number of bytes they are not necessarily a multiple of 4 or 8 bytes, which is now the typical number of bytes that must be processed together, to match such line speeds with a cost-performance technology like Complementary Metal Oxide Semiconductor (CMOS) thus avoiding the use of expensive higher performance technologies like the ones based on Gallium Arsenide (GaAs) that would otherwise be required. An example of the problem encountered is shown in FIG. 3 where a 19-byte frame 300 protected e.g., with the 4-byte CRC-32 discussed in FIG. 2, must be handled, for performance reasons, by a device 310 capable of computing 8-byte at a time storing its intermediate results in a 4-byte FCS register 330. Then, computation cannot start until the actual frame length is known because frames are always transmitted MSB first. Hence, if starting right away, as shown in FIG. 3, the result would be wrong because the computation device must be aligned on the last received bit or byte so as the FCS 320 is indeed the true least significant portion of the frame which is clearly not the case here.
In practice, this requires that alignment (i.e., a left justification) be done prior to the beginning of the computation by padding enough null bytes 400 in front of the received frame, as shown in FIG. 4, so that the last cycle of the computation matches exactly with the FCS field 410. In other words, the received frames must be padded with enough front null bytes so as they become a multiple of the number of bits or bytes i.e., 8 bytes in this example, handled at each cycle of the CRC computing device. Like with ordinary numbers, padding 0's in front does not affect the end result of a division which is basically what CRC is doing on the binary string of bits which forms the data frame.
Again, this implies that lengths of frames be known when starting. This goes against the need of having to begin the computation as quickly as possible in order to cope with line speed increases while ASIC and FPGA technologies in use do not enjoy an equivalent improvement of their performances.

Method and apparatus for computing ‘N-bit at a time’ CRC's of data frames of lengths not multiple of N

International Business Machines Corporation


A device for holding a bucket of frozen chum is fabricated primarily out of flexible plastic material that is integrally formed with a toroidal sleeve there around. The toroidal sleeve has a plastic foam floatation element housed therein, so that a frozen bucket of chum that is installed and contained in a cylindrical component of the device is maintained at a right distance below the surface of a body of water in which the device has been deployed. A plurality of holes are provided in components of the device, so that chum matter can pass there through as the frozen chum melts and exits the device into the surrounding body of water to attract fish. The device is also provided with a drawstring that cooperates with an upper edge of the cylindrical containing component to captivate the frozen bucket of chum therein.

1. Field of the Invention
The present invention relates to devices to attract fish.
2. Description of the Prior Art
Numerous innovations for devices and apparatuses to attract fish have been provided in the prior art that will be described. Even though these innovations may be suitable for the specific individual purposes to which they address, however, they differ from the present invention.
A FIRST EXAMPLE, U.S. Pat. No. 2,241,314 to Mohler teaches in a device of the character described, a circular pneumatic float of resilient material, a sack of netting depending from the bottom of the float, and having a mouth extending around the bottom of the float and detachably secured to the latter, and a tethering line attached to said float for anchoring the same, said float having a diametrical slit therein forming an inlet into said sack.
A SECOND EXAMPLE, U.S. Pat. No. 2,580,879 to Belokin, Jr. teaches a collapsible bucket which comprises a foldable, collapsible tubular side portion, a foldable circular bottom portion disposed at one end of said side portion, means for joining said side portion and said bottom in liquid-tight engagement, a collapsible annular, tubular air chamber disposed at the other end of said side portion, the outermost point of said chamber being secured to the inner surface of said side portion, valve means for inflating and deflating said chamber and foldable handle means attached to said side portion.
A THIRD EXAMPLE, U.S. Pat. No. 2,600,826 to Allen teaches a bait container comprising a cylindrical shell having perforations adjacent it upper end; a continuous angle member surrounding said shell and having first and second flanges attached to said shell to form an air chamber, a closure for the upper end of said shell, a receptacle slidably received in said shell, a pair of arms rising from said receptacle, said closure having a pair of openings slidably receiving said arms, and a carrying ball attached to said arms and overlying said closure, said shell being imperforate below said angle member.
A FOURTH EXAMPLE, U.S. Pat. No. 3,499,526 to Willinger teaches this invention is directed to providing a novel fish feeder combination in which the fish food, the food dispenser and instructions therefore are all held in a single storage container. The fish food, preferably freeze dried Tubifex worms, is stored in the lower portion of the two-part container while the food dispenser or feeder and the instructive material describing the use of the novel combination are stored in the upper portion.
A FIFTH EXAMPLE, U.S. Pat. No. 3,717,124 to Jacobs teaches a fish culture cage assembly which includes an annular float ring having a radially inwardly extending flange thereon. The assembly also includes a foraminous, generally cylindrical cage structure, having an open upper end and a closed lower end, detachably depending from said flange, and a lid detachably secured to said float ring and covering the open top of said cage structure. A cylindrical feeding ring may be detachable suspended from projections inside the foraminous cage in the upper portion thereof. The feed ring has a plurality of openings which are substantially smaller than the openings through the cage, the feed ring being open at its upper and lower ends.
A SIXTH EXAMPLE, U.S. Pat. No. 3,974,591 to Ray teaches a perforated chum holder and dispenser is formed in two hingedly connected half sections having snap locking means, whereby the device may be closed around either a fishing line float for top fishing or a line sinker for bottom fishing. The opposite ends of the device are grooved to receive a fishing line or leader with a coacting locking element.
A SEVENTH EXAMPLE, U.S. Pat. No. 4,570,374 to Baxley teaches a floating fish receptacle for retaining caught fish in a live condition under water includes a molded foam, generally cylindrical housing member which includes as part thereof in unitary construction a floatation collar outwardly extending from the outside diameter surface and a pair of baffle members inwardly extending from the inside surface. The baffle members are arranged in an axially (vertically) separated relationship and are radially spaced 180 degrees apart so as to create a zig zag slide action for fish which are dropped through the top opening of the housing. As the fish enters, it strikes one downwardly and inwardly inclined surface of one baffle member and then is transferred to the corresponding surface of the other baffle member and then on through to a mesh bag which is suspended therebelow for retention of the fish. The top opening of the housing is above the water level while the opposite and lower opening of the housing member is below the water level. The mesh bag is secured around this lower opening so as to insure that the mesh bag is below water at all times that fish are stored therein. The baffle members are removable form the main housing as is the mesh bag. Consequently, the main housing member may be used in combination with the mesh bag without the baffle members and the mesh bag may be used independently of the housing member.
AN EIGHTH EXAMPLE, U.S. Pat. No. 4,903,429 to Tetenes teaches a device to attract fish is provided and consists of a bucket held within a net suspended downwardly from a float into a body of water. The bucket holds frozen fish chum so that open top of the bucket is at right distance below water allowing pieces of defrosted fish chum to be dispensed from the bucket and float on the water to attract the fish.

Device for holding a bucket of frozen chum


This disclosure involves stitching event data using identity mappings. An event analytics system generates and stores an event dataset including first event data for a first set of events associated with a user. The first event data includes timestamps and a device identifier. The system identifies second event data for a second event associated with the user. The second event data includes a timestamp, the device identifier, and a user identifier. The system appends the second event data to the event dataset. Based on the second event data, the system generates and stores an identity mapping that maps the device identifier to the user identifier. Asynchronously to generating and storing the event dataset, based on the identity mapping and a predetermined look-back window, the system updates the first event data to include the user identifier.

Collecting and analyzing user data is increasingly popular. A major area of focus is web analytics, which deals with the analysis of data created by website usage. For instance, web analytics can be used to mine visitor traffic data. A variety of visitor traffic data is measured such as what browser is being used, what links on a given web page were selected, whether a product was purchased, and so forth. There are number of web analytics tools presently available that capture and analyze data related to website usage.
Some existing systems "stitch" or "blend" data to tie web traffic data together with other web traffic data. Typically, large amounts of uncorrelated data is collected, and must be analyzed to correlate the data. Correlating the data may involve storing web data in association with an identifier based on a browser or device used. In some existing systems, the web data may be improperly correlated with the identifier because devices can be shared, users often use multiple browsers or devices, and user identifiers are not always cleanly implemented and may have to be retroactively cleaned or corrected.
Accordingly, existing techniques stitch a relatively large amount of data (e.g., collected over the course a window of weeks or months). Over the course of such a window, the data is stored in a form that is not yet useable for analytics purposes. Further, stitching such large amounts of data in batches places a significant drain on computational resources. Thus, existing stitching techniques are computationally inefficient, do not provide results in a timely fashion, and may not provide accurate results.

Stitching event data using identity mappings