A pump operations module having a base function includes only base function programming in the module itself but is configured to receive advanced delivery programs in a buffer for execution autonomously. An advanced interface module (AIM) is used to prepare advanced delivery programs and upload them to one or more delivery modules as well as monitor the performance of those modules. However, the advanced interface module does not control the execution of those advanced delivery programs by the pump operations modules. The AIM includes a touch screen and access to drug libraries. The AIM will generate graphical slide controls on the touch screen with the minimum and maximum values on the touch screen for the user to create an advanced delivery program for upload, to greatly lessen the risk of errors. Support for PK applications is provided.

The invention relates to control over medical delivery devices and more particularly, to medical delivery systems and methods having safety-enhancing configurations designed to lessen the effects of processor control errors.
Infusion pumps are in widespread use in the medical field. Numerous types of infusion pumps and infusion pump systems are known in the art. Infusion pumps have been designed with the base functions of a delivery rate and a volume-to-be-infused ("VTBI") (or delivery time and total dose). Over the years as processors have evolved with increased capability, faster speeds, and reduced cost, infusion pumps, as well as many other medical devices that deliver medical treatment to patients, have incorporated these processors and have become more complex with many more features made available. Very complex medication delivery profiles can be programmed into such pumps for the care and treatment of patients. Doctors, nurses, and technicians who are trained to program and use the complex features are often referred to as "super users." Such super users are able to program such pumps with very complex fluid delivery programs, and in some cases, configure them for specific use in particular wards of hospitals or other healthcare institutions.
Many of these advanced infusion pumps may be used in different pumping modes as the infusion pump may include several embedded programs to enable different operational modes. In the environment of intensive care units, cardiac care units, operating rooms, or trauma centers, it is often necessary to infuse into the patient one to eight different drugs simultaneously. In addition, some of the drugs used in these environments are not directly compatible with each other and therefore need to be infused into the patient at different points of the body. Such multiple infusions at different patient delivery sites require different pumping "channels" or pumping modules. In addition, it is frequently necessary to observe and recall the condition of the patient at certain intervals or to adjust the medication in accordance with the patient's reaction to it. To do so, changes to the pumping program of one channel may need to be made without disturbing drug delivery or device operation of other channels. In addition, in order to be able to recall patient conditions, large amounts of patient data must be stored and access to and manipulation of that data must be made available without disturbing any ongoing pumping processes.
In some cases, a modular programmable patient care system is used that comprises an apparatus for centrally interfacing with a plurality of connected functional devices that provide patient medication infusions and patient monitoring. The number of pumping modules, the complexity of the infusion programs that can be applied for each one, each program of which may differ from the others, and the number and complexity of patient monitors can generate a large amount of data for a central controller to process, and in some cases, can cause data programming and monitoring overloads. Even with single channel devices, the complexity of monitoring and controlling the device has created a time management issue when the user interface is added to the activities being controlled and responded to by the processor. Adding multiple channels just increases the probability of time management issues.
Such systems containing multiple infusion pumping devices are known in the medical field and are a natural response to the need for multiple pumps on a single patient. For example, U.S. Pat. No. 4,756,706 to Kerns et al. discloses a centrally-managed infusion pump system in which pump and monitoring modules are attached to a central management unit (CMU) or central controller. The central management unit controls the internal setup and programming of each of the attached pump modules, and receives and displays information from them.
U.S. Pat. No. 4,898,578 to Rubalcaba, Jr. also discloses a medication infusion system that includes a plurality of infusion pump modules that may selectively be attached to a central management unit or central controller (CMU) so as to provide for centralized control. In particular, the CMU obtains infusion parameters from the user and then performs calculations with the parameters to establish the desired infusion rate at a designated attached pump module. Once this rate is determined, the central management unit controls the infusion accordingly.
Turning now to FIG. 1, there is shown an existing medication delivery system 20 comprising a central management unit 22 (CMU), three infusion pumps 24, 26, and 28, and an oximeter 30, all of which are connected with and controlled by the CMU. All of the infusion pumps and the oximeter are connected with the same patient 32 in this example. All the foregoing devices 22, 24, 26, 28, and 30 are mounted to a floor stand 34 having a stable base 36. Also mounted to the floor stand at its top is a medication hanger 38 from which three medication containers are hung 40, 42, and 44. The right-most container 40 is connected with the top pump 24 and the patient 32 through a fluid line 46, with the pump controllably delivering the fluid of the container 40 to a first delivery site 47 at the patient. The middle container 42 is connected with the center pump 26 and the patient 32 at a different location, or delivery site 49, than the top pump through a fluid line 48, with the pump controllably delivering the fluid of the container to the patient. The left-most container is connected with the bottom pump 28 and the patient 32 through a fluid line 50 with the pump controllably delivering the fluid of the container to yet another delivery site 51 on the patient. The oximeter 30 receives oximetry data from a sensor (not shown), located at the patient at a location 53, selected so at to sense the necessary patient physiology, through a data line 52 for processing.
The CMU of FIG. 1 includes a user interface 58 comprising a display 60 and a keypad 62. The CMU receives programming input through its interface 58 and provides real-time programming control over each of the pumps or channels 24, 26, and 28. The CMU provides instructions to each of the pumps in real time to which they are responsive, it monitors the functional operation of each pump, and it monitors the operating timers of each pump and its respective processor. The CMU stores a drug library that is used both as a safety feature and a data base. The CMU monitors the delivery of each pump and updates instructions in real time to each pump according to programming of the CMU and possibly in accordance with oximeter data. The CMU also responds to user data entry to update instructions to one or more of the pumps. The pumps are responsive in real time to the updated instructions; i.e., they are under the direct control of the CMU. The CMU may or may not be connected with a remote processor, such as a pharmacy server, or an administration server central to a healthcare facility.
In the centralized control systems discussed above, there are several disadvantages. For example, in these systems the central management unit must be aware of and must control much of the functionality of the attached pump units. This can result in a large data processing load for the CMU. Some systems include a single complex central management unit (CMU) that must be used to control and program multiple infusion pumps. Complex central management units having a high data processing load are undesirable in clinical situations due to the possibility that a data overload may occur in which the processor is unable to timely process all data and output instructions. In such a situation, the CMU typically shuts down and consequently, all pump modules are shut down since they are under the direct control of the CMU. Shutdowns of the CMU and its pump modules can occur unpredictably with the result that the patient does not receive the medication at the desired time unless the system can be reset and restarted immediately or a replacement system can be located and programmed immediately. The same shutdown can happen in a single-channel pump where the processor becomes overwhelmed by complex programming and data processing requests.
Medication errors, that is errors that occur in the ordering, dispensing, and administration of medications, regardless of whether those errors cause injury or not, are a significant consideration in the delivery of healthcare in the institutional setting. The Sep. 9, 2002 issue of Archives of Internal Medicine reported a study indicating that nearly one in every five doses of medicine given to patients in the typical hospital is a medication error ("Medication Errors Observed in Thirty-Six Health Care Facilities"). This study confirms the findings from earlier reports, including the 1999 Institute of Medicine Report, which revealed that more than 50,000 deaths in the United States annually are the result of medication errors. Medication errors are the eighth leading cause of death in the United States. Additionally, adverse drug events ("ADE") defined as injuries involving a drug that require medical intervention, which are a subset of medication errors, represent some of the most serious medication errors, and are responsible for a number of patient injuries and death.
Healthcare facilities continually search for ways to reduce the occurrence and severity of medication errors. Various systems and methods have been considered and developed at present to reduce the frequency of occurrence and severity of preventable adverse drug events ("PADE") and other medication errors.
Manufacturers have tried using various techniques to avoid infusion errors, one of which includes the use of hand-held personal digital assistants ("PDA") that are designed to provide drug administration scheduling, drug administration verification, and the electronic documentation of drug administration. These devices are predominantly used to verify the administration of oral, intramuscular ("IM"), subcutaneous, and topical drugs and have limited capability in verifying the administration of intravenous ("IV") drugs. PDAs have been found to be useful for scheduling and perhaps monitoring, but can do very little or nothing about data overload and shutdown of an infusion pump system.
Healthcare facilities continuously strive to provide quality patient care and many steps have been taken to lessen the chances of such errors occurring. The possibility of medical errors, such as where the wrong patient receives the wrong drug at the wrong time, in the wrong dosage, or even where the wrong surgery is performed, are a significant concern for all healthcare facilities. Various solutions to these problems have been proposed, such as systems that use bar codes or RFID tags to identify patients and medications, or systems allowing the beside entry of patient data. While these systems also have advanced the art significantly, infusion data processing and programming errors continue to be a problem. For example, even where the medication order includes the correct infusion parameters and those parameters are correctly entered into an infusion pump, a data overload of the pump's processor or a remote centralized processor may cause the pump to stop administering the medication to the patient, thus causing a delivery error to the patient.
As briefly mentioned above, very complex pumping programs can be generated in the care and treatment of patients. The ability to control automatically a pump to provide a complex medical delivery regimen or pattern can have a significant benefit for a patient. A medication delivery pattern can be designed to optimize delivery of a particular medication that takes into account factors of the particular situation. Costs are lowered since the attention of nurses is not required each time a delivery parameter of the pump must be changed—it is done automatically. Although conventional drug infusion controllers have greatly improved the efficiency and ease with which medications are delivered to a patient, complex pumping programs, and the data produced from them, can reach the limits of certain processors. Data overloads are possible and their occurrence is not predictable. In some areas of medication delivery, even higher levels of data and instruction processing are necessary. The processor is "highly" taxed and when multiple requests are made of the device, changing delivery parameters occur, complex algorithms are running, single fault failure timing is in place, etc., devices on the market are shutting down without alarm conditions in some instances. The issue is the defined frequency of monitoring and control interface with the pump while also needing to recognize and respond to the user interface.
For example, certain pharmacokinetic models can require very complex infusion programs. U.S. Pat. No. 5,010,473 to Jacobs discloses a model-based open-loop process for controlling the concentration of a drug delivered intravenously to a patient as a function of the rate of infusion. A three-compartment pharmacokinetic (PK) model is used to determine the plasma drug concentration. Such PK systems are attractive for certain therapy, but require a large amount of programming, data manipulation, and control. Based upon the linear relationship between data pairs comprising a rate of infusion and a corresponding plasma drug concentration, an interpolated rate is determined by a microprocessor as a function of the specified plasma drug concentration. The actual infusion rate of the drug during successive time intervals is repetitively used to compute the plasma drug concentration at the end of each time interval. For each iteration, state variables from the previous computation are applied to determine the next interpolated infusion rate. Open-loop medication delivery control methods can achieve the specified plasma drug concentration, but a relatively complex medication delivery program is incorporated.
It will be apparent that controlling the administration of a plurality of drugs through a multi-channel drug infusion system using a PK model to predict the drug concentration and control the rate of infusion would require significant programming tasks over the prior art control of a single channel. If desired, a different PK model could then be selectively applied to control the delivery of each different drug through each channel of a multi-channel drug delivery system, or the same model could be used for the control of each channel of the system.
At times, a physician may find it necessary to alter briefly the parameters of a drug therapy. If the drug administration is being controlled by a PK model, the physician may want to switch to a manual mode for a period of time, for example, to administer a bolus dose. It should thereafter be possible to switch back to the PK model controlled mode. Accordingly, it is important that the control for a pump that is used to administer drugs in accordance with a PK model be able to track the history of the drug administered and take into consideration changes that occur while the PK model controlled mode is interrupted by a manual controlled mode, when the PK model control mode resumes. Since the history of the blood plasma concentration must be retained to achieve this goal, the infusion system control should be able to display both historical and predicted blood plasma and compartment effect drug concentrations levels to medical personnel for each drug administered, during either model controlled or manual controlled modes of operation. The model should continue to track and display these parameters, even after the drug infusion has stopped, so long as the patient's case is active. If all the above is performed by an infusion pump, or by a system of pumps with a central controller, significant data processing loads can occur for the processor or processors involved. Should such data loads exceed the processor's capability, a shut-down may occur and the therapy could be delayed.
It has been recognized that infusion pump designs currently on the market present potential safety issues. This may best be demonstrated by the fact that the U.S. Food and Drug Administration ("FDA") issued a proposed Infusion Pump Improvement Initiative on Apr. 22, 2010. Their justification for the initiative is that the number of recalls and potentially understated number of safety events involving infusion pumps are too high.
Observations:
The following observations are made after a review of FDA Medical Device Reports ("MDRs"), details provided with infusion pump recalls, and assessment of human factors known to exist in health care facilities.
During pump operation, software, hardware, and the user interface make major contributions to reported causes of pump recalls.                A. The intravenous (IV) infusion pump hardware/software interface uses a master/slave model where the master process controller, or "master processor," is the master for multiple channels. The master/slave relationship mandates that the pump channel operate only when the master control module or processor is functioning properly. This master/slave model can result in conflicts between the master processor's need to perform specific system checks and the user's demand for the master processor to process instructions being provided by the user. The processor as the master requires that the pump performance be interrupted if a processor or control module failure occurs.        B. To clarify the above problem through a comparison to another high data load system, video game programmers are faced with the same problem in that as the console game program begins to utilize too high a percentage of the processor's capacity, the "super user" begins to see slight delays in the video updates (for example, characters begin to freeze in place on the screen). The same is true with IV infusion pumps. The exception is that with the IV pump, the super user sees an error code or a potential programming error. The significant number of recalls associated with this design approach has been used as part of the FDA Infusion Pump Improvement Initiative
Complexities of pump programming are not supported with the user interface screens provided with the feature-enhanced infusion pumps currently on the market.
Numerical keypads have a similar data entry error rate regardless of the style of keypad used. This added with the human factor of confirmation bias (humans tend to fail to check closely when asked to confirm) results in some level of over- or under-infusion of the solution (drug).
The advanced infusion pumps provide the users with the ability to program the pumps to address many different therapeutic procedures. However, the same feature enhancements require the user to program the pump while advancing through a series of screens. Each screen may use the same key as previously used for a different purpose. The potential errors associated with multiple functions for the same key potentially increase the error rates experienced as practitioners move from one patient population to another.
Infusion pumps are designed to address all of the needs in the healthcare facility; i.e., they have the ability to pump a wide range of volumes. This increases the pump's ability to deliver significantly more fluids than reasonably logical to neonatal patients and also allows deliveries so small that the delivery rates are not clinically significant for large adult patients.
The infusion pumps do not support easy readability during operation. This is especially true when multiple channels are operating and an error condition is detected. Alarms sound and delivery stops or is affected as a result of the error conditions. This condition is further complicated when the practitioner attempts to clear the error condition at the CMU and incorrectly takes action on channels not affected by the error condition.
No infusion pump currently on the market known to the inventors was designed to address the specific needs of anesthesia.
No infusion pump currently on the market addresses the specific needs of the neonatal intensive care patient population. Specifically, the drug dilution of many drugs being delivered at the same time may actually require the neonatal patient to receive more total fluids than is therapeutically beneficial to the patient.
Hence those skilled in the art have recognized a need for safer medication delivery devices. A need has also been recognized for a medical delivery device that is not susceptible to terminating delivery of a medication in the event that a remote processor that is controlling delivery ceases functioning properly. An additional need has been recognized for a medical device that is capable of receiving and operating under a complex medication delivery program. Another need has been recognized for safer data input devices and methods so that fewer mistakes are made when inputting data related to medication delivery. The invention fulfills these needs and others.

Distributed medication delivery system and method having autonomous delivery devices


A high efficiency ultrasonic surgical aspiration tip apparatus and accompanying method for surgical use. The apparatus has one or more substantially xe2x80x9cVxe2x80x9d or xe2x80x9cUxe2x80x9d shaped cuts in a contacting. The apparatus and method of use provides a cutting action at the contacting end when the tip is ultrasonically excited. The apparatus and method of use further provides a substantially uniform ultrasonic and aspiration field due to the positioning and shape of the substantially xe2x80x9cVxe2x80x9d or xe2x80x9cUxe2x80x9d shaped cuts. The aforesaid further allows a surgeon to position the ultrasonic generator handpiece at any rotational angle for provision of the benefits cited.

The art of the present invention relates to ultrasonic surgical devices in general and more particularly to a high efficiency ultrasonic tip for use in neurosurgery and other surgical disciplines. The use of ultrasonic aspirators in neurosurgery is well understood and recognized in the field of neurosurgery. Ultrasonic aspiration provides for emulsification and in situ evacuation of intracranial tumors. In this way, retraction of eloquent brain is minimized, while disruption and removal of tissue is advanced.
Prior art ultrasonic aspirators typically utilize a tubular tip having a threaded connecting end and a contacting end. The threaded connecting end attaches to an ultrasonic generator handpiece which injects ultrasonic energy into the tip and further allows for aspiration through said tubular tip. Said energy causes said tubular tip to elastically elongate and retract along the tubular axis at a frequency corresponding to the ultrasonic excitation frequency of the ultrasonic generator. Often the contacting end of said prior art devices is best described as a planar cut perpendicular to the tubular axis of the tubular tip. In other words, the contacting end is simply a flat cut at the tube end which is again perpendicular with the lengthwise tubular axis of the tip.
Prior art ultrasonic aspirators for neurosurgery rely solely upon the phenomenon of cavitation to reduce tissue to its emulsified form. That is, the contacting end of said prior art extends and retracts up to 350 microns at a rate from 20 to 50 kilohertz, thereby producing an ultrasonic field which creates a low pressure cavitation zone at the contacting end. The resulting low-pressure zone at the tip of the aspirator causes cell wall collapse and release of intracellular fluid which creates an emulsate. Therafter, said emulsate is aspirated through said tubular tip via the action of an aspiration system connected inline with said ultrasonic generator handpiece and said tubular tip.
This prior art method of emulsification and aspiration is extremely safe, as it maintains some selectivity of destruction and limits disruption of tissues with low water mass. However, there are times when this selectivity becomes problematic. Fibrotic meningiomas and calcified tumors are minimally affected by the aforementioned cavitation phenomenon thereby dramatically increasing operative time or in some instances completely prohibiting the use of ultrasonic aspiration for their removal. Hence, the benefits of in situ evacuation are lost on these pathologies. Likewise, tumors previously treated with radiosurgery can often find themselves xe2x80x9cweldedxe2x80x9d to surrounding pathology. (i.e. dura, bony prominences within the skull base, etc.) Again, the aforementioned limitations of ultrasonic aspiration apply.
The present art utilizes an ultrasonic field to produce the aforementioned cavitation along with a cutting action at the contacting end of the uniquely designed tubular tip. That is, the present art provides in situ evacuation of the aforementioned intracranial tumors. The aforesaid cutting is promoted at the ultrasonically excited contacting end when the contacting end is not perpendicular to the tubular axis of the tubular tip. In other words, since the ultrasonically excited contacting tip longitudinally extends up to 350 microns, a slicing or mechanical cutting action may be promoted when the contacting tip has an angle relative to the tubular axis. Unfortunately, a simple angle on the contacting end relative to the tubular axis does not promote efficient aspiration or an optimum ultrasonic field.
The present invention represents a tubular tip having a xe2x80x9cVxe2x80x9d or xe2x80x9cUxe2x80x9d shaped cut or notch within the contacting end which provides optimum slicing or cutting action while also maintaining asymmetrical handpiece operation, an optimum ultrasonic cavitation field, and optimum aspiration. That is, the present invention represents a tubular tip which is utilized in the aforementioned prior art ultrasonic generator handpiece and provides the traditional ultrasonic and aspiration benefits and allows a surgeon to use the ultrasonic handpiece in any rotational axis position. The tubular tip has a connecting end and a contacting end, yet the contacting end is uniquely shaped to provide the aforementioned cutting action. In a preferred embodiment, said contacting end contains a substantially xe2x80x9cVxe2x80x9d or xe2x80x9cUxe2x80x9d shaped cut which provides the desired cutting or slicing action along with a desirable locus for uniform aspiration and ultrasonic field generation. The base of the aforementioned xe2x80x9cVxe2x80x9d or xe2x80x9cUxe2x80x9d cut is placed opposite the contacting end, or towards to the connecting end.
Accordingly, it is an object of the present invention to provide a high efficiency ultrasonic surgical aspiration tip having a contacting end which promotes mechanical cutting and slicing of various tissues and other materials, including fibrotic meningiomas and calcified tumors.
Another object of the present invention is to provide a high efficiency ultrasonic surgical aspiration tip having a threaded end which functions with prior art ultrasonic generator handpieces, produces a substantially uniform optimum ultrasonic and aspiration field, and also provides the desired cavitation.
A further object of the present invention is to provide a high efficiency ultrasonic surgical aspiration tip which provides an asymmetrical ultrasonic generator handpiece operation while also promoting efficient and convenient aspiration.
To accomplish the foregoing and other objects of this invention there is provided a high efficiency ultrasonic surgical aspiration tip and method of using the same. The method and apparatus provide for a unique and desired cutting or slicing action while further providing the traditionally desired aspiration and ultrasonic field generation. In a preferred embodiment, the apparatus is claimed in conjunction with a conventional ultrasonic generator handpiece of a surgical aspirator and the method of use is claimed in conjunction with the action of surgical tissue and tumor removal.
As aforementioned, in its preferred embodiment, the present art represents a tubular tip having a connecting end, a contacting end, and a xe2x80x9cVxe2x80x9d or xe2x80x9cUxe2x80x9d shaped cut or notch within the contacting end which provides optimum slicing or cutting action while also maintaining asymmetrical handpiece operation, an optimum ultrasonic cavitation field, and optimum aspiration through the interior tube portion of the tip. In the preferred embodiment, the base of said xe2x80x9cVxe2x80x9d or xe2x80x9cUxe2x80x9d shape is positioned closer to the connecting end than the legs of the xe2x80x9cUxe2x80x9d or xe2x80x9cVxe2x80x9d. That is, the tips of the legs of the xe2x80x9cUxe2x80x9d or xe2x80x9cVxe2x80x9d represent the tip of the contacting end and face away from the connecting end. In the preferred embodiment, the connecting end comprises a male threaded portion which mates with a female threaded portion on the ultrasonic generator handpiece. Said connecting end further comprises a shoulder, away from said connecting end and toward said contacting end, which seats upon and with the mating end of the acoustic horn of the ultrasonic generator handpiece of the aspirator. Alternative embodiments may utilize attachment methods at the connecting end other than threads. These include but are not limited to mating pinned portions, welding, sweated connections, soldered connections, brazed connections, mechanical quick disconnects, and ball and detent connections.
Alternative embodiments utilize variations of the xe2x80x9cVxe2x80x9d or xe2x80x9cUxe2x80x9d cut in the contacting end. That is, a first alternative embodiment contains multiple xe2x80x9cVxe2x80x9d or xe2x80x9cUxe2x80x9d cuts at the contacting end which form in combination a serrated cut at the contacting end. Further alternative embodiments embody an asymmetrical xe2x80x9cVxe2x80x9d or xe2x80x9cUxe2x80x9d shaped cut at the contacting end. That is, one leg of the xe2x80x9cVxe2x80x9d or xe2x80x9cUxe2x80x9d is shorter or longer than the other. Still further alternative embodiments provide honed or sharpened edges on said contacting end to further the aforementioned cutting action.
In all of the aforementioned preferred and alternative embodiments of the present art a uniform and symmetric ultrasonic field is generated substantially near the contacting end and in line with the tubular axis of the tip. This desirable feature is not present in prior art devices which provide for or offer cutting action. That is, prior art devices have provided only a single or single compound angular cut on the contacting tip which does not provide a uniform and symmetric ultrasonic field at the contacting tip. That is, the prior art cut on the contacting end is asymmetrical, thereby limiting the ultrasonic energy which is transmitted to the fluid, tissue, or tumor in which it is embedded and further creating an asymmetric ultrasonic field in said medium. An asymmetric field forces the user to rotate the ultrasonic generator handpiece to place the ultrasonic field or cavitation at the desired location since the ultrasonic field does not radiate in a uniform or half-sphere isotropic manner from contacting end.
The preferred and alternative embodiments of the present art also provide the desirable optimum aspiration at the contacting end. Since the ultrasonic handpiece is substantially tubular in nature, a surgeon typically desires to utilize the ultrasonic handpiece without concern as to rotational position about the tubular axis. This is not possible with prior art tips which provide for a cutting action. Since the present art contacting end maintains a substantially planar front at the contacting end, aspiration and field generation occurs primarily inline with the tubular axis. This again, allows the user to asymmetrically position the ultrasonic generator handpiece while maintaining effective aspiration and ultrasonic cavitation effects. In toto, the present art maintains all of the prior art benefits of optimum placement and generation of the ultrasonic field and optimum asymmetrical aspiration while providing enhanced mechanical cutting action.
The present art tubular tips may be manufactured from a variety of materials which provide the desired modulus of elasticity and a sufficiently high elastic limit to withstand the transmitted ultrasonic energy. Materials include but are not limited to metals and their alloys of steel, stainless steel, titanium, and super-elastic nickel titanium. Further manufacturing materials include ceramics, composites, and plastics. The method of manufacturing the present art with the xe2x80x9cVxe2x80x9d or xe2x80x9cUxe2x80x9d cuts include but are not limited to traditional machining methods or non-mechanical machining methods such as laser cutting and electrical discharge machining (EDM).
The art of the present invention as contemplated is effective in the in situ evacuation of intracranial tumors. However, it is also capable of in situ evacuation of intervertebral disc material, thereby facilitating a minimally traumatic discectomy, and further use in ophthalmic ultrasonic surgery. It is also specifically contemplated that the present device could be used in general endoscopic surgery, including but not be limited to, surgery of the colorectal tract, biliary system, thoracic cavity, and other pathologies not mentioned. A variant of this device could further be utilized for intravitreal fragmentation of dislocated crystalline lenses.
In use, the surgeon or assistant, first installs the tip within the mating end of the acoustic horn of the ultrasonic generator handpiece. In the preferred embodiment, this is by screwing the tip into the mating end and applying the proper torque. Once installed, the surgeon may, if desired or necessary for the surgery, place an irrigation sleeve or flue around said tip aft of said contacting end before the operation begins. (The irrigation sleeve allows the handpiece to provide irrigation fluid to the surgical site through the ultrasonic handpiece.) During the surgical procedure, the surgeon places the contacting end onto or near the tissue or tumor which he or she desires to remove. Once placed, the surgeon then energizes the ultrasonic generator handpiece and the vacuum aspiration system if desired. The ultrasonic energy transmitted to the contacting end then creates a uniform ultrasonic field relative to the tubular axis of the tip. This field is of such high frequency and amplitude that the liquid or tissue surrounding it cavitates or breaks down. This allows for removal of said material through the interior tube portion of said tip via the aforesaid vacuum aspiration.

High efficiency ultrasonic surgical aspiration tip


Described is a system for providing quick and efficient identification of a desired version of content from an editing history of the content. The system receives a search index identifying versions of content from an editing history of the content. The system sorts the search index according to sort criteria and receives a selection from the sorted search index of a first version of the content and a second version of the content. The system identifies and displays one or more content differences between the first and second versions of the content.

Conventional systems provide for determining difference between documents. Conventional word processing and document editing applications typically have features that allow a user to view content differences between documents and locations within the documents at which the content difference occur. Such conventional applications require the user to identify the documents the user wishes to be compared and to provide folder paths for each file in order for the conventional applications to access the respective documents for comparison.

Extensible version history and comparison within a backup


The self-watering planter has two mantles insertable into each other, forming an annular space therebetween to define a soil space inside an inner mantle and a water space in communication with the soil space for bringing the water from the water space into the soil space. A channel is formed in the annular space defined by the mantles and connected to the water space. An opening is provided in the wall of an outer mantle for supplying the water through the channel to the water space. An arm member is movable longitudinally in the channel along a guide formed in at least one of the mantles and a float member is connected to the arm member for adjusting its position depending on the amount of water in the water space. A flap is formed in the upper part of the arm member for closing the opening upon the water space being fully filled. The float member is eccentrically fixed to the arm member such that the buoyancy acting on the float member acts also on the arm member and the flap revolving them towards the outer mantle wall.

This invention relates to a self-watering planter of the type which comprises a soil space and a water space, intercommunicating in order to bring the water placed in the water space into the soil space preferably by absorption. The self-watering planter comprises in addition a channel or similar communicating with the water space, in which the opening or similar opposite to the water space is intended to provide for the water supply. The channel comprises an arm member disposed to be movable in the longitudinal direction of the channel, the position of which is adjusted by the intermediation of a float element or similar connected to the arm member as a function of the amount of water present in the water space.
Self-watering planters of this type are known and usually the channel for water filling is disposed in a vertical position to penetrate the soil space. Although such a construction is functional per se, it has a number of drawbacks, which has resulted in the present invention. In fact, 80% of faded pot-plants have been found to be due to excessive watering.


A device for filtering particulates from an exhaust gas feedstream of an internal combustion engine includes a filter substrate having a multiplicity of alternately closed parallel flow passages having porous walls oriented parallel to a flow axis of the exhaust gas between an inlet and an outlet thereof, wherein subsets of the flow passages are associated with respective ones of a plurality of zones, a flow control valve to control flow of exhaust gas to each of the plurality of zones, a multi-zone heating element including a plurality of individually activated heating elements each corresponding to one of the plurality of zones.

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
An aftertreatment system for managing and treating an exhaust gas feedstream can include a particulate filter device that removes particulate matter, e.g., elemental carbon particles from the feedstream. Known applications for a particulate filter device include internal combustion engines operating lean of stoichiometry, including, e.g., compression-ignition (diesel) engines and lean-burn spark-ignition engines. Known particulate filter devices require periodic regeneration to oxidize and remove the filtered particulate matter from the particulate filter device. Regeneration can require operations that increase temperature of the particulate filter device. Increasing temperature of the particulate filter device can include increasing temperature of the exhaust gas feedstream, including, e.g., operating the internal combustion engine at a rich air/fuel ratio under high speed/high load operating conditions, and injecting hydrocarbons into the exhaust gas feedstream upstream of an oxidation catalyst that is upstream of the particulate filter device, among other operations. Such operations can have associated fuel penalties. It is also known that high temperature operation of particulate filter devices can reduce service life thereof.


An apparatus and method for measuring viscosity or related properties of fluid samples in parallel is disclosed. The apparatus includes a plurality of tubes and reservoirs in fluid communication with the tubes. The tubes provide flow paths for the fluid samples, which are initially contained within the reservoirs. The apparatus also includes a mechanism for filling the reservoirs with the fluid samples, and a device for determining volumetric flow rates of fluid samples flowing from the reservoirs through the plurality of tubes simultaneously. The disclosed apparatus is capable of measuring viscosity or related properties of at least five fluid samples simultaneously. Useful reservoirs and tubes include syringes.

The present invention provides an apparatus for measuring viscosity or related properties of fluid samples in parallel. In some embodiments, the apparatus includes a plurality of tubes and reservoirs in fluid communication with the tubes. Each of the tubes has a predetermined length and a uniform inner diameter over at least a portion of the tube""s length. In addition, the tubes provide flow paths for the fluid samples, which are initially contained within the reservoirs. The apparatus also includes a mechanism for filling the reservoirs with the fluid samples, and a device for determining volumetric flow rates of fluid samples flowing from the reservoirs through the plurality of tubes simultaneously. The disclosed apparatus is capable of measuring viscosity or related properties of at least five fluid samples simultaneously.
The present invention also provides an apparatus comprised of an array of syringes for measuring viscosity or related properties of fluid samples in parallel. Each of the syringes includes a barrel for containing the fluid samples, a plunger located within the barrel for aspirating the fluid samples into the barrel, and a hypodermic needle in fluid communication with the barrel. The hypodermic needle, which has a substantially uniform diameter over a majority of its length, provides a flow path for the fluid samples. The apparatus also includes upstream and downstream detector arrays that are located along the barrel of each syringe. The detector arrays, which monitor volumetric flow rates of the fluid samples through each hypodermic needle, are capable of measuring viscosity or related properties of at least five fluid samples simultaneously.
Additionally, the present invention includes a method of screening fluid samples. The method comprises (1) providing fluid samples to a plurality of reservoirs; (2) allowing the fluid samples to flow from the reservoirs through a plurality of tubes; and (3) detecting the volumetric flow rates of at least five of the fluid samples through each of the tubes simultaneously.
Another embodiment of the present invention uses the same viscometer design with upstream and downstream detectors described above, but places at least one of those viscometers on tip of the arm of a three axis robot, and preferably at least two viscometers are placed on the tip of at least two arms of a three axis robot. In this embodiment, the viscometer is operated in the same manner described above and is moved from well to well of a sample tray or combinatorial library of samples. Many known liquid handling systems incorporate one or more tips and the viscometer may be placed on as many tips as are present in the robot being used. In addition, when multiple arm robots with multiple tips are used a high throughput instrument for viscosity measurements is provided. For example 8 tips on a 9 mm pitch may be provided on one or more arms of the robot. Thus, this embodiment of the present invention is either a rapid serial measurement or a simultaneous measurement on multiple samples.

Method of using a high throughput viscometer


A scanning system having a motor-driven scanning element automatically shuts down a scanning laser when the motor is either inoperative or operating below a safe speed. A microprocessor already used to drive the scanning circuitry is also used to control the operation of the motor, including commutation logic, and also controls the automatic laser shut-down. This results in a significant reduction of power requirement.

The present invention generally relates to scanning systems capable of reading bar codes. More particularly, the present invention provides a safety feature for disabling a scanning illuminator when the movement of the scanning mirror is inadequate (too slow or absent).
Some scanning systems of the laser (light amplification by stimulated emission of radiation) type focus a laser beam upon a motor-driven, rotating or dithering scanning mirror such that the laser beam forms a scanning pattern across a target bar code. The scanning laser beam is back-reflected to a photodetector, which determines the intensity of the back-reflected laser beam and outputs a current in proportion thereto. Thus a varying signal is output by the photodetector as the laser beam sweeps across a pattern of light and dark "bars" in a bar code.
Control circuitry controls the cooperation and coordination of the components (including the timing) and converts the photodetector output signal into useful form. Scanning speed is chiefly controlled by the speed of the motor.
The preferred embodiment of the present invention has a three-phase, direct current (DC) motor of the brushless type. Rather than using a commutator (for appropriately reversing the magnetic fields to "pull" the armature around its axis), varying signals (commutation logic) are applied to the appropriate windings to cause the magnetic fields to constantly change. The commutation logic is microprocessor controlled.
A three-phase motor is used instead of a single-phase motor since it provides for constant instantaneous power, and therefore a constant speed--an important feature for scanning operations.
An important safety consideration is to be able to shut down the laser if the the motor and thus scanning mirror cease operating, or operate below a certain speed. The result of motor malfunctioning is unnecessarily prolonged laser beam projection on the scanning surface, upon pattern mirrors in the scanner, and out of the scanner into free space.

Scanning system having automatic laser shutdown upon detection of defective scanning element motion


A dishwasher door assembly includes a frame, an inner door panel and a decorative outer door panel. The door is assembled by snap-fitting the inner door panel to the frame and then further snap-fitting the decorative outer panel over the frame. Thereafter, mechanical fasteners are inserted in aligned openings formed in the outer door panel, frame and inner door panel. This overall arrangement enables a consumer to select between various decorative outer door panels available to a retailer such that an outer door panel of a desired color and/or style can be sold with the overall dishwasher. The overall door assembly is preferably formed from plastic so as to be lightweight, yet structurally sound.

1. Field of the Invention
The present invention pertains to the art of appliances and, more particularly, to a molded plastic door assembly for a dishwasher.
2. Discussion of the Prior Art
When purchasing a dishwasher, a consumer would typically have to select a particular model, followed by a particular style. For instance, it is common to provide three or more styles for any particular dishwasher model, with the styles generally only differing by the color of the outer surface of a door of the dishwasher. Commonly, dishwasher doors are available in white, almond and black colors. Given that the doors between these various style dishwasher door assemblies only differ in visible appearance, it has been heretofore proposed to construct a dishwasher door with interchangeable front door panels of varying colors. Therefore, it is known to provide dishwashers with interchangeable front panels which advantageously allows a consumer to simply select between various decorative outer door panels when purchasing a particular dishwasher model.
Interchangeable dishwasher panels as proposed in the prior art are typically rectangular in shape and designed to only cover the front side of the dishwasher door. Such door assemblies typically utilize grooves or bracing members along a frame of the dishwasher door for receiving the decorative panel. Often the decorative panels are held in place with retainer strips positioned along an edge of the door frame. This overall arrangement requires the assembly of a fair number of components which must be maintained in respective positions in order to accommodate the retainer strips. The use of these multiple assembly components and the requirement for maintaining a certain alignment during the overall assembly is considered to lead to disadvantageous assembly costs.
In today""s marketplace, dishwasher door assemblies, with or without decorative front panels, almost invariably have metal frames. The use of metal in forming door frames is considered to disadvantageously add weight to the overall structure. Most typical assemblies utilize metal screws and the like which require alignment between holes formed in the various components and, inherently, longer assembly times. In any event, for at least these reasons, there exists a need in the art for a dishwasher door assembly that is preferably formed of plastic so as to be lightweight, while being structurally sound. More particularly, there exists a need in the art for a dishwasher door assembly which is simple in construction, incorporates at least a frame and a decorative front panel which can be easily interconnected to the frame in a time efficient and effective manner, with the front panel being of a selected color and/or style.
The present invention is directed to a dishwasher door assembly including a door frame, an inner door panel and a decorative outer door panel. In accordance with the most preferred embodiment of the invention, the door frame is sandwiched between the inner and outer door panels, with each of the inner and outer door panels being snap-fittingly connected to the door frame. The decorative door panel preferably fits over at least side portions of the door frame. The door frame actually defines a housing for a control panel, as well as constituting a support for the overall door assembly. In accordance with the invention, each of the door frame, inner door panel and decorative outer door panel are formed of plastic.
In the most preferred form of the invention, side portions of the door frame are formed with slots for receiving tabs provided on each of the outer door panel and inner door panel. That is, the inner door panel includes tabs that extend outward from a body portion thereof. As the inner door panel is joined to the door frame, the tabs register with structure provided on the door frame such that a snap-fit connection is affected. In a similar manner, the decorative outer panel is formed with tabs which are snap-fitted to the door frame. More particularly, the outer door panel is formed with various projections which are slidably received within slots provided in the door frame, whereupon the outer door panel is pivoted and snap-fittingly attached to the door frame about side portions thereof. As the outer door panel and the door frame are joined, the outer door panel covers at least front and side portions of the door frame to establish an overall aesthetic arrangement. Additional mechanical fasteners can be utilized to finalize the overall assembly.
With this construction, the dishwasher door assembly of the present invention presents a lightweight and structurally sound door assembly that can be easily assembled with substantially self-aligning parts being connected in a snap-fit manner. In accordance with the invention, an overall dishwasher model can be selected by a consumer, followed by a particular decorative outer door panel having a desired color and/or style, with the outer door panel being easily attached to the remainder of the door assembly to establish the final product.
Additional objects, features and advantages of the present invention will become more readily apparent from the following detailed description of a preferred embodiment thereof when taken in conjunction with the drawing wherein like reference numerals refer to corresponding parts in the several views.


An automatic paper ejecting and stacking machine for use with vertically-loaded desktop hole-punching equipment is disclosed. The ejector and stacker work together to remove vertically-fed paper stacks from a hole punch and align said stacks in a horizontal stacking bin adjacent the punch machine and preferably facing the operator. After the sheets are punched, a sheet transfer mechanism moves the vertically-oriented media stack in a horizontal direction from the punch machine/ejection assembly to the reception assembly. The sheet transfer mechanism may comprise a plurality of transfer paddles arranged on an drive belt wherein a motor rotates the belt to draw a paddle through the paper-receiving channel of the ejection assembly to push the media stack out of the channel. In one version, the media stack is flipped forward to rest in a forward-facing tray, while in another embodiment, the media stack is pushed rearward to rest in a rear-facing tray.

1. Field of the Invention
This invention relates generally to the field of desktop document handling equipment. More specifically, this invention relates to an automatic paper ejector and stacking device for use with vertically-loaded desktop hole-punching equipment.
2. Related Art
The commercial printing industry, large offices and other business entities often require the use of desktop paper-handling equipment. The benefits of automating paper-handling tasks such as punching, sorting and binding are well known. Automation not only simplifies these paper-handling processes but also improves efficiency and lowers costs via reduction or elimination of operator requirements. Consequently, numerous automatic paper-handling devices have been developed.
Paper stacking machines are known in the printing industry. U.S. Pat. No. 6,443,450 (Antinora) teaches a sheet stacking apparatus wherein a rotating disk receives sheets of printed media. After the disk receives at least two sheets of printed media, a controller rotates the disk to or past a sheet stacking position and the printed materials are stacked accordingly. U.S. Pat. No. 4,275,874 (DiBlasio) discloses a stacker for handling and counting documents wherein a slotted stacker wheel assembly at the bottom of a media transfer path receives documents from the media transfer path and delivers the documents to a stacker tray substantially beneath the input tray.
Renz America Corporation (Agawam, Mass.) has produced an electric high output tabletop punch machine for professional and office use. The punching machine includes mechanisms for punching, ejecting and stacking paper of various sizes. Paper is manually fed into a vertical punching assembly by an operator. After holes are punched, an ejector mechanism clears the sheets of paper from the punching assembly by displacing the vertically-oriented sheets horizontally from the punching area to a position above the stacking area. Paper ejected from the punching area is then momentarily suspended above the stacking area in a shallow groove upon a shaft. The weight of the paper causes the punched sheets to fall into a stacking bin at the rear of the machine (opposite the operator).
Still, there is a need for an automatic paper ejecting and stacking machine for office and professional use that may be adapted for use with commercially available punching equipment to increase operational efficiency and productivity.

Automatic paper ejector and stacker for punch machine


An inkjet head having an electrostatic actuator and a manufacturing method of the same are disclosed. The inkjet head having an electrostatic actuator, comprising a stator, on which is formed a plurality of comb pattern shaped first protrusion parts and second protrusion parts in both directions, and a rotor consisting of a first component and a second component, the ends of which join with the diaphragm, wherein a third protrusion part is formed on the first component, facing the first protrusion parts and meshing with the first protrusion parts without contact; and a fourth protrusion part is formed on the second component, facing the second protrusion parts and meshing with the second protrusion parts without contact, may decrease the size of the head composition and may increase the electrostatic force so that a large displacement may be obtained with little voltage to increase the ink discharge pressure.

1. Field of the Invention
The invention relates to a printer head, in particular to an inkjet head having an electrostatic actuator and a manufacturing method of the same.
2. Description of the Related Art
Operation types for inkjet heads include a thermal type and a piezoelectric type. For the thermal type, a heater is installed which can supply heat into the chamber by which a substantially large amount of thermal energy may be supplied in a short period of time, and bubbles are formed in the ink in the chamber so that the ink is sprayed out through nozzles. However, there are problems in durability, caused by repeated impact due to the pressure from the bubbles created by the heat; it is difficult to control the size of ink droplets; and there is a limit to increasing the printing speed.
Meanwhile, the piezoelectric type utilizes the piezoelectric property, which is force being generated when voltage is supplied, by attaching piezoelectric material on a diaphragm to apply pressure to the chamber of the head, so that the pressure provided to the chamber pushes the ink out. Since it involves applying pressure in the chamber via force generated by the voltage supplied, it yields excellent performance in terms of speed and is thus widely used.
FIG. 1 is a cross sectional view of a conventional piezoelectric type inkjet head. As in FIG. 1, a conventional piezoelectric type inkjet head comprises a substrate 7, a diaphragm 8, a piezoelectric element 9, partitions 10, and a nozzle plate 1. In a piezoelectric type inkjet head with such a configuration, the piezoelectric element 9 mechanically expands and contracts when control signals are sent to the piezoelectric element 9 from a control signal generator 4, with the expanding and contracting of the piezoelectric element 9 causing the ink 5 in the chamber 2 to be pushed out of the nozzle 3 as discharged ink droplets 6.
However, piezoelectric type inkjet heads are expensive, because they use costly piezoelectric elements, and the yield is low due to a complicated manufacturing process, since the piezoelectric elements must be carefully coordinated with the electrodes, insulation layer, and protection layer, etc.
To overcome the above problems, inkjet heads that use electrostatic force are currently in use. These inkjet printer heads are fast becoming the inkjet head type of choice because of such advantages as ease in manufacture, low power consumption, and simple mechanism.
FIG. 2 is a cross sectional view of a conventional electrostatic type inkjet head, as shown in FIG. 1 of U.S. Pat. No. 5,894,316, illustrating an inkjet head having a diaphragm. As illustrated in FIG. 2, a conventional electrostatic type inkjet head comprises a glass plate 11, a lower substrate 13 mounted with a constant gap from the glass plate 11, an upper substrate 16 mounted on the upper face on which is formed a nozzle 15 for the passage of ink discharge, a center substrate 14 placed between the upper substrate 16 and the lower substrate 13 and mounted on both sides of the lower substrate 13, and an ink chamber 17 enclosed by the above and forming a chamber wherein ink is stored. As shown in FIG. 2, another electrode is mounted on the lower surface 13 facing the electrode 12 mounted on the glass plate 11 with a gap G in between.
In an electrostatic type inkjet head with such a configuration, the two electrodes are oppositely charged when power is supplied, so that there is an attraction force pulling each other. Therefore, the electrode mounted on the ink-storing chamber is pulled toward the other electrode 12. When the power is shut off, the pulled electrode returns to its original state, which applies pressure to the ink inside the chamber. This pressure causes the ink to be discharged through the nozzle to the exterior.
In such an electrostatic type inkjet printer head, the ink chamber on which pressure is applied must be formed to be greater than a certain size, and to increase the electrostatic force and lower the rigidity of the thin film which acts as the electrode, the electrodes must have a large area facing each other. This causes an increase in the occupied area per nozzle and the nozzle intervals are made wider, so that there is a limit to increasing the resolution of the printer and the manufacturing costs are increased. Also, additional metal must be deposited to form the electrodes, which causes the manufacturing process to be more complicated.
Examples of existing techniques to improve ink discharge pressure in electrostatic type inkjet heads include, first, Korean patent no. 10-0242157 ('electrostatic actuator type inkjet printer head'). However, in this invention, the finger is protruded in one direction only, the diaphragm is pressurized by one electrostatic actuator, and the electrostatic actuator is secured only to the diaphragm, so that there is a limit to increasing electrostatic force.
A second example may be Japanese patent no. 2003-276194 ('electrostatic actuator, droplet discharge head, and inkjet printer device'). However, in this invention, the finger is protruded in one direction only, the actuator body is not partitioned by the frame into individual components, and electrostatic force is increased by superposing several layers for the flat plates of the operation electrode and the fixed electrode, so that a large displacement is not always obtained depending on the distance between electrodes.

Ink jet head having an electrostatic actuator, ink cartridge, and inkjet printer


A method for manufacturing a backside metalized compound semiconductor wafer includes the steps of: providing a compound semiconductor wafer; attaching the compound semiconductor wafer to a supporting structure; forming an adhesion layer including nickel and vanadium on a back surface of the compound semiconductor wafer; forming an alloy layer including titanium and tungsten on the adhesion layer; forming a metallization layer including gold on the alloy layer; and removing the supporting structure from the compound semiconductor wafer to obtain the backside metalized compound semiconductor wafer.

Semiconductor electronic devices, such as a heterojunction bipolar transistor (HBT) and a high electron mobility transistor (HEMT), have important applications in microwave technology, millimeter wave radiation, optoelectronics, etc. Manufacturers of advanced, multifunctional semiconductor electronic products should consider not only the performance of integrated circuit contained therein, but also reduction of manufacturing cost thereof.
Processing a back surface of a semiconductor wafer (i.e., back surface metallization) is one of the key steps in the manufacturing of the semiconductor electronic device. Regardless of the type and function of the semiconductor electronic device, it is necessary to provide a ground pad structure for transistors that are formed on a front surface of the semiconductor wafer. The ground pad structure includes a front metallization layer and a back metallization layer respectively disposed on the front surface and the back surface of the semiconductor wafer, and at least one via formed between and electrically connecting with the front and back metallization layers. Generally, the front metallization layer is first disposed on the front surface of the semiconductor wafer, and then the semiconductor wafer is subjected to mechanical grinding to reduce the thickness thereof. Afterwards, the via is formed from the back surface of the semiconductor wafer by an etching process (such as photolithography, dry etching and wet etching), followed by disposing the back metallization layer on the back surface of the semiconductor wafer to electrically connect the back metallization layer with the front metallization layer through the via. Due to such connection, the front metallization layer also functions as a heatsink by thermally conducting the heat generated by the semiconductor wafer.
After the back surface metallization, the thus disposed back metallization layer is subjected to photolithography to form a plurality of spaced-apart trenches, and then the semiconductor wafer is separated from a supporting material that holds the semiconductor wafer by heating or using solvent, followed by cutting (i.e., mechanical sawing) the semiconductor wafer along the trenches so as to obtain a plurality of semiconductor devices (i.e., dies). Photolithography is a cumbersome process with many steps for forming the back metallization layer, and requires chemical etching that involves use of chemical reagents and liquid waste treatment, while conventional mechanical sawing process is incapable of dicing the back metallization layer having a thickness of more than 5 μm. Usage of both of these processes would inevitably increase the time, cost and labor for manufacturing the semiconductor electronic device.
On the other hand, dicing process with a laser beam has been developed to directly cut the back metallization layer of the semiconductor wafer. However, such technique presents other problems in the manufacturing of a compound semiconductor device in which a metallization layer is formed on the back surface of a compound semiconductor wafer, such as in the manufacturing of a gallium arsenide wafer in which a titanium tungsten/gold composite layer is formed on the back surface thereof. For example, the peripheral region of the contact surfaces between the titanium tungsten/gold composite layer and the gallium arsenide wafer is susceptible to peeling after the dicing process due to weak van der Waals force formed therebetween, as well as non-uniform corrosion that causes discoloration, which subsequently affects the quality and reliability of the thus manufactured compound semiconductor device.

Method for manufacturing backside metalized compound semiconductor wafer

Xiamen Sanan Integrated Circuit Co., Ltd.


Methods and apparatus for optimizing IP multicast data transmission in a mobile IP environment include a Foreign Agent that is capable of receiving an information request associated with a host membership report sent from a mobile node and for providing information identifying a Home Agent associated with the mobile node to a multicast router process to enable the multicast router process to send a join host group message to the Home Agent. A Home Agent receives the join host group message and sends the join host group message toward a source of IP multicast data packets. Both the Foreign Agent and the Home Agent set up a data path between the Home Agent and the Foreign Agent, thereby enabling data packets addressed to the multicast group address to be forwarded by the Home Agent to the Foreign Agent. The Home Agent does not replicate multicast IP data packets addressed to the multicast group address prior to being forwarded by the Home Agent to the Foreign Agent. Rather, the multicast router process is responsible for replication and transmission of multicast IP data packets to one or more network segments associated with the Foreign Agent.

1. Field of the Invention
The present invention relates to Mobile IP network technology. More particularly, the present invention relates to optimizing the transmission of IP multicast data in a Mobile IP environment.
2. Description of the Related Art
Mobile IP is a protocol which allows laptop computers or other mobile computer units (referred to as xe2x80x9cMobile Nodesxe2x80x9d herein) to roam between various sub-networks at various locationsxe2x80x94while maintaining internet and/or WAN connectivity. Without Mobile IP or related protocol, a Mobile Node would be unable to stay connected while roaming through various sub-networks. This is because the IP address required for any node to communicate over the internet is location specific. Each IP address has a field that specifies the particular sub-network on which the node resides. If a user desires to take a computer which is normally attached to one node and roam with it so that it passes through different sub-networks, it cannot use its home base IP address. As a result, a business person traveling across the country cannot merely roam with his or her computer across geographically disparate network segments or wireless nodes while remaining connected over the internet. This is not an acceptable state-of-affairs in the age of portable computational devices.
To address this problem, the Mobile IP protocol has been developed and implemented. An implementation of Mobile IP is described in RFC 2002 of the Network Working Group, C. Perkins, Ed., October 1996. Mobile IP is also described in the text xe2x80x9cMobile IP Unpluggedxe2x80x9d by J. Solomon, Prentice Hall. Both of these references are incorporated herein by reference in their entireties and for all purposes.
The Mobile IP process and environment are illustrated in FIG. 1. As shown there, a Mobile IP environment 2 includes the internet (or a WAN) 4 over which a Mobile Node 6 can communicate remotely via mediation by a Home Agent 8 and a Foreign Agent 10. Typically, the Home Agent and Foreign Agent are routers or other network connection devices performing appropriate Mobile IP functions as implemented by software, hardware, and/or firmware. A particular Mobile Node (e.g., a laptop computer) plugged into its home network segment connects with the internet through its designated Home Agent. When the Mobile Node roams, it communicates via the internet through an available Foreign Agent. Presumably, there are many Foreign Agents available at geographically disparate locations to allow wide spread internet connection via the Mobile IP protocol. Note that it is also possible for the Mobile Node to register directly with its Home Agent.
As shown in FIG. 1, Mobile Node 6 normally resides on (or is xe2x80x9cbased atxe2x80x9d) a network segment 12 which allows its network entities to communicate over the internet 4 through Home Agent 8 (an appropriately configured router denoted R2). Note that Home Agent 8 need not directly connect to the internet. For example, as shown in FIG. 1, it may be connected through another router (a router R1 in this case). Router R1 may, in turn, connect one or more other routers (e.g., a router R3) with the internet.
Now, suppose that Mobile Node 6 is removed from its home base network segment 12 and roams to a remote network segment 14. Network segment 14 may include various other nodes such as a PC 16. The nodes on network segment 14 communicate with the internet through a router which doubles as Foreign Agent 10. Mobile Node 6 may identify Foreign Agent 10 through various solicitations and advertisements which form part of the Mobile IP protocol. When Mobile Node 6 engages with network segment 14, Foreign Agent 10 relays a registration request to Home Agent 8 (as indicated by the dotted line xe2x80x9cRegistrationxe2x80x9d). The Home and Foreign Agents may then negotiate the conditions of the Mobile Node""s attachment to Foreign Agent 10. For example, the attachment may be limited to a period of time, such as two hours. When the negotiation is successfully completed, Home Agent 8 updates an internal xe2x80x9cmobility binding tablexe2x80x9d which specifies the care-of address (e.g., a collocated care-of address or the Foreign Agent""s IP address) in association with the identity of Mobile Node 6. Further, the Foreign Agent 10 updates an internal xe2x80x9cvisitor tablexe2x80x9d which specifies the Mobile Node address, Home Agent address, etc. In effect, the Mobile Node""s home base IP address (associated with segment 12) has been shifted to the Foreign Agent""s IP address (associated with segment 14).
Now, suppose that Mobile Node 6 wishes to send a message to a corresponding node 18 from its new location. An output message from the Mobile Node is then packetized and forwarded through Foreign Agent 10 over the internet 4 and to corresponding node 18 (as indicated by the dotted line xe2x80x9cpacket from MNxe2x80x9d) according to a standard internet protocol. If corresponding node 18 wishes to send a message to Mobile Nodexe2x80x94whether in reply to a message from the Mobile Node or for any other reasonxe2x80x94it addresses that message to the IP address of Mobile Node 6 on sub-network 12. The packets of that message are then forwarded over the internet 4 and to router R1 and ultimately to Home Agent 8 as indicated by the dotted line (xe2x80x9cpacket to MN(1)xe2x80x9d). From its mobility binding table, Home Agent 8 recognizes that Mobile Node 6 is no longer attached to network segment 12. It then encapsulates the packets from corresponding node 18 (which are addressed to Mobile Node 6 on network segment 12) according to a Mobile IP protocol and forwards these encapsulated packets to a xe2x80x9ccare ofxe2x80x9d address for Mobile Node 6 as shown by the dotted line (xe2x80x9cpacket to MN(2)xe2x80x9d). The care-of address may be, for example, the IP address of Foreign Agent 10. Foreign Agent 10 then strips the encapsulation and forwards the message to Mobile Node 6 on sub-network 14. The packet forwarding mechanism implemented by the Home and Foreign Agents is often referred to as xe2x80x9ctunneling.xe2x80x9d
IP multicasting is the transmission of an IP packet to a xe2x80x9chost groupxe2x80x9d (i.e., multicast group), a set of zero or more hosts identified by a single IP destination address. RFC 1112 sets forth the recommended standard for IP multicasting on the Internet. Internetwork forwarding of IP multicast packets is handled by xe2x80x9cmulticast routersxe2x80x9d which may be co-resident with, or separate from, internet gateways. In addition, support for IP multicasting requires implementation of the Internet Group Management Protocol (IGMP). Thus, through IGMP, a node (e.g., receiver) may join a multicast group in order to receive packets addressed to that multicast group IP address.
FIG. 2 is a block diagram illustrating IP multicast data flow in a fixed environment. As shown, multiple receivers 202, 204, and 206 may be coupled to a single multicast router 208. For instance, each receiver may be associated with a television capable of receiving multicast data. When the receiver 202 wants to listen to a particular multicast group IP address, the receiver 202 sends an IGMP report. This may occur, for example, when a television viewer changes the channel on the television. An IGMP report, or xe2x80x9chost membership report,xe2x80x9d reports each host group to which the receiver belongs. In the normal case, only one report will be generated for each group present on the network by the first receiver to send such a report. This is sufficient since a multicast router need not know which hosts belong to a multicast group; only that at least one host belongs to a multicast group on a particular network. The host membership report indicates to the router 208 that multicast packets for that multicast group need to be replicated and forwarded. When the router 208 receives the IGMP report, the router 208 sends a join host group message toward a rendezvous point 210 which is recognized by both the receiver 202 and source 212. In other words, the rendezvous point 210 is established for communicating messages between the receiver 202 and the source 212. A join host group message specifies the multicast group address of the host group the receiver 202 wishes to join. In addition, the join host group message serves to request that the receiving network module accept and deliver subsequently arriving packets destined to the specified IP host group address. Moreover, the router 208 is aware of the location of the rendezvous point 210. The router 208 then sets up a data path between the router 208 and the rendezvous point 210 for the transmission and forwarding of multicast data from the rendezvous point 210 to the router 208. Thus, when the source 212 sends streaming data (e.g., television channel or stock information) to the rendezvous point 210, the rendezvous point 210 forwards the data to the router 208. The router 208 then makes copies of the packet and sends the packet to each subnet with receiver that has joined that particular multicast group. In this example, the router 208 sends the packet to the receiver 202. If any other receivers (e.g., 204, 206) have joined the multicast group, copies of the packet are sent to these receivers as well, if they are on different subnets.
It is important to note that for multicast data transmission, packets must be replicated for transmission to the appropriate receivers. However, in a Mobile IP environment, the designated method of replication of packets is specifically addressed by RFC 2002. RFC 2002 defines a method to support IP multicast data transmission in a Mobile IP environment. More particularly, RFC 2002 specifically requires that the Home Agent replicate broadcast and multicast data packets for transmission to multiple devices (e.g., mobile nodes) destined to receive the packets.
Although RFC 2002 enables IP multicast data to be transmitted in a Mobile IP environment, this method is sub-optimal, since it requires the Home Agent to duplicate multicast packets for transmission to each mobile node via a tunnel to the Foreign Agent. This replication by the Home Agent is required, even if all mobile nodes are visiting the same Foreign Agent. It is important to note that the distance between the Home Agent and the Foreign Agent may be substantial, consuming network bandwidth and switch processing during the replication process. In view of the above, it would be desirable to optimize IP multicast data transmission in a Mobile IP environment.
The present invention optimizes the transmission of IP multicast data in a mobile IP environment. This is accomplished by performing packet replication and transmission at the Foreign Agent or associated multicast router rather than at the Home Agent. In order to modify the packet replication process, the present invention provides a mechanism for establishing a data path between the Foreign Agent and the Home Agent that enables this method of packet replication and transmission.
In accordance with one aspect of the invention, a Foreign Agent is configured to establish a data path between the Foreign Agent and a Home Agent, where the data path is adapted for transmission of multicast IP data packets from the Home Agent to the Foreign Agent so that the multicast data packets may be transmitted to one or more mobile nodes visiting the Foreign Agent. The Foreign Agent receives an information request associated with a host membership report sent from a mobile node, where the host membership report specifies a multicast group address identifying a host group to which the mobile node belongs. For example, the information request may ask whether the mobile node is allowed to join the host group, it may indicate that information identifying the Home Agent is requested from the Foreign Agent, and/or it may ask whether the mobile node is visiting the Foreign Agent. In response to this information request, the Foreign Agent provides information identifying the Home Agent associated with the mobile node to a multicast router process, thereby enabling the multicast router process to send a join host group message to the Home Agent. The join host group message specifies the multicast group address and operates to request that the Home Agent accept and deliver subsequently arriving multicast data packets destined to the multicast group address to the Foreign Agent.
In accordance with another aspect of the invention, a multicast router implements a multicast router process. The multicast router is adapted for receiving a host membership report sent from a mobile node. The multicast router then sends an information request associated with the host membership report to a Foreign Agent that the mobile node is visiting. For instance, the information request may request information identifying a Home Agent of the mobile node or it may ask the Foreign Agent whether the mobile node is visiting the Foreign Agent. The multicast router is further configured to receive any information identifying the Home Agent from the Foreign Agent. In addition, the multicast router may send ajoin host group message to the Home Agent, where the join host group message specifies the multicast group address and requests that the Home Agent accept and deliver subsequently arriving packets destined to the multicast group address to the Foreign Agent. For instance, the join host group message may be sent to the Home Agent when the mobile node is visiting the Foreign Agent.
In accordance with yet another aspect of the invention, a Home Agent is configured to establish a data path between a Foreign Agent and the Home Agent, where the data path is adapted for transmission of multicast IP data packets from the Home Agent to the Foreign Agent so that the multicast data packets may be transmitted to one or more mobile nodes visiting the Foreign Agent. The Home Agent is configured to receive ajoin host group message and send the join host group message toward a source of multicast IP data packets. The Home Agent then sets up a data path between the Home Agent and the Foreign Agent, thereby enabling packets addressed to the multicast group address to be forwarded by the Home Agent to the Foreign Agent. Thus, the Home Agent may forward multicast data packets using a single encapsulation step since the Home Agent is not responsible for replication of the multicast data packets.

Optimizing IP multicast data transmission in a mobile IP environment


Initial mask and waveform positions on a display screen may be determined by an AUTOSET TO MASK function. Upon detection of violations that occur after the AUTOSET TO MASK function is complete, control for further alignment of the waveform under test and the mask is assumed by an AUTOFIT TO MASK function. Comparison of the mask pixels and waveform pixels to detect collision between a waveform pixel and a mask pixel (i.e., a mask violation) is performed substantially in real time, as the pixels are being composited into the raster memory by the rasterizer. In the event of a mask violation, a mask violation signal is generated. In a further embodiment of the invention, in response to the mask violation signal, the AUTOFIT TO MASK function uses display rasterization to automatically redraw the waveform at a new location, until the waveform fits within the mask. In yet another embodiment, in response to the mask violation signal, the AUTOFIT TO MASK function automatically redraws the telecom mask at a new location until the waveform fits within the mask.

The subject application is related to U.S. patent application Ser. No. 09/607,573 filed on Jun. 29, 2000, entitled A TEST AND MEASUREMENT INSTRUMENT HAVING TELECOMMUNICATIONS MASK TESTING CAPABILITY WITH A MASK ZOOM FEATURE, (Letts) assigned to the same assignee as the subject application, and also claiming priority from the above-identified U.S. Provisional application, and to U.S. patent application Ser. No. 09/619,067 filed on Jul. 19, 2000, entitled A TEST AND MEASUREMENT INSTRUMENT HAVING MULTI-CHANNEL TELECOMMUNICATIONS MASK TESTING CAPABILITY, (Letts and Herring), assigned to the same assignee as the subject application, and also claiming priority from the above-identified U.S. Provisional application.
The subject invention generally concerns test and measurement instruments, and in particular concerns those test and measurement instruments employing telecom mask features.
In the telecommunications industry, it is commonplace to perform a test to determine if a particular signal is in compliance with parameters established by national and international communications standards bodies such as ITU-T and ANSI. A primary way to perform such a compliance test is to compare the pulse shape of a waveform acquired by an oscilloscope to a waveform xe2x80x9cmaskxe2x80x9d. The mask defines a pathway having minimum and maximum amplitude values, predetermined bit rate, and defined minimum slope on signal edges (i.e., minimum bandwidth). If the signal under test stays within the pathway boundaries, then the signal passes the test. This kind of test is known as Telecom Mask Testing.
A recent innovation in oscilloscope features has been a xe2x80x9cAUTOSET TO MASKxe2x80x9d function. The AUTOSET TO MASK function automatically sets up the horizontal, vertical, and triggering settings on the oscilloscope to accommodate the expected signal, and overlays a mask on the oscilloscope display. The procedure followed in the operation of an AUTOSET TO MASK function is to set the horizontal and vertical scales to a nominal value, acquire a waveform, and adjust the scale and position of the waveform by adjusting the settings of the input A/D converters, and display the mask. Unfortunately, it has been observed that the AUTOSET TO MASK function sometimes places the mask on the display with an undesired offset in the vertical or horizontal directions. The likelihood of incorrect placement of the mask depends upon several factors including the shape of the signal being acquired and the particular algorithm used to implement the AUTOSET TO MASK.function.
It should be understood that an AUTOSET TO MASK function merely sets up the acquired waveform and displays the mask. It does not check for intrusions into the mask area by the waveform being tested (i.e., violations, or mask hits). Thus, the AUTOSET TO MASK function does not provide correction for such violations.
In this regard, note that telecommunications standards often allow some tolerance in vertical offset for the communications signal. That is, telecommunications standards are usually more concerned (i.e. exhibit tighter tolerances) with respect to other signal characteristics, such as pulse width, and rise time. If the telecom mask is incorrectly placed due to such an offset, an otherwise perfectly acceptable signal (i.e., one that should have passed) will unnecessarily fail when it is later tested for intrusions into the mask area.
One prior art response to this problem was a software solution used in the Tektronix 2400 DITS (Digital Interface Test System), manufactured by Tektronix, Inc., Beaverton, Oreg. In this arrangement, a waveform was acquired by the oscilloscope, rasterized, and stored. Each pixel of the rasterized waveform is indexed to a particular list of vertical segment points occupied by the mask at that particular horizontal (i.e., time) position. Thereafter, the individual pixels of the rasterized waveform were read out and compared, one by one, with the corresponding vertical array of mask segment locations to see if pixels in the mask area and the waveform coincided. If so, a xe2x80x9cmask hitxe2x80x9d was said to have occurred. This purely software solution counted the number of xe2x80x9cmask hitsxe2x80x9d that occurred, and repositioned the mask (horizontally or vertically on the display) until the number of mask hits was reduced to zero. This assumes, of course, that the signal under test did, in fact, correspond to the applicable standard. It is important to note that this prior solution did not operate in real time but rather post-processed the rasterized waveform data.
While this solution does perform extremely well for ensuring compliance with standards for low speed telecommunication signals, it tends to be software intensive and time consuming. What is needed is a faster, less software intensive solution to the problem of properly registering the telecom mask with respect to the signal under test.
Initial mask and waveform positions on a display screen may be determined by an AUTOSET TO MASK function. Upon detection of violations that occur after the AUTOSET TO MASK function is complete, control for further alignment of the waveform under test and the mask is assumed by an AUTOFIT TO MASK function. Comparison of the mask pixels and waveform pixels to detect collision between a waveform pixel and a mask pixel (i.e., a mask violation) is performed substantially in real time, as the pixels are being composited into the raster memory by the rasterizer. In the event of a mask violation, a mask violation signal is generated.
In a further embodiment of the invention, in response to the mask violation signal, the AUTOFIT TO MASK function uses display rasterization to automatically redraw the waveform at a new location, until the waveform fits within the mask.
In yet another embodiment, in response to the mask violation signal, the AUTOFIT TO MASK function automatically redraws the telecom mask at a new location until the waveform fits within the mask.

Test and measurement instrument having telecommunications mask testing capability with an autofit to mask feature