An apparatus and method for aligning an irregularly shaped object with a contact mask is disclosed. The apparatus includes a means for holding the irregularly shaped object, a means for holding a contact mask, a means for keeping the object and contact mask apart during alignment, means for optically aligning the contact mask to the object, and a means to bring the cube and object together once aligned. A conventional mask alignment tool has been modified to support a clamping fixture which holds the object in a fixed position. It includes a wafer sized disk made of deformable material which permits the edges of the disk to be in contact with the mask, yet when deflected by vacuum pressure will keep the surface of the object away from the contact mask assembly. Upon proper alignment, the vacuum is released and the deformable disk allows the object to cone in contact with the contact mask. In the method of the invention, the process steps include holding an object and contact mask in a spaced relationship from each other, optically aligning the object and contact mask through the holes in the contact mask, and bringing the object and contact mask together once aligned.

1. Field of the Invention
This invention relates to a method and apparatus for aligning a contact mask with an irregularly shaped object intolerant of contact during alignment. In particular, an apparatus and process for aligning a contact mask with a semiconductor memory cube is described.
2. Background Information
Computer memories have achieved greater and greater density as the computer industry has matured. Traditionally, these memories are created on a semiconductor wafer and then diced into individual memory chips. Input/Output (I/O) connections between chip and package are made using wire bond or solder ball technologies or other well-known processes. A description of solder ball technology can found in U.S. Pat. Nos. 3,429,040 and 3,401,126 which are assigned to the Assignee of this invention.
To achieve even greater packaging density for semiconductor components, it is known that individual chips can be laminated together. Additional information on this technology can be found in IBM Technical Disclosure Bulletin, Vol. 18, NO. 10, March 1976, pp. 3239-3242 and in U.S. Pat. Nos. 4,551,629 and 4,646,128. With this arrangement, it is no longer possible to make I/O connections on the top surfaces of the chips because they are no longer accessible. Therefore, it is required to make I/O connections along the exposed perimeters of the individual chips.
FIG. 1 shows a diagram of a memory cube 10 made up of individual chips 12 laminated together. One surface of the cube 14, which is made up of the edge surfaces of a common side of the chips 12, serves as the I/O surface for the package. When depositing the metallurgy for I/O connection using solder ball technology, there is one step in the process where a contact mask 20 as shown in FIG. 2 must be aligned with the pattern of connection sites on the memory cube without any touching of the surface. Then, the contact mask is clamped to the cube in a fixture for further processing. The surface of the memory cube is absolutely intolerant of any sliding friction during this alignment and clamping procedure, since the metal previously deposited could be damaged.
Conventional mask alignment tools cannot meet this requirement since they allow a contact mask to slide on top of a wafer or other object in process during the alignment. Additionally, conventional tooling is not adapted to handle non-wafer shaped structure, such as a cube. Therefore, it is desirable to have an apparatus and method for aligning a contact mask and a non-wafer shaped structure, such as a memory cube, without the two touching until alignment is completed. At the point, contact is permitted and the objects can be clamped together for further processing steps, such as metal deposition.

Mask alignment system for components with extremely sensitive surfaces


The operational state transitions and events of an RF transmitter having a plurality of operational states are monitored and recorded. A plurality of ports are provided that each receive an indication of an occurrence of an event that can cause a transition from one state to another of the plurality of states. A transition status memory stores transition status data representing the status of each associated state. A micro-controller is programmed so that it determines, for each state, from the indications whether a state transition has occurred and, if so, it causes an appropriate change in the associated transition state data stored in the memory.

RF transmitters include AM, FM and TV transmitters. Such transmitters typically include a group of RF amplifiers and power supplies with a plurality of components. Such a transmitter has different operational modes. Some systems have a very sophisticated turn-on and turn-off process or sequence. The sequence may include a dozen or more steps or stages and the operation will be switched from one state to another during the process. The timing between the various states of operation may be very critical; otherwise it may cause damage to the system. A typical IOT (Inductive Output Tube) transmitter, for example, may include a plurality of states such as four main states and each main state may have several sub-states such as fourteen sub-states. These sub-states operate the on, off or standby processes as the system advances from one state to another in precise timing. The processes may be interrupted by an external event such as a command or one of many possible faults.
It is desirable that all state transition and mode switching be recorded along with the time of happening for system operation diagnosing and monitoring. All commands or faulty events that happen during the operation to cause system state change should be recorded with the time of occurrence. The recording (or logging) could record operator activities on the system operation, such as issuing a command to turn on or off the system or the subsystem or to raise or lower the power or to switch exciters.

Operational state transition and event logging system for an RF transmitter


A method for manufacturing a solid electrolytic capacitor device is disclosed. The solid electrolytic capacitor device comprises a package substrate and a capacitor element which is mounted on the package substrate. The package substrate comprises an outer anode electrode, an outer cathode electrode, an inner anode electrode and an inner cathode electrode. The outer anode electrode is electrically connected to the inner anode electrode. The outer cathode electrode is electrically connected to the inner cathode electrode. The capacitor element comprises a capacitor body and an anode lead portion which extends from the capacitor body. The capacitor body has a surface at least one part of which is provided with a cathode portion. The method comprises: forming the anode lead portion; forming the cathode portion after the formation of the anode lead portion; and connecting the anode lead portion and the cathode portion to the inner anode electrode and the inner cathode electrode, respectively.

This invention relates to a solid electrolytic capacitor device and a method for manufacturing the same.
There have been proposed various kinds of solid electrolytic capacitor devices each of which comprises an aluminum anode member. For example, JP-A H09(1997)-283376 or JP-A 2001-267181 discloses an aluminum solid electrolytic capacitor device, the contents of those documents being incorporated herein by reference in their entireties.
The solid electrolytic capacitor device of JP-A 2001-267181 comprises a package substrate and a capacitor element mounted on the package substrate. The capacitor element comprises a capacitor body and an anode lead portion which extends from the capacitor body. The capacitor body has a surface at least one part of which is provided with a cathode portion. However, the capacitor body of the disclosed solid electrolytic capacitor device may have defects.

Solid electrolytic capacitor device and manufacturing method of the same


A testing apparatus for electronic components comprises a mounting block and a plurality of contact strips arranged on the mounting block. The contact strips are configured such that electrical leads of an electronic component are operative to press against and bend the contact strips in a biasing direction to ensure good contact between the electrical leads and the contact strips during testing of the electronic component. Further, a preload block located on the mounting block is operative to contact and apply a pre-stress force onto the contact strips in the biasing direction prior to contact between the electrical leads and the contact strips.

Conventionally, a contacting device comprises a plurality of contact strips, and a mounting block for mounting the contact strips. In order to perform testing on an electronic component, the component being tested is positioned onto the contact strips so that electrical leads of the component make electrical contact with the contact strips. Upon electrical contact being made, the electronic component is then generally driven further in the direction of the contact strips to bend the contact strips and to ensure that there is good contact between the electrical leads of the component and the contact strips.
This is because whether the electrical contact is good enough to ensure testing reliability is determined by the contact resistance between the electrical leads and the contact strips. For the purpose of ensuring that there is good contact, the contact pressure between the electrical leads on the electronic component and the contact strips has to be greater than a certain predetermined level, which level usually depends on the materials from which the electrical leads and contact strips are made of.
In turn, in order to create sufficient contact pressure, the electronic component is driven towards the contact strips for a certain distance so as to bend the contact strips. The bending force on the flexible contact strips will provide a reaction force on the electrical leads of the component, thereby creating the required contact pressure to ensure good contact.
FIG. 1 is an isometric view of contact strips 104 mounted on a mounting block 102 in a prior art test contactor 100. The contact strips 104 comprise elongated strips of electrically-conductive material which are centrally attached and mounted to a mounting block 102. When the contact strips 104 are not contacted with electrical leads of an electronic component, they are generally arranged horizontally and flat.
During testing of an electronic component, electrical leads on the electronic component are made to press on the ends of the contact strips 104. After contact has been made between the contact strips 104 and electrical leads of the electronic component, the electronic component is driven further downwards so as to bend the contact strips 104 from their horizontal positions and to stress them. The required contact pressure is formed to ensure good contact once the flexible contact strips 104 have been bent by a certain predetermined distance.
A disadvantage of adopting this approach is that, in addition to positioning the electronic component next to the contact strips during testing, the electronic component has to be driven by a certain distance towards the contact strips at every testing cycle until the contact resistance between the electrical leads of the component and the contact strips is low enough to create good contact therebetween. The additional time taken to drive the electronic component further by a predetermined distance during the electrical test of every component significantly slows down the testing cycle.
U.S. Pat. No. 5,743,749 describes an electronic component connector in which terminals are formed on a measurement circuit board. Support members are provided on the measurement circuit board to correspond to the terminals, and the support members have free end portions with contacts to come into contact with the electrical lead terminals of electronic components for testing. These contacts are formed of separate members from the support members in order to increase the freedom in selecting the material of the contact which need not have elasticity. Thus, the performance of the electronic component connector can be improved by the selection of appropriate materials to reduce interference during high frequency testing. However, this approach still requires a relatively large travel stroke in order to create enough contact force to ensure good contact and to reduce contact resistance during electrical testing.

Test contactor for electrical testing of electronic components


One aspect of the present invention relates to a method of forming a low k material layer on a semiconductor substrate, involving the steps of depositing a mixture containing a low k material and a casting solvent on the semiconductor substrate; optionally contacting the mixture with a transition solvent whereby the casting solvent is removed from the mixture to form a second mixture containing the low k material and the transition solvent; contacting the second mixture with a supercritical fluid whereby the transition solvent is removed from the second mixture; and permitting the supercritical fluid to evaporate thereby forming the low k material layer.

The present invention generally relates to processing a semiconductor substrate. In particular, the present invention relates to methods of forming a high quality low k material layer on a semiconductor substrate using a supercritical fluid.
High performance integrated circuit chips contain of millions of transistors that perform various functions including random access memory, central processing communications, and the like. Each of the transistors is interconnected with electrically conducting elements. In order to efficiently accomplish this on a single chip, a typical integrated circuit chip contains multiple layers of conducting elements. Since there are size constraints associated with placing millions of conducting elements on a chip having an area of only a few square centimeters, the connecting elements themselves are very small, and the distance that separates conducting elements is small as well. For example, a state-of-the-art integrated circuit produced today has a conductor width of 0.18 to 0.25 xcexcm and conductor spacing of 0.18 to 0.25 xcexcm.
Dielectric materials are widely used in the semiconductor industry to separate structures on an integrated circuit chip, such as separating metal interconnect layers from active devices. Dielectrics are also used to separate two adjacent metal interconnect layers to prevent shorting between the metal layers. With an increasing number of levels in integrated circuit chips, there is growing emphasis on the quality of so-called interlevel dielectrics. This is because multiple levels of metal interconnects are necessary in order to achieve higher packing densities and smaller chip sizes with increased circuit complexity.
The smaller geometries raise certain electrical performance problems that are not of concern in older generation integrated circuits. The reduced spacing results in increased electrical capacitance, which in turn causes capacitative interconnect delay that can slow down the operational speed of the circuit. Increased capacitance increases the amount of power that the integrated circuit requires to operate. Increased capacitance also causes cross-talk that can result in generating signal errors.
Since the dimensions of current integrated circuits are constrained, and since the trend is to continue decreasing geometries, it is necessary to reduce the capacitance in integrated circuit chips. Conventional semiconductor fabrication commonly uses high density or conventional silicon dioxide and/or spin-on glass as a dielectric.
One disadvantage associated with high density silicon dioxide and/or spin-on glass dielectrics is their relatively high permitivity or dielectric constant. Typically, high density silicon dioxide and/or spin-on glass have a relative (to permitivity of free space) dielectric constant of 3.9 or higher. High dielectric constant materials produce capacitive loads on the adjacent conductors which degrades performance of both high frequency and high density transistors.
Another disadvantage associated with high density silicon dioxide and/or spin-on glass dielectrics is that thicker dielectric layers are required to compensate for the high dielectric constant. Thicker layers result in larger geometry devices, increasing the overall size and cost of the integrated circuit chip while reducing functionality. Additionally, thick dielectric layers increase planarization problems, making it difficult to form multi-layer metallizations on top of the dielectrics.
An important factor for judging the quality of a dielectric is dielectric strength. Dielectric strength is typically referred to as breakdown voltage or breakdown field strength. Breakdown field strength is a property with units of volts per unit length at which an insulative material does not insulate, breaks down and results in a short circuit. Calculating the required minimum breakdown field strength for an integrated circuit involves taking the operating voltage of the circuit and dividing it by the separation distance between adjacent conducting elements. For example, in a 0.25 xcexcm technology integrated circuit that operates at a voltage of 3.3 volts, the minimum breakdown field strength required is 3.3 volts divided by 0.25 microns, which equals 13.2 V/xcexcm, or 0.132 MV/cm. Typical safety margins are several times this or a minimum of about 0.5 MV/cm. The breakdown field strength of air is less than 1 volt per micron. Another factor for judging the quality of a dielectric is leakage current. Leakage current is low level current flux through an insulator of field strength less than the breakdown field strength. A typical requirement for an integrated circuit is a leakage current density less than 2xc3x9710xe2x88x928 amps/cm2 and an applied electric field strength of 0.05 MV/cm.
Generally speaking, therefore, it is desirable to provide a dielectric material layer with a high breakdown field strength and low leakage current. Low k material layers are attractive in this respect because they possess both high breakdown field strength and low leakage current. However, there are problems associated with forming low k material layers. For instance, heat causes deleterious structural damage to a low k material layer or film (structural collapse of the low k material). Temperatures as low as 350xc2x0 C. can cause such damage in certain low k material layers. This is a problem because semiconductor processing often involves high temperature steps. Consequently, various layers used in fabricating semiconductor devices must be able to withstand high temperatures.
Another problem associated with low k material layers involves solvent removal after application. Incomplete solvent removal leads to undesirable increases in the dielectric constant of the subsequently formed low k material layer. Increases in the dielectric constant consequently degrade the electrical properties and thus the reliability of the electronic devices made with such low k materials. Incomplete solvent removal also provides a failure mechanism for a device formed with the low k material layer, since the unremoved solvent may vaporize out of the layer and damage another layer or structure within the device. Incomplete solvent removal is therefore a significant concern.
Yet another problem associated with low k material layers involves solvent removal by evaporation from low k material layers, in that evaporation creates high surface tension forces that sometimes induces deleterious structural collapse of the low k material layer.
The present invention provides methods for making semiconductor structures with low k insulation materials using a supercritical fluid. The present invention also provides methods for forming high quality low k material layers in semiconductor structures by minimizing and/or eliminating residual solvents in the low k material layers. The high quality low k material layers leads to the formation of electronic devices having desirable electrical properties. The low k material layers made in accordance with the present invention have at least one of high temperature stability, the absence of residual solvent, a desirable structural network, high breakdown field strength and low leakage current.
One aspect of the present invention relates to a method of forming a low k material layer on a semiconductor substrate, involving the steps of depositing a mixture containing a low k material and a casting solvent on the semiconductor substrate; optionally contacting the mixture with a transition solvent whereby the casting solvent is removed from the mixture to form a second mixture containing the low k material and the transition solvent; contacting the mixture or second mixture with a supercritical fluid whereby the casting solvent or the transition solvent is removed from the mixture or the second mixture; and permitting the supercritical fluid to evaporate thereby forming the low k material layer.
Another aspect the present invention relates to a method processing a low k material, involving the steps of depositing a mixture comprising the low k material and a casting solvent on a semiconductor substrate wherein the casting solvent comprises at least one of deionized water, a water based dispersion, a water-in-oil emulsion, an oil-in-water emulsion, benzenes, chlorobenzenes, anisole, cyclohexanone, a lower alkyl alcohol, a lower alkyl ketone, and a lower alkyl ester, wherein each alkyl group has 5 or less carbon atoms; contacting the mixture with a transition solvent whereby the casting solvent is removed from the mixture to form a second mixture comprising the low k material and the transition solvent, wherein the transition solvent comprises at least one of a lower alkyl alcohol, a lower alkyl ketone, and a lower alkyl ester, wherein each alkyl group has 5 or less carbon atoms; contacting the second mixture with a supercritical fluid whereby the transition solvent is removed from the second mixture; and permitting the supercritical fluid to evaporate thereby forming a low k material layer having a dielectric constant below about 3.8.
Yet another aspect of the present invention relates to a method of making a low k dieletric layer, involving the steps of depositing a mixture comprising a low k material and a casting solvent on a semiconductor substrate; contacting the mixture with an organic solvent whereby the casting solvent is removed from the mixture to form a second mixture comprising the low k material and the organic solvent, wherein the organic solvent comprises at least one of a ketone, an ester, an alcohol, an ether, and an aromatic hydrocarbon; contacting the second mixture with a supercritical fluid using spin coating whereby the organic solvent is removed from the second mixture, wherein the supercritical fluid comprises at least one of CO2, N2O, C2H6, CFH3, H2O, NH3, and CClF3; and permitting the supercritical fluid to evaporate thereby forming the low k dieletric layer having a dielectric constant below about 3.

Super critical drying of low k materials


An optical transmission system includes an optical transmitting apparatus that includes a polarization controller configured to change a polarization state of a signal light at an operating frequency included in a frequency range at which polarization trackability is obtained on a receiving side, based on a notified monitoring result, the optical transmitting apparatus being configured to output the signal light having the changed polarization state, and an optical receiving apparatus that is provided on the receiving side and includes a monitoring control unit configured to receive the signal light having the changed polarization state and monitor transmission quality of the received signal light, the optical receiving apparatus being configured to notify the optical transmitting apparatus of the monitoring result.

Parameters of light include wavelength, intensity, as well as polarization, which represent the direction of an electric field of light and the change of the electric field over time. In optical communication networks, when signal light propagates in an optical fiber transmission line, the state of polarization changes under the effect of environmental conditions, such as temperature, and under conditions such as external stress. It is a known fact that optical fiber transmission lines and optical amplifiers have polarization dependence, which causes the transmission characteristics of optical fiber transmission lines to deteriorate.
Polarization dependence is primarily caused by polarization dependence gain (PDG) and polarization dependence loss (PDL), and cause characteristics, such as the optical signal to noise ratio (OSNR) or Q-factor, to deteriorate.
As a technique for reducing the above effects of polarization dependence gain and polarization dependence loss, there is a proposed polarization scrambler that aggressively changes the polarization state of signal light and brings the signal light into a non-polarized state (a state in which electric fields are uniformly distributed in all directions) on the transmitting side.
The polarization scrambler performs polarization scrambling on signal light and transmits signal light that has a randomly polarized state. As a result, the degradation in transmission quality caused by polarization dependence gain and polarization dependence loss is reduced.
An optical transmission technique using a polarization scrambler has been proposed (see, for example, Japanese Laid-open Patent Publication Nos. 2000-196523 and 09-149006).
A polarization scrambler in the related art generally has a scrambling frequency (a frequency at which polarization rotation is performed) ranging from several hundreds of kHz to 1 MHz. At the scrambling frequency, a polarization state becomes random.
As a technique for realizing high-capacity long-distance transmission, a coherent receiver technology has recently received attention. The development of an optical transmission system that uses the coherent receiver technology is proceeding.
For example, with an optical transmission system in the related art that has a transmission speed less than or equal to 10 Gbps, the polarization dependence gain and polarization dependence loss are large. However, it is difficult to update the optical transmission system in the related art with the coherent receiver technology, because a polarization scrambler in the related art may not be usable.
The reason for this is that the scrambling frequency (ranging from several hundreds of kHz to 1 MHz) of a polarization scrambler in the related art exceeds a frequency (several tens of kHz) at which polarization trackability is obtained for coherent reception. If a polarization scrambler becomes unusable, the effects of polarization dependence, that is, polarization dependence gain and polarization dependence loss, occurs and degradation of transmission quality worsens.
Accordingly, there is an increasing demand for a technique to efficiently suppress degradation in transmission quality caused by polarization dependence, in other words polarization dependence gain and polarization dependence loss, even if an optical receiving apparatus that has limited polarization trackability, such as in coherent reception, is used in an optical transmission system in the related art.

Optical transmission system, optical transmitting apparatus, and optical receiving apparatus


The present invention relates to novel methods for the transformation of crop species, novel methods for the selection and identification of transformed plant cells and novel methods for recovery of regenerated whole plants. The method also relates to the development of plants with novel traits and plants that contain novel recombinant DNA constructs.

The development of transgenic crops requires methods for the stable insertion of recombinant DNA, a process typically referred to as transformation. Transformed plant cells are generated by the use of a variety of methods to insert foreign DNA into plant cells. These methods further employ the use of genetic constructs which contain genes encoding resistance to chemical selection agents such as antibiotics (e.g. kanamycin or hygromycin) or herbicides. Plant cells expressing selectable markers are preferentially obtained by culturing a population of plant cells subjected to a transformation process in the presence of media which contains, in addition to the selective agent, specific combinations of phytohormones and nutrients to allow cells to grow and regenerate to intact plants. Thus, the process of producing a transformed cell requires a means to physically insert foreign DNA as well as a means to select for those cells which have incorporated the DNA in an expressible and stable form.
Following the stable insertion and expression of the foreign DNA, regeneration of cells containing the foreign DNA leads to the recovery of whole plants, usually following shoot-, embryo- or organo-genesis. The regenerated plant tissue is induced, by a number of different means, typically by the alteration of tissue culture conditions, more typically by manipulation of phytohormones, to form a whole plant capable of forming seed and/or pollen, which can transfer the foreign DNA to subsequent generations. In some plant species, a major limitation is efficient selection and regeneration of plant cells following transfer of DNA, as opposed to the actual transfer of DNA into the cell. Thus, practical limitations on the use of standard transformation methods generally relate to the efficiency of selection and identification of transformed plant cells, not necessarily the transfer of DNA into the plant cell. Another step in the process that is often problematic is the regeneration of transformed cells into whole plants in the presence of a selective agent.
One potential problem related to the selection of plant cells is the effect of the selective agent on non-transformed cells, i.e. plant cells that do not contain the selectable marker. Often the selection process kills the majority of non-transformed cells, a process that, for a variety of physiological reasons, often reduces the efficiency or frequency of regeneration of transformed cells. Thus, the selective pressure needed to identify the cells containing the foreign DNA often proves to be an inhibitory factor to the efficient regeneration of plant cells.
Thus, methods that allow for the selection of plant cells without a direct lethal effect on the non-transformed cells may provide a means to reliably recover transformed plant cells. In addition, regeneration may prove to be more efficient, especially in those plant species, varieties or cells that are difficult to transform by means conventionally practiced. This problem is a major limitation for the routine and economical production of transformed plants.
It is believed that transformation of plant tissue results in only a small percentage of the total number of cells subjected to the transformation process actually incorporating the DNA into their nuclear DNA. Upon application of the selective agent, most plant cells die and may release substances (such as ethylene or senescence related compounds) that affect other nearby cells, including those containing the selectable marker gene and thus prevent efficient regeneration of these transformed cells. It appears that the death of the non-transformed cells may release substances inhibitory to the survival of the transformed cells. Accordingly a primary limitation for efficient production of transformed plants is the recovery of transformed plant cells and subsequent regeneration to whole plants. Methods which permit the rapid and efficient recovery of plant cells containing foreign DNA under conditions where the selection process does not lead to the death of non-transformed cells, (with subsequent inhibition of regeneration) would provide a convenient and efficient means to recover plants, particularly in those plant species where transformation has proven to be costly and time-consuming. Many plant species are capable of being transformed by introduced DNA, however the efficiency of the regeneration process is exceedingly low and prohibits the development of transgenic crops. Furthermore, the significant variation in tissue culture response or regeneration potential in tissue culture found within species, subspecies or varieties within a specific crop genus severely restricts the effective range of current transformation processes.
Brassica species are of special interest. Transformation of members of the Cruciferae family by Agrobacterium and other methods has been reported. A significant body of scientific work has accumulated that describes various methodologies, techniques and studies related to the generation of transgenic Brassica plants that contain foreign DNA of commercial interest and utility. A significant effort to achieve this was made through the early 1980's and still is being made. The technology has been advanced to the point where transformation is now routine for certain narrow genotypes of a species within the Brassicacea, however, it remains difficult within other species in the same family. In addition there is a strong influence of genotype on transformation success within those Brassicas that have been successfully transformed and technology that is more widely applicable to even the "recalcitrant" genotypes would be of great value to the industry. While there are many transgenic Brassica undergoing field evaluation, analysis of the field trial data clearly indicates that the majority (>95%) of the transgenic Brassica are B. napus types, much of the material has been derived from a narrow range of germplasm within B. napus. Part of the reason for this has been the difficulty of routinely obtaining transformed B. rapa and oleracea types as well as the fact that the development of commercial transgenic plants is still relatively recent.
However, many of the reports that relate specifically to Brassica transformation have detailed the difficulty in routinely obtaining transformed Brassica species by Agrobacterium mediated transformation. Many of the reports have shown success with one or two particular varieties, but there is no teaching of detailed methods that are generally applicable to all species within the Brassica genus. Although many manipulations of culture conditions can be employed, some varieties have proven to be extremely difficult to transform by previously reported methods.
Many of the initial Brassica transformation studies were carried out with B. napus cv Westar (Radke et al, Theor. Appl. Genet. 75:685–694, 1988; Moloney et al., Plant Cell Reports 8:238–242, 1989; Moloney et al., 1989, U.S. Pat. No. 5,188,958; Moloney et al., 1989, U.S. Pat. No. 5,463,174). Westar was a convenient choice since it responded to tissue culture and transformation protocols described in the references cited above and allowed recovery of transgenic plants. However; many Brassica transformation studies conducted using the described methods, or variations thereof, have produced results that are highly variable and are dependent upon the innate response of the specific plant materials to the transformation protocol. As an example, the transformation frequencies that have been achieved for Brassica napus are sometimes variable and very low (Fry et al., Plant Cell Reports 6:321–325, 1987; Mehra-Palta et al., In Proc 8th Int. Rapeseed Congress, Saskatoon, Saskatchewan, 1991; Swanson and Erickson, Theor. Appl. Genet. 78:831–835, 1989). Variable and often low transformation frequencies have also been observed with other Brassica species, such as B. oleracea (Christie and Earle, In Proc 5th Crucifer Genetics Workshop, Davis, pp 46–47, 1989; Metz et al., Plant Cell Reports 15: 287–292, 1995; Eimert and Siegemund, Plant Molec. Biol. 19:485–490, 1992; DeBlock et al., Plant Physiol. 91:694–701, 1989; Berthomieu and Jouanin, Plant Cell Reports 11:334–338; Toriyama et al, Theor. Appl. Genet. 81:769–776, 1991); B. rapa (Radke et al., Plant Cell Reports 11:499–505, 1992; Mukhopadhyay et al, Plant Cell Reports 11:506–513, 1992); B. juncea (Barfield and Pua, Plant Cell Reports 10:308–314, 1991; Deepak et al., Plant Cell Reports 12:462–467, 1993; Pua and Lee, Planta 196:69–76, 1995); B. nigra (Gupta et al, Plant Cell Reports 12:418–421, 1993); and B. carinata (Narasimhulu et al., Plant Cell Reports 11:359–362, 1992; Babic, M.Sc. Thesis, Univ of Saskatchewan, 1994).
The many Brassica species, varieties and cultivars represent a very diverse group with radically different morphologies and physiological characteristics. In addition to oilseed Brassica, the vegetable Brassicas represent a crop with significant economic value. This value could be enhanced by the addition of certain novel traits such as disease and insect resistance, male sterility systems for hybrid seed production, certain quality traits, and the like. Accordingly efficient transformation systems for broccoli, cabbage, cauliflower, kale and other Brassica vegetables would be valuable. Many Brassica vegetable species of commercial interest do not respond well or at all to the methods previously described. A transformation method is required which is useful for substantially all of the Brassica species and especially those previously recalcitrant to transformation.
In addition to obstacles encountered within the genus Brassica, other plant genera have exhibited similar phenomena. Many commercially important plant species or genera are difficult to transform and typically only a narrow range of specific genotype is amenable to transformation. This includes crops such as cotton, soybean, sunflower, cereal crops such as wheat, barley, rice and corn as well as many ornamental and vegetable crops. Often, a wide range of genotypes are amenable to culture and regeneration, but the combination of the selection and transformation process eliminates efficient regeneration and hence leads to extremely inefficient transformation of elite lines. Thus most transformation processes are conducted with a narrow germplasm, followed by characterization of the line and extensive backcrossing. Many transgenic crop varieties produced to date have been made by transformation of a specific variety that has been demonstrated as being amenable to transformation followed by extensive crossing to those varieties most suitable for widespread cultivation. This trait introgression is time-consuming and expensive.
Accordingly, methods that permit the efficient transformation of a wide range of crop species and individual varieties, are essentially genotype independent and capable of being used to impart a variety of novel traits will be of significant benefit to the industry. Furthermore, methods that avoid, as a primary step in the process, the use of a toxic selective agent which kills non-transformed cells, may provide opportunities to achieve the efficient regeneration of plants in species where this has been found to be difficult or in those plant varieties where this is currently not possible.
It has been noted that one of the most efficient transformation processes is the natural infectivity process of Agrobacterium species. Agrobacterium is a free-living Gram-negative soil bacterium. Virulent strains of this bacterium are able to infect plant tissue and induce the production of a neoplastic growth commonly referred to as a crown gall. Virulent strains of Agrobacterium contain a large plasmid DNA known as a Ti-plasmid that contains genes required for plasmid transfer and replication as well as a region of DNA that is called T-DNA. The T-DNA region is bordered by T-DNA border sequences that are crucial to the DNA transfer process. These T-DNA border sequences are recognized by the vir genes encoded on the Ti-plasmid and the vir genes are responsible for the DNA transfer process. Thus the native Ti-Plasmid contains the vir genes as well as the T-DNA region and the T-DNA borders required for efficient DNA transfer to a recipient plant cell. The entire complement of these genetic elements, in conjunction with genes encoded on the bacterial chromosome allow the efficient transfer of the T-DNA region into plant cells with subsequent stable integration and expression of the various genes encoded by the T-DNA.
The T-DNA transferred and integrated into the plant cell nucleus contains a number of genes that encode enzymes for the production of unusual amino acids (opines) and genes that encode enzymes capable of producing plant hormones and genes responsible for the modulation of plant development. As such, there are a relatively large number of genes within the T-DNA that are transferred to the plant cell, the function of all of genes has not been completely elucidated in the Agrobacterium genus. However, the primary effect of the genes in the T-DNA are at the level of plant cell growth and development. Following infection by Agrobacterium, the plant cells infected with the T-DNA undergo an uncontrolled proliferation due to the activity of the T-DNA genes. These genes, referred to as "oncogenes" because of the phenotype they confer, permit hormone-independent growth of transformed cells in culture. The expression of these various oncogenes causes the formation of gall callus, callus that is not capable of regeneration to differentiated complex plant structures such as fertile shoots, or whole plants.
The process of gall or tumor formation is very efficient, essentially 100% of inoculated Agrobacterium susceptible plant tissue will form a tumor. Thus the natural Agrobacterium DNA transfer process is exceedingly efficient. In addition, the physiological processes of crown gall formation are also very efficient in conferring a transformed phenotype. Furthermore, most wild-type Agrobacterium have broad host range and are capable of transferring large segments of DNA, typically T-DNA transferred to plant cells contains up to 25 kilobases of DNA (e.g. nopaline strains) or more (e.g. octopine strains). Thus the naturally occurring DNA transfer system of Agrobacterium provides an efficient means to transfer DNA into a plant cell and the subsequent formation and identification of transformed tissue.
Accordingly, numerous methods of using Agrobacterium to transfer DNA into plant cells have been developed. Typically these have been based on the engineering of the Ti-plasmid to no longer contain the genes responsible for altered morphology ("oncogenes") and replacing these genes with a recombinant gene encoding a trait of interest. Linked to this trait of interest is a gene encoding a selectable marker such that cells that receive the DNA can be selected. Usually the vir genes are left intact, however some methods include the alteration of the vir genes in one form or another.
There are two primary types of Agrobacterium based plant transformation systems, binary and co-integrate methods. The use of the binary transformation system is described by Schilperoort et al in U.S. Pat. No. 4,940,838. An example of the co-integrate system is found in Fraley et al., Biotechnology, 3:629–635, 1985. Both the co-integrate and binary systems are based on replacing the normally oncogenic complement of Agrobacterium genes with engineered, non-oncogenic DNA, typically DNA that comprises a selectable marker and a gene encoding a novel trait. The T-DNA border repeats are maintained in both systems and the natural DNA transfer process is used to transfer the portion of DNA located between the T-DNA borders into the plant cell. Thus, these transformation methods avoid the problems associated with recovery of morphologically normal plant cells when using methods wherein the oncogenic region of the Ti-plasmid is inserted into a plant cell. Therefore, these methods rely on the presence of a selectable marker to recovery transformed cells since the selection based on the activity of the oncogenes can no longer be used.
It has been recognized that the presence of oncogenes within the DNA transferred to plant cells prevents the regeneration of morphologically normal plants. It has also been recognized that each of the various oncogenes encoded by the T-DNA has a different role and the total activity of the various oncogenes leads to crown gall formation. Independently each of the primary oncogenes has a defined function and typically the presence of only one or two functional oncogenes leads to the formation of morphologically abnormal plants. This is in contrast to the crown galls produced by the activity of all of the oncogenes, crown galls (or callus derived from crown gall tissue) cannot regenerate or form morphologically normal plants. Indeed, crown gall tissue is not capable of regeneration to differentiated plant tissue. Accordingly crown gall tissue has been considered to represent a terminal tissue in the Agrobacterium infectious process. Thus it has been recognized in the art that the full complement of oncogenes contained within the T-DNA eliminates the potential for recovery of morphologically normal plants.
However, it has been shown in the art that one or two oncogenes can be included in a transformation vector for plants and the activity of these oncogenes used as a method to screen for transformed cells. For example, Ebunuma et al., (Proc. Natl. Acad. Sci. USA 94:2117–2121, 1997, U.S. Pat. No. 5,965,791) describe a plant transformation vector that comprises the isopentyl transferase gene from Agrobacterium (typically referred to as oncogene 4) as a means to identify transformed plant cells. In this method, the activity of the oncogene causes the production of cytokinin, a plant hormone that causes shoot production. In this case, a "shooty" mutant is produced (a morphologically abnormal shoot) and the plant cells are selected on the basis of abnormal shoot formation as well as selection for resistance to kanamycin or herbicides. As an added feature of the method, the oncogene is bordered by transposition elements that permit the eventual loss of the oncogene from the transformed plant cell. The arrangement of DNA in the vector is such that the gene of interest remains in the transformed plant cell.
Although this method relies on the activity of oncogene 4 to discriminate transformed versus non-transformed cells, the method requires visual discrimination of regenerating plant shoots, can lead to the formation of chimaeric plants and requires various tissue culture manipulations to recover single cell derived transgenic plants.
Indeed the method described in U.S. Pat. No. 5,965,791 relies on the regeneration of morphologically abnormal plant structures as a marker for transformation. The morphological abnormality induction gene causes the formation of abnormal plant structures, and in many cases somataclonal and culture variation lead to the same phenotypic effect, thus further analysis is required to fully obtain transgenic plants. Thus the method has limitations and may not provide a convenient means to transform recalcitrant plant species or varieties. The method still relies on the use of a dis-armed Agrobacterium strain and the efficiency of transformation is correspondingly reduced relative to the natural formation of crown galls.
Similarly, it has been shown that the oncogene 2 can be used for discrimination of transformed plant cells, and recovery of transgenic plants following regeneration and selection of transgenic cells on appropriate media or under appropriate selective conditions. Keller et al., (International Publication No. WO 00/37060) demonstrates that the isolated oncogene 2 can be used for discrimination of transgenic plant cells following transformation and culturing on selective media. Abnormal plantlets are produced in the presence of the oncogene 2 enzyme and an appropriate substrate for the enzyme. As above, the selection of a transformed plant relies on the formation of a morphologically abnormal structure.
In both of these examples, the usual transfer process of DNA from Agrobacterium to a plant cell occurs as a result of the modification of a plant transformation vector to comprise a binary vector system and a dis-armed T-DNA region. These modifications have typically included the elimination of most if not all of the natural sequences found within the T-DNA, including many open reading frames and genes whose function is not well understood but likely to play an important role in the efficiency of the transfer and integration process. These oncogenes utilized are modified and outside of the normal environment that characterizes their naturally occurring roles in the formation of crown gall tissue.
However, the natural T-DNA transfer process and subsequent formation of crown galls or plant tumors with wild-type T-DNA is a highly efficient process. The process is usually very efficient even on plant varieties and species that are recalcitrant to usual tissue-culture protocols for the introduction of DNA by Agrobacterium and recovery of transgenic plants (for example various Brassica species or cotton). In most instances crown galls will form easily on decapitated plants or wounded stems, even on plant genotypes recalcitrant to transformation using typical dis-armed vectors. Crown gall formation is also easily scored and true galls (i.e., those carrying the entire T-DNA region) are not capable of forming any differentiated plant tissue. Although spontaneous shoots or roots can form with some Agrobacterium strains, usually crown galls do not form differentiated cells, even morphologically abnormal differentiated cells unless one or more of the encoded oncogenes undergoes a mutation or loss of function. Crown galls can also be easily cultured by simple growth on hormone free minimal media. Crown galls can also be made bacteria free by culturing in antibiotic solution for a period of time. Thus it is a trivial process to obtain bacteria-free, transformed plant cells from many different plant species comprising intact oncogenic T-DNA.
Thus, a method for plant transformation that could take advantage of this efficient process, along with the easy means of identifying the transformed cells (by hormone-independent growth in culture) can provide many advantages including efficiency of transformation and selection of transformed plant cells. However, the art teaches that when the naturally occurring oncogenic region is used, recovery of morphologically normal plant cells is not possible. Thus, methods for recovering morphologically normal plant cells following the formation of crown galls are not available and hence the efficiency and wide host range of the natural T-DNA transfer process cannot be used as a means to produce morphologically normal transformed plants from a wide range of plant species.

Methods and constructs for plant transformation


A plurality of discharge resistors Rd1 to Rdn having different resistance values is provided. A CPU 72 selects one from a plurality of unit cells B1 to B16 as a connection cell and selects one resistance value according to a voltage across the connection cell from the plurality of resistance values. The CPU 72 turns on/off a cell selecting switch group 2, a polarity reversing switch group 3 and a discharge resistor selecting switch group 5 and connects the connection cell to the discharge resistor having the selected resistance value to discharge stored electric charge of the connection cell, thereby equalizing the respective voltages across the unit cells.

1. Field of the Technical Field
The present invention relates to an apparatus for regulating state of charge in a battery assembly, and more particularly, to an apparatus for regulating state of charge in a battery assembly which includes secondary cells as a plurality of unit cells connected in series.
2. Description of the Related Art
In an electric car driven by an electric motor and in a hybrid electric car driven by both an engine and an electric motor, a battery assembly including a plurality of secondary cells as unit cells connected in series, such as a nickel-metal hydride battery or a lithium battery, has been employed as an electric source for the electric motor.
It has been known that the above-described battery assembly has had such a problem that due to repeated charging and discharging of electricity, variations may occur in respective voltages across the unit cells depending on the state of charge (SOC) of the unit cells, and in the case where charging and discharging of electricity are repeated while the variations remain unsolved, some of the unit cells may fall in an excessively charged state or in an excessively discharged state.
Under the circumstances, a discharge type apparatus for regulating state of charge, which can solve variations in respective voltages across a plurality of unit cells by extracting a minimum unit cell having a minimum voltage from the plurality of unit cells, sequentially connecting the unit cells except the minimum unit cell to a discharge resistor, and discharging stored electric charge until the respective voltages across the connected unit cells are equal to the voltage across the minimum unit cell, is proposed (for example, Japanese Unexamined Patent Application Publication No. 2002-199510).
In addition, a charge pump type apparatus for regulating state of charge, which can solve variations in the respective voltages across a plurality of unit cells by transferring electric charge from a unit cell having a high voltage to a unit cell having a low voltage through a capacitor is proposed. As an example of the charge pump type apparatus for regulating the state of charge, it is proposed that unit cells are sequentially connected to a capacitor (Japanese Unexamined Patent Application Publication 1998-225005). In this structure, electric charge of the unit cell which has a higher voltage than a voltage across the capacitor is transferred to the capacitor, and contrarily, electric charge of the capacitor is transferred to the unit cell which has a lower voltage than the voltage across the capacitor. In other words, the stored electric charge is transferred from the unit cell having the higher voltage to the unit cell having the lower voltage by way of the capacitor, and consequently, the variations in the respective voltages across the unit cells can be eliminated.
It is proposed that a capacitor is alternately connected to a maximum unit cell having a maximum voltage and a minimum unit cell having a minimum voltage (Japanese Unexamined Patent Application Publication No. 2004-120871). In this structure, since the electric charge is repeatedly transferred from the maximum unit cell to the minimum unit cell, the respective voltages across the unit cells can be equalized in a short time. Since the capacitor has a very small internal resistance, connection between each of the unit cells and the capacitor is necessarily performed by a current limiting resistor, the current limiting resistor limits charging and discharging current which flows in the unit cells and over-current is prevented from flowing.
However, in the discharge type apparatus for regulating the state of charge, the discharge resistor having one resistance value is connected regardless of the sizes of the voltages across the unit cells. The resistance value of the discharge resistor is determined to a value for allowing discharge current equal to or less than allowable current to flow when a unit cell having a full-charged state is connected to the discharge resistor. The allowable current is determined according to the characteristics of the secondary cell included as the unit cell and the secondary cell may deteriorate when the discharge is performed by current exceeding the allowable current.
Accordingly, when the voltage across the unit cell is relatively large, discharge current which flows from the unit cell to the discharge resistor is high and the voltage across the unit cell becomes the voltage across the minimum unit cell. In contrast, when the voltage across the unit cell is small, the discharge current which flows from the unit cell to the discharge resistor decreases and it takes a considerable time to regulate the voltage across the unit cell to the voltage across the minimum unit cell. Thus, as the voltage across the unit cell decreases, it takes a considerable time to equalize the voltages across the plurality of unit cells.
In the charge pump type apparatus for regulating the state of charge, the current limiting resistor having one resistance value is connected regardless of a difference between a voltage across the unit cell and a voltage across the capacitor. Accordingly, when the difference between the voltage across the unit cell and the voltage across the capacitor is large, charge/discharge current which flows between the unit cell and the capacitor is high and a large amount of charge can be transferred in a short time. In contrast, when the difference between the voltage across the unit cell and the voltage across the capacitor decreases by equalization, the charge/discharge current which flows between the unit cell and the capacitor decreases and thus it takes a considerable time to transfer the electric charge. As the results, as the difference between the voltage across the unit cell and the voltage across the capacitor decreases, it takes a considerable time to equalize the respective voltages across the plurality of unit cells.

Apparatus for regulating state of charge in battery assembly


An auger system having an auger with an internal measurement system that is contained within the auger. The measurement system has a power source located within the auger and a sensor for measuring at least one condition within the auger. The measurement system is connected to the power source and a transmitter is powered by the power source to transmit a signal from the sensor. A receiver receives the signal from the transmitter and is spaced from the transmitter. The signal is then sent to a control system that compares the signal to a predetermined value to determine whether the condition measured is within an acceptable range. The control system may alter inputs into components for moving the auger until said condition is within an acceptable range.

Auger systems are commonly used to move granular materials that are stored in piles. Such augers can be used to move piles of material located within various storage vessels (such as buildings, tanks, silos, or domes) or they can be used to move material stored in open piles that are not inside any storage building. The augers typically include a hollow shaft surrounded by flights that convey material in an axial direction along the auger as it is rotated about its central axis. In addition to rotating about its axis, an auger is advanced laterally into a pile of material that rests upon the auger. There are two basic types of unloading auger systems that are defined by how their lateral movement through the pile of material takes place:
1) augers that rotate in a circular fashion through a pile and convey the stored material to a center point and into a secondary conveyor outside of the pile.
2) augers that move linearly through a pile to convey the stored material to a secondary conveyor outside of the pile.
The loads that the auger and its mechanical drive system experience are dependent upon numerous factors, including but not limited to the height and size of the storage vessel, the depth of the stored material, the characteristics of the stored material, the temperature and humidity of the storage environment, the design of the auger system, the speed of auger rotation and the rate of auger advancement into the stored material. The loads placed on an auger and its drive system lead to stress within them.
As the auger advances into the pile, the auger can bow or deflect as a result of forces that act laterally on the auger. Furthermore, some materials cause the auger to want to climb onto the pile, providing another source for deflection of the auger. The forces from rotating a deflected auger can cause metal fatigue and bearing wear, both of which can result in failure of the auger system. Applying a lateral force to advance an auger into a pile causes cyclical forces as the auger rotates about its axis. Cyclical forces can exacerbate metal fatigue that eventually results in fractures or breakage of the auger tube. Bearing wear can eventually result in excessive bearing temperature leading to bearing failure and subsequent auger failure.
Either bearing failure or auger failure can also occur as a result of excessive torque or thrust loads in response to the auger advancing into the material pile and conveying material from that pile. Auger vibration is another factor which can lead to premature auger failure.
To operate an auger system in an optimally efficient manner, the auger rotational speed and the auger advancement rate into the material pile should be controlled to keep auger parameters such as deflection, torque, thrust, vibration and temperature limited to within an acceptable range. Each of these parameters can cause stress on the auger that may cause it to fail prematurely.
Traditionally, estimating auger parameters to keep them within acceptable levels has been limited to indirect measurements. Loads placed on an auger can be estimated indirectly by monitoring the current drawn through the electrically-powered auger-drive systems or through monitoring the hydraulic pressure on hydraulically-powered auger-drive systems. The auger rotation and advancement can be controlled through feedback from these indirect auger load measurements. However, these traditional methods of control are only marginally effective as they do not directly measure the actual auger deflection or auger stress. Additionally, indirectly measuring the aforementioned parameters can only provide an inaccurate estimate of stress and deflection, and even that is only possible when the construction of the auger is considered.
Prior to the method described here, direct measurement of auger parameters on an operating auger system has not been accomplished. Since the auger is rotating and also at least partially covered with material as it moves into and conveys material from the pile, taking real-time direct measurements of auger conditions has been problematic because of three factors: 1) the measurements would need to be taken from inside the rotating auger, 2) sufficient power would need to be supplied to the measurement apparatus located inside the rotating auger, and 3) the measurement results would need to be transmitted to a controller located outside the rotating auger. Taking measurements from inside the auger is difficult because the auger is typically made of metal which is conductive and therefore limits wireless transmission of data. Furthermore, since the typical auger rotation rate is between 10 and 200 rpm the use of electrical unions to transmit power and data is inherently problematic, especially since auger systems are commonly located in hazardous or explosive environments and any traditional revolving contact carries the risk of generating sparks.
The present invention solves these problems, making possible real-time direct measurements of auger parameters inside a rotating auger system. Measurable parameters include, but are not limited to, deflection, stress, torque load, thrust load, vibration and temperature. The measurements of these auger parameters are then transmitted to an auger control system which uses the measurements as feedback to alter the movement of the auger in order to maintain the auger parameters within a desired range and/or to notify the operator of auger conditions.

Internal measurement feedback auger system


The present invention relates to a composite concrete building material comprising cementatious materials; and foam glass aggregates. The cementatious materials may comprise cement, sand and fly ash. The cementatious materials may also comprise other materials, including, for example, reinforcing fibers. In one embodiment the reinforcing fibers are comprised of one or more of the following materials: glass, steel, titanium, other metals, carbon, or Kevlar. The foam glass aggregates may have a closed pore structure and average pore size of 1.0 mm or less, wherein said average pore size is measured based on the distance between two farthest points of pore surface. The foam glass aggregate may have an average density of 30 to 100 PCF. The foam glass aggregate may have a compression strength of 2000 PSI or greater. The foam glass aggregates may be on average between 0.1 inches and approximately 2.0 inches in their largest diameter.

In construction, concrete is a composite building material made from the combination of aggregate and cement binder. The most common form of concrete is Portland cement concrete, which consists of mineral aggregate (generally gravel and sand), Portland cement and water. When water is added to the concrete mixture, the cement hydrates, gluing the other components together and eventually creating a stone-like material. When used in the generic sense, this is the material referred to by the term concrete. Concrete is used to make pavements, building structures, foundations, motorways/roads, overpasses, parking structures, and bases for gates/fences/poles. The shortcomings in conventional concrete as a building material are now described.
One problem with concrete is that it is very heavy with respect to its unit volume. Due to this high density, when concrete is used as a building material, additional support is required to compensate for this heavy weight. Thus, some have tried in the past to make lower density concrete (and thus lighter concrete) by placing air/gas bubbles in the concrete. The problem of most methods used to lower density is that such methods also lower strength. That may be acceptable for a wall panel, but not for a support structure. When the density is lower in a structural panel, it is less strong, and thus requires an increased volume of concrete to insure that it is sufficiently supported. Thus, what is needed is a lighter concrete material which retains the strength typically associated with heavier concrete.
Another method used in the past to lower the density of concrete (having a specific gravity of approximately 2.4) has been to use low density aggregates, such as sea shells (having a specific gravity of approximately 1.55), to lower the density of the concrete (and thus lighten the concrete). The combination of concrete with aggregate is referred to herein as "composite concrete". Aggregate is the component of a composite material used to resist compressive stress. For efficient filling, aggregate should be much smaller than the finished item, but have a wide variety of sizes. The "cementatious portion" of "composite concrete" can be comprised of cement, sand and possibly other additives, such as fly ash. Composite concrete which contains the sea shell aggregate has a lower density (118 lbs/cubic foot (PCF)), as compared to typical concrete (140-150 PCF). The use of sea shells as an aggregate in composite concrete reduces the weight of a structural member by approximately 17%, when the composite concrete is comprised 60 wt % cementation portion (e.g., cement, sand and fly ash), 32.5 wt % sea shell aggregate and 7.5 wt % air. While this composite concrete is useful, it is highly desirable to develop a Composite concrete which has an average density of less than 110 PCF.
Other attempts to lower the density of composite concrete have been made by using other low density aggregates, such as plastics. However, the problem with using these other types of aggregates in composite concrete is that when stressed, the composite concrete will tend to crack along the interface of the aggregates and the cementatious portion. It substantially weakens the resulting product if the boundary is weaker than either phase (aggregate or cementatious portion). This results in a weaker composite concrete. Thus, what is needed is a lower density aggregate that will be strong and adhere to the cementatious portion, so as to form a stronger, lower density composite concrete.
The concept of using foam glass as a construction material is also well known in the prior art. Generally such foam glass has been used as a high temperature insulator and thus seeks to minimize its density and weight and is not used as an aggregate or filler for composite concrete in building materials. The shortcoming in such conventional foam glass as relevant to this long standing problem is now described.
For example, Pittsburgh Corning Corporation ("PCC") of Pittsburgh, Pa. has developed and marketed a product known as Foam Glas® Insulation Systems, which is described in U.S. Pat. Nos. 3,959,541, 4,119,422, 4,198,224, 4,571,321 and 4,623,585. Since the purpose of this tile is to be used as thermal insulation, it lacks surface strength, and can be dented very easily. Because the Foam Glas® Insulation Systems tile is of relatively low density, e.g., 9.5 PCF, such tiles will easily break when exerted to forces typically asserted on structural members of a building.
Unlike the prior art discussed above, the composite concrete using foam glass aggregate of the present invention can be used like concrete, but has a greater strength per unit weight.
Thus, while the prior art is of interest, the known methods and apparatus of the prior art present several limitations which the present invention seeks to overcome.
In particular, it is an object of the present invention to provide a strong, lower density composite concrete which comprises cementatious portion and foam glass aggregate which can be used as a structural member of a building.
It is a further object of the present invention to make a lightweight aggregate that when used in composite concrete has substantially higher strength to weight ratio than concrete.
It is another object of the present invention to make an aggregate that will not absorb substantial amounts of water from the wet concrete when it is formed.
A still further object of the present invention is to make an aggregate that will form a strong bond with the cementatious portion when formed into a composite concrete.
These and other objects will become apparent from the foregoing description.

Strong, lower density composite concrete building material with foam glass aggregate


A program product for use in generating test benches for verifying test structures embedded in a circuit, comprises a verification specification processor for parsing a verification specification containing test specifications for selected test structures and a test bench generator for each of one or more types of embedded test structures, each test bench generator being operable to process a test structure specification of a test structure of a corresponding test structure type and generate a test bench using data contained in said test specifications of said verification specification, data contained in said test structure specification and data contained in a test connection specification.

1. Field of the Invention
The present invention relates, in general, to integrated circuit design and, more specifically, integration of test structures into circuit designs and verification of the resulting design.
2. Description of Related Art
As integrated circuits continue to become increasingly more complex, it is becoming increasingly more important to embed into the circuits test structures or objects which can be used during and after manufacture to test the circuit and its various sub-circuits and components. The generation, integration and verification of these test structures is complex and tedious because a circuit may require many specialized test structures and may include embedded circuit blocks which also require test structures. By way of example, FIG. 1 illustrates a relatively simple test ready circuit 10 having a variety of embedded test structures. The circuit includes an embedded circuit block 12 which has logic 14, a dynamic random access memory (DRAM) 16, and a legacy core 18. The test structures which are embedded in embedded block 12 include a logic test controller 20 associated with logic 14, a memory test controller 22 associated with DRAM 16 and a core socket 24 which provides isolation and access to legacy core 18. Top module 30 of circuit 10 includes logic 32, two memory units, including a static Random access memory (SRAM) 34 and read only memory (ROM) 36, a phase locked loop (PLL) 38, an analog-to-digital converter (ADC) 40 and a number of circuit input and output pins. The test structures which were added to the top module include a logic test controller 42 associated with logic 32, a memory test controller 44 associated with SRAM 34 and ROM 36, a phase locked loop test controller 46 associated with PLL 38, an ADC test controller 48 associated with ADC 40, interconnect test controllers 50, 52, and 54, and a test access port (TAP) 56 connected to the various test controllers. Logic blocks 14 and 32 are comprised of memory elements and combinational gates. Memory elements were converted to scannable memory elements and arranged into scan chains. In general, embedded test controllers generate test vectors and analyze output response of sub-circuits and components. The embedded test structures are used cooperatively for testing sub-blocks, which may be buried deep within an embedded block, from the circuit pins such as the test access port.
Automation tools, available from the patentee, LogicVision, Inc. of San Jose, Calif., may be used to generate and verify the test structures and assemble them into a circuit description of a circuit under development. Generally, each test structure has a specialized set of automation tools which provide several optional features, which or may not be included in a particular circuit, depending on the desires of the designer.
Thus, in addition to the complexity of the circuit itself and of the test structures which must be designed into the circuit, a designer faces the additional complexity of operating various automation tools which must be used to analyze the circuit, create the appropriate test structures, create test vectors and patterns to test the circuit, importantly, verify the test structures to ensure that they operate according to design specifications.
Once all test structures have been embedded in the circuit and the circuit design process is substantially complete, all embedded test structures must be verified again, possibly several times, prior to manufacture of the circuit as well as after manufacture.
The embedded test verification process varies from test structure to test structure, but, in general, the process involves operating test controllers in all of their respective modes of operation, and includes generating test benches and scripts to exercise the test controllers on a circuit simulator.
Dedicated verification tools have been developed in an effort to facilitate the verification process. For example, a logic test controller verification tool is required for logic test controllers, a memory test controller verification tool is required for memory test controllers, etc. As indicated above, it is often necessary to run a verification tool several times to test the various modes of a controller. typically a test controller is verified after it has been generated (created), but before it has been integrated into the circuit. This involves exercising the controller directly from its ports. It is verified again after the controller has been integrated into the circuit. This involves exercising the controller more remotely, i.e. from its ports of the circuit. The controller is verified again after top module test structures, such as a TAP, have been inserted into the circuit. In this case, the controller exercised from the TAP to circuit block ports and from the block ports to the controller ports. Finally, all test controllers must be verified again during a test structure sign-off flow. This verification procedure must be performed for each test controller. In the circuit of FIG. 1, there are at least nine test controllers, the test access port, various scan chains and other test structures which must be verified.
It will be seen, then, that each verification tool must be operated several times during the course of embedding test structures into a circuit and that there may be many verification tools which must be used. Clearly, the test structure verification process is complex.
There is a need for a single, unified verification tool and method for simplifying the verification process in circuits having embedded test structures and that can be used during test structure embedding phase of a circuit design, as well as during the final circuit verification phase of circuit design. There is also a need for a verification tool that will generate a test program that will test all test structures in the circuit prior to and after manufacture.

Verification of embedded test structures in circuit designs


The invention pertains to a probe for sensing the characteristics of a surface of a workpiece which contains a probe tip that is movably held and prestressed essentially in the direction of the tip (Z-direction) and mounted without play to a first acceleration transducer. The first acceleration transducer transforms the movements of the probe tip and consequently the measurement data into acceleration data, with the first acceleration transducer being movably held and prestressed in the direction of the tip (Z-direction) and fixedly connected to the probe tip. A first integrator performs double integration with respect to time of the acceleration data from the first acceleration transducer, thereby forming longitudinal measurement data which correspond to the features of the sensed surface. The probe is thus able to sense the shape as well as the undulations, or roughness of the surface of a workpiece and outputs the features in the form of a corresponding measurement voltage.

The present invention relates generally to a probe for sensing and measuring the shape, undulations, or roughness of a surface.
Probes of the pertinent type are publically known. Depending on the design, they make it possible to sense and measure the shape, undulations, or roughness of a surface. In the following description, the term xe2x80x9ccharacteristicsxe2x80x9d includes all three sensing and measuring options.
A probe for sensing the characteristics of a surface of a workpiece is known from DE 26 60 993 C2. This probe contains an electromechanical measuring transducer; the probe arm of the measuring transducer is provided with a probe tip and is prestressed in the sensing direction. The entire measuring probe is mounted on a feed unit that guides the probe tip of the measuring transducer over the surface to be examined. The measuring transducer transforms the movements of the probe tip in the direction of the tip (Z-direction) into corresponding measurement data. Since the feed unit moves the measuring transducer at constant speed, the measurement data can be recorded, e.g., on a paper tape that also runs at a constant speed as a function of time. In this case, a linear dependence is always assumed; however, a constant feed movement is a prerequisite for such a linear dependence, so that there are strict requirements for maintaining the feed movement constant. This means that a feed unit which meets these strict requirements must be provided. In addition, such a feed unit requires special measures to maintain the electromechanical measuring transducer within its operation region, e.g., such as those described in DE 27 25 072 A1 and DE 41 32 724 A1, if the surface to be sensed is not flat due to the shape of the workpiece to be sensed or due to excessive undulations, i.e., if a change in the direction of the advance movement is necessary. However, the shape or undulations, of the surface are not reflected in the form of a measuring voltage by the measuring transducer; thus, the shape or undulations, of the surface are lost.
DE 35 43 906 A1 discloses a probe for sensing the features of a workpiece surface with a probe tip that is arranged on a probe arm that can be pivoted essentially in the direction of the tip about a pivot bearing, with the probe tip being arranged at a certain distance from the pivot bearing. This probe also contains a transducer for transforming the movements of the probe tip into corresponding measurement data.
DE 35 43 906 A1 also describes a probe for sensing the features of a workpiece surface and contains a base body, a means for realizing a uniform linear movement of the base body in the sensing direction, a probe arm that is arranged on the base body and that can be pivoted about a pivot bearing, a probe tip that is arranged on the probe arm at a distance from the pivot bearing, and a measuring transducer for generating a measurement signal as a function of the movements of the probe tip in the direction of the tip while sensing a surface.
DE 196 37 554 A1 discloses a device for sensing the characteristics of a surface of a workpiece which contains a movably held probe tip, transducers for transforming the movements of the probe tip into corresponding measuring values and additional transducers for transforming the movements of the measurement probe that carries the probe tip into corresponding measurement data. The additional transducers consist of acceleration transducers, some of which are realized in the form of rotary acceleration transducers, which transform the pertinent measurement data into acceleration data. These transducers are connected without rotational play to the measuring probe, where an integrator that performs a double integration of the acceleration data over time as used to form the longitudinal dimensions that correspond to the positions of the measuring probe. Acceleration transducers only serve for measuring the portion of the probe tip movement that the probe tip carries out due to the movement of the measuring probe that carries the probe tip, primarily for measuring and correcting a generally undesirable relative movement between the measuring probe and the object to be measured.
U.S. Pat. No. 4,422,322 discloses a device for sensing the features of a road surface. A measuring vehicle with its wheels that roll on the road surface to be sensed serves as the measuring element. A transducer serves for transforming the movements of the measuring vehicle perpendicular to the road surface into corresponding measurement data, where the transducer consists of an acceleration transducer that transforms the measurement data into acceleration data and is rigidly connected to the spring-suspended mass of the measuring vehicle. An integrator performs a double integration of the acceleration data with respect to time [sic; with respect to distance] in order to form longitudinal measurement data that correspond to the features of the sensed road surface. This known device is not suitable for sensing the surface of a workpiece.
U.S. Pat. No. 5,850,289 discloses a device for sensing an object in order to determine its shape and three-dimensional surface characteristic. In this case, the sensing device is freely moved relative to the object and the movement or position data of the sensing device is determined by means of an acceleration transducer. The sensing takes place in such a way that a visual pattern is projected onto the surface of the object and the changes in the pattern are visually examined, with a signal for correcting the movement of the sensing device being formed therefrom. This known device is not suitable for sensing the roughness of the surface of a workpiece.
The invention is based on the objective of developing a probe for sensing the features of a workpiece surface, i.e., the shape, undulations, or roughness, which makes it possible to sense and transform into corresponding measurement data arbitrary irregularities of the workpiece surface, i.e., its shape, undulations, or roughness.
The basic idea of the invention consists of measuring the accelerations or speeds caused by the excursions rather than measuring the excursions of a probe tip during the sensing of the surface, with the value of the excursion subsequently being determined from said accelerations or speeds by means of an integration with respect to time.
According to one embodiment of the invention, linear accelerations are evaluated for this purpose. According to the present invention, the first transducer is realized in the form of a first acceleration transducer that transforms the measurement data into acceleration data, where said acceleration transducer is movably held and prestressed in the direction of the tip (Z-direction) and rigidly connected to the probe tip. Consequently, this first acceleration transducer is able to measure a wide range of movements, i.e., substantial differences in height that correspond to the shape of the surface, less substantial differences in height that correspond to undulations, of the surface, and minute differences in height that correspond to roughness of the surface. The desired measuring values can be separated from one another by means of a downstream filter, namely, a low-pass filter for the shape, a bandpass filter for the undulations, and a high-pass filter for the roughness.
According to an additional refinement of this embodiment of the invention, a second acceleration transducer is provided for transforming the movements of the probe in the longitudinal direction (X-direction), which is essentially perpendicular to the direction of the tip (Z-direction), into corresponding acceleration data. A second integrator that performs a double integration of the movements of the second acceleration transducer with respect to time and thus transforms the movements into longitudinal movement data, is connected in series with this second acceleration transducer. In this context, the term xe2x80x9cmovementxe2x80x9d refers to a movement of the probe normal to the measuring direction (Z-direction). This movement can be arbitrarily realized during a measuring process carried out with the probe. With known probes, this movement can be realized with a feed unit, the speed of which does not have to be constant as it was with the case with feed units known thus far. On the contrary, a significant advantage of the invention is that the movement over the surface to be sensed can also be realized manually, i.e., the speed of the movement need not be constant. The actual progression of the movement and consequently the sensed distance is, according to the invention, subsequently calculated by carrying out the aforementioned double integration. Since the acceleration data of the first acceleration transducer are also integrated twice as a function of time analogous to the movement data of the second acceleration transducer, the measuring movements, i.e., the respectively measured height values, are consequently assigned to the respective locations of the probe during its movement in the longitudinal direction (X-direction) such that the height progression of the surface of the workpiece is precisely determined.
According to a practical, additional refinement of this embodiment of the invention, reproduction means are provided, to which the longitudinal measurement data and the longitudinal movement data are fed, such that they are able to reproduce the excursions of the probe tip in the direction of the tip (Z-direction) as a function (z (x)) of the movement of the probe tip in the longitudinal direction that is normal (X-direction) to the direction of the tip (Z-direction). In this case, the reproduction means may consist of a picture tube or a paper tape, on which the measurement data is displayed as a function of the longitudinal movement data.
According to a practical additional refinement of this embodiment of the invention, it is proposed that a third acceleration transducer be provided that transforms lateral movements (y direction) of the probe perpendicular to the direction of the tip (Z-direction) and perpendicular to the longitudinal direction (X-direction) into corresponding lateral movement data, with a third integrator being provided that performs a double integration of the lateral acceleration data as a function of time, and thus, transforms the lateral acceleration data into corresponding lateral movement data which is fed to the reproduction means, in such a way that the topography of the surface sensed by the probe tip is produced by the reproduction means. It is thus possible to move the probe over the surface to be sensed in arbitrary directions normal to the direction of the tip (Z-direction). In this case, the probe travels on new sensing paths during each movement and the topography of the sensed surface is obtained if the density of the these sensing paths is sufficiently high.
In practical embodiments, the integrators which perform double integration of the signals of the acceleration transducers as a function of time are formed by two individual integrators connected in series.
The data delivered by the acceleration transducers may consist of analog data, in which case analog/digital converters are connected in series with the acceleration transducers. The output signals of these analog/digital converters are doubly integrated as a function of time by digital integrators connected in series. As mentioned previously, bandpass filters may be arranged ahead of the analog/digital converters in order to filter out certain frequency ranges, e.g., frequency ranges that correspond to the shape, undulations, or roughness of the surface.
As mentioned previously, the reproduction means may be realized in the form of a picture tube or a writing device, e.g., a chart recorder.
According to the invention, the probe tip is connected without rotational play to the first acceleration transducer. Depending on the type of construction of the acceleration transducer, this means that the mass of the acceleration transducer must be moved by the probe tip. During fast sensing movements, correspondingly high accelerations can occur and subject the probe tip to high stress that results in correspondingly high wear. In light of this, it is practical to connect the probe tip to the first acceleration transducer in such a way that it can be replaced. Naturally, it would also be conceivable to provide the probe tip with different tip radii such that the probe tip only carries out more significant excursions, e.g., excursions that correspond to the undulations or the shape of the surface. Consequently, high accelerations and the associated high wear of the probe tip are prevented.
It is practical to provide a damping means which damp the movements of the first acceleration transducer and consequently suppress natural oscillations or resonances.
The first and the second acceleration transducer can be arranged in a common housing together with the first and the second integrator and the reproduction means, with the probe tip protruding out of said housing. Consequently, it is possible to guide the housing manually over the surface to be sensed in such a way that the probe tip glides over the surface. The height contour of the sensed track on the surface then appears on the reproduction means.
In this embodiment, the housing preferably is in the form of a pen, with the probe tip protruding from the tip of the housing. Thus, when sensing the surface, the probe behaves as if a line were drawn on the surface of the workpiece with a pen. During this sensing process, the characteristics of the surface of the workpiece, i.e., the surface contour, the undulations, or the roughness, depending on the filtering process, appears on the display.
According to another embodiment of the basic idea of the invention, the rotational accelerations or rotational speeds of the probe arm are evaluated, with the probe tip being situated on said probe arm. The rotational angles are then determined from the rotational acceleration data by carrying out a double integration as a function of the time, with the excursions of the probe tip being calculated therefrom. Once the rotational speed is determined, the rotational angles are determined by carrying out a single integration as a function of time and calculating the excursions therefrom. Here, the sensing movement (in the X-direction) is uniformly linear.
The basic idea of invention can also be practically realized in such a way that a first acceleration sensor, the sensing direction of which lies in the pivoting plane of the probe arm, is arranged on the probe arm, where this first acceleration sensor delivers a first output signal a that is fed to a computer that multiplies the first output signal a by the radius r that represents the distance between the probe tip and the pivot bearing. Means for realizing a uniform linear movement of a base body that holds the probe arm are provided. Due to this uniform linear movement, the first acceleration sensor is not subject to any accelerations, i.e., no output signal is generated. This output signal is generated due to the fact that the effect of the gravitational acceleration on the acceleration sensor changes during an excursion of the probe arm, with the acceleration sensor delivering an output signal that depends on the inclination of the acceleration sensor arranged on the probe arm relative to the direction of the gravitational acceleration. Since the angle of the excursion of the probe arm during the sensing of a surface by the probe tip is a function of the radius r that represents the distance between the probe tip and the pivot bearing of the probe arm, a value for the movement of the probe tip in the direction of the tip (Z-direction) can be determined by taking into consideration the radius r.
In this case, it is advantageous if the sensing direction extends parallel to the direction of the tip (Z-direction) and the linear movement of the base body extends parallel to the earth""s surface, such that the output signal a of the first acceleration sensor corresponds to the sine of the angle of inclination a of the probe arm relative to the earth""s surface. If the angles of inclination are not excessively large, a primarily linear dependence between the angle of inclination and the excursion of the probe tip exists under these circumstances.
A particularly practical additional refinement of this embodiment of the basic idea of the invention is characterized by the fact that a second acceleration sensor, the sensing direction of which forms an angle of 90xc2x0 with the first acceleration sensor in the pivot plane of the probe arm, is provided, where this second acceleration sensor delivers a second output signal b. The angle xcex1 can then be determined from these two output signals a and b from arctan a/b, with the excursion of the probe tip z then being determined from r sin xcex1. Consequently, in this embodiment of the basic idea of the invention, it is not necessary to move the probe in a certain direction or to maintain a certain position of the probe relative to the direction of gravitational acceleration.
The acceleration sensors used in realizing the invention are generally known. For example, they contain a small weight that is suspended by springs, with the excursion of said weight due to accelerations being measured capacitively.
The invention is described in greater detail below with reference to the figures.

Probe for sensing the characteristics of a surface of a workpiece