The present invention is an acetabular cup having at least one polyaxial locking screw for anchoring the cup in the desired bone site. The assembly includes an acetabular cup having at least one through hole having both threaded and tapered portions, into which holes a two-piece interlocking coupling element and a bone screw having a semi-spherical head may be inserted. The two-piece coupling element, including slideably joined socket and cap portions, is mounted about the semi-spherical head of the bone screw, which is inserted into the through hole and into the bone. The head of the screw is polyaxially mounted in the socket portions and as such may be inserted into the bone at a variety of angles. The socket portion of the coupling element has slots which permits crush locking of the head of the screw once the socket seats and is forceably driven into the tapered portion of the hole. The cap portion is threaded so is may be advanced into the inner portion of the hole, thereby further locking the coupling element into the hole, and applying an additional driving force against the socket portion to crush lock the screw head at the selected angle relative to the cup.

1. Field of the Invention
This invention relates generally to a replacement hip implant assembly, and more specifically to an acetabular cup having a plurality of tapered holes therein for receiving polyaxial locking screws and coupling elements, such that the screws may be inserted into the adjacent bone at a wide range of angles.
2. Description of the Prior Art
Hip implant devices, which are utilized to replace corrsponding degenerated joints, generally include an outer metal cup (acetabular cup), and inner polymer or ceramic cup, a metal or ceramic ball, and a femoral post. The outer metal cup is implanted into the acetabulum (the socket portion of the pelvis), and secured therein by a variety of means, some of which are described hereinbelow. The inner polymer or ceramic cup seats within the outer metal cup and has a smooth semi-spherical interior conformation for receiving the metal or ceramic ball. The ball is smooth so as to provide low-friction polyaxially rotatability within the semi-spherical interior of the inner cup. The ball is also coupled to the top of the femoral post, which extends into the top of the femur to complete the coupling of the hip to the femur, while permitting rotation of the artifial joint.
There are a number of prosthetic hip devices which have been disclosed in the art which include the elements set forth above in various embodiments. The various embodiments disclose a spectrum of means for securing the acetabular cup to the pelvis. Some teach integral projections extending from the exterior surface of the cup-shaped body which provide anchoring for the element within the surrounding bone. European Patent Application No. 13,863, published on Jun. 8, 1980 describes such a device. The cup of this reference is anchored to the bone by a central pin and a number of other pins distributed over the surface of the cup. The pins have sawtooth notches along their length and are inserted into pre-drilled holes in the bone. Similarly, European Patent Application No. 211,169 published Feb. 25, 1987, discloses an acetabular cup which includes an external boss protruding from the outer surface of the cup to fit into a pre-drilled hole in the acetabulum.
An advance over fixed and integral anchoring projections is illustrated in U.S. Pat. No. 4,828,565 wherein the acetabular shell includes a pair of outwardly projecting elements which are fixed, but through which screws may be passed to further secure the cup in the bone.
The use of screws alone to anchor the acetabular cup in the surrounding bone is described in U.S. Pat. Nos. 3,939,497 and 4,685,923 in which a series of radially arranged pegs may be selectively projected outwardly through the wall of the cup into the surrounding bone.
In each of the devices described above, the integral anchoring projections and/or the selectively introduceable screws, the entrance angles of the securing means are rigidly predetermined. As it is desirable to provide the surgeon with the freedom to choose the entrance angle of the screw to best suit the individual conformation of the surrounding bone on a patient-by-patient basis, U.S. Pat. No. 4,792,337 provides an acetabular cup having countersunk holes and screws having rounded heads, such that the orientation of the screws may be varied with respect to the cup and each other.
While it is a substantial gain over the previous designs to provide for variability in screw entrance angle, a common concern with screws being implanted into bone is that the screws may dislocate and begin a process known as "pull-out". This is an especially important problem in conjunction with acetabular cups, wherein dislocated screws often impede the rotational motion of the device and/or provide a wearing impetus to erode the low friction surfaces at the motion interface.
There are no presently available screw plate assemblies which present a flush surface and provide for means of preventing both screw pull-out from the bone and screw backout, while simultaneously providing for a wide range of angulation for the bone screws.
It is therefore, an object of the present invention to provide a new and novel acetabular cup and anchoring screw design which allows for polyaxial entrance of the screw into the surrounding bone.
It is also an object of the present invention to provide an orthopaedic implant which has a simple and effective mechanism for locking the bone screw to the acetabular cup.
Other objects of the present invention not explicitly stated will be set forth and will be more clearly understood in conjunction with the descriptions of the preferred embodiments disclosed hereafter.

Acetabular cup having capped polyaxial locking screws


Methods of treating subterranean zones and viscous aqueous fluids containing xanthan biopolymer gelling agent and a combination crosslinker and delayed breaker are provided. A viscous cross-linked aqueous treating fluid of the invention comprises water, a xanthan polymer gelling agent, and a combination cross-linker and delayed breaker for said xanthan biopolymer gelling agent.

1. Field of the Invention
The present invention relates to methods of treating subterranean zones in formations penetrated by well bores with viscous cross-linked aqueous treating fluids that comprise water, a xanthan biopolymer gelling agent and a combination cross-linker and delayed breaker.
2. Description of the Prior Art
Viscous aqueous treating fluids are used in a variety of operations and treatments in oil and gas wells. Such operations and treatments include, but are not limited to, well completion operations, production stimulation treatments formation permeability conformance control treatments and the like.
An example of a well completion operation involving the use of high viscosity aqueous treating fluids is gravel packing. In gravel packing operations, solid particles referred to in the art as gravel, are carried to a subterranean zone in which a gravel pack is to be placed by a viscous cross-linked aqueous treating fluid. That is, particulate gravel material such as sand is suspended in the viscous cross-linked aqueous treating fluid at the surface and carried to the subterranean zone in which a gravel pack is to be placed. Once the particulate gravel material utilized is placed in the zone, the viscous cross-linked aqueous treating fluid, also referred to as a carrier fluid, breaks into a low viscosity fluid. The gravel pack produced functions as a filter to separate formation solids from produced fluids while permitting the produced fluids to flow into and through the well bore.
An example of a production stimulation treatment utilizing a viscous cross-linked aqueous treating fluid is hydraulic fracturing. That is, a viscous cross-linked aqueous treating fluid referred to in the art as a fracturing fluid, is pumped through the well bore into a subterranean zone to be stimulated at a rate and pressure such that fractures are formed and extended into the subterranean zone. At least a portion of the fracturing fluid carries solid particles such as sand, referred to in the art as proppant, which is carried into the formed fractures. The particulate proppant material is suspended in the viscous cross-linked aqueous fracturing fluid so that the particulate proppant material is deposited in the fractures when the fracturing fluid is broken, i.e., reduced to a low viscosity fluid. The particulate proppant material functions to prevent the formed fractures from closing whereby conductive channels are formed through which produced fluids can flow to the well bore.
The viscous cross-linked aqueous treating fluids utilized heretofore have been viscosified by combining a gelling agent with water. In order to increase the viscosity of the gelled water so that the treating fluid formed is capable of carrying particulate gravel material or particulate proppant material, the gelling agent in the water has been cross-linked by combining a cross-linking agent with the gelled water. In order to break the viscous cross-linked aqueous treating fluid after it has been placed in a subterranean zone, a separate delayed breaker has also been combined with the viscous cross-linked aqueous treating fluid. A particularly suitable gelling agent which is often utilized in gravel packing or fracturing subterranean zones is xanthan biopolymer. In order to cross-link the xanthan biopolymer gelling agent in water, a cross-linking agent such as sodium borate has been added to the gelled water and in order to break the viscous cross-linked aqueous treating fluid formed, a separate delayed breaker such as sodium persulfate has been added to the viscous cross-linked aqueous treating fluid. While the use of separate cross-linking agents and delayed breakers with an aqueous treating fluid containing xanthan biopolymer gelling agent has achieved good results, the cross-linker and delayed breaker have been expensive and require the use of separate pumping and metering equipment. Thus, there is a continuing need for improved cross-linking agents and delayed breakers which are less expensive and require the use of less equipment, etc.

Methods of treating subterranean zones and viscous aqueous fluids containing xanthan and a combination cross-linker—breaker


Living cellular material is encapsulated or placed in a protective material (cell protector) which is biocompatible, biodegradable and has a three-dimensional form. The three dimensional form is incorporated into a matrix that maybe implanted in vivo, ultimately degrade and thereby by replaced by living cell generated material.

In a principal aspect, the present invention relates to a construct for protecting biologics (such as cellular materials, particularly living cellular materials) by use of three-dimensional protective structures for such biologics using generally non-reactive, three dimensional containment materials so as to enable use of such combinations in vivo and in vitro environments for growth and/or replacement of damaged or missing cellular structure such as bone.
The need for biomaterials has increased as the world population ages. Due to its chemical and crystallographic similarity to the carbonated apatite in human bones, hydroxyapatite has found applications. While sintered hydroxyapatite needs machining and is used in prefabricated forms, calcium phosphate cements can be molded as pastes and set in situ (Brown and Chow, A new calcium phosphate water setting cement, pp. 352-379 in Brown, Cements research progress, American Ceramic Society, OH, 1986; Ginebra et al., Setting reaction and hardening of an apatite calcium phosphate cement, J. Dent. Res. 76:905-912, 1997; Constantz et al., Histological, chemical, and crystallographic analysis of four calcium phosphate cements in different rabbit osseous sites, J. Biomed. Mater. Res. [Appl. Biomater]. 43:451-461, 1998; Miyamoto et al., Histological and compositional evaluations of three types of calcium phosphate cements when implanted in subcutaneous tissue immediately after mixing, J. Biomed. Mater. Res. [Appl. Biomater.] 48:36-42, 1999; Lee et al., Alpha-BSM(R): A biomimetic bone substitute and drug delivery vehicle, Clin. Orthop Rel. Res. 367:396-405, 1999). Calcium phosphate cement, referred to as CPC, is comprised. of a mixture of fine particles of tetracalcium phosphate [TTCP: Ca4(PO4)2O] and dicalcium phosphate anhydrous [DCPA: CaHPO4]. The CPC powder can be mixed with water to form a paste that can intimately conform to osseous defects with complex shapes and set in vivo to form a hydroxyapatite-containing implant. Due to its in-situ setting ability, excellent osteoconductivity and bone replacement capability, CPC is promising for a wide range of clinical applications.
The term "in-situ setting" or "self-hardening" or "moldable" refers to the paste being able to set or harden inside a bone cavity or in a mold and being able to be shaped or contoured; for example, the CPC paste can be placed into a bone cavity and harden when in contact with an aqueous medium (Matsuya et al., Effects of mixing ratio and pH on the reaction between Ca4[PO4]2O and CaHPO4, J. Mater. Sci.: Mater. in Med. 11:305-311, 2000; Takagi et al., Morphological and phase characterizations of retrieved calcium phosphate cement implants, J. Biomed. Mater. Res. [Appl. Biomater.] 58:36-41, 2001). U.S. Pat. Nos. 5,525,148, 5,545,254, 5,976,234, and 5,997,624 (Chow et al.) disclose methods for calcium phosphate cements including fillers and pore forming agents. Xu et al. suggest fiber reinforcement of calcium phosphate cement in "Reinforcement of a self-setting calcium phosphate cement with different fibers", J. Biomed. Mater. Res. 52:107-114 (2000) and in "Effects of fiber length and volume fraction on the reinforcement of calcium phosphate cement", J. Mater. Sci.: Mater. in Med. 12:57-65 (2001). Von Gonten et al. suggest a single sheet of mesh reinforcement for calcium phosphate cement in "Load-bearing behavior of a simulated craniofacial structure fabricated from a hydroxyapatite cement and bioresorbable fiber-mesh", J. Mater. Sci.: Mater. in Med. 11:95-100 (2000). However, in these studies, there has been no mention of incorporating living cells into CPC. Takagi et al. suggest the formation of macropores resulting from the dissolution of soluble fillers or pore forming agents in "Formation of macropores in calcium phosphate cement implants", J. Mater. Sci. Mater. in Med. 12:135-139 (2001). Chow reviews calcium phosphate cements in "Calcium phosphate cements: Chemistry, properties, and applications", Mat. Res. Symp. Proc. 599:27-37 (2000). Xu et al. incorporate fibers and pore forming agents in "Strong and macroporous calcium phosphate cement: Effects of porosity and fiber reinforcement on mechanical properties", J. Biomed. Mater. Res. 57:457466 (2001). Xu et al. use resorbable fibers in "Calcium phosphate cement containing resorbable fibers for short-term reinforcement and macroporosity", Biomaterials 23:193-202 (2002). Xu et al. use synergistic reinforcement to develop scaffolds in "Effects of Synergistic reinforcement on in situ hardening calcium phosphate composite scaffold for bone tissue engineering" Biomaterials 25:1029-1037 (2004). Xu et al. also develop fast-setting and anti-washout CPC in "Fast-setting and anti-washout calcium phosphate scaffolds with high strength and controlled macropore formation rates", Journal of Biomedical Materials Research 68A:725-734 (2004). However, in these studies there is no mention of mixing living cells into the CPC paste.
Cell culture studies were performed on CPC to investigate the biocompatibility of CPC (Simon et al., Preliminary report on the biocompatibility of a moldable, resorbable, composite bone graft consisting of calcium phosphate cement and poly[lactide-co-glycolide] microspheres. J Orthop Res 20:473-482, 2002). Cell culture was performed to investigate the biocompatibility of CPC-fiber composite by using osteoblast-like cells (Xu et al., Self-hardening calcium phosphate composite scaffold for bone tissue engineering. Journal of Orthopaedic Research 22:535-543, 2004), CPC-mesh composite (Xu et al., Self-hardening calcium phosphate cement-mesh composite: Reinforcement, macropores, and cell response. Journal of Biomedical Materials Research 69A:267-278, 2004), and fast-setting CPC composite (Xu et al., Fast-setting calcium phosphate-chitosan scaffold: Mechanical properties and biocompatibility, Biomaterials, in review, 2004). Cells were seeded onto the specimens surfaces. The cell attachment, live and dead cell staining, and cell viability were investigated for these compositions. However, in these studies, no cells were mixed into the CPC paste. The CPC specimens were set or hardened without any cells in them. The cells were subsequently attached to the surfaces of the already hardened specimens.
U.S. Pat. No. 4,353,888 (Sefton) discloses encapsulation of viable mammalian cells to form beads for introduction into a host body. U.S. Pat. No. 4,892,538 (Aebischer et al.) discloses in vivo delivery of neurotransmitters by implanted, encapsulated cells using a semipermeable membrane which permits the diffusion of the neurotransmitter while excluding viruses and antibodies. U.S. Pat. No. 6,132,463 (Lee et al.), U.S. Pat. No. 6,139,578 (Lee et al.), U.S. Pat. No. 6,277,151 (Lee et al.), and U.S. Pat. No. 6,544,290 (Lee et al.) disclose a poorly-crystalline apatitic calcium phosphate material seeded with cells for bone and cartilage growth, in vitro cell culture systems and cell encapsulation matrices. U.S. Pat. No. 6,143,293 (Weiss et al.) discloses in-direct pre-formed scaffolds that can be seeded with cells: U.S. Pat. Application 2004/0101960 A 1 (Schaefer et al.) discloses an injectable hydroxyapatite cement containing living cells as a bone substitute material. Simon et al. (Cell seeding into calcium phosphate cement, Journal of Biomedical Materials Research, 68; A:628-639, 2004) show cell encapsulation in alginate beads that are then mixed with a CPC paste. None of this prior art mentions the design of three-dimensional cell protectors of lattice-like structures, or zigzag or woven or curved structures, or three-dimensional web-like structures. Furthermore, none of this prior art mentions the development of cell protectors for two functions: (1) protecting the cells from the surrounding environment for a predetermined time period; (2) controlled formation of three-dimensional pore architectures when the cell protectors dissolve and concomitantly release the living cells into the highly-interconnected pore structures in the in-situ setting implant.
U.S. Pat. Application 2002/0055143 A1 (Bell et al.) discloses bone precursor compositions including an injectable calcium cement than can be conditioned with cells, preferably bone tissue cells. It does not mention the use of three-dimensional cell protectors/pore architecture builders. U.S. Pat. Application 2003/0019396 A 1 (Edwards et al.) discloses a porous cement which self sets to hydroxyapatite and has an interconnected porosity. It does not mention the mixing of cells into the cement paste. U.S. Pat. Application A1 2003/0099630 (DiBenedetto et al.) discloses a bioactive material using fibroin solutions and suspensions that is injectable and able to form pores, and can release compounds in a controlled manner to enhance growth and activation of cells. It does not mention the mixing of cells into the injectable composition and the use of cell protectors/pore architecture builders.
U.S. Pat. Application 2003/0206937 A 1 (Gertzman et al.) discloses a malleable bone putty including a bone powder mixed in a hydrogel carrier. U.S. Pat. Application 2004/0062809 A1 (Honiger et al.) discloses porous biocompatible polymers in the form of hydrogels with a three-dimensional structure and communicating cells. Its three-dimensional structure refers to the structure of the porous implant as a whole; it does not refer to the formation of the pores alone. It does not mention the use of cell protectors/pore architecture builders incorporated inside an in situ implant matrix material.
U.S. Pat. Application 2004/0101518 A1 (Vacanti et al.) discloses a hydrogel-cell composition with a support structure having a predetermined shape that corresponds to the shape of a desired tissue. It does not use the hydrogel to protect the cells and form pore structures in the final implant. Neither does it mention the use of cell protectors and pore architecture builders that are incorporated inside an in situ implant matrix material.
U.S. Pat. Application 2004/0131678 A1 (Burger et al.) discloses a water based bone cement comprising a slow release bone growth factor and a fast release antimicrobial agent. U.S. Pat. Application 2004/0137032 A1 (Wang) discloses combinations of calcium phosphates, bone growth factors, and pore-forming additives as osteoconductive and osteoinductive composite bone grafts. It relates to the degradation of polymer microspheres as porogens leading to macropores that facilitate the growth of osteoblasts into the bone grafts. The cells are grown into the pores of the graft after the paste setting; the cells are not mixed into the paste prior to the paste setting. In this application the cells attach to a set and hardened surface. Furthermore, the polymer microspheres and/or water-soluble particles create pores that are sphere-like, discrete, or particle-shaped. It does not mention the use of cell protectors of three-dimensional lattice-like structures, or zigzag or woven or curved structures, or three-dimensional web-like structures. Nor does it mention the three-dimensional pore architecture builders where the cells are incorporated throughout the entire interior of the implant prior to the paste setting.
In conclusion, in prior art, there has been no mention of methods of fabricating surgical moldable and self-hardening implants containing living cells prior to paste placement where said living cells are protected in three-dimensional cell protectors for a prescribed time period, said protectors then subsequently dissolve at a predetermined time to free the cells inside the implant and concomitantly form three-dimensional pore architectures as cell and nutrient passageways throughout the entire interior of the implant.
Furthermore, there has been no mention in prior art of the design of cell protectors/pore architecture builders of three-dimensional lattice-like structures, zigzag or woven or curved structures, or three-dimensional web-like structures inside surgically placed implants. These structures serve two important functions: (1) protecting the cells, for a controlled period of time, from any undesirable environment including mechanical damage, pH changes, ion activities, and excessive temperature changes during paste setting; and (2) at a prescribed time, creating engineered three-dimensional pore architectures as cell nutrient and communication passageways throughout the implant.
In addition, in prior art, there has been no mention of using three-dimensional cell protectors/pore architecture builders inside a surgical moldable and self-hardening implant, with three-dimensional cell protectors/pore architecture builders having designed sizes, effective diameters, interconnectivity sizes, and degradation rates matching the applications, so that the cells can be released and pores created at a controlled time or at graded times.

Three dimensional cell protector/pore architecture formation for bone and tissue constructs


This invention deals with an advanced Real-time Grid Monitoring System (RTGMS) suitable for both single-phase and three-phase electric power systems. This invention provides an essential signal processing block to be used as a part of complex systems either focused on supervising and diagnosing power systems or devoted to control power processors interacting with the grid. This invention is based on a new algorithm very suitable for real-time characterization of the grid variables under distorted and unbalanced grid conditions. The main characteristic of this invention is the usage of a frequency-locked loop, based on detecting the grid frequency, for synchronizing to the grid variables. It results in a very robust system response in relation to existing technique based on the phase-angle detection since grid frequency is much more stable variable than the grid voltage/current phase-angle, mainly during grid faults. Moreover, the algorithm supporting this invention is very efficient and can be implemented in regular industrial microprocessors. These features make the RTGMS object of this invention ideal to be applied in the control of distributed generation systems (DGS), flexible AC transmission systems (FACTS), power quality conditioners (PQC) and uninterruptible power supplies (UPS). In all these systems, the fast and precise real time detection of the voltage and/or current sequence components under grid fault conditions is a crucial matter.

Information provided by a grid monitoring system is generally used to supervise the grid operating conditions, diagnose grid faults characteristics, synchronize power converters to the grid, calculate power flows, translate state variables of complex systems into synchronous reference frames, and calculate current and voltage references of power converters operating under generic grid conditions.
Regardless of the technique used in the monitoring system, amplitude, frequency and phase of the monitored variables must be obtained in a fast and accurate manner. Additionally, when the monitoring system is applied to a multi-phase networks preferable three phase grid, sequence components should be rapidly and precisely detected as well, even if the utility voltage is distorted and unbalanced. It is worth to remark that a real-time monitoring system should be based on a simple algorithm, with a low computational burden, which can be computed in each sampling period.
Grid monitoring can be performed by assuming a constant and well know value for the utility frequency. This approach makes calculations simple but gives rise to detection errors when frequency differs from its rated value. It is a common incident in micro-grid and weak grids, with widespread usage of distributed generators, working under faulty conditions. The most extended technique used for achieving a frequency-insensitive grid monitoring is using a Phase-Locked Loop (PLL). Regarding three-phase systems, considered as the most general case of grid monitoring, the following real-time monitoring systems based on the usage of some kind of PLL has been reported in the literature:
Monitors based on the Synchronous Reference Frame (SRF-PLL) [1] are broadly used in measurement and control systems. However, as reported in the literature [2], the SRF-PLL gives rise to unacceptably deficient results in presence of the voltage imbalance.
Monitors based on the Decoupled Double Synchronous Reference Frame (DSRF-PLL) [3] are able to estimate the positive- and negative-sequence components at fundamental frequency under unbalanced grid conditions. However the DSRF-PLL should be implemented in a high performance digital signal processor because of its notable computational cost. This constraint complicates its application in the detection of multiple harmonic components.
Monitors based on the single-phase Enhanced Phase-Locked Loop (EPLL) [4] achieve the isolation of the positive- and negative-sequence components by means of the usage of frequency adaptive single-phase notch filters [5] and the instantaneous symmetrical components method on the a-b-c reference frame [6]. The EPLL-based GMS could be applied under unbalanced grid conditions, however its response is slow and its computational burden is so high since four singe-phase EPLLs are necessary to implement a three-phase application. Moreover, its single-phase origin makes the GMS sensible to the effects of zero-sequence components in the grid voltage.
Monitors based on the Dual Second Order Generalized Integrator (DSOGI-PLL) [7] are also able to estimate the positive- and negative-sequence components under unbalanced grid conditions and its computational cost is smaller than earlier approaches.
All the previously presented grid monitoring techniques come from the evolution of the conventional single-phase PLL technique and different approaches have applied in order to make them robust enough for detecting sequence components in three-phase systems under generic unbalanced and distorted grid conditions. Consequently, all of these techniques have a common characteristic, namely, the monitoring algorithm is based on the detection of the phase-angle of the variable to be screened.
WO 02/091578 concerns a new structure for phase-locked loop (PLL) system. As with conventional PLLs, this invention consists of phase detection, loop filter and voltage-controlled oscillator units. An alternative phase detection structure, inspired by concepts from adaptive filtering and dynamical systems theory, is presented which substantially enhances the performance of the loop in terms of stability and dynamic performance. Presented phase detection scheme obviates the need for sophisticated loop filters, so much so that a first order filter suffices for most applications. In addition to the normal function of a PLL, the present system directly generates estimates of the amplitude, phase and frequency of the input signal. This feature extends the range of applications of the system beyond well-known applications of PLL in various disciplines of electrical.
US 2005/0231871 concerns a Three-phase Power Signal Processor (TPSP) is disclosed for general three-phase power system applications. The TPSP is developed based on the concepts from adaptive filter and dynamical systems theories. The structure of the TPSP is unified as it provides a multiplicity of the signals and pieces of information without the need to change, modify, or enhance the structure or to impose excessive computational time or resource requirements. The presented TPSP receives a set of three-phase measured signals, which can be voltage, current, magnetic flux, etc, and provides (1) the instantaneous and steady-state symmetrical components, (2) the fundamental components, (3) the peak values (magnitudes) of the symmetrical components, (4) the frequency and its rate of change, (5) the synchronization signal(s) and zero-crossing instants, (6) the phase-angles of the symmetrical components, and (7) the disturbance signatures. Two or more TPSP units, when properly augmented, further provide (8) the individual harmonic components, (9) the inter-harmonics, (10) the instantaneous real and reactive current components, (11) the total harmonic distortion, dc-offset, and power factor. The TPSP can serve as the building block for various signal processing requirements encountered in the context of power system applications including power systems control, protection, monitoring, and power quality.

Advanced real-time grid monitoring system and method


A head mountable arrangement assists a subject to acquire spatial information about a surrounding environment by receiving gaze data from an eyetracker and spatial data from a distance sensor respectively. The gaze data describe an estimated point of regard of the subject, and the spatial data describe a distance between a reference point and an object in the surrounding environment. A feedback signal is provided, which indicates a distance from the subject to said object in the surrounding environment. The feedback signal is generated based on the estimated point of regard and the spatial data, and may reflect the distance to a surface element of an object that intersects a straight line between an eye-base line of the subject and the estimated point of regard, which surface element is located closer to the eye-base line than any other surface element of the objects in the surrounding environment along said straight line.

Eye/gaze tracking is the process of measuring the motion and/or positioning of an eye relative to the head, or the point of gaze. An eyetracker is a device for measuring eye positions and eye movement. Eyetrackers are used in many different applications.
There are various methods for measuring eye movement. The most popular variant uses video images from which the eye position is extracted. Other methods use search coils, or are based on the electrooculogram. Originally, eyetracking technology was used in research on the visual system, in psychology, in psycholinguistics, marketing and in product design. Today, we see an increasing use of eyetrackers as input devices for human-computer interaction in various kinds of devices and apparatuses from smartphones to aircrafts. Many times, an eyetracker is an efficient means of interaction for a person who has reduced ability to speak and/or is unable to enter computer commands via conventional interfaces.
US 9,185,352 describes systems and methods that relate to a user providing input to a computing device using eye tracking from a mobile position. Here, a scene camera is mounted to the user so that the system collects image information related to where the user is looking. An indication is provided on a monitor of the computing device, or other field of view, to signify the presence and location of an identifying region of the monitor or field of view. An eye camera mounted to the user collects image information of the user's eye relating to a direction of gaze of the eye. When the direction of gaze of the user's tracked eye intersects the identifying region of the monitor or field of view, suitable eye tracking methods for controlling a computing device may be used to send instructions to the computing device.
US 2015/0049012 shows a method, an apparatus and a computer program product that provide feedback to a user of an augmented reality (AR) device having an optical see-through head mounted display (HMD). The apparatus obtains a location on the HMD corresponding to a user interaction with an object displayed on the HMD. The object may be an icon on the HMD and the user interaction may be an attempt by the user to select the icon through an eye gaze or gesture. The apparatus determines whether a spatial relationship between the location of user interaction and the object satisfies a criterion, and outputs a sensory indication, e.g., visual display, sound, vibration, when the criterion is satisfied. The apparatus may be configured to output a sensory indication when user interaction is successful, e.g., the icon was selected. Alternatively, the apparatus may be configured to output a sensory indication when the user interaction fails.
Thus, different technical solutions exist that identify a user's point of regard and provide feedback in the form of visual display, sound and vibration regarding the user's interaction with an apparatus.

Method, computer program and head mountable arrangement for assisting a subject to acquire spatial information about an environment


An electronic component module includes a semiconductor package having a first surface provided as a mounting surface and a second surface opposing the first surface, and including a semiconductor chip, a component package having a first surface facing the second surface of the semiconductor package, and a second surface opposing the first surface of the component package, the component package including a passive component, and a connector disposed on the second surface of the component package and having a connection surface configured to be mechanically coupled to an external device, the connector including a plurality of connection lines arranged on the connection surface.

The present inventive concept relates to an electronic component module including a semiconductor chip.
As mobile displays become larger, there is a growing need for an increase in battery capacity. As battery capacity increases, the area occupied by a battery increases. Therefore, it is necessary to reduce the size of a printed circuit board (PCB) provided as a main board. On the other hand, in response to such a demand for a reduction in size, modularization is required in consideration of the mounting area of various components, for example, passive components, as well as semiconductor packages.

Package-on-package and package connection system comprising the same


In a method for creating a virtual keyboard, multiple intersections formed as a honeycomb structure are set on a plane. A selected type of virtual keyboard is acquired according to a command input by a user. A number of keys according to the selected type of virtual keyboard are calculated to acquire intersections corresponding to the number of the keys from the plane. The keys are arranged to form a keyboard plane of the virtual keyboard. A standard difference of step lengths from a center key of the keyboard plane to the other keys is calculated. The virtual keyboard is displayed on a screen of a display device, in event the keyboard plane is determined available according to the calculated standard difference. Then the user can operate the virtual keyboard with a remote control device to input characters.

At present, a user of a set-top box (STB) or an internet protocol television (IPTV) without a standard keyboard may operate a virtual keyboard with a remote control device to input characters. The user should press directional control buttons of the remote control device to select keys corresponding to the characters. However, the present virtual keyboard is quadrate. If the keys corresponding to the characters are far away from each other, the remote control device buttons must be pressed many times. For example, if the user wants to input a word "WORLD", he/she should press the remote control device 29 times.

Device and method for creating virtual keyboard


An FPGA architecture offers logic elements with direct connection to neighboring logic elements and indirect connection through a routing matrix. A logic element and a portion of the routing matrix are formed as part of a tile, and tiles are joined to form arrays of selectable size. The routing matrix includes routing lines which connect just from one tile to the next and routing lines which extend longer distances through several tiles or through the entire chip. This combination is achieved by the formation of individual tiles, all of which are identical.

Field programmable gate arrays (FPGAs) are well known in the art. An FPGA comprises an array of configurable logic blocks (CLBs) which are programmably interconnected to each other to provide a logic function desired by a user. U.S. Pat. No. 4,870,302, reissued as U.S. Pat. No. Re. 34,363, and incorporated herein by reference, describes a well known FPGA architecture. Other publications, such as U.S. Pat. No. 4,758,745, U.S. Pat. No. 5,243,238, and published application WO 93/05577, also incorporated herein by reference, describe other FPGA architectures. The Xilinx 1993 Data Book entitled "The Programmable Logic Data Book", available from Xilinx, Inc., 2100 Logic Drive, San Jose, Calif. 95124, also incorporated herein by reference, describes several products which implement a number of FPGA architectures.
An FPGA is considered to be a general purpose device, i.e. being capable of performing any one of a plurality of functions, and is programmed by an end user to perform a selected function. Because of this design flexibility, a general purpose FPGA includes a significant number of wiring lines and transistors which remain unused in most applications. Moreover, FPGAs include overhead devices which facilitate programing of the FPGA to do the specified function. These overhead devices undesirably add area to the FPGA chip. To compensate for this overhead, it is commercially important to reduce the cost of the FPGA. One way to reduce the cost is to make the FPGA less general purpose, that is, to eliminate some configuration options which are less commonly used. However, this reduction in configuration options reduces the value of the FPGA to customers, who may not be able to predict which options will be needed. Therefore, a need arises to eliminate area while maximizing configuration options.

FPGA architecture with repeatable titles including routing matrices and logic matrices


A rotary bleed valve (10) for a gas turbine engine comprises a passage (11) connecting high pressure gases from a compressor to an exhaust and a valve member (12), the valve member (12) may be rotated within the passage (11)so as to vary or if necessary block the flow of compressor gases. The valve member (12) is shaped such that as the member (12) moves from a closed to an open position gas flows around the member (12) induces a torque on the member (12).

This invention relates to a rotary bleed valve assembly particularly but not exclusively for use with a gas turbine engine.
The concept of bleeding or recirculating a controlled variable proportion of compressor gases in a gas turbine engine is well-known. Usually a bleed valve assembly is utilised in the compressor gas flow which can allow bleeding of compressor gases to any desired degree. Hitherto, bleed valve assemblies for this purpose have utilised a valve member which moves rectilinearly across the gas glow to any necessary extent.
Problems arise with use of valve mechanisms which move rectilinearly in this way insofar as they can become easily seized or jammed due to the presence of pollutants in the compressor gases.
Also conventional bleed valves are typically pneumatically actuated and have response times of 200-500 ms. During this response time period, an excessive torsional load can be applied to the drive shafts of a gas turbine. The drive shafts therefore must be stressed accordingly, which increases the mass of the shafts and thereby the mass of the engine.


The present invention is a high voltage semiconductor switch that is formed from a chain of series coupled cascode circuits. In one embodiment, the switch may be a single-throw configuration coupled between an output and a direct current (DC) reference. In an alternate embodiment, the switch may be a double-throw configuration such that the output is switched between either a first DC reference or a second DC reference, such as ground. Each cascode circuit may have clamp circuits to prevent over voltage during switching transitions. The series coupled cascode circuits may be formed using discrete components or on a silicon-on-insulator (SOI) wafer, which may have a Silicon Dioxide insulator layer or a Sapphire insulator layer.

Traditional semiconductor processes for integrated circuits may produce transistor elements capable of switching voltages on the order of about six volts; however, circuit requirements may have needs for switching voltages much larger, such as on the order of 100 volts. For example, a micro-electromechanical system (MEMS) switch may require an actuation voltage between 60 volts and 100 volts. A traditional semiconductor wafer may have a device layer in direct contact with a substrate forming a P-N junction; therefore, multiple devices that are formed using the device layer are coupled to each other through the P-N junctions via the substrate, and voltages between the multiple devices are thus restricted to reverse voltage ratings of the P-N junctions to the substrate, which may be on the order of twenty to thirty volts.
A silicon-on-insulator (SOI) wafer uses an insulating layer between the device layer and the substrate; therefore, multiple devices that are formed using the device layer may be isolated from each other, which may support large voltages between devices. Thus, a need exists for a high voltage semiconductor switch formed using multiple semiconductor devices.

High voltage switch using multiple cascode circuits


Golf swing training devices are disclosed. The swing training devices can be used during practice, during play, or both. In one non-limiting embodiment, the swing training device can be used by the golfer to ensure that he or she stands the correct distance from the golf ball at address. In another non-limiting embodiment, the swing training device comprises an element that is sized and configured for making contact with at least a portion of a golfer's body during a golf swing to ensure that the golfer swings his or her arms properly on the backswing, the downswing, or both.

The golf swing starts out from an "address" position. The golf swing then involves a backswing and a downswing. One problem for average golfers is to stand the correct distance from the golf ball at address. Another problem is to ensure that the arms swing properly on the backswing and the downswing. It is believed to be desirable for golfers to swing their arms close to their body on the downswing portion of a golf swing. When a golfer is swinging, however, it is difficult to tell how well they are able to achieve this objective.
U.S. Pat. No. 6,293,875 B1 issued to Sanford is directed to a golf swing training aid that permits the user to verify that the face of the golf club has not been inadvertently rotated during the backswing and/or the downswing of a golf swing. The Sanford device consists of a planar flag portion that is attached to the end of a stem portion. The stem portion is fit into the vent hole of the grip on the end of the golf club. The Sanford patent states that the swing training aid described therein can be made of metal, plastic, or another material having sufficient rigidity. When the Sanford device is on the golf club, the device is used to allow the golfer to check the position of their club face by looking at the flag portion of the device. The object is to allow the golfer to check the club face orientation without rotating his or her head. The Sanford patent teaches nothing about providing a mechanism for training golfers to position their arms and/or hands a certain distance from their body before or during their swing.
Thus, there is a need to provide improved and different types of golf swing training devices.


Network node (110), and method (300) in a network node (110), for load control in a cell (130) in a wireless communication system (100). The method (300) comprises starting an interference cancellation process, for reducing interference between uplink signals, estimating an interference cancellation gain, relative to an interference reduced received uplink signal power resulting from the interference cancellation process, wherein the interference cancellation gain is estimated after the start of the interference cancellation process but before the interference cancellation process is completed. In addition, the method (300) comprises controlling the traffic load of the cell (130), by considering the estimated interference cancellation gain.

User equipments (UE), also known as mobile stations, wireless terminals and/or mobile terminals are enabled to communicate wirelessly in a wireless communication system, sometimes also referred to as a cellular radio system. The communication may be made e.g. between two user equipment units, between a user equipment and a regular telephone and/or between a user equipment and a server via a Radio Access Network (RAN) and possibly one or more core networks.
The user equipment units may further be referred to as mobile telephones, cellular telephones, laptops with wireless capability. The user equipment units in the present context may be, for example, portable, pocket-storable, hand-held, computer-comprised, or vehicle-mounted mobile devices, enabled to communicate voice and/or data, via the radio access network, with another entity, such as another user equipment or a server.
The wireless communication system covers a geographical area which is divided into cell areas, with each cell area being served by a network node, or base station e.g. a Radio Base Station (RBS), which in some networks may be referred to as "eNB", "eNodeB", "NodeB" or "B node", depending on the technology and terminology used. The network nodes may be of different classes such as e.g. macro eNodeBs, home eNodeBs or pico base stations, based on transmission power and thereby also cell size. A cell is the geographical area where radio coverage is provided by the network node/base station at a base station site and may also be referred to as a radio coverage area. One base station, situated on the base station site, may serve one or several cells by having one or several radio transmitters. The network nodes communicate over the air interface operating on radio frequencies with the user equipment units within range of the respective network node.
In some radio access networks, several network nodes may be connected, e.g. by landlines or microwave, to a Radio Network Controller (RNC) e.g. in Universal Mobile Telecommunications System (UMTS). The RNC, also sometimes termed a Base Station Controller (BSC) e.g. in GSM, may supervise and coordinate various activities of the plural network nodes connected thereto. GSM is an abbreviation for Global System for Mobile Communications (originally: Groupe Spécial Mobile).
UMTS is a third generation mobile communication system, which evolved from GSM, and is intended to provide improved mobile communication services based on Wideband Code Division Multiple Access (WCDMA) access technology. UMTS Terrestrial Radio Access Network (UTRAN) is essentially a radio access network using wideband code division multiple access for user equipment units.
The 3rd Generation Partnership Project (3GPP) has undertaken to evolve further the UTRAN and GSM based radio access network technologies, for example by developing the Long Term Evolution (LTE) and the Evolved Universal Terrestrial Radio Access Network (E-UTRAN).
High Speed Packet Access (HSPA) is a term encompassing two mobile telephony protocols, High Speed Downlink Packet Access (HSDPA) and High Speed Uplink Packet Access (HSUPA). HSPA extends and improves the performance of existing WCDMA protocols. It may here be mentioned that HSUPA also is known as Enhanced Uplink (EUL), in some literature, e.g. by 3GPP.
In the present context, the expressions downlink, downstream link or forward link may be used for the transmission path from the network node to the user equipment. The expression uplink, upstream link or reverse link may be used for the transmission path in the opposite direction i.e. from the user equipment to the network node.
In the HSPA uplink, the user equipments share the same time and frequency resource. When the Node B detects a signal from a specific user equipment, with a traditional RAKE receiver, the received power of the other user equipment and part of the received power of this specific user equipment, is regarded as interference to the specific user equipment at the Node B. In other words, the total received power at the Node B may be viewed as the cell load. When the total received power is high, the cell load is high. In practice, the uplink cell load is estimated in terms of the Rise Over Thermal (RoT) of the cell, which is the total received power divided by the thermal noise floor power. This may sometimes also be referred to as the noise rise, see FIG. 1A.
FIG. 1A illustrates the air interface load according to prior art. The pole capacity is the limiting theoretical bit rate of the uplink, corresponding to an infinite noise rise.
The noise rise may be seen as the total received power relative to the noise power within a cell. The noise rise is increasing with the number of user equipments and/or the radio traffic intensity within the cell. A general definition of noise rise in the linear domain is
                    η        =                                            I              tot                        N                    .                                    [        1        ]
The total received power, Itot, in a cell comprises uplink power from all user equipments in the own cell, Iown, uplink WCDMA radio link power from user equipments in the neighbour cells, Inei, as well as the thermal noise floor power N thusItot=Iown+Inei+N  [2]
Considering a user equipment at the cell border attempting to connect to the cell, the total received power from all user equipments at the Node B, i.e. within the cell served by the Node B, is interference to this user equipment. If the interference level is too high, the limited power of the user equipment may not be able to ensure a successful connection to the Node B. This results in a coverage problem. Therefore, a first main aim of load control of HSUPA is to control the total received power at the Node B to be below a target so that a user equipment at the cell border may connect to the cell when it wants. The target may depend on the cell size: a lower target for a larger cell size, vice versa.
Besides the rise over thermal target considering the coverage limit there is another limit which may be considered when setting the noise rise target, namely the stability limit. The reason is that if the load in the cell is too high the interference between user equipments will cause power rushes and in-stability of the system. To address the stability issue, current ideas include subtraction of estimates of the neighbour cell interference from the total power. This may not be perfectly true, however normally the inter-cell interference coupling between user equipments is a lot weaker than the intra-cell interference coupling between user equipments.
Therefore, the overall cell load must not exceed either the coverage or the stability limitations.
In order to control the total load in the cell to be below the rise over thermal target, and the stability noise rise target, a load estimator needs to estimate the load generated by each radio connection and the available scheduling headroom that Enhanced Dedicated Channel (E-DCH) traffic may use.
The load factor of one radio connection is defined asLi=Pi/Itot,  [3]where Pi is the received signal power from user channel i. The load factor estimation is the basis for load control. Therefore, for example the Dedicated Physical Control CHannel (DPCCH) load of the user equipment i isLci=Pci/Itot,where Pci is the received DPCCH power of the user equipment i. The scheduling headroom, or the maximum allowed Enhanced Dedicated Channel (E-DCH) load in the cell is thusLmax EDCH=Lmax RoT−Lothers−LnonEDCH=1−1/RoTtarget−Lothers−LnonEDCH,  [4]where Lothers is the summed load of the inter-cell interference and LnonEDCH is the summed load of the non E-DCH channels, for example DCH and High Speed (HS)-DPCCH.
                              L          nonEDCH                =                              ∑                          #                            nonEDCH                                                                    P              nonEDCH                        /                                          I                tot                            .                                                          [        5        ]
During scheduling, the scheduler may estimate the total E-DCH load with the allocated grant by summing the load factor of the E-DCH channels.
                              L          EDCH                =                              ∑                          #                            EDCH                                                                    P              EDCH                        /                                          I                tot                            .                                                          [        6        ]
The scheduler may also estimate the Enhanced Transport Format Combinations (E-TFC) grant that may eat up the available load room based on the E-DCH Dedicated Physical Data Channel (E-DPDCH) load factor. The E-DPDCH load factor of user equipment i with E-TFC j isLE-TFCj,i=PE-TFCj,i/Itot=Pci·βj/Itot where βj is the E-DPDCH to DPCCH power offset and is one by one mapped to the corresponding E-TFCj.
Therefore, suppose the available load room for user equipment i is Lavail, the suitable E-TFC (or corresponding power offset) may be calculated asβj=Lavail/(Pci/Itot),  [7]which may be referred to as load to E-TFC mapping.
The estimation of rise over thermal relies on the measurement of the total interference and knowledge of the thermal noise power floor.
To understand the desire to apply sophisticated estimation techniques to find the thermal noise power floor, it is to be noted that the signal reference point is at the antenna connector, by definition. The interference measurements are however obtained after the analogue signal conditioning chain, in the digital receiver. The analogue signal conditioning chain does introduce a scale factor error of about 1 dB (1-sigma) that is difficult to compensate for. Fortunately, all contributing interference powers are equally affected by the scale factor error so when the rise over thermal is calculated, the scale factor error may be cancelled as
                                                                        RoT                Digitalreceiver                            =                                                                            I                                      tor                    ,                    air                                                                    N                  Digitalreceiver                                                                                =                                                                            scaleFactor                  ×                                      I                                          tot                      ,                      antenna                                                                                scaleFactor                  ×                                      N                    Antenna                                                                                =                                                                            RoT                  Antenna                                .                                                                        [        8        ]
In order to understand the fundamental problem of neighbour cell interference when performing load estimation, note thatIneighbor+N=E└INeighbor(t)┘+E[N]+ΔINeighbor+ΔN,  [9]where E[ ] denotes mathematical expectation and where Δ denotes the variation around the mean. The fundamental problem may now be clearly seen. Since there are no measurements available in the network node that are related to the neighbour cell interference, a linear filtering operation may at best estimate the sum E└INeighbor┘+E[N]. This estimate cannot be used to deduce the value of E[N]. The situation is the same as when the sum of two numbers is available. Then there is no way to figure out the values of the individual numbers. This issue is analyzed rigorously for the rise over thermal estimation problem in equation [2] where it is proved that the noise power floor is not mathematically observable.
The rise over thermal estimation algorithm is depicted in FIG. 1B. It is described in detail in [3]. The main problem solved by the estimation algorithm may be the accurate estimation of the thermal noise floor N. Since it is not possible to obtain exact estimates of this quantity due to the neighbour cell interference, the estimator therefore applies an approximation, by consideration of the soft minimum as computed over a relative long window in time.
It is important to understand that this estimation relies on the fact that the noise floor is constant over very long periods of time, disregarding the small temperature drift.
The sliding window algorithm of the above section has the disadvantage of requiring a large amount of storage memory. This becomes particularly troublesome in case a large number of instances of the algorithm are needed, as may be the case when Interference Cancellation (IC) is introduced in the uplink.
Interference cancellation approaches for HSUPA, e.g., [5][6], are attractive for the purposes of achieving higher and higher uplink data rates. Typically, some form of iterative processing is employed in a multi-stage architecture. In each successive stage, interference is cancelled leading to improved detection of the desired signal(s). One such architecture for HSUPA is illustrated in FIG. 1C. In this exemplary architecture, the data channel for users 1 and 2 (E-DPDCH) is detected in a multi-stage fashion. These user equipments are referred to as the Multi-User Detection (MUD) user equipments.
The control channels for both the MUD user equipments and non-MUD user equipments (DPCCH, E-DPCCH, HS-DPCCH) are cancelled in various stages depending on when the control information is needed. For example, in order to detect the data channel, the E-DPCCH needs to be decoded, thus it is detected and cancelled in the first stage. The HS-DPCCH is detected, decoded, and cancelled in the second stage, since the information it carries is not critical to detecting the data channel. Delaying this channel to the second stage allows it to benefit from cancellation in the second stage. Similarly, the Physical Random Access Channel (PRACH) is detected in a later stage (e.g., stage-2, FIG. 1C) to allow it to benefit from interference cancellation (more on this below).
Note that only after the first stage will any signal benefit from the cancellation of other signals since the signals in the first stage are detected in parallel in the presence of the maximum level of interference. The block diagram shows the interference cancellation taking place in an "Antenna Buffer" indicated by the "Ant Buf" blocks. As such, the antenna buffer after each stage contains a "cleaned up" version of the original received signal. It is cleaned up in the sense that interference is cancelled.
As mentioned above, the PRACH is not detected until a later stage (e.g., stage-2 in FIG. 1C) to allow it to benefit from interference cancellation in earlier stages. Ideally, one would like to delay the detection of this signal as much as possible to maximize the benefit from interference cancellation; however, there is a limit due to the timing constraints on this channel set by the standard. There is a delay budget between the time the Random Access Channel (RACH) preamble is signalled by the user equipment and the time the user equipment received back an acquisition indicator (AICH) message indicating successful RACH detection. For this reason, the RACH detection is placed in stage-2.
The Random Access Channel is a shared channel that is used by user equipments in the cell e.g. for initial access to the network, without being scheduled.
FIG. 1C which may be a suitable trade-off between the interference cancellation benefit and the timing constraints. If the interference cancellation processing is very fast, then the RACH detection could be delayed further, thus increasing the benefit from interference cancellation without violating the timing constraints.
With interference cancellation between user equipments, to reach the Signal to Interference and Noise Ratio (SINR) target for a certain transport format, the required transmit power of a user may be reduced driven by the power control function. As a consequence, the load in the cell may be reduced, and more scheduling headroom may be left for the E-DCH traffic. Therefore, the cell throughput is expected to increase with interference cancellation.
Furthermore, further throughput gain could be expected from increasing the allowed cell load considering that the interference as experienced by the user equipment is no longer the total received air interface power at the Node B. The stability may be much better controlled with interference cancellation so that the load limit considering stability could be further released. Therefore, the cell load may be controlled based on the user experienced load after interference cancellation processing.
FIG. 1D illustrates the general principles of an interference cancellation process. When the transmission of a user equipment has been detected, or even decoded, the so obtained signal may be used to re-generate a model signal, a replica signal, that resembles the effect of the original transmitted signal of the user equipment e.g. at the antenna or at another point in the receiver chain. The creation of the signal always requires that the channel model is available, to capture the effect of the radio transmission from the user equipment to the base station. The model signal may then be subtracted from the received broadband signal. In case the model signal is accurate, then the effect of the user equipment on the uplink may be reduced. Since this signal is only interference for the other user equipment, the effect of the subtraction is that interference as seen by the user equipment is cancelled, hence the acronym interference cancellation.
Interference cancellation exists in several variants. As indicated above interference cancellation may be based on demodulated IQ samples. Another option is to base the cancellation on decoded symbols. The latter option has the advantage of a better performance since the coding gain is exploited to enhance the quality of the model signal. On the other hand the delay is increased, due to the time needed for the decoding step. An additional delay is a consequence of most practical interference cancellation variants, since a model signal may need to be created before cancellation may be performed.
Another distinction of interference cancellation algorithms may be between soft and hard algorithms.
Today, much of the discussion on how to implement interference cancellation is focused on the different architectures, described in the following sub-sections. This is because interference cancellation may in general be computationally complex and also cause a time delay, which may be somewhat different for different interference cancellation architectures, as e.g. the ones illustrated in FIG. 1E and FIG. 1F.
FIG. 1E illustrates a structure of Successive Interference Cancellation (SIC). The block diagram is shown for detected signals. As may be seen in FIG. 1E, the detected signal of the first user equipment is immediately used to improve the conditions for all other user equipments, then the detected signal of the second user equipment is used to improve the conditions for all other user equipments but the first user equipment, and so on. This means that interference cancellation gains are achieved already at stage 1, however the delay of each stage will be dependent on the detection time of each user equipment. The delay may hence depend on the number of (interference cancellation) user equipments.
FIG. 1F illustrates the principles of Parallel Interference Cancellation (PIC). In parallel interference cancellation interference subtraction is only performed between stages. The consequence is that the number of units for regeneration and subtraction become large. The delay is however fix, a fact that simplifies system design.
The previously known solutions further increase the cell load mainly based on the fact that with interference cancellation the stability between user equipments is improved. For a multi-stage interference cancellation process, the interference cancellation gain after the final interference cancellation stage is captured. This is proper with for example the clean-carrier case, which means no new user equipment will connect to this carrier. However, for a normal case, the coverage limit for load control needs to be handled as well.
For a multi-stage interference cancellation process, the channel that limits the cell coverage (e.g. PRACH) may not be able to get the full interference cancellation gain at the final interference cancellation stage. For example, considering the delay that may be tolerated, the PRACH may have to be detected at some intermediate interference cancellation stage rather than at the final stage, and if the load is controlled based on the final interference cancellation stage, there will be a coverage problem. However, there are no algorithms or concepts known in prior art that are able to address the load experience after said some intermediate interference cancellation stage rather than the final interference cancellation stage. Moreover, prior art always controls the load based on interference cancellation gain estimated at a fixed interference cancellation stage (e.g. the final stage), and this may either overestimate or underestimate the available coverage budget.
Furthermore, known solutions estimate interference cancellation gains only based on the total wideband received power before and after interference cancellation, which is inaccurate especially in a multi-cell cases, where there exists inter-cell interference. Moreover, different channels of a user equipment may experience different interference cancellation gain (e.g. the control channel may have less interference cancellation gain due to different handling scheme), this is currently not considered.


A downhole motor having an improved thread fastening structure is proposed. In the downhole motor, a thread structure disposed therein and having ridges formed at both end portions at a predetermined distance from ends is improved and the internal structures of a first coupler and a second coupler in which the end portions of the thread are respectively inserted and fastened are improved to correspond to the end portions of the thread, thereby being able to improve sealing ability.

In general, a directional motor is a drilling instrument that can bore while 3-dimensionally changing the route and direction to the target point under the ground and is generally used mainly in North America, but it is increasingly required to develop an independent technology even in our country due to an increase of the oil industry and construction f various pipelines.
As inventions related to a directional motor in the related art, Korean Patent Application Publication No. 10-2017-0005445, titled "mud motor transmission", Korean Patent Application Publication No. 10-2018-0052760, titled "steel alloy with high strength, high impact toughness and excellent fatigue life for mud motor shaft applications", and Korean Patent No. 10-1958139, titled "a mud motor having a power transmission" have been proposed and published.
In Korean Patent Application Publication No. 10-2017-0005445, titled "mud motor transmission", an invention related to an apparatus that includes a new coupling allowing for transmission of torsion energy and can substantially remove or reduce angular changes generated in input shafts by allowing for transmission torsion energy from one shaft to another shaft and receiving arrangements of eccentric or parallel offset shafts has been proposed; In Korean Patent Application Publication No. 10-2018-0052760, titled "steel alloy with high strength, high impact toughness and excellent fatigue life for mud motor shaft applications", an invention relates to a compound that enables deeper drilling by providing a strong shaft material having not only high impact toughness, but also an excellent rotation buckling fatigue lifespan has been proposed; and In Korean Patent No. 10-1958139, titled "a mud motor having a power transmission", an invention related to an apparatus that enables smooth power transmission by including a connector that has a cylindrical shape with open top and bottom and is installed between a driving shaft and a bit shaft such that the upper portion thereof is coupled to the driving shaft and the lower end thereof is coupled to a driven bearing groove formed on the inner surface of the bit shaft has been proposed.
However, according to these inventions in the related art, there is a problem that a small amount of mud that is delivered may leak due to poor coupling between a thread and another part or structural limitation, so Teflon tape is wound around the ridges of the thread and epoxy is applied to solve the problem, but in this case, there is a problem that costs are increased and the work process becomes complicated.
Therefore, it is required to develop an apparatus that can prevent leakage of mud due to poor coupling between a thread and another part or structural limitation and can prevent generation of costs and complication of the work process due to applying Teflon tape and applying epoxy.
The description provided above as a related art of the present invention is just for helping understanding the background of the present invention and should not be construed as being included in the related art known by those skilled in the art.

Downhole motor that improved thread fastening structure


A memory controller includes a clock generator to generate a first clock signal and a timing circuit to generate a second clock signal from the first clock signal. The second clock signal times communications with any of a plurality of memory devices in respective ranks, including a first memory device in a first rank and a second memory device in a second rank. The timing circuit is configured to adjust a phase of the first clock signal, when the memory controller is communicating with the second memory device, based on calibration data associated with the second memory device and timing adjustment data associated with feedback from at least the first memory device.

The timing of data communications between a memory controller and memory devices presents significant engineering challenges. For example, voltage and temperature variation during operating can cause a previous calibration to become obsolete. Frequent calibrations, however, cause system delays. Also, inclusion of a PLL or DLL on the memory devices is not desirable, due to power, die area, and system delay issues.
Like reference numerals refer to corresponding parts throughout the drawings.

This patent is subject to a terminal disclaimer.

Clock generation for timing communications with ranks of memory devices


A round bale carrier which picks up hay bales while moving in a direction perpendicular to a longitudinal end-to-end direction of a bale to be loaded onto the carrier, and a bale pick-up supported by the bale carrier. The bale pick-up comprises an open sided bale cradle including a cradle base located parallel along one side of the carrier when in a pick-up position and swingable in a horizontal plane through 90 degrees to a bale loading position relative to the carrier. First and second bale support arms are secured to the cradle base with the first bale support arm extending out at generally right angles to the cradle base an the second bale support arm being moveable at the cradle base between a bale receiving position generally perpendicular to the first bale support arm and a bale pick-up position generally parallel to the first bale support arm. The bale cradle also is liftable from the bale loading position to a bale delivery position projecting upwardly from the one side of the carrier. A control system is provided for the bale pick-up and this control system includes a first operating member which moves the second bale support arm, a second operating member which swings the cradle base and a third operating member which raises and lowers the cradle. The control system operates such tat after the first operating member moves the second bale support arm to the bales pick-up position, the third operating member raises the cradle sufficiently to elevate a bale int he cradle away form ground level before the second operating member swings the cradle to the bale loading position. The third operating member then continues to raise the cradle to the bale delivery position.

One form of carrier for transporting large, round bales of hay or other crops includes a bale support for carrying a row of bales arranged end-to-end in the direction of travel of the carrier. The carrier may be equipped with a pick-up for picking up a bale as the carrier moves to a position beside the bale and lifting the bale onto the bale support. The bale is then transported along the support so the receiving position on the support is available for receiving the next bale from the pick-up.
An apparatus for this purpose must travel in a direction across the path of travel of the baler that made the bale, because the longitudinal, end-to-end dimension of the bale is generally across the path of the baler, while it is in line with the bale pick-up path. This creates problems in many instances. For example, in a ditch the bale carrier cannot travel up across the ditch to pick up and load the bales. On a slope it is often undesirable to travel across the slope for reasons of carrier stability.
In some bale carriers of the type in question, there are two side-by-side bale supports for carrying side-by-side rows of bales. This type of carrier conventionally requires two pick-ups, one on each side of the carrier for supplying bales to the respective supports.

Quarter turn bale lift arm for round bale movers


The invention relates to a vehicle door (1) and to a method for the production thereof. The vehicle door comprises a supporting frame (11) with an opening (2). The supporting frame is joined to a body structure of the vehicle in a manner that permits it to move. The opening (2) is closed in an essentially moisture-proof manner by molding it with a curable compound while forming a supporting plate (10) for accommodating elements such as window lifters, loudspeakers (3) or the like. At least one guide rail for guiding a window pane (9), which can be displaced relative to the supporting frame, is provided for accommodating a lateral edge of the window pane in the supporting plate.

Vehicles doors are known which have a supporting frame provided with a central opening, said supporting frame being connected movably to a body structure of the vehicle (in the case of conventional automotive vehicle side doors via an articulation, in the case of small buses via rails). Such a door is described for example in the German patent application DE 101 26 250.
It is disadvantageous in such a known door with a supporting frame that individual components, e.g. for fixing the window winding mechanism or for mounting loudspeakers, door lock elements etc. on the supporting frame, need to be mounted with great complexity. In addition, it is disadvantageous that, within the supporting frame which normally is sealed inwardly by a door interior lining and outwardly by exterior panelling, no defined separation of the wet/dry region is given so that, with a movable window pane provided in the door, moisture penetration into sensitive components, such as e.g. loudspeakers, is possible in certain circumstances.
The object therefore underlying the present invention is to provide a vehicle door and a method for the production thereof, the production costs being low and a defined separation of wet and dry regions in the door interior being given in order to ensure long term quality.
This object preferably is achieved by the characterizing features of the present invention.

Vehicle door and method for the production thereof


The tree stand has a lower rectangular platform with an extended opening from the center to an outer edge of the platform for installation around a tree trunk. An upper platform provides a secure seating area. A plurality of support members are pivotally attached to the lower surface of the lower rectangular platform and have teeth on their lower end adapted for securing into the bark of a tree. The tree stand is further secured to the tree by a plurality of angle irons that are mounted at the center of the upper and lower platforms. Adjustable tension straps attach to the angle iron and tighten the platforms to the tree preventing vertical movement of the tree stand. The support members on the lower platform have a hook on the lower end opposite the teeth, and an adjustable tension strap that engages the hooks further tightens the support members against the tree.

1. Field of the Invention
The present invention relates to devices for concealing-observers and hunters from game animals, and more particularly to a tree stand with a shooting rail and a seat that is raised on a pole or tree and used from an elevated position.
2. Description of the Related Art
Deer hunting in North America dates back to when man first had and made weapons to hunt them. Besides the food value that deer offered early hunters, many items were needed for survival. Early deer hunters used the deer hides for many necessary items, such as moccasins, skirts, dresses, leggings, robes, blankets, archery quivers, straps, harnesses and many other essential items came from deer hunting.
While venison is still considered a delicacy by many people, most modern deer hunting takes the form of sport and recreational activity. There are various types of hunting, from bow and arrow hunting to a range of firearms, such as high-powered rifles or shotguns and muzzleloaders. Most states have special deer seasons that accommodate various hunting methods, in addition to the traditional deer-hunting season that usually occurs in the fall.
The most common method of hunting deer is from tree stands using bows or guns. A tree stand is a perch that may be attached to a tree, typically the tree trunk, for hunting and observing wildlife.
Branches and foliage in deciduous trees generally grow out, away from the trunk, providing natural cover for the hunter. Turkey hunters often use trees to hunt from as well, and bear hunting can also be done using tree stands.
Theoretically, a tree stand gives a hunter an advantage of not only being hidden so that he or she cannot be seen by the game animal, but the elevation also gives a much greater field of view than would otherwise be available to a hunter confined to the ground. A hunter positioned several feet up in a tree would have the potential of a full panoramic view of the area, thus greatly increasing the odds of a successful hunt.
Most tree stands do not fully exploit this potential, as a perched hunter is generally confined to a specific orientation relative to the tree and thus the hunter's maneuverability and field of view are somewhat inhibited. There is a need, therefore, for a tree stand that allows a hunter to maneuver freely, have a full field of view, and is safe and uncomplicated to install in a tree. Thus, a tree stand solving the aforementioned problems is desired.


The present invention discloses a method for in-situ cleaning a reactive ion etching (RIE) chamber after a silicon nitride etching process by maintaining a vacuum and a radial frequency power in the chamber while flowing a chlorine gas into the chamber at a sufficient flow rate. The chlorine gas cleaning step can be integrated into the process recipe for the etching process without significantly affecting the cycle time and the yield of the process.

In the fabrication of semiconductor integrated circuit (IC) devices, various structures such as insulation layers, metallization layers, passivation layers, etc., are formed or deposited on a semi-conducting substrate. It is a known fact that the quality of the IC devices fabricated is a function of the processes in which these structures are formed or deposited. The yield of an IC fabrication process, which in turn is a function of the quality of the device fabricated and a function of the cleanliness of the manufacturing environment in which the IC devices are processed.
The ever increasing trend of miniaturization of semiconductor IC devices occurred in recent years requires more stringent control of the cleanliness in the fabrication process or the processing chamber utilized in the process. This leads to a more strict control of the maximum amount of impurities and contaminants that are allowed in a process chamber. When the dimension of the miniaturized device approaches the sub-half-micron level, a minutest amount of contaminants can significantly reduce the yield of the IC manufacturing process. For instance, the yield of the process can be drastically reduced by the presence of contaminating particles during deposition or etching of films which leads to the formation of voids, dislocations or short-circuits resulting in performance and reliability problems in the IC devices fabricated.
In recent years, contamination caused by particles or films has been reduced by the improvements made in the quality of clean rooms and by the increasing utilization of automated equipment which are designed to minimize exposure to human operators. However, even though contaminants from external sources have been reduced, various contaminating particles and films are still generated inside the process chambers during the processing of semiconductor wafers. Some possible sources of contamination that have been identified include the process gases and liquids, the interior walls of the process chambers, and the mechanical wear of the wafer handling equipment. The chances of generating contaminating particles are also increased in processing chamber that are equipped with plasma enhancement. Various chemically reacted fragments are generated from the processing gases which include ions, electrons and radicals. These fragments can combine and form negatively charged particles which may ultimately contaminate a substrate that is being processed in the chamber. Various other materials, such as polymeric films may also be coated on the process chamber walls during plasma processing. The films may dislodge and fall from the process chamber walls when subjected to mechanical and thermal stresses such that they fall onto the wafers that are being processed.
A good example for illustrating chamber wall contamination is the etcher 10 shown in FIG. 1. Etcher 10 is a plasma etching chamber that is equipped with magnetic field enhancement generated by an upper rotating magnet 12 and a lower rotating magnet 14. The plasma etcher 10 includes a housing 16 that is typically made of a non-magnetic material such as aluminum which defines a chamber 20. A substrate holder 22 which is also a cathode is connected to a radial-frequency generator 24 which is in turn connected to a gas inlet or showerhead 26. The showerhead 26 also acts as an anode. A process gas 28 is supplied to chamber 20 through the gas inlet showerhead (or the manifold plate) 26. A semi-conducting substrate 30 to be processed is positioned on the substrate holder or cathode 22.
The semi-conducting substrate 30 is normally held against the substrate holder 22 by a clamp ring 32. During a plasma etching process, a semi-conducting wafer 30 heats up during the process and therefore must be cooled by a cooling gas from a cooling gas supply (not shown) such that heat can be transferred to a water cooled wafer holder 36. The function of the clamp ring 32 is also to hold the wafer 30 down against the pressure generated by the cooling gas. An exhaust port 34 which is connected to a vacuum pump (not shown) evacuates the chamber. During an etching process, the upper rotating magnet 12 and the lower rotating magnet 14 function together to provide a magnetic field inside the process chamber 20.
In a conventional cleaning process for a plasma etch chamber 10, a cleaning gas supply is first flown through the gas inlet port 26 into the chamber 20 and then, the RF generator 24 is turned on. This cleaning procedure is conducted after a predetermined number, e.g., between 100.about.500 wafers, have been processed in chamber 20. A plasma of the cleaning gas ions is formed in the space between the showerhead 26 and the wafer holder 32 to loosen the contaminating particles and films from the chamber walls and the upper electrode or showerhead 26.
In a silicon nitride etching process, it was discovered that when a wafer is coated with a photoresist layer, patterned and then placed in an etch chamber for a plasma etching process, the etchant gas flown into the chamber also etches the photoresist layer which is normally of a polymeric base. A byproduct of the photoresist layer when etched by the etchant gas is a fluorine-containing or Teflon-type polymer which deposits on the chamber walls and the upper electrode. When the polymeric contaminating film deposited on the chamber walls become too thick, the gravity and the mechanical stress generated by the pressure differential each time the chamber door is opened for loading or unloading loosen the polymeric films from the chamber walls. These contaminating films or particles dislodge from the chamber walls during a nitride film etching process onto the wafer surface. The contamination decreases the yield significantly since nitride etching is frequently used to define the activation regions in an IC chip.
FIGS. 2A.about.2D provides an illustration of the effect of such contamination. In FIG. 2A, a pre-processed semi-conducting substrate 40 which is coated with a silicon nitride layer 42 is provided. On top of the nitride layer 42, a photoresist layer 44 is deposited and patterned. During a subsequent etching process for the silicon nitride layer 42, a polymeric film 46 dislodged from the chamber walls falls on the surface of the wafer 40. The polymeric film 46 acts as a mask during the nitride etching process and as a consequence, the area covered by the polymeric film is not etched away during the nitride etching. This is shown in FIG. 2B.
In a subsequent processing step where a field oxide isolation (FOX) is grown, FOX does not grow in the area that is still covered by the silicon nitride. Therefore, only a very small field oxide 50 is grown. This is shown in FIG. 2C. For comparison, FIG. 2D illustrates a normally grown field oxide 52 without the polymeric film contamination problem. The problem in growing field oxide regions (or the lack of growth of a FOX region) is frequently known as a "FOX missing" defect.
The conventional chamber cleaning method which is carried out only after a large number of wafers have been processed in the chamber has been proven to be ineffective since many defective wafers can be produced in-between the two chamber cleaning procedures. Only a limited number of defect-free wafers can be produced after each chamber cleaning procedure is carried out.
It is therefore an object of the present invention to provide a method for in-situ cleaning of an etch chamber that does not have the drawbacks and shortcomings of the conventional cleaning methods.
It is another object of the present invention to provide a method for in-situ cleaning an etch chamber that can be integrated into the process recipe as part of the etching process.
It is a further object of the present invention to provide a method for in-situ cleaning an etch chamber capable of ensuring that each etching process is carried out in a clean chamber.
It is still another object of the present invention to provide a method for in-situ cleaning a RIE chamber after an etching process is conducted on a silicon nitride film deposited on a semi-conducting substrate.
It is another further object of the present invention to provide a method for in-situ cleaning of a RIE chamber by integrating a chlorine gas cleaning step into the process recipe.
It is yet another object of the present invention to provide a method for in-situ cleaning a RIE chamber which is used for silicon nitride etching process by a main etching step and an over etching step by incorporated a chlorine cleaning procedure as the third step of the etching process.
It is still another further object of the present invention to provide a method for in-situ cleaning a RIE chamber after a nitride film etching process is conducted in the chamber by integrating a chlorine cleaning step with the main etching step for the nitride film.

Integrated film etching/chamber cleaning process

Taiwan Semiconductor Manufacturing Co. Ltd.


An electroconductive paste comprising first copper particles having a specific surface area of about 0.15-1.0 m2/g, second copper particles having a specific surface area of about 0.5-2.5 m2/g, glass frit and an organic vehicle. According to another embodiment of the invention, the first copper particles are about 60-80 wt. % of the paste, while the content of the second copper particles is up to about 20 wt. % of the paste. According to another embodiment, the glass frit is lead-free and is about 1-10 wt. % of the paste. Preferably, the glass frit comprises a boron-zinc-barium oxide glass frit. According to another embodiment, the paste further comprises copper oxide. Another embodiment of the invention relates to an electroconductive paste comprising about 60-95 wt. % copper component, a boron-zinc-barium oxide glass frit, and an organic vehicle.

Light-emitting diodes (LEDs) are semiconductor light sources used in a variety of applications, including general lighting, street lighting, and automotive lighting, to name a few. LEDs emit light through an electroluminescence effect, whereby electrons and holes in a material, typically a semiconductor, recombine, causing the electrons to emit energy in the form of photons, or light. LEDs are advantageous over incandescent light sources because they consume less energy, have a longer lifetime, emit stronger light output, and are smaller in size.
One contributing factor in maintaining the long life of an LED is temperature regulation. High-power LEDs are subjected to higher junction temperatures, sometimes as high as 150° C., which cause stress on the material. Thus, LED performance is temperature-dependent. One way to structure an LED package in order to regulate its temperature is to use a thermal substrate. The majority of high power/high brightness (HP/HB) LED circuits manufactured today are based on Metal Core Printed Circuit Board (MCPCB) technology. The MCPCB system consists of a copper foil, which acts as the circuit layer, a polymer dielectric layer, and either an aluminum or copper base layer that acts as the thermal substrate. The aluminum or copper substrate has excellent thermal conductivity and provides for thermal dissipation away from the circuitry. The polymer dielectric layer electrically insulates the copper foil from the thermal substrate, while also having good thermal conductivity to allow the heat to be transferred to the thermal substrate.
The MCPCB system is typically manufactured using a subtractive process, whereby the copper foil, dielectric layer and thermal substrate are laminated together, and the copper foil is then chemically etched to create the desired electrical pattern to form the circuit layer. This process can be costly, as it is labor intensive and there is a significant amount of material waste through the copper etching process.
Therefore, an electroconductive component is needed that is simple to manufacture, has optimal heat dissipation properties, and reduces the amount of material waste resulting from the formation of the electrical leads. It preferably also results in the formation of dense fired leads that are highly conductive. The material used for the circuitry preferably is able to be processed at temperatures less than about 610° C., as aluminum substrates begin to distort at temperatures above 620° C. Further, the circuitry should adhere well to the dielectric layer. Lastly, the ideal LED system preferably performs well under a variety of environmental conditions, including automotive and outdoor uses.

Low firing temperature copper composition

Heraeus Precious Metals North America Conshohocken LLC


A method of preparing an ion-conducting material, for example membrane, having reduced sensitivity to water includes a step of treating an ion-conducting polymeric material (especially a sulphonated polyaryletherketone and/or sulphone) which has at least some crystallinity or which is crystallizable with a means to increase its crystallinity. The ion-conducting material prepared may be used in a Membrane Electrode Assembly of a fuel cell.

One type of polymer electrolyte membrane fuel cell (PEMFC), shown schematically in FIG. 1 of the accompanying diagrammatic drawings, may comprise a thin sheet 2 of a hydrogen-ion conducting Polymer Electrolyte Membrane (PEM) sandwiched on both sides by a layer 4 of platinum catalyst and an electrode 6. The layers 2, 4, 6 make up a Membrane Electrode Assembly (MEA) of less than 1 mm thickness.
In a PEMFC, hydrogen is introduced at the anode (fuel electrode) which results in the following electrochemical reaction:Pt-Anode (Fuel Electrode) 2H2→4H++4e−
The hydrogen ions migrate through the conducting PEM to the cathode. Simultaneously, an oxidant is introduced at the cathode (oxidant electrode) where the following electrochemical reaction takes place:Pt-Cathode (Oxidant Electrode) O2+4H++4e−→2H2O
Thus, electrons and protons are consumed to produce water and heat. Connecting the two electrodes through an external circuit causes an electrical current to flow in the circuit and withdraw electrical power from the cell.
Preferred ion-conducting polymeric materials for use as components of polymer electrolyte membranes in fuel cells have high conductivity (low EW, or high ion-exchange capacities), low water uptake, robustness and solubility in solvents which can be used to cast the membranes. However, some of the aforementioned requirements compete with one another. For example, steps taken to increase solubility of the materials in casting solvents may, disadvantageously, increase the water uptake of the materials; and steps taken to increase the conductivity of the materials will tend also to increase water absorption leading to premature failure of the materials when used in fuel cells.