A speaker unit includes a woofer having a diaphragm with an ellipse shape sound emitting opening, and a separate speaker having an ellipse shape diaphragm with an area smaller than that of the diaphragm of the woofer, located in front of the diaphragm of the woofer, attached to a center axis of the ellipse shape of the woofer coincident with that of the ellipse shape of the separate speaker, and emitting a sound higher in frequency than that of the woofer.

1. Field of the Invention
The present invention relates to a speaker unit of a composite coaxial type suitable for use as a speaker unit installed in a car, for example.
2. Description of the Related Art.
In the prior art, when a plurality of speakers handling different frequency bands are disposed in a narrow space, the speakers are made as a composite coaxial type of, for example, a two-way system. By arranging the composite coaxial type speaker, as compared with a case where speakers for middle or intermediate frequency sound and low frequency sound are located at different positions in a single cabinet, a sound of intermediate frequency band together with a sound of low frequency band, of course, is emitted from substantially the center position of a speaker for low frequency sound so that the directivity such as a sound image localization or the like is improved.
Further, such a woofer or low frequency sound speaker in which an opening of a cone type diaphragm on its sound emitting side is shaped as an ellipse is used widely. By making the sound emitting opening of the diaphragm as an elliptic shape, it is advantageous when the speaker unit is installed in a limited narrow space such as in a car or the like.
Under the concept mentioned above, in a low frequency sound speaker, or an ellipse type speaker in which a front end, namely a sound emitting opening portion of a cone type diaphragm is made of an ellipse, there is proposed an intermediate or middle frequency sound speaker which is disposed in such a manner that the sound emitting opening portion of the cone shape diaphragm is concentric at the center position of the diaphragm at the front portion of the diaphragm of the low frequency sound speaker.
In case of such a composite coaxial type speaker, there are generated much cross modulation distortions near the cross-over frequency of each of the low and intermediate frequency band speakers and many crests and troughs are caused on a frequency characteristic curve. Hence, it is difficult to obtain a flat characteristic, which lowers the sound quality.
The fact that the sound emitting opening of the low frequency sound speaker is of an ellipse means that the ellipse has a long diameter direction and a short diameter direction.
Since there is coaxially located the intermediate frequency sound speaker, the sound emitting opening of which is of circle, the sound wave emitted forward from the long diameter direction and the sound wave emitted forward from the short diameter direction are reflected on and differected by the rear portion of the circular intermediate frequency sound speaker, namely its frame. As a result, there is caused a phase difference between the sound wave emitted from the long diameter direction and the sound wave emitted from the short diameter direction. This phase difference becomes the distortion which deteriorates the frequency characteristics. Further, the directivities of the sound waves emitted from the long and short diameter directions are different each other and hence the directivity characteristic is deteriorated.
An object of the present invention is to provide a speaker unit which solves the problems mentioned above.
According to an aspect of the present invention, there is proposed a coaxial type speaker, in which a low frequency sound speaker, the sound emitting opening of a diaphragm of which is of an ellipse and at least an intermediate frequency sound speaker, the sound emitting opening of a diaphragm of which is of an ellipse, are arranged coaxially, whereby the difference between directivity characteristics of the sound waves in the long diameter direction and the short diameter direction of the elliptic type low frequency sound speaker is removed and hence the frequency characteristics are improved.
According to another aspect of the present invention, there is provided a composite coaxial speaker unit in which an elliptic type intermediate and high frequency sound speaker is disposed on the center axis of an ellptic type low frequency sound speaker at its front sound emitting opening portion, and the sound emitting opening portion of a diaphragm of the elliptic type low frequency sound speaker and the sound emitting opening portion of a diaphragm of the elliptic type intermediate and high frequency sound speaker are made as a similar figure substantially.
According to the speaker unit of the present invention, since the intermediate and high frequency sound speaker arranged coaxial with the center of the elliptic type low frequency sound speaker is made as an ellipse similar to the low frequency sound speaker, a speaker unit, the frequency characteristics and the directivity characteristics of which are improved and which is suitable to be installed on a car, can be obtained.


A jump rope assembly includes a rope body having two ends each connected with a connecting unit and a handle unit. The rope body has an inner portion provided with a through hole. The connecting unit includes a connecting sleeve mounted on the rope body, a fixing plug inserted into the through hole of the rope body, and a retaining ring mounted in the connecting sleeve and compressing the rope body to press the rope body toward the fixing plug so that the rope body is fixed between the fixing plug and the retaining ring. The handle unit includes a handle having an enlarged end portion mounted in the connecting sleeve, and a locking ring mounted on the enlarged end portion of the handle and locked onto the connecting sleeve.

1. Field of the Invention
The present invention relates to a jumping device and, more particularly, to a jump rope assembly.
2. Description of the Related Art
A conventional jump rope assembly in accordance with the prior art shown in FIGS. 8 and 9 comprises a rope body 40 having two opposite ends each connected with a connecting member 50, a first holding cover 60 and a second holding cover 70. The rope body 40 has a hollow inner portion provided with a through hole 41. The connecting member 50 has a first end provided with a catch portion 51 and a second end provided with a plug 52 which has multiple hooked portions 521. The plug 52 of the connecting member 50 is inserted into the through hole 41 of the rope body 40 until the catch portion 51 of the connecting member 50 abuts the rope body 40 so that the connecting member 50 is locked onto the rope body 40 by the hooked portions 521 of the plug 52. The first holding cover 60 is combined with the second holding cover 70 to cover the connecting member 50 so that the connecting member 50 is clamped between the first holding cover 60 and the second holding cover 70. The first holding cover 60 has a first end provided with at least one first fixing groove 63 to fix the catch portion 51 of the connecting member 50 and a second end provided with at least one slot 61. The first holding cover 60 has a side provided with a first receiving recess 62 to receive the rope body 40. The second holding cover 70 has a first end provided with at least one second fixing groove 73 aligning with the first fixing groove 63 of the first holding cover 60 to fix the catch portion 51 of the connecting member 50 and a second end provided with at least one insert 71 inserted into the slot 61 of the first holding cover 60. The second holding cover 70 has a side provided with a second receiving recess 72 aligning with the first receiving recess 62 of the first holding cover 60 to receive the rope body 40. However, when an external force applied on the rope body 40 is greater than a connecting force between the hooked portions 521 of the plug 52 and the rope body 40, the rope body 40 will be forced to detach the connecting member 50, thereby easily causing danger to the user. In addition, when the rope body 40 is moved, the rope body 40 is twisted by the first holding cover 60 and the second holding cover 70 so that the rope body 40 is easily worn out or broken during a long-term utilization.

Jump rope assembly having enhanced strength


Methods, computer systems, and computer-storage media are provided for augmenting Web-based search results with relevant content received from third-party applications. Each of a plurality of third-party applications is registered to obtain an indication of entity types associated with the each registered third-party application. A user input including at least a search query is received. The search query is communicated to those third-party applications that are identified as being relevant to the search query. Search results that are relevant to the user input are received from the relevant third-party applications and are presented on a results page.

With the proliferation of third-party applications, or apps, on user devices there is a trend towards users fulfilling their domain-specific search needs by utilizing an app specialized for that domain instead of using a Web-based search service. For example, a user searching for nearby restaurants may go directly to his or her URBANSPOON® app to find restaurants and reviews instead of using a search service such as BING®. The result is a diversion of traffic away from Web-based search services.
Further, although search services are effective in crawling and indexing information, the information is currently limited to publicly available information. Information regarding a user's engagement history with a particular app is by and large protected through a user login and is generally not available to search services. As well, content associated with these apps is not available for consumption by Web-based search services. For example, BING® cannot crawl and index a user's EXPEDIA® itinerary. This makes it difficult for search services to fully answer user intent when providing Web-based search results.

This patent is subject to a terminal disclaimer.

Augmenting search results with relevant third-party application content


In an example embodiment, a WDM array includes an optical filter, N common ports, N reflection ports, and N pass ports. The N common ports may be positioned to a first side of the optical filter. N may be greater than or equal to two. The N reflection ports may be positioned to the first side of the optical filter. The N pass ports may be positioned to a second side of the optical filter opposite the first side.

Unless otherwise indicated herein, the materials described herein are not prior art to the claims in the present application and are not admitted to be prior art by inclusion in this section.
Thin film filter-based wavelength division multiplexers (WDMs) are widely used in optical communication systems. Such WDMs may be implemented as a three-port component, including a common port, a reflection port, and a pass port, and may include a thin film filter, a dual fiber collimator, and a single fiber collimator. Some applications may call for multiple WDMs, or a WDM array. Replicating such three-port WDMs as described above for use in a WDM array may be relatively costly and/or may result in a relatively large package.
The subject matter claimed herein is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one exemplary technology area where some embodiments described herein may be practiced.


A restraining device comprises a seat belt and a belt force limiter. The belt force limiter is arranged at a location along the belt and comprises an absorption member which is deformed or destroyed when a predetermined belt tension force is exceeded, whereby a prolongation of the belt section is caused. Further, a holding means is provided that limits the prolongation of said belt section when said absorption means is deformed or destroyed.

The present invention refers to a restraining device comprising a seat belt and a belt force limiter.
In particular in automotive vehicles and aircraft, restraining devices serve to secure the passengers in case of a vehicle crash. In a heavy collision, the tensioning forces of the belt may become strong enough for the belt to cause injuries to the secured passengers. To avoid such injuries, belt force limiters are used that momentarily relax the belt when belt tension force peaks occur, so as to alleviate the tension force peaks. Such belt force limiters are arranged at one belt end and release the belt end when a predetermined belt tension force is exceeded. Thus, the belt force limiter is arranged remote from the belt portion on which the belt force acts on the passenger and at which this force is to be limited. Thereby, the belt force limitation takes effect in the belt portions at a person's body in a reduced manner and only with a delay. Further, belt force limiters are in most cases integrated in a belt winding mechanism, which is technically rather complicated. From German Patent 39 00 066, a belt force limiter is known that has an elastic absorption member. The elastic absorption member responses proportional to the occurring tension forces, which is why it is not suited for exclusively absorbing tension force peaks. From German Patent 39 33 762, a belt force limiter is known in which the absorption member is deformed plastically. Again, the absorption member yields almost proportional to the tension force present so that in case of a delayed occurrence of tension force peaks, the absorption capacity may already be used up. German patent 75 00 059 discloses an absorption member arranged along a belt and bridging a belt loop. Since the belt loop is relatively large, the belt has a large lengthwise yield when the absorption member is destroyed so that a second tension force peak builds up.


A shipping skid, which is used for shipping an article that is mounted on a plurality of feet, includes a base member, a plurality of skid members attached to a bottom surface of the base member, a platform attached to a top surface of the base member via elastic members, and a plurality of mounting plates attached to a top surface of the platform. Each of the mounting plates includes a plurality of clamp channels formed into the top surface thereof, a plurality of receptacles formed into a top surface thereof that are each overlapped by at least one of the clamp channels, and at least one clamp member having engagement prongs and which is removably and selectively attachable into each of the clamp channels. When an article foot is inserted into one of the receptacles and the clamp member is attached into the corresponding clamp channel that overlaps that receptacle, the engagement prongs engage with the foot and secure the foot to the mounting plate. For each mounting plate, at least one of the clamp channels does not overlap the receptacles, and thus when an article foot is inserted into, and the clamp member is attached into, the non-overlapping clamp channel, the engagement prongs engage with the foot and secure the foot to the mounting plate. The plurality of channels and receptacles in a single skid support and secure various sized articles even though such articles can have different foot sizes, spacings and patterns.

Shipping skids are well known in the art, and include a base platform onto which articles to be shipped are placed. Elongated skid members support the platform from underneath so that the prongs of a fork lift can be inserted between the skid members and engage the underside of the platform for picking up and moving the skid. Four side walls and a lid can be attached to the shipping skid to form a shipping container.
Many types of articles to be shipped on skids are mounted on feet. However, when articles are shipped using commercial carriers, they need to be placed on skids so that they can be picked up and moved by fork lifts. To protect the article from moving around on the skid during shipment, some skids have receptacles for the feet. However, since the foot patterns of many similarly sized articles are different (i.e. distance between feet varies for different types of articles), and the foot sizes and lengths vary as well, a separate skid with receptacles having a specific spacing and depth needs to be provided for each type of article foot type, size and spacing.
There is a need for a simplified skid that engages with, secures and support the feet of different types of shipping articles having varying foot types, sizes and spacings.


A method includes scanning a page of a paper document to generate a first digital page image. The method further includes obtaining a second digital page image which corresponds to a second page. The method also includes comparing the first digital page image pixel-by-pixel with the second digital page image to generate a score that indicates a degree to which the first digital page image differs from the second digital page image.

This invention is concerned with providing an automatic comparison of two documents.
When two documents are in the form of electronic text files, they can be compared quite readily by a standard function in conventional word processing programs such as Microsoft Word. However, when both documents are paper hard copies, or one is on paper and the other is an electronic text file, the task of comparing the documents becomes much more difficult. Particular challenges are presented, for example, in the case of verifying that two purported copies of a paper legal document (e.g., a lengthy contract) are in fact identical in text. Conventional practices call for one human being to orally read out from one purported copy, while another human being follows along on the other purported copy. Even when the two individuals are highly skilled paralegals, such a process may be time-consuming, tedious, and prone to error.
Another technique used to compare paper documents entails running both through an optical character recognition (OCR) scan. The two resulting electronic text files may then be compared as if both had been generated from a word processing program. Similarly, if one document is on paper and the other is an electronic text file, the paper document may be OCR scanned to provide a second electronic text file for character-by-character comparison with the text file that was available initially. However, OCR scanning can produce artifacts and discrepancies even where the two paper documents were identical (or where a paper document was printed from the text file to which it is to be compared), so that human review or "clean up" may be required. Also, character-by-character comparison may be impractical as to non-text portions of a document, such as graphs, charts and/or diagrams.

System and methods for comparing documents


A data coding device codes input object color pixel data into coded data. The data coding device includes a parallel/serial converter that converts the object color pixel data composed of parallel data of multiple bits into serial data, a state signal generator that generates a states signal for each bit of the serial data and a prediction device which groups each bit of the serial data based on the state signal, and an arithmetic calculator that converts the color pixel data into coded data based on the data received from the prediction device. A corresponding data decoding device is also disclosed.

1. Field of the Invention
The invention relates to a data coding device and method, and a data decoding device and method; and more particularly it relates to an improved coding and decoding device and methods for color pixel data.
2. Description of Related Art
Since pixel data contain large quantities of information, if the pixel data are processed in its existent state, a large amount of memory capacity is required, the communication rate becomes slower, and impractical. Furthermore, compression technology of the picture image data becomes extremely important. Therefore compression technology for each type of data has been developed and brought into existence from the prior art.
In recent years, as one method of data compression, attention has been paid to technology which makes use of entropy coders and decoders. As one of the entropy coding and decoding technologies, utilization is made for example of arithmetic coding and decoding technology. The concept of this technology is revealed for example in laid open patent publication Sho 62-185413, laid open patent publication 63-74324, and laid open patent publication 63-76525.
FIG. 11 shows a conventional data coding system 50 and a data decoding system 60 which utilizes this type of technology.
The data coding system 50 includes a line buffer 51, and an entropy coder 52. The input color pixel data 100A is input to the line buffer 51 and the entropy coder. The color pixel data 100A, as shown in FIG. 12, in every instance is input as chronological pixel data in a horizontal chronological scan.
The line buffer 51, as a reference pixel generation means, forms reference pixel data an, bn, cn, and dn, relative to the coded object image pixel Xn from the pre-input picture image data 100A. In other words, the line buffer 51 records the continuous record of the n line divisions at the time of scanning. Also, following the inputting of each of the color pixel data 100A of the coded object pixel Xn, the series of pixel data formed from the immediately previous pixel dn, and the peripheral pixels an, bn, and cn are recorded as reference pixel data 110 and output to the entropy coder 52.
The entropy coder 52 is formed for example using the arithmetic coding and (Hoffman) coding methods. Also, the reference pixel data 110 is used as state signals, and the object color pixel data 100A is converted into coded data 200, and output.
The data decoding system 60 is formed to include line buffer 61, and entropy decoder 62. In this instance, the line buffer 61 and the entropy decoder 62 are formed so as to provide a decoded output of the input coded data 200 with entirely the opposite process of the line buffer 51 and the entropy encoder 52 of the data coding system 50.
In this manner, the data coding system 50 and the data decoding system 60 utilize algorithms, which are entirely opposite to each other, to encode the color pixel data 100A into coded data 200, and to decode the coded data 200 into the color pixel data 100B for output. Accordingly, the system can be broadly utilized for each type.
With this type of system, the reference pixel data 110 is utilized by the entropy coder 52, and the entropy decoder 62 state signals. If the number of states, i.e., the number of reference pixels, is great, then the data compression ratio is improved. In other words, when utilization is made of the arithmetic coding method or the Hoffman coding method to realize the entropy coder 52 and the decoder 62, if there is a great bias in the occurrence probability of the 0 and 1 symbols, the data compression ratio can be increased. This is because, with the entropy coding technology, short coding data is (allocated) to the input data having a high occurrence probability, and relatively long coding data is allocated to the input data having low generation probability.
In order to obtain a great bias in the symbol generation (occurrence) probability, according to the prior art, the input data has been classified (grouped) into several states prior to the coding. This is because, without classification (grouping), a good compression ratio cannot be obtained. For example, according to the conventional method shown in FIG. 11, utilization was made of line buffers 51 and 61 to form the reference pixel data. This was input as the state signal used for classification (grouping), into the entropy coder 52 and the entropy decoder 62. Also, the entropy coder 52 and the entropy decoder 62 classify (group) the input data through the utilization of the state signals, thereby accomplishing coding and decoding. In other words, the occurrence probability for each state of the reference pixel data is calculated, and short coding data is given to combinations having high generation (occurrence) probability. By this means, the compression ratio of the data can be increased.
However, with the entropy coder 52 and the entropy decoder 62, it is necessary for the number of coded parameter tables to correspond to the number of states of the reference pixel data. For this reason, to the extent that the number of reference pixels for increasing the compression ratio is great, the coding parameter table is great. Because of this, there is the problem that the entropy coder 52 and the entropy decoder 62 will big, and high in cost.
Assuming that the color pixel data is composed from 4 bit data for each pixel, and that the number of pixels of the reference pixel data 110 is 4, the number of states for coding and decoding parameter tables corresponds to the states of 4 pixels.times.4 bits=16 bit, namely the number of states becomes 2. For this reason, the parameter table must have 65,536 patterns for 2.sup.16 states. As the number of the reference pixels increases by one, the coding and decoding parameter table becomes extremely large, and it is understood that the hardware composing the entropy coder 52 and the entropy decoder 62 become large in scale. Furthermore, also the object pixel is composed of 4 bits, i.e., 4 planes, and a one-bit signal is applied to each plane. As a result, 16 patterns of color values are obtained with 4 bits. Therefore, the parameter table must have a magnitude of 65536.times.16 (see FIG. 13).
To overcome this problem, a method has been proposed for calculating the tendency of the occurrence probability of the color symbols of the object pixels, and for allocating short coded data to a symbol which occurs with a high probability, to improve the compression ratio (laid open patent publication 6-276041). This laid open patent publication also discloses a technology for making the parameter table smaller corresponding to the number of degenerated states compressed in the entropy coder 52 and the entropy decoder 62.
The feature of the system for degenerating the number of states as disclosed in laid open patent publication 6-276041 is shown in FIG. 14. The reference pixel data 110 is input as state signals into the entropy coder 52 and the entropy decoder 62 in the same manner as with the prior art data coder system 50 and the data decoder system 60. The feature is, at the time of its input, the state signal 140 is produced by means of the state degenerator 53, and 63 which degenerates the reference pixel data 110 outputted from the line buffers 51 and 61.
The state degenerators 53 and 63 are designed so as to degenerate the input reference pixel data 110 into the state signal 140 which has a relatively small number of bits, and to output it to the corresponding entropy coder 52 and entropy decoder 62. Furthermore, the predictor 54 and 64, are provided to store, in its memory, a color ranking table (the particulars of which are described in the laid open patent publication 6-276041), which is stored in memory in order to convert the color pixel data into the corresponding color rank, based on the probability of occurrence of the color symbol.
Degeneration is an operation for grouping a number of the original states into less numbers of states. Grouping is executed by selecting combinations of states such that the entropy (the average amount of data to display one symbol) of the post-grouping becomes minimum. Identification bits are assigned to the number of the post-grouping states. This becomes the state signal 140.
In the degeneration table utilized in the state degenerators 53 and 63, the relationship between the combination pattern of the color symbol of the reference pixel data 110 and the degeneration data is defined. There is a method, utilizing this degeneration table, for converting the combination pattern of the color symbol of the input reference pixel data 110 into the degeneration data and output.
FIG. 15 shows an example of a degeneration operation which is accomplished based on this method. In this instance, in order to simplify the explanation, an explanation is provided of an example in which Markov model which is formed from the three pixels A, B, and C, is used as a reference pixel pattern relative to the coded object pixel X, as shown in FIG. 15(A).
As shown in FIG. 15(A), when the reference pixels are formed from the three pixels, the combination pattern of the color symbols become five ways as shown in FIG. 15(B). In other words, the patterns are classified into the five patterns, namely, a pattern in which three of the pixel color symbols entirely conform, three patterns in which two of the three color symbols conform, and a patterning which all of the pixel color symbols are different.
Thus, by using the table shown in FIG. 15(B) as the degeneration tables of the state degenerators 53 and 63, 2.sup.12 patterns of the pixel state, which are all the possible combinations of the three pixels, can be reduced to the five states S1-S5 shown in FIG. 15(B). This allows the reference pixel data 110 to be effectively degenerated, and the number of states of the entropy coder 52 can be greatly reduced.
The general method for arithmetic coding and decoding accomplished in this manner is already described in detail in pgs. 26-44 and pgs. 44-50 of Single Pixel Coding Standard JBIG (International Standard ISO-IEC11544); however, in this instance, it will be simply explained hereafter as the premise of the present invention.
An example of the arithmetic coding type entropy coder 52 utilized in FIG. 11 is shown in FIG. 16. Since the composition of the arithmetic decoder type entropy decoder 62 is substantially the same as the composition of the coder 52, an explanation of it is omitted.
The entropy coder 52 includes the arithmetic calculator 55, and the RAM 56 which functions as a state storage. Within RAM 56, the state parameter table is written which is necessary for determination of the symbol generation (occurrence) number probability essential to coding. The state parameters are specified by the input state signal. To the table of the parameter specified by the state signal, the arithmetic calculator 55 outputs the data at the time of renewal of the calculator parameters as the readout address. Then, the RAM data specified by the readout address is output to the arithmetic calculator 55. The arithmetic calculator 55 converts the input color rank data 120 into coded data 200, on the basis of such input data, and output it.
With such prior art technology, the compression ratio becomes relatively high. However, since the bias of the occurrence probability of the data is not sufficiently taken into account, the compression ratio is fairly low in comparison with the theoretical compression ratio. In addition, since there is substantial degeneration as well, the parameter table also becomes small, and the entropy coder 52 and the entropy decoder 62 are also made smaller. However, only the reference pixels are taken into consideration, and grouping is not conducted to the states of the object pixel for prediction. Because of this, in terms of decoding, time taken for defining the object pixels, i.e., time taken for determining the final value for each plane to which each of the bits of the object pixels is allocated, is not used in the prediction operation, which makes the decoding rate poor.
Additionally, at the time of accomplishing compression or expansion (de-compression), the calculated time according to the RAM or ROM is extended, in addition to the delay in the interconnects, and decoding may not occur on time relative to the input of the data. Because of this, high cost, high speed ROM or RAM becomes necessary, and the entropy decoder 62 also remains in its existent state, in large scale and high cost form.

Device and method for data coding and decoding


A grid-connected inverter for feeding current via a transformer into an electric power grid includes an output bridge arrangement that is actuated via a pulse width modulator, wherein a periodic auxiliary signal is used to determine switching times of the output bridge arrangement. The inverter also includes a synchronization unit for phase synchronization of the auxiliary signal with the electric power grid, wherein the synchronization unit is configured to set a predetermined phase offset (ΔΦ0) of the periodic auxiliary signal with respect to a phase of the electric power grid.

Grid-connected inverters are used in energy supply systems, for example photovoltaic systems and wind energy installations. In grid-connected inverters, a voltage or current profile output at the output of the inverter follows the corresponding profile of the electric power grid. In the energy supply systems, generators, for example photovoltaic modules connected in series and/or parallel, generate a DC voltage, which is supplied to a DC voltage intermediate circuit, possibly after a change in voltage by a step-up converter. Direct current from the DC voltage intermediate circuit is converted into an alternating current that is suitable in terms of its frequency and voltage for feeding into the electric power grid by the inverter. This conversion can take place into a single-phase or multiphase alternating current, in particular three-phase alternating current. In this case, the inverter comprises an output bridge circuit which comprises one or more switching bridges which are generally equipped with power semiconductor switches, depending on the number of phases of the electric power grid into which it is intended to be fed in.
In this case, the power semiconductor switches are actuated in accordance with a specific modulation pattern in such a way that, in combination with filters which are arranged between the inverter and the electric power grid, an output current is generated which is as sinusoidal as possible. In pulse width modulation methods (PWM), which are often used, the power semiconductor switches are switched on and off with a switching frequency that is considerably higher than the frequency of the AC voltage in the electric power grid (for example a switching frequency of 3 to 30 kHz in comparison with a mains frequency of 50 or 60 Hz). Over the course of a period of the system frequency, in this case the ratio between the switch-on time and the switch-off time within a switching frequency period, referred to as the duty factor, is changed in such a way that a profile of the output current as sinusoidal as possible is provided. Known configurations for determining the duty factors or the switching times are, for example, the "sine-triangle modulation method", the "space vector modulation method" (SVM) or modified sine-triangle modulation methods, for example the so-called "third-harmonic sine-triangle modulation method". In these PWM methods, a periodic auxiliary signal, for example a triangular signal in the "sine-triangle modulation method" or a clock signal in the "SVM method" is used for determining the switching times.
Even in the case of relatively complex modulation methods, however, the AC voltage generated is typically not a purely sinusoidal signal, but shows, for example, frequency components at the switching frequency of the modulation method, which are referred to as voltage ripples.
In order to achieve relatively high output currents or powers, in particular in the case of relatively large photovoltaic systems, often two or more inverters are used in parallel. When these inverters are not completely isolated from one another on the output voltage side, compensation currents can occur between the inverters, which result in undesirable additional current loading for the power semiconductor switches of the output bridge circuit of the inverters. Such output currents occur, for example, when inverters are connected to one another both on the DC voltage side via a common intermediate circuit and on the AC voltage side, for example since they are connected directly to the electric power grid without a transformer interposed. On the DC voltage side, coupling can also be provided when no common intermediate circuit is used, but the modules or strings (a series connection of modules) are each grounded with one connection. On the AC voltage side, problematic mutual influencing of two inverters can also be provided via an inductive coupling. In a case of inductive coupling of two inverters, no DC compensation currents flow, but compensation currents with AC components at relatively high frequencies may flow, in particular due to the above-described voltage ripples which are not entirely avoidable during the inversion. Such a coupling can also be observed in installations in which transformers are arranged between the inverters and the electric power grid.
The document DE 10 2008 056 256 A1 shows an inverter arrangement having a plurality of inverters connected in parallel, in which compensation currents between the inverters can be avoided by virtue of the fact that corresponding power semiconductor switches of the individual inverters are actuated at the same time. This is achieved in that one of the inverters, referred to as the master inverter, generates actuation signals for the power semiconductors which are transmitted via corresponding lines to each of the further inverters, which are referred to as slave inverters. However, this method is only practicable in the case of inverters that are arranged physically close to one another.
Document US 2008/0265680 A1 describes an arrangement of a plurality of inverters that are coupled directly with their outputs. The inverters are controlled by PWM methods, wherein the auxiliary signals used in the process are synchronized using a grid voltage. As a result, transmission of actuation signals for the output bridge arrangement of the inverters is not necessary. The electric power grid is used as a synchronization connection. The method is well suitable for directly interconnected inverters. In the case of inverters that are coupled inductively, for example via transformers, however, it has been demonstrated that compensation currents are not completely suppressed.

Grid-connected inverter, inverter arrangement and method for operating an inverter arrangement


A molten fiber material flow is rendered into a plurality of fibers by means of a liquid jet such as water jet in place of a pressurized gas or air. The flow moves downwardly in a vertical direction while the water jet cuts it at an inclined angle. The water jet is formed by a single nozzle or plural nozzles of a flat-jet or round-jet type.

Well-known examples of an inorganic amorphous fiber material are: slags discharged from various glass furnaces and blast furnaces; basic rocks such as basalt; clay minerals such as Kaolin; and mixtures of Bayer process alumina with quartz sand or silica sand.
Such inorganic amorphous fiber materials are discharged continuously from a cupola or electric furnace through its tap hole in the form of a fine flow and then elongated by means of an outer force such as an air jet so as to make fibers. Three typical fiber-producing methods are:
(A) a drawing method by which continuous glass fibers are produced by drawing a fiber material continuously from a nozzle;
(B) a throwing method or a spinning method by which fibers are produced by centrifugal force of a spinner which is a rotation disc for making fibers; and
(C) a blowing method by which fibers are produced by a gas flow such as an air jet at a high speed.
According to a conventional blowing method, a pressurized gas such as air is jetted out through nozzle so as to obtain a flow speed near sonic velocity. A molten fiber material flow is guided into such a gas flow so as to produce fine fibers by means of the gas jet's impact on the molten fiber material flow.
The conventional blowing method has at least three defects.
A first defect is that a very large energy is required in order to compress air for jetting purposes. For example, in case Al.sub.2 O.sub.3 --SiO.sub.2 ceramic fibers are produced, a molten fiber material flow is discharged from a melting furnace at a flow rate of 400 kg/hr, while an air pressure of several kilograms per cm.sup.2 is applied. In order to produce such an air pressure, the air compressor must have about 300 horsepower (255 kw). Therefore, the energy necessary for making fibers is 255 kwh/400 kg=0.64 kwh/kg. In comparison with this energy, the energy necessary for fusing an Al.sub.2 O.sub.3 --SiO.sub.2 material is about 1.8 kwh/kg. Thus, the fiber-making energy is not small.
A second defect of the conventional blowing method is to need a means for collecting fibers. Jet air flowing at a high speed near sonic velocity induces some ambient air into the collecting chamber so that the volume of air to be discharged from the collecting chamber is several times as large as that of the jet air. If the discharging capacity is small, the pressure in the collecting chamber becomes larger than that of the atmosphere so that some fibers may be discharged out of the collecing chamber. In such a case, a large filter device must be provided so as to separate the fibers from the air. Also, a dust collector must be provided so as to keep the ambient atmosphere clean. Therefore, the cost of equipment and operation thereof is large. For example, the electric power required for operating the filter device and the dust collector is 0.5 kwh/kg in total.
A third defect of the conventional blowing method is that the rate of making fibers is low. Some shots is produced in fibers so as to adversely affect the otherwise low heat conductivity of the ceramic fibers functioning as a heat insulating material.

Method and apparatus for producing fibers


This disclosure provides the nucleic acid and protein sequences of novel P450 oxygenases that utilize, at least, taxoid substrates, including taxadiene isomers. The disclosed oxygenases, such as a taxoid 5α-hydroxylase, hydroxylate, at least, the C5 position of a taxoid. Also provided are methods of introducing oxygen at the C5 position of a taxoid and methods of producing the anti-cancer drug, paclitaxel (also known as Taxol™), and other taxoids, such as paclitaxel intermediates.

The complex diterpenoid Taxol™ (Bristol-Myers Squibb; common name paclitaxel) (Wani et al., J. Am. Chem. Soc. 93:2325-2327, 1971) is a potent antimitotic agent with excellent activity against a wide range of cancers, including ovarian and breast cancer (Arbuck and Blaylock, Taxol: Science and Applications, CRC Press, Boca Raton, 397-415, 1995; Holmes et al., ACS Symposium Series 583:31-57, 1995). Paclitaxel was isolated originally from the bark of the Pacific yew (Taxus brevifolia). For a number of years, paclitaxel was obtained exclusively from yew bark, but low yields of this compound from the natural source coupled to the destructive nature of the harvest, prompted new methods of paclitaxel production to be developed.
Total chemical syntheses of paclitaxel have been achieved (for review, see, Kingston et al., Prog. Chem. Org. Nat. Prod. 84:56-225, 2002) but the yields of the drug by this method are too low to be practical. Paclitaxel currently is produced primarily by chemical semisynthesis from advanced taxane metabolites (Holton et al., Taxol: Science and Applications, CRC Press, Boca Raton, 97-121, 1995; Hezari and Croteau, Planta Medica, 63:291-295, 1997) that are isolated from the needles (a renewable resource) of various Taxus speciea. However, at least because of the increasing demand for this drug both for use earlier in the course of cancer intervention and for new therapeutic applications (Goldspiel, Pharmacotherapy 17:110S-125S, 1997), high-yield, cost-effective methods of paclitaxel production continue to be needed. Some have proposed isolating paclitaxel from alternative biological sources, such as the endophytic fungi, Taxomyces andreanae (Stierle et al., J. Nat. Prod 58:1315-1324, 1995), or from Taxus cell cultures (Ketchum et al., Biotechnol. Bioeng. 62:97-105, 1999). However, these methods are also too inefficient to produce sufficient quantities of the drug and have had limited commercial success.
Improving the production yield of paclitaxel from any biological system, whether intact organisms (such as, Taxus plants or paclitaxel-producing fungi) or cell cultures, would be facilitated by a detailed understanding of the paclitaxel biosynthetic pathway. The paclitaxel biosynthetic pathway is complex and believed to involve nearly 20 distinct steps (Floss and Mocek, Taxol: Science and Applications, CRC Press, Boca Raton, 191-208, 1995; and Croteau et al., Curr. Top. Plant Physiol. 15:94-104, 1996). However, relatively few of the enzymatic reactions and intermediates of this complicated pathway have been defined in detail.
The first committed enzyme of the paclitaxel pathway is believed to be taxadiene synthase (Koepp et al., J. Biol. Chem. 270:8686-8690, 1995), which cyclizes the common precursor geranylgeranyl diphosphate (Hefner et al., Arch. Biochem. Biophys. 360:62-74, 1998) to taxadiene (FIG. 1). The cyclized intermediate (i.e., taxa-4(5),11(12)-diene) subsequently undergoes modification involving at least eight oxygenation steps, a formal dehydrogenation, an epoxide rearrangement to an oxetane, and several acylations (Floss and Mocek, Taxol: Science and Applications, CRC Press, Boca Raton, 191-208, 1995; and Croteau et al., Curr. Top. Plant Physiol. 15:94-104, 1996). Taxadiene synthase has been isolated from T. brevifolia and characterized (Hezari et al., Arch. Biochem. Biophys. 322:437444, 1995), the mechanism of action defined (Lin et al., Biochemistry 35:2968-2977, 1996), and the corresponding cDNA clone isolated and expressed (Wildung and Croteau, J. Biol. Chem. 271:9201-9204, 1996).
The second specific step of paclitaxel biosynthesis is believed to be an oxygenation (hydroxylation) reaction that introduces a hydroxyl group to position 5 of taxa-4(5),11(12)-diene to produce taxa-4(20),11(12)-dien-5α-ol. Using a crude Taxus microsome preparation, Hefner et al. (Methods Enzymol. 272:243-250, 1996) demonstrated a microsomal activity that catalyzed the stereospecific hydroxylation of taxa-4(5),11(12)-diene to taxa-4(20),11(12)-dien-5α-ol (with double-bond rearrangement) (Hefner et al., Chem. Biol., 3:479-489, 1996). This microsomal activity was attributed to one or more cytochrome P450 oxygenases (Hefner et al., Chemistry and Biology 3:479-489, 1996). Cytochrome P450 oxygenases are enzymes that have a unique sulfur atom ligated to the heme iron and that, when reduced, form carbon monoxide (CO) complexes. When complexed to carbon monoxide, cytochrome P450 proteins display a major absorption peak (Soret band) near 450 nm.
Taxus microsomal preparations were further shown to catalyze the hydroxylation of taxadiene or taxadien-5α-ol to the level of a pentaol (Hefner et al., Methods Enzymol. 272:243-250, 1996; Lovy Wheeler et al., Arch. Biochem. Biophys., 390:265-278, 2001). These results suggested that the paclitaxel biosynthetic pathway included at least five distinct cytochrome P450 taxoid oxygenases in the early parts of the pathway (Hezari et al., Planta Med. 63:291-295, 1997). Later steps of the paclitaxel biosynthetic pathway are thought to include at least three additional oxygenation steps (C1 and C7 hydroxylations and an epoxidation at C4-C20). These steps also are believed to be catalyzed by cytochrome P450 enzymes, but these reactions reside too far down the pathway to observe in microsomes by current experimental methods (Croteau et al., Curr. Topics Plant Physiol. 15:94-104, 1995; Hezari et al., Planta Med. 63:291-295, 1997 Lovy Wheeler et al., Arch. Biochem. Biophys., 390:265-278, 2001). Since Taxus (yew) plants and cells do not appear to accumulate taxoid metabolites bearing fewer than six oxygen atoms (e.g., hexaol or epoxypentaol) (Kingston et al., Prog. Chem. Org. Nat. Prod. 61:1-206, 1993), such intermediates must be rapidly transformed down the pathway, indicating that the oxygenations (hydroxylations) are relatively slow pathway steps.
Taxus microsome preparations contain hundreds of different proteins, including an estimated 30 to 50 similar cytochrome P450 oxygenases (Hefner et al., Methods Enzymol. 272:243-250, 1996). Biochemical purification of cytochrome P450 enzymes from Taxus microsomes (Hefner et al., Methods Enzymol. 272:243-250, 1996) is not practical, at least, because the numerous P450 cytochrome oxygenases present in this cell fraction have very similar physical properties (Mihaliak et al., Methods Plant Biochem. 9:261-279, 1993). With no useful biochemical means to distinguish among the many microsomal P450 oxygenases, it is not feasible to sufficiently purify any one enzyme to obtain even short peptide sequences. As a result, other methods are needed to isolate and characterize these important enzymes at the molecular level.
Differential display reverse transcription PCR (DD-RT PCR) has been used to isolate methyl jasmonate-induced nucleic acids encoding taxoid oxygenases of the paclitaxel biosynthetic pathway (see, for example, PCT Pub. No. WO01/34780). Several of the encoded oxygenase enzymes have been expressed and functionally characterized (PCT Pub. No. WO01/34780; Schoendorf et al., Proc. Natl. Acad. Sci. USA, 98:1501-1506, 2001; Jennewein et al., Proc. Natl. Acad. Sci. USA, 98:13595-13600, 2001; Jennewein et al., Arch Biochem. Biophys., 413:262-270, 2003). However, transcripts encoding taxoid oxygenases that are not, or only weakly, induced are likely to be missed by the DD-RT PCR technique.
Paclitaxel is an important drug that is not efficiently produced using current methods. Genetic engineering and recombinant technologies offer ways to increase paclitaxel and taxoid yields. To capitalize on these technologies, there is a continuing need to identify and isolate the genes encoding the enzymes of the paclitaxel biosynthetic pathway, including, for example, the numerous oxygenase enzymes, and for methods of using such genes and enzymes to produce paclitaxel and its intermediates.

Washington State University Research Foundation


A system and method is provided for displaying trimmed surfaces on a computer graphics system. The present invention tessellates a three-dimensional surface into triangles and determines whether a trimming curve intersects any triangles. If an intersection occurs, a polygon trimming mask is formed by performing an exclusive OR operation and rendering the polygon into a mask plane. The XOR operation sets the bits in the mask plane corresponding to the trimming mask to logical 1. The rendering hardware then compares the bits in the mask plane with the bits in the frame buffer and draws those pixels which correspond to the bits set to 1 in the mask plane. Since, the trimming mask is a polygon the rendering hardware can perform shading, or lighting calculations using values for points which are contained on the tessellated triangle. In this manner, consistent lighting of a trimmed surface can be achieved. Additionally, the present invention provides for the formation of multiple trimming masks when multiple trimming curves intersect a tessellated triangle. The multiple trimming masks are sequentially XORed into the mask plane and the corresponding pixels are then drawn.

This invention generally relates to the display of parametric surfaces in a computer graphics system. In particular, a trimming operation is implemented wherein a portion of a surface, displayed on a computer graphics system, is subtracted. For example, a scene being displayed may include a sphere, a cylinder, a planar surface and the intersection therebetween. It may be desired to subtract the sphere (or a portion of the sphere) from the scene, such that a shadow, shaded area, or the like may be displayed in place of the sphere.
Generally, non-trimmed parametric surfaces may be rendered on graphics hardware by computing and shading a tessellation area (generally a triangulation) covering the entire surface to be displayed. It should be noted that a triangulated surface shall be used herein to describe any area to be rendered on the display of the computer graphics system. Trimmed surfaces are limited by the intersection of trimming curves therewith, which function to subtract an area, or portion of the surface, for reasons discussed above.
Traditional methods for rendering trimmed surfaces include modifying the tessellation of a surface by introducing surface points along the trimming curves at the point(s) of intersection of the border of the original tessellation triangle. Prior art systems then must compute coordinates, normals and reflected light intensities for each of these additional points. PG,3 Additionally, since the majority of graphics processing systems are optimized for triangles, the relevant portions of the tessellation triangles, near the trimming curve, must be triangulated (FIG. 3). The introduction of these new points results in shading inconsistencies between points on the trimmed surface and the same points on the original non-trimmed surface. Further, processing time is increased for the trimmed surfaces since the coordinates, normals, light intensities and triangulation must occur.
Other conventional systems include using the software of the graphics system to perform trimming, prior to sending the device coordinates to the display hardware, which is a complex and slow solution, that requires a large amount of program memory.
European Patent 0 277 832 performs trimming by using a graphics accelerator which determines where straight line approximating segments of the trimming curves cross subspan boundaries of the tessellated area and changes the vertices of the subspans to trim away portions of the polygon. A data structure is built linking lists of vertex tables that represent the untrimmed polygon and any trimming curves which intersect the polygon.
U.S. Pat. No. 4,914,607 describes a multi-window environment in which the data to be displayed undergoes an exclusive OR operation, bit by bit, with the bit-map data developed in a logical plane.
It can be seen that conventional trimming systems are extremely complex and require a great deal of computing time and overhead. Therefore, it is desirable to have a computer graphics system which is capable of performing a trimming operation that overcomes the drawbacks of prior art systems. In particular a trimming system is desired which: (1) does not require lighting calculations for additional vertices (points) along the trimming curve; (2) avoids triangulation of portions of tessellated triangles near the trimming curve; and (3) provides consistent shading between trimmed and non-trimmed surfaces, i.e. the colors resulting from lighting calculations on a trimmed surface should be identical to the colors resulting from lighting calculations on an identical surface which is not trimmed, for all areas common to both rendered surfaces.

System and method for displaying trimmed surfaces using bitplane masking

International Business Machines Corporation


A telescope eyepiece comprising a series of single-element lenses in a combination that cancels chromatism. A negative field lens produces chromatism that is partly cancelled by an intermediate positive lens. The resulting red and blue focal points behind the intermediate lens are exactly matched by the same focal points for parallel rays assumed to originate from behind the eye lens passing forward, thus creating an achromatic system that cancels the remaining chromatism. An additional one or two intermediate positive lenses may be added to increase the field of view and reduce the curvature of field. The eyepiece designer can set the distortion of the system to zero, or can adjust it in a range from minor pincushion to minor barrel distortion as desired. Spherical aberration is corrected by the selection of curves for the field lens. Astigmatism is corrected by the spacing of the field lens from the next intermediate lens. Different optical glasses are utilized to maximize the apparent field and minimize other aberrations. However, an acceptable 50 degree field-of-view eyepiece can be made using four elements of the same type of optical glass, such as fused silica. In this case, the ultraviolet, visible, and infrared rays are all in focus at once, providing perfect achromatism, as with mirrors.

1. Field of the Invention
This invention is in the field of telescope eyepiece design.
2. Description of Prior Art
The eyepiece of an optical telescope comprises a series of lenses to provide light refraction for magnification and focus. Refractive lenses produce several distortions and aberrations, including color separation, or chromatic aberration. The eye relief and the field of view of an eyepiece are limited by the correlation between the refractive power of the lenses and the magnitude of distortions.
Color distortion is caused by a difference in focal lengths for different colors of light passing through a lens. Higher frequencies of light (blues) are refracted more than lower frequencies (red). Thus, parallel rays of white light passing through a positive (convex) lens will separate into colors, with blues focussed shorter than reds.
Color distortion is counteracted in conventional eyepieces by using two or more lenses of different optical characteristics cemented together. For example, a convex-convex lens of crown glass can be cemented to a piano-concave lens of flint glass. Flint glass has a higher refractive index than crown glass, and much higher dispersion, or color separation. The two lens elements are matched such that the concave lens only partly counters the refraction of the convex lens, but fully counters its dispersion. The result is a net positive combined lens with no chromatism, called an achromatic doublet. Sometimes more than two lenses are cemented together to optimize the design for a particular use.
Numerous telescope eyepiece designs are available, including Huygens, Ramsden, Tolles, Hastings, Steinheil, Kellner, Orthoscopic, Plossl, Erfle, Aspheric, Bertele, Tele Vue Wide-Angle, Nagler types 1 and 2, and RKE. The simpler ones have a small field of view and noticeable aberrations, possibly including chromatism. The best-performing designs use achromatic doublets to correct many of these faults, but are expensive and often have faults anyway.
A characteristic of some eyepieces is a kidney-bean-shaped black cloud that appears in the image unless the eye is located precisely at the eyepiece. For example, the Nagler type 1 eyepiece has an 82-degree field of view, but exhibits "kidney bean" aberration, and it uses 7 lens elements with three doublets. The Nagler Type 2 eyepiece reduces this problem, but requires three doublets and a total of 8 lens elements. The Nagler eyepieces also have pincushion distortion.
Curvature of field is a substantial disadvantage for older viewers, since eye accommodation lessens with age due to hardening of the lens in the eye. Curvature of field in an eyepiece thus causes the edge of the field to be out of focus for an older person, limiting the useful field without an eyepiece focus adjustment. A young person's eye can easily change diopter enough to quickly adjust focus as the view goes from center to edge. Thus, a young viewer is hardly aware of the eyepiece curvature of field. Astigmatism toward the edge of the field reduces resolution. Many people, especially beginners, are content to live with off-axis aberrations like curvature and astigmatism, especially if the eyepiece is a bargain in price. For a sharper image, one can center the object in the eyepiece.
Inadequate eye relief (distance of the eye from the lens) is a problem on some eyepieces, allowing the eyelashes to brush the eye lens, coating it with body oils, which quickly reduces resolution. A Kellner has very good color correction. If the elements are multicoated, it is probably as good optically as an Orthoscopic, but the eye relief is small. One sweep of the eyelashes and the crispness of view is lost. This is why many astronomers prefer Orthoscopics, which allow viewing all night without having to clean the eyepiece. However, the apparent field of view is only about 40 degrees in both the Kellner and Orthoscopics, so they are best suited for planetary viewing. The RKE (Edmund) is a design based on the Kellner with better eye relief, but it still has a small field. A small field can be an advantage for planetary viewing because extraneous items are automatically eliminated. However, for general viewing, once a person looks through a good wide-field eyepiece, he will probably be dissatisfied with anything under about a 60-degree field. Narrower fields give the impression of looking through a tunnel. It is better to have a good wide-field eyepiece with an adjustable aperture which can be reduced to concentrate on one object for a period of time.
The Kellner 3-element eyepiece (with one doublet) has good color correction and fair edge sharpness, but has appreciable astigmatism and curvature of field with only a 40 to 45 degree field width. The Orthoscopic 4-element eyepiece (with one triplet) has high image contrast and very good color correction, but has appreciable field curvature and astigmatism at the edge of a 40 to 45 degree field. The Plossl 4 to 7 element eyepiece has good image sharpness across 36 to 52 degrees, and perfect achromatism, but has noticeable astigmatism starting 15 degrees from the center of the field, and it uses doublets. The Pentax XL, Meade Super WideAngle, and TeleVue Panoptic 5 to 8 element widefields have 60 to 70 degree fields and excellent image sharpness and contrast. The Naglers and Meade Ultra Wide Angle 7 or 8 element have fields of 80 degrees or more. However these wide and ultrawide field eyepieces use doublets, usually have noticeable distortion, some kidney bean aberration, and their resolution is noticeably reduced below f/4.5 or f/4. They are also very heavy, and may not be capable of incorporating the atmospheric dispersion correction of U.S. Pat. No. 5,696,635, but may require a different more costly approach.
Wide-field eyepieces are becoming more popular. If it were not for the cost, these are what most viewers would probably choose, not only for the wide field, but because the image looks sharp and more natural over the whole field. Inexpensive eyepieces often have fields effectively narrowed by aberrations toward the edges, such as field curvature, distortion, astigmatism, and excessive color. Such eyepieces may only provide 25-30 degrees of useable field width, although additional unusable field width is sometimes provided for exaggerated advertising claims. However, present widefields are excessively large, heavy, and costly.
Achromatic doublets are more expensive than simple lenses, due to the additional lens elements, the design work and precision required to match a common surface, and the assembly steps of gluing them together. They are also heavier than simple lenses. It would be an advantage to eliminate them if chromatism could be avoided while providing high refractive control, a wide field of view, and avoiding other distortions and aberrations.

Achromatic telescope eyepiece without doublets


An outlet (10) for unloading a pulverulent lading comprises an outlet body secured to the lower reaches of a railcar in communication with the lading carried by the railcar. The outlet body has an opening therein through which the lading is unloaded. A valve mechanism (30, 32) is movable between a closed and an open position for lading discharge. A valve operator (56, 58) is used to open and close the valves. A sampling port (60) is formed in the valve mechanism. Movement of the valve from its closed position to a sampling position intermediate its closed and open positions, allows a small amount of lading to be discharged only from the sampling port so a sample of the lading may be readily taken. At this time, the valve member blocks the remainder of the outlet so a lading discharge tube (26) cannot be overfilled with lading, and no spillage of lading onto a right of way can occur.

This invention relates to an outlet conventionally used on railcars for unloading a pulverant lading from within the car by gravity, a pneumatic conveying system, or the like. More specifically, this invention relates to readily taking a sample of the lading from the outlet without having to draw a large sample and in such a manner that the outlet may be readily and reliably closed after the sample is taken.
Conventionally, railcars, usually covered hopper cars, carry a variety of dry pulverant ladings. The lading may be powders such as cement or talc, or granular ladings such as grain or plastic pellets, or other dry, flowable pulverulent ladings. The covered hopper car is provided with hoppers that allow the lading to flow downwardly by gravity within the car toward one or more outlets at the bottom of the car. With some ladings, such as grain, the lading may be readily unloaded from the car merely by opening a slide gate at the bottom of the hopper and allowing the grain to flow by gravity through an open outlet into a grain transport system intake located below the railcar. However, with other ladings, such as with cement or plastic pellets, the shipper usually does not have an unloading transport system built into his siding. Here, it is generally intended that the lading not only be unloaded from the car, but also conveyed to a use or storage site some distance from where the railcar is unloaded. In these instances, it is typical for the lading to be unloaded using a so-called pneumatic unloading outlet.
Generally, a pneumatic unloading outlet includes an unloader body adapted to be secured to the bottom reaches of the downwardly sloping hopper sheets of a covered hopper car or the like. The outlet body has side sheets converging downwardly and inwardly to define an elongate discharge opening which typically extends laterally (from side-to-side) of the railcar. A product tube is positioned below the opening and is open to the discharge outlet to receive lading discharged through the opening. Typically, the outlet includes a valve selectively operable by a train attendant to regulate flow of lading from the discharge outlet into the product tube. One end of the product tube is open to the atmosphere and the other end is connected, via a hose, to a vacuum source which draws air into the open end of the product tube and through the product tube. As the air moves through the product tube, lading discharged into the product tube is entrained with the air and conveyed with the air to a storage receptacle or bin remote from the car.
A variety of railcar outlet types are known. For example, for direct gravity discharge of a lading, such as grain, a slide gate, such as is shown in U.S. Pat. No. 3,397,654, is often used. Such slide gates are relatively large plates that close off the product discharge opening in the discharge hopper and which are forcibly moved between a closed position and an open position by a gate opening and closing mechanism such as a rack and pinion drive.
Various designs for pneumatic outlets are known. A first type of pneumatic outlet uses a so-called rotating tube valve member (actually a tube with one side cut away) which is disposed within a product discharge slot of the outlet. The tube is rotatable about an axis parallel to the elongate discharge opening between a closed position (in which the cylindrical surface of the valve member blocks the flow of the lading) and an open position (in which the edge of the cut away section of the valve member rotates clear of the edge of the discharge opening and permits lading discharge into the product discharge opening). Such rotating tube pneumatic outlets are described in the co-assigned U.S. Pat. No. 3,778,114. As shown in this patent, an outlet typically has two (2) independently operable valve members, one disposed in a first half of the discharge opening and one disposed in the other half thereof. The outlet is provided with a set of two operating handles on each side of the outlet which may be operated by a train attendant to unload a lading from the railcar via the outlet. A first set of handles operates the valve member on the near side of the outlet and the other set operates the valve member on the far side of the outlet. Also as shown in this patent, a series of enlarged, spaced teeth is provided along one marginal edge of the valve member with indentations between the teeth controlling the discharge of the lading. A similar valve member construction is shown in co-assigned U.S. Pat. No. 3,194,420.
Another style of pneumatic outlet is shown in co-assigned U.S. Pat. No. 4,114,785 in which the near and far side valve members are rotary flapper gates mounted for rotation about an axis disposed generally parallel to the elongate discharge opening within and above the discharge opening for movement between a closed and an open position.
Still another style of pneumatic outlet is described in U.S. Pat. No. 4,411,560 in which a so-called rotating bar control valve is used. In a rotating bar outlet, the valve member is an enlarged diameter bar disposed within the discharge opening of the outlet for rotation about an axis parallel to, and somewhat below, the axis of the opening. With the bar valve in it closed position, the outer periphery of the bar spans across the outlet opening to block flow of lading from the discharge outlet. The valve is rotated from its closed position to bring elongated recesses in the valve member into communication with lading above the discharge outlet, and with a product discharge tube, so at least part of the lading is free to flow through the discharge outlet into the product tube.
Other pneumatic outlets are known which use horizontal slide gates movable by a mechanical operating mechanism between their closed and open positions to respectively block the flow and to permit the flow of lading from the discharge outlet into a product tube therebelow. Such slide gates described are in U.S. Pat. Nos. 4,695,207 and 5,000,358.
It is often desirable for a train attendant to take a sample of the lading in the railcar prior to unloading the lading. This can be accomplished by opening one of the hatches in the roof of the car and withdrawing a sample. However, this practice is discouraged because, first, it requires the attendant to climb onto the roof of the car and, secondly, by opening the hatch, there is a chance of contaminating the lading.
Train attendants have also taken lading samples by removing at least one of the end caps installed on the ends of the product discharge tube of a pneumatic outlet, and then operating the valve operating handles to partially open one of the valve members. This allows some of the lading to discharge from the outlet into the product discharge tube. Of course, once a small quantity of the lading has been so discharged, it is necessary for the attendant to close the valve to prevent continued flow of the lading into the product discharge tube. With certain types of pneumatic outlets, the train attendant must remove both the near and far side end caps, because these end caps are designed to prevent operations of either of the operating handles when either end cap is installed. Further, once a valve member is partially opened to withdraw the sample, it is often difficult to fully re-close the valve member. If the valve member does not fully close, lading continues to be discharged from the discharge opening of the outlet and this may result in the product tube becoming filled with lading. Of course, if the product tube becomes filled with the lading, air cannot be drawn through the product tube, thus preventing pneumatic conveying of lading from the railcar.
In an effort to overcome the problems of withdrawing a sample of lading from the outlet of a railcar, special sampling features have been incorporated into the outlets. As described in co-assigned U.S. Pat. No. 4,151,935, an arrangement was provided in a rotary flapper valve pneumatic outlet so the rotary valve member on the near side of the outlet may be moved from its fully closed position to a sampling or partially open position thereby allowing a sample of the lading to fall into the product tube. Because the end cap on the far side of the outlet need not be removed to permit the near side operating handle to be moved to the sampling position, the near valve member side could not be moved to its fully open position thus preventing the inadvertent full opening of the near side outlet valve. While this did facilitate sampling of lading via the outlet, movement of the near side outlet valve to the sampling position did release lading along the full length of the near side outlet valve (a length of approximately 31 inches) into the product discharge tube. Depending on the lading, its release, even in the partially open sampling position, may result in filling of the product discharge tube. Also, the quantity of lading released into the product discharge tube is often significantly greater than is required for a sample. The quantity of lading thus remaining in the product discharge tube now must be cleaned out. Often, it is discharged onto the railroad right of way beneath the railcar. If a toxic or hazardous lading was being sampled, the result was an environmental hazardous product spill. Still further, with such prior sampling outlets, because the entire near side outlet valve was moved to the partially open sampling position, some ladings (particularly large granular ladings) may become jammed between the edge of the outlet defining the product discharge opening and the valve member. This makes it difficult or impossible to fully re-close the outlet valve. If the outlet valve is not fully closed after taking a sample, subsequent shipping of the lading in the railcar may result in leakage of lading into the product tube so when it is desired to unload the lading, the product discharge tube would be filled with lading, thus preventing pneumatic unloading until the product discharge tube was cleaned out.
Accordingly, there has been a long-standing need for a sampling system usable with all types of outlets, which does not require opening the full length of the outlet valve to take a sample, which does not release unduly large quantities of the lading, and which does not become jammed with the lading so a valve member can be fully re-closed after a sample has been taken.


A tabletop grill generally includes a housing, a heating element disposed within the housing, and a grill plate configured to be removably mounted on the housing. The grill plate and the housing are magnetically connectable to retain the grill plate on the housing.

The present invention relates generally to heating appliances and, more particularly, to a tabletop grill for use in heating a food product.
Many conventional tabletop grills have an upper housing and a lower housing that are connected together via a hinge in a clamshell-type configuration. A grill plate covers each of the housings, and a heating element is disposed within each of the housings for heating the grill plate and, therefore, a food product contacting the grill plate. In some conventional grills, the plates are removable from their associated housings for cleaning. However, the plates are typically removable using a latch mechanism that is susceptible to malfunction or breakage. It would be useful, therefore, to provide a tabletop grill with a simpler and more reliable device for removably mounting the grill plates on the housings.


An apparatus comprising a number of cross-coupled charge pump stages configured to generate an output voltage in response to (i) a supply voltage, (ii) a first signal, and (iii) a second signal, where the output voltage has a greater magnitude than the supply voltage.

The present invention relates to a method and/or architecture for charge pumps generally and, more particularly, to a method and/or architecture for low voltage supply high efficiency cross-coupled high voltage charge pumps.
Charge pumps are circuits that pump charge into capacitors to develop an output voltage higher than the supply voltage. High voltage charge pumps provide positive or negative high voltage to program/erase programmable elements such as EEPROM and flash memory, power solid-state particle detectors and photo-multipliers, drive analog switches, etc. Multiple charge pump circuits can be implemented serially to increase the voltages provided. Conventional charge pump circuits include a number of serially connected stages. The stages contain a diode (or transistor configured as a diode) and a capacitor. The stages are driven by a clock signal.
Referring to FIG. 1a, a diagram of a circuit 10 illustrating a conventional charge pump is shown. The circuit 10 illustrates a so-called Dickson charge pump circuit (see J. F. Dickson, xe2x80x9cOn-Chip High-Voltage Generation in MNOS Integrated Circuits Using an Improved Voltage Multiplier Techniquexe2x80x9d, IEEE J. of Solid-state Cir., vol SC-11, No. 3, June, 1976, pp. 374-378, which is hereby incorporated by reference in its entirety). The circuit 10 includes a number of stages 12a-12n. Each stage 12 contains a diode connected transistor 14 and a capacitor 16.
The circuit 10 can provide a supply voltage minus threshold voltage (Vccxe2x88x92Vt) increase at each stage. The output voltage Vpp of the circuit 10 can be Vpp=(Vccxe2x88x92Vt)*n+Vcc. However, the amplitude of clock pulses xcfx86a and xcfx86b, pump capacitance (Cp), stage parasitic capacitance (Cs), and load current (Io) are factors that can limit the voltage gain achieved at each pump stage.
For charge to be passed fully from a lower stage to a higher stage, the increase in voltage for the stage xcex94Vstage must be greater than the transistor threshold voltage Vt. The circuit 10 has a number of disadvantages. For example, (i) the diode drop reduces efficiency, (ii) the breakdown voltage of the transistors must increase as charge pump output voltage increases, (iii) extra stages are required due to low efficiency, (iv) an output voltage at least one Vt above the desired output voltage must be developed, and (v) the circuit 10 does not work well at low supply voltage levels.
Referring to FIG. 1b, a diagram of a circuit 20 illustrating another conventional charge pump is shown. A description of the circuit 20 can be found in Jieh-Tsong Wu and Kuen-Long Chang, xe2x80x9cMOS Charge Pumps for Low-Voltage Operationxe2x80x9d, IEEE J. of Solid-state Cir., Vol. 33, No. 4, April, 1998, pp 592-597, which is hereby incorporated by reference in its entirety. The circuit 20 is implemented similarly to the circuit 10 of FIG. 1a. However, to improve low supply voltage performance, each stage 22 of the circuit 20 has an additional transistor 28. The circuit 20 is more efficient than the circuit 10 and eliminates the voltage threshold Vt drop. However, the circuit 20 has disadvantages in that (i) the charge can flow backwards when the clock signals xcfx86a and xcfx86b transition low at each corresponding stage and (ii) the circuit 20 must develop an output voltage that is at least one Vt higher than the required output voltage Vpp.
Referring to FIG. 1c, a diagram of a circuit 30 illustrating another conventional charge pump circuit is shown. A description of the circuit 30 can be found in Jieh-Tsong Wu and Kuen-Long Chang, xe2x80x9cLow Supply Voltage MOS Charge Pumpsxe2x80x9d, 1997 Symposium on VLSI Circuits Digest of Technical Papers, pp 81-82, which is hereby incorporated by reference in its entirety. In order to eliminate the charge backflow problem of the circuit 20 of FIG. 1b, a charge transfer switch circuit 40 is added at each stage 32a-32(nxe2x88x921). The circuit 30 has an advantage when compared to the circuit 20 that charge is always pumped forward. However, the circuit 30 has the disadvantages of (i) an output voltage that must be at least one Vt above the desired output voltage and (ii) the transistors and capacitors at the stages 32nxe2x88x921 and 32n must have a high breakdown voltage (breakdown voltage=Vpp+Vt where Vt can be as high as 3V).
It would be desirable to have a charge pump circuit that can efficiently develop a high positive or negative output voltage from a low input voltage without requiring higher breakdown voltage transistors.
The present invention concerns an apparatus comprising a number of cross-coupled charge pump stages configured to generate an output voltage in response to (i) a supply voltage, (ii) a first signal, and (iii) a second signal, where the output voltage has a greater magnitude than the supply voltage.
The objects, features and advantages of the present invention include providing a method and/or architecture for implementing a low voltage supply higher efficiency cross-coupled high voltage charge pump that may (i) have improved efficiency, (ii) have reduced diode drop, (iii) perform well at low supply voltages, (iv) reduce the need for higher breakdown voltage transistors, (v) require little extra die area, and/or (vi) be easily implemented.

Low voltage supply higher efficiency cross-coupled high voltage charge pumps


A wheel chock for restraining movement of a vehicle tire on a supporting grating during transit includes a base, a grate lock mechanism for locking the base to the grating, and a ramp on the base for engagement with a circumference of a vehicle tire. A strap connected with the base is extensible around the vehicle tire to help restrain movement of the tire on the grating. The chock includes a retractor for retracting the strap and for taking up slack that forms in the strap during transit.

The invention relates to a wheel chock, used for example in helping to hold an automobile in position in a railroad car during transportation of the automobile by train (in transit). The invention also relates to a wall mount for a wheel chock, and to a system that includes both the wall mount and the wheel chock.
U.S. Pat. Nos. 5,312,213 and 5,302,063 disclose a wheel chock system for such an application. The system resists fore-and-aft vehicle movement with angled ramps, and also resists lateral vehicle movement, but does not prevent upward movement of the vehicle. Thus, when a significant fore-and-aft impact force is applied, for example when two railroad cars are being coupled, the automobiles can ride up over the ramps, causing damage. The disclosure of these two patents is incorporated by reference.


An equine ankle brace system. The system includes a brace and at least one treatment insert arranged to be releasably secured within the brace. The brace comprises a panel of a resilient thermally insulating, heat retaining, e.g., neoprene rubber, material, having a cup-shaped bottom portion for enabling the panel to be wrapped around the ankle to readily conform to it. The panel has an inner surface and an outer surface, a pair of front marginal edges and three groups of releasably securable straps coupled to the panel to enable the panel to be wrapped about the horse's ankle in close conformance therewith and to be held in place thereon against accidental disconnection. One group of straps is secured adjacent one of the front edges of the panel while the other group of straps is secured adjacent the other of the front edges and is arranged to overlap the one group of straps. The third group is connected to the panel adjacent the cup shaped portion to provide fetlock support. The system also includes plural treatment inserts, each one being of a different material depending upon the desired result to be provided thereby. Each embodiment the treatment insert comprises a material arranged to produce a beneficial effect, e.g., shock absorption, on the horse's ankle and has a releasable securable connector, e.g., one component of a hook and loop fastening system, fixedly secured to it to releasably engage a cooperating connector secured to the panel to mount the insert on the brace and to hold it in place.

This invention relates generally to ankle braces and more particularly to ankle braces for horses.
Horses, particularly those involved in athletic activities, such as running, jumping, etc., frequently suffer from a variety of ailments to their ankles and the muscles and tendons associated therewith. These ailments can vary from simple tendonitis to severe joint degeneration.
Several United States Letters Patents have been issued disclosing various braces for use on the ankles of horses to provide bracing and/or other beneficial effects to the ankle and associated anatomical structures. Those patents are: U. S. Pat. No. 2,512,925(Eggeman), 2,937,487 (Dever), 3,193,984 (Schubert), 4,099,269 (Porner), 4,538,602 (Shapiro), 5,115,627 (Scott), 5,152,285 (Gnegy), 5,363,632 (Armato) and 5,579,627 (Vogt). Moreover, the braces of the Scott and Vogt patents are commercially available.
While the foregoing prior art equine ankle braces may be generally suitable for their intended purposes, they never the less leave something to be desired from one or more of the standpoints of adaptability for various applications, effectiveness, ease of mounting and dismounting, ease of use, ease of adjustment, resistance to accidental disconnection or loosening, and customization of the brace for a particular therapy desired.