A data/video server having the following elements: n I/O access channel connectors, m storage arrays and a commutator which connects individual ones of the I/O access channel connectors to different individual ones of the storage arrays in accordance with a connection diagram with which the server is being operated in accordance with at a given time, further includes a system (operating in accordance with a method) for enabling it to implement operation in accordance with a new connection diagram (which can enable the bandwidth provided to one or more I/O access channels coupled thereto to be changed). That system includes a bandwidth manager for generating a new connection diagram; and a control system, coupled to the bandwidth manager, for obtaining the new connection diagram and causing the elements of the server to implement operation in accordance with the new connection diagram. The bandwidth manager is included in one of the storage arrays, and the control system is made of microprocessors which are individually included in each of the different elements of the server. First counters are included in each of the elements to aid in synchronizing those elements so that they can implement operation in accordance the new connection diagram at substantially the same time. Second counters are included in the elements to aid the microprocessors ensuring that as the elements implement operation in accordance with the new connection diagram, by begin operating in accordance therewith, the beginning of such operating is subject to and in accordance with one or more transition rules. The server also includes a counter signal generator for incrementing the first and second counters when appropriate.

1. Field of the Invention
The invention relates to a system and method which enable a data/video server to modify the bandwidth provided to one or more I/O (input/output) access channels coupled thereto. In particular, the invention relates a system and method which enable a data/video server to implement operation in accordance with a new connection diagram so that bandwidth requirement changes of one or more I/O access channels coupled thereto can be satisfied, and a data/video server including that system.
2. Description of the Related Art
Data/video servers such as the Media Pool video server developed by Philips Broadcast Television Systems Company (a division of Philips Electronics North America Corporation) contain a plurality of I/O (input/output) access channel connectors, a commutator and a plurality of storage arrays (each containing a plurality of disc drives therein) for use in storing and/or retrieving data from and/or to, respectively, one or more I/O access channels coupled to the I/O access channel connectors. The Media Pool video server, in particular, operates, via a control system (also contained therein), in accordance with the following rules of operation:
(1) Each individual I/O access channel connector is connected, via the commutator, to each of the storage arrays individually once in some sequence during a time period associated therewith, during which time period there may be one or more sub-periods in which that I/O access channel connector is not connected to a storage array (such connection of an I/O access channel connector to each of the storage arrays during such a time period is hereinafter referred to as a "CTA", i.e., connect-to-all). More particularly, each individual I/O access channel connector is connected, via the commutator, to each of the storage arrays individually once in a specific predetermined pattern (which is the same for all of the I/O access channel connectors) during a constant time period T.sub.b associated therewith, during which time period T.sub.b that I/O access channel connector is always connected to one of the storage arrays (such connection of an I/O access channel connector to each of the storage arrays during such a time period T.sub.b is hereinafter referred to as a "BLAST", which is sub-class of a CTA in which the pattern of connection is in accordance with a predetermined order and there are no sub-periods during that time period T.sub.b in which an I/O access channel connector associated therewith is not connected to a storage array. (Examples of CTAs and BLASTs are shown and discussed below in conjunction with FIG. 3.) PA1 (2) Multiple I/O access channel connectors can be connected to multiple storage arrays at a time, but during that time only one of the I/O access channel connectors can be connected to a given one of the storage arrays, and only one of the storage arrays can be connected to a given one of the I/O access channel connectors. PA1 (3) All of the I/O access channel connectors are individually connected to all of the storage arrays individually once during a constant time period T.sub.a.
This manner of operation allows the I/O access channels coupled to a Media Pool video server to substantially simultaneously provide data for storage in the storage arrays, receive the same (or different) data from the storage arrays or a combination of both.
The initial Media Pool video server was a symmetrical server, i.e., it contained the same number of I/O access channel connectors and storage arrays. Its manner of operation included having, at all times, each of the I/O access channel connectors (a) connected to a different one of the storage arrays and (b) continuously involved in performing BLASTs. This, in turn, meant that during each successive non-overlapping time period T.sub.a =T.sub.b, associated with any one of the I/O access channel connectors, each of the I/O access channel connectors was individually connected to each of the storage arrays individually once in the same pattern. For a more detailed discussion of the initial (symmetrical) Media Pool video server, reference is made to U.S. Pat. No. 5,539,660 and U.S. application Ser. No. 08/389,672, filed Feb. 16, 1995, which are incorporated herein by reference.
Although the initial Media Pool video server optimized the usage of the I/O access channel connectors and the storage arrays (by always having each of the I/O access channel connectors connected to a different one of the storage arrays and involved in performing BLASTs), it failed to allow the bandwidth of the I/O access channels coupled to the I/O access channel connectors to be different. On the contrary, because of its manner of operation, the bandwidth of each of the I/O access channels coupled to the I/O access channel connectors of the initial Media Pool video server was the same.
This problem, however, has be solved by the introduction of a newer current Media Pool video server which can operate as an asymmetrical server, i.e., it can contain a different number of I/O access channel connectors and storage arrays. (It should be noted that the current Media Pool video server can also be operated as a symmetrical server as well, but it employs the operating mechanism discussed in the next paragraph.) Like the initial Media Pool video server, the current Media Pool video server also follows the above-mentioned rules of operation. However, because it is not possible in all cases for each of the I/O access channel connectors of an asymmetrical Media Pool video server to be connected to a different one of the storage arrays all of the time or to always be continuously involved in performing BLASTs, as was the case with the initial Media Pool video server, an operating mechanism was introduced which not only enables the current Media Pool video server to follow the above-mentioned rules, but also enables it to provide different bandwidth to different ones of the I/O access channels coupled thereto.
The operating mechanism by which the current Media Pool video server achieves the above is by operating the server during successive cycles, each having a time period T.sub.s (.gtoreq.T.sub.a) (and hereinafter referred to as a supercycle"), in which in each supercycle each of the I/O access channel connectors is connected, via performing one or more CTAs (and to the extent possible, BLASTs), to each of the storage arrays for a sufficient amount of time so that each of the I/O access channels coupled to the I/O access channel connectors is provided with a sufficient amount of bandwidth to meet its needs during that supercycle. By operating in accordance with this mechanism, the current Media Pool video server can be programmed to operate in a manner whereby it provides different I/O access channels coupled thereto with different bandwidth. For a detailed description of this operating mechanism and an asymmetrical Media Pool video server, reference is made to the above-mentioned U.S. application Ser. No. 08/389,672 (see in particular FIGS. 11 and 12 and the discussion associated therewith).
Prior to the invention disclosed herein, it was believed that a current Media Pool video server needed to be programmed, prior to being brought on-line, i.e., booted-up, so that it would operate continuously in exactly the same manner supercycle after supercycle, i.e., in a static manner, until taken off-line. Furthermore, it was believed that when such a server was programmed, it had to be programmed, not only so that it would operate in a manner whereby it provides each of the I/O access channels with sufficient access, via the I/O access channel connectors, to the storage arrays during a supercycle to satisfy its bandwidth needs, but also, so that it would maximize the interconnections, via CTAs (and to the extent possible, BLASTs), of the I/O access channels connectors and storage arrays during that supercycle and leave little if any potential bandwidth unused during that supercycle. (Such a programming configuration can be represented by a connection diagram showing the number and placement of the CTAs and BLASTs performed by each of the I/O access channel connectors across the storage arrays during a supercycle. An example of such a diagram can be found in FIG. 12 of the above-mentioned U.S. application Ser. No. 08/389,672.)
The above-described static manner of operation of a current Media Pool video server and/or its operational programming to utilize substantially all of the potentially available bandwidth during a supercycle would have made it impossible for it to adapt to situations where the bandwidth needs of one or more of the I/O access channels coupled thereto change over time, e.g., when new or different applications are to be run, without having to be taken off-line and reconfigured. Shutting down a current Media Pool video server, reconfiguring it and then bringing it back on-line, i.e., rebooting it, to meet changing bandwidth needs of one or more of the I/O access channels coupled thereto is impractical, and in some situations unthinkable.
Accordingly, prior to the invention disclosed herein, there was a need to be able to change the operational programming configuration of the current Media Pool video server while on-line. Furthermore, it was realized that any such operational programming configuration change(s) would need to be done in a manner which would enable the current Media Pool video server to continue to operate properly during and after such operational programming configuration change(s).

System and method for enabling a data/video server to implement operation in accordance with a new connection diagram, and a data/video server including that system


A beverage holder is provided. The beverage holder may include a strap assembly connected to a beverage assembly. The beverage assembly is adapted to retain beverage containers therein. The strap assembly may include a first strap member and a second strap member. The first strap member may terminate in an arm loop and an opposing clasp end. The clasp end may form a clasp loop for securing a strap clasp. The second strap member may terminate in an arm loop and an opposing return end. The return end may provide both of one half of a mating hook-and-loop combination. The hook portion and the loop portion may be securely engaged to form a return loop, whereby the overall desired length of the entire resulting strap assembly may be varied by adjusting the portion of the hook portion that overlaps the loop portion. A user may place each arm loop over each of a pair of armrests, whereby both strap members are routed around the backrest so as to slide the return end through the strap clasp. Then the user may fold the return end to form the return loop by mating the hook and the loop portion so as to define the desired length of the entire resulting strap assembly and tightness about the backrest.

The present invention relates to beverage holders and, more particularly, to beverage holders for passenger use on motorcycles with a back rest with an armrest.
Currently, there are no easily mounted beverage holders for passengers on motor vehicles with standard armrest backrest, such as Harley Davidson motorcycles, wherein such beverage holders do not require modifying the motor vehicle, do not make the beverage hard to reach, do not detract from the aesthetic of the motor vehicle and do not hold the beverage near the vehicle's engine. Other passenger beverage holder systems require drilling, clamping or gluing of hardware to be mounted, thereby requiring modifying the motor vehicle, as well as detracting from the vehicles appearance. Other systems also hold the beverage in places that are difficult for the passenger to reach or hold the beverage near the hot engine, undesirably warming the beverage.
As can be seen, there is a need for a vehicle beverage holder that can be easily deployed, easily removed, easy to reach and does not require a destructive mount or otherwise detracts from the appearance of the underlying vehicle.


A method for generating a simulated network. A network discovery database for a managed network is accessed, wherein the network discovery database includes device information and connectivity information for a plurality of devices of the managed network. A build file describing the simulated network is automatically generated based on the network discovery database. A user is able to create and edit a simulated network based on an actual managed network, thereby obviating the need for manually coding a simulated network.

In a large enterprise with a large number of computing devices, the networking infrastructure can be extraordinarily complex. For example, a network of a large enterprise may include five to ten thousand network devices as well as thousands of end-stations or "hosts". Network management systems are typically employed to monitor the network in order to ensure that the network is functioning properly.
In order to ensure proper functioning of a network management system, it is necessary to test the network management system while connected to a network. In the past, the network management system would often be connected to a network of a live customer enterprise to conduct these tests. However, due to security and network disruption concerns, enterprises are no longer open to this sort of testing.
Currently, one way to test a network management system is to set up an actual network in a laboratory. For example, a network of ten to one hundred devices can be set up, and the network management system is used for monitoring the network. This method assumes that if the network management system works for a network of up to one hundred devices, it will work for a network of several thousand devices. However, this assumption is not always valid, as network complexity gets much greater as the number of devices increases.
Another way for testing a network management system is to connect the network management system to a simulated network. A simulated network is typically a data file and software system that is able to convince the network management system that it is connected to and monitoring an actual network. Network simulation tools exist for assisting a user in creating a simulated network. Specifically, typical network simulation tools allow a user to specify devices of the simulated network. However, it is necessary for the user to manually enter in connection information for each device. That is, a configuration file that identifies the connections between the devices must be created or edited for each device. For simulating a large network of several thousand devices this is very time consuming, thereby consuming substantial human and financial resources of the enterprise.

Method for generating a simulated network based on an actual managed network


A noninvasive system for monitoring the oxygen saturation level of a person subjected to reduced atmospheric pressure for avoiding hypoxemia. The system monitors a person's oxygen saturation level, comparing the saturation level to a predetermined level. When the measured saturation level is less than the predetermined level, the person is then supplied with an oxygen mixture for increasing the subject's oxygen saturation level to a safe level. The person's exposed reduced atmospheric pressure is also compared with a predetermined range of pressure levels. If this predetermined range of pressure levels is exceeded or maintained for a predetermined time duration, the person is then supplied with an oxygen mixture. Additionally, a device is provided for performing oxygen flight planning calculations for estimating oxygen usage for a predetermined flight plan that is based on the above system.

Ascent to altitude by use of airborne craft was initially achieved by hot air balloon. The first passengers carried beneath the Mongolfier brothers balloon during a 1782 flight were a duck, a rooster and a sheep, as the effects of flight for a person were unknown. At least one hundred years later, the physiological effects due to unpressurized high altitude flying remained largely unknown. In 1875, a three man balloon crew first employed a supplemental oxygen source consisting of three goatskin bags connected to a centered wash bottle providing 72 percent oxygen totaling 440 liters. The balloon flight reached 28,000 feet in altitude. While attempting to conserve oxygen during the flight, the three men were overcome by a euphoric torpor induced by lack of oxygen, resulting in the deaths of two of the men. The survivor later recorded that when convinced of the need of oxygen, he was powerless to raise his arms, unable to raise the mouthpiece of the oxygen container to his lips, and though within easy reach, the oxygen which would have saved the lives of his companions went unused. An insufficiency of oxygen in the blood is defined as hypoxemia, while an insufficiency of oxygen in the body tissue is defined as hypoxia.
To address the adverse effects of in-flight oxygen deficiency, oxygen distribution systems were incorporated into aircraft. Pre-World War II pipe stem oxygen distribution systems were later replaced by pressure clearance systems at the end of the conflict. Soon after, constant flow masks were made available in general aviation. While initial commercial air transport in the United States in the 1930's did not raise a significant risk of hypoxia because of low flight altitudes, by the 1940's to 1960's, the service ceiling of commercial aircraft was at 40,000.
Each person has a different oxygen requirement and adaptation to altitude, and those requirements change on a daily, or more accurately, an hourly basis based upon fatigue, diet, hydration level, stress and other personal factors. Increases in altitude likewise increase the associated adverse effects, including changes in visual acuity, psychomotor performance and situational awareness. As altitudes increase above 10,000 feet and critically above 15,000 feet, the time of useful consciousness (TUC) decreases at 15,000 feet to 15-20 minutes. As expected, there is a difference in the physical fitness standards between commercial/military pilots and general aviation pilots and passengers.
The Federal Aviation Administration (FAA), mindful of the adverse effects to passengers and crew of aircraft operating at altitude, has developed regulations concerning the availability and use of sustenance and supplemental breathing oxygen. These regulations are divided into the following classifications: air transport, on-demand operations and general aviation. The regulations relating to general aviation are discussed herein. The term "passengers" or "occupants" as used herein may also include the pilot and crew of the aircraft. The term "subject" as used herein may refer to any person in the aircraft. The current regulations are based on rules initially established by empirical data and experience of the Civil Aviation Administration (CAA).
Requirements for general aviation supplemental oxygen is provided in 14 CFR 91.211 as cited in the Federal Register dated Aug. 23, 2001. While this regulation provides for aircraft having pressurized and unpressurized cabins, most of the single engine piston powered general aviation aircraft used under Part 91 of the regulations employ unpressurized cabins, which is the primary focus herein. 14 CFR 91.211 provides that supplemental oxygen shall be provided to a required minimum flight crew above cabin pressure altitudes of 12,500 feet, mean sea level (MSL), up to and including 14,000 feet MSL if the duration of the flight at that altitude is more than 30 minutes. Cabin pressure altitude is calculated by taking a pressure measurement inside the aircraft cabin and converting that pressure to an altitude, preferably by a device that performs this calculation automatically. At cabin pressure altitudes above 14,000 feet MSL, the required flight crew must be provided with and use supplemental oxygen. MSL altitude is the atmospheric pressure either directly measured by weather stations at sea level or empirically determined from the weather station pressure and temperature readings collected by weather stations not at sea level. At cabin pressure altitudes above 15,000 feet MSL, supplemental oxygen must be provided to each occupant of the aircraft. In other words, FAA regulations do not require providing supplemental oxygen to occupants (passenger that are not required flight crew) below 15,000 feet MSL.
It is noted that other FAA regulations under Title 14, such as Parts 121 and 135, relate to air transport and on-demand operations, which specify different, more stringent altitude requirements with respect to supplemental oxygen use for pilots. In other words, the altitudes triggering the requirements for supplemental oxygen are greater for general aviation use. For example, 14 CFR 135.89 provides that the minimum altitude is 10,000 feet MSL instead of 12,500 feet MSL for the pilot or flight crew. The time for the required crew to use supplemental oxygen is the same 30 minute duration. As a result, many pilots may be lulled into believing that the time they spend at higher altitude is of little concern and to "push the envelope," accepting higher altitudes when filing flight plans or maximizing the operational capabilities of their turbocharged piston powered engines without the use of supplemental oxygen. This misguided thinking has often concluded tragically. Flying at altitudes as low as 5,000 feet can affect certain individuals, particularly at night. It is estimated that pilot error is the primary cause of about 74 percent of all general aviation accidents. To understand how the present invention utilizes generally accepted clinical standards for hypoxemia, which can be easily and reliably determined and applied to help prevent hypoxia, a brief summary of human oxygen physiology is provided below.
Oxygen that is inspired through the mouth or nose proceeds down the trachea and into the main bronchi, flowing out into primary and secondary bronchi and then into the alveolar air units. The space between the mouth and the alveolar units is "dead space" because there is no air exchange in these tubes. In other words, that portion of air previously inspired only reaching this dead space retains its oxygen content and may again be inspired for air exchange. Oxygen and carbon dioxide exchanged in the alveolus is dependent on the diffusion capacity, which can be affected by age and chronic disease.
Ventilation and oxygen supplied for aerobic cellular respiration, is accomplished in the alveolar units which diffuses oxygen across the pulmonary membrane into capillary beds, the diffused oxygen in the alveolar units passing through the pulmonary cells into the pulmonary venules then into the pulmonary vein. Pressurized carbon dioxide (PCO2) from the body flows from the pulmonary artery into the capillaries, then to the alveolar unit, where it similarly diffuses through the pulmonary membrane and is expired as a waste gas. The volume of air moved through the pulmonary units is known as minute ventilation with vital capacity being the total volume of the lung.
The actual air that we breathe is a combination of different gases at various pressures P. The pressure of oxygen (PO2) is 159.1 torr in dry air, 149.2 torr in moist tracheal air at 37° C., 104 torr in the alveolar gas unit, 100 torr in arterial blood and 40 torr in mixed venous blood out of a total 760 torr at standard conditions. Thus, PO2 as used herein may be defined to refer to the oxygen pressure level corresponding to ambient, tracheal or alveolar as appropriate to apply or calculate other physiologic parameters. In addition to PO2, the partial pressures of CO2 and H2O and N2 are necessary to calculate the total and partial pressures of gases acting on the pilot (FIG. 5). The term torr refers to the pressure required to support a column of mercury 1 mm high under standard conditions, that is, standard density of mercury and standard acceleration of gravity. These conditions are at 0° C. and 45° latitude with acceleration of gravity is 980.6 cm/sec2, torr is a synonym for "mm/Hg". An important constant to remember is the partial pressure of water vapor, for the trachea will always have a PH2O of 47 torr as inspired air will be saturated with water vapor as soon as it is inspired. Therefore only 760 torr-47 torr or 713 torr of pressure is available for the sum of pressures of oxygen, carbon dioxide and nitrogen at standard conditions of 0° C. and 45° latitude. Water vapor pressures increase with temperature, for example 20° C. has PH2O of 17.5 torr while 37° C. has PH2O of 47 torr. The PO2 of moist inspired air in the trachea is actually 149 torr, which is 20.93% of 713 torr. While the trachea will always have a PH2O of 47 torr, what of the environment from which the inspired gases are drawn into the airway of the pilot of an unpressurized aircraft at 10,000 feet MSL? As the aircraft climbs, the partial pressure of O2 and the temperature will fall with increasing altitude. Although air vents of the aircraft cabin are open to the cooler outside environment at increased altitude, typically the aircraft cabin air that is inspired by the aircraft passengers is heated and maintained at an elevated temperature for passenger comfort. Concomitantly, the ground barometric pressure and temperature will change as the aircraft navigates a course. These changes alter the baseline assumptions in actual partial pressure of gases at the indicated altitudes (IA) of the aircraft. In a pressurized aircraft such as a commercial transport aircraft pressurized at 4,000-8,000 feet MSL, a constant cabin temperature and a cabin pressure can be maintained. Over the time of a cross-country flight with decreased cabin pressure, the pilot and passenger(s) will notice lower extremity edema from lower cabin pressure relative to sea level.
For purposes herein, the pilot lung alveolar gas compartment is a critical volume. During respiration pilots expire CO2 and absorb O2 gases. The quantity (CO2 ml excreted/ml O2 absorbed) is the respiratory ratio R which gives a mean estimate of PO2 and PCO2 over time. The mean alveolar O2 (PAO2) at sea level and 37° C., is defined in equation 1
                              PAO          2                =                                            FIO              2                                                  (              713              )                                -                                    PACO              2                                                  [                                                FIO                  2                                +                                                      1                    -                                          FIO                      2                                                        R                                            ]                                                          [        1        ]            where FIO2 is the fraction of inspired O2 (percent), and PACO2 is the mean alveolar CO2. Recall that the total pressure of all alveolar gases at sea level is 760 torr. Pilot lung volumes and actual cabin altitudes will be discussed in additional detail below. As the altitude increases, the FIO2 remains relatively constant at 21%, the PAO2 decreases as the barometric pressure decreases with altitude (at 18,000 feet MSL; 50% of atmospheric pressure at sea level is absent). Therefore, the partial pressures of all gases decrease with increasing altitude. As hypoxemia is defined as the lack of adequate oxygen supply in the blood, individual pilot hypoxemia can occur at an altitude where the oxygen supply for the individual pilot is inadequate for the pilot physiologic oxygen demand. The key factor is not a specific aircraft altitude MSL but rather the oxygen demand of the pilot. The diffusion capacity of the gases varies with the individual, dependent on the current status of the health of the pilot's lung alveolus. The oxygen diffuses from the alveolus to the venue capillary into the blood serum and then is absorbed by the red cell and stored there for transport in the body.
The components of the oxygen transport system are comprised of cardiac output of the heart (CO), the hemoglobin concentration of the blood (Hb), oxygen red cell saturation of the red blood cells (SAO2) for arterial circulation, (SVO2) for venous circulation, and the oxygen consumption of the body (VO2). Oxygen saturation is defined as the percentage of oxygen bound hemoglobin to the total amount of hemoglobin available. Oxygen saturation in the blood may be measured by a co-oximeter in the pulmonary laboratory.
Invasive medical oxygen moniters or oximeters, such as those originally manufactured by Oximetrix Inc., of Mountain View, Calif., may include a catheter, an optical module and a digital processor. The catheter, such as a pulmonary artery catheter typically includes a balloon on a distal tip for flow-directed placement, and a proximal lumen, which is a thermistor similar to a standard pulmonary artery thermodilution catheter, and two optical fibers. One fiber transmits light from the optical module to the distal tip of the catheter while the second fiber returns the reflected light from the distal tip back to the optical module. The Oximetrix optical module contains three light emitting diodes (LED's) that illuminate, via one optical fiber, the blood flowing past the catheter tip. Light reflected from the blood is returned through the second fiber and directed into a solid state photodiode detector within the optical module. The module converts the light intensity levels into electrical signals for transmission to the processor. The digital processor computes percent of oxygen saturation values based on the electrical signals transmitted and received from the optical module. These values are continuously displayed in numerical form by LED and are recorded by the processor's built-in strip recorder. Later models have LED display only but functionally are the same unit.
Oximeters have been used under clinical conditions, especially for monitoring oxygen saturation levels of critically ill patients. However, catheters, such as Opticath® catheters which are used with Oximetrix oxygen monitors, are invasive as the catheter must be inserted inside the pulmonary artery. Alternately, oxygen saturation may also be measured transcutaneously using infrared light in pulse oximetry units. Pulse oximeters similarly employ an LED and photosensor placed on opposite sides of arterioles located in a subject's tissue that can be transilluminated. In other words, pulse oximeters may be positioned over a narrow portion of a subject's anatomy, such as a finger or ear lobe. Typically, the pulse oximeter "clips" over opposed sides of the end of an appendage, such as an index finger. Pulse oximeters have many advantages over Opticath® catheters. They are noninvasive, as the subject's skin is not pierced, require no calibration, provide nearly instantaneous readings, rarely provide false negative information, require no routine maintenance, and are relatively inexpensive to purchase. These units are accurate in normal physiologic states, although in clinical situations of hypoprofusion and hypothermia the transcutaneous oxygen saturation measurements are inaccurate. Oxygen saturation measured in a pulmonary artery by either direct blood measurement (blood gas studies) or fiber-optic pulmonary artery catheter (co-oximetry) or pulse oximetry is generally accurate within 2% of the actual value.
Co-oximetry and pulse oximetry provide measurements of hemoglobin saturation. Molecular oxygen is carried within the hemoglobin molecule to tissues in the body, the oxygen carrying capacity possibly varying over time in response to changing health and/or environmental conditions. Normal hemoglobin carries 98% of the oxygen within the hemoglobin molecule with approximately 2% of the oxygen in the blood serum. This, however, can change significantly in diseases such as sickle-cell anemia (HbSS>50%) in which there is abnormal sickling of the hemoglobin molecule and decrease in oxygen carrying capability. This can be aggravated in periods of hypotension and dehydration even in sickle cell trait (HbSS<50%). Oxygen transport (O2T) occurs best at hemoglobin values of 40-43%. At hematocrit values greater than 50%, the result is increased viscosity and sluggishness of the blood, whereas hematocrit values less than 40% have the result of decreased hemoglobin and therefore less molecular oxygen saturation, a result of anemia. Oxygen content relates to the ability of the subject to adjust to physiologic stress.
The driving force in the oxygen transport system is the heart and resultant cardiac output (CO). The cardiac output is typically about 5.0 liters per minute, with maximums up to about 15.0 liters per minute during exercise. However, cardiac output can drastically fall to about 1.0 or 2.0 liters per minute in states of heart failure. In normal hemostasis with normal hemoglobin cardiac output, and adequate oxygenation there should be sufficient oxygen content in the blood and this content will be transported to peripheral tissues for consumption. Provided below are some equations relating to the oxygen transport system.
Equations of the Oxygen Transport System1.Oxygen Saturation (%)       SO    2    =                    HBO        2                    Hb        +                  HBO          2                      ×    100   Arterial (SAO2) 91%–97%Venous (SVO2) 60%–75%2.Oxygen Content (CO2) (mL O2/100 mL blood = vol %) arterial(2% O2, dissolve) + (98%/O2 Hb saturated)ArterialCAO2 = (PO2 × 0.0031) + (Hb × 1.38 × SAO2)CAO2 = (100 torr × 0.0031) + (15 g × 1.38 × .97)CAO2 = .3 + 20.1CAO2 = 20.4 vol. %VenousCVO2 = (PVO2 × 0.0031) + (Hb × 1.38 × SVO2)CVO2 = (40 torr × 0.0031) + (15 g × 1.38 × .75)CVO2 = .12 + 15.52CVO2 = 15.64 vol. %3.Oxygen Transport (O2T) (mL O2 /min)Arterial: O2TA = CO × CAO2 × 10Venous: O2 TV = CVO2 × 104.Oxygen Consumption (VO2) (mL O2/min)VO2 = CO × Hb × 1.38 (SAO2 − SVO2) × 10VO2 = 5 L/min × 15 g × 1.38 (.97 − .75) × 10VO2 = 228 mL/min5.Cardiac Output (L/min)   CO  =            VO      2                      CAO        2            -              CVO        2

System for monitoring pilot and/or passenger oxygen saturation levels and estimating oxygen usage requirements


Bioresorbable stents for treating airway disorders and methods of treatment of the airway disorders using the bioresorbable stents are disclosed. Once implanted, the stents stabilize or maintain an airway lumen. The radial strength of the stents decreases with time which allows the airway to adjust from being artificially supported to a healed state without artificial support. The stent may be removed from the airway through bioresorption without intervention. The bioresorbable stents include a bioresorbable body having a shape that conforms or is conformable to the shape of the of airway lumen.

Field of the Invention
This invention relates to bioresorbable implantable medical devices and methods of using such devices to stabilize or maintain an airway lumen during treatment of airway disorders.
Description of the State of the Art
This invention relates generally to treatment of laryngeal and tracheal stenosis with endoprostheses that are adapted to be implanted in the airway of an adult or child to stabilize or maintain the airway lumen. An "endoprosthesis" corresponds to an artificial device that is placed inside the body. "Stenosis" refers to a narrowing or constriction of a bodily passage or orifice. The endoprosthesis may stabilize or maintain the airway to facilitate restoring the airway lumen to a healthy or normal state and function. Laryngotracheal stenosis that is treatable by stenting has multiple causes. The most common factors for LTS are prolonged intubation usually associated with general anesthesia, external fracture of laryngeal, cricoid or tracheal cartilage structure, or subglottic stenosis. After surgical laryngeal reconstruction, a laryngotracheal stent is placed to stabilize the airway while it heals. The stent is temporary and the duration of stenting may be short on the order of 4-6 weeks, or longer than 2 months. The stent is not removed until the airway has sufficiently stabilized as premature removal can lead to airway collapse with resulting stenosis. Stabilizing an airway may correspond to permitting continuous unobstructed passage of air to the lungs. Airway disorders of various origins are treated with stents to stabilize or maintain the airway lumen. Stents, generally, are devices that hold open and sometimes expand a segment of an anatomical lumen such as an airway lumen, blood vessel, urinary tract, and bile ducts. A "lumen" refers to a cavity of a tubular structure. In addition to the conditions discussed below, any time the airway is opened to treat a disorder of the larynx, a stent can be considered for stabilization, scar prevention, or airway protection while the region heals.
Laryngotracheal stents, inserted after laryngotracheal reconstruction (LTR) to treat laryngotracheal stenosis, are most commonly used in children and young adults aged less than 20 years. Laryngotracheal stents are used in adults, primarily in the trachea, to relieve obstruction secondary to benign or malignant neoplasms.
Laryngotracheal stents are often used to keep the airway expanded after surgical reconstruction or trauma. Occasionally, laryngeal stents can be used for expansion of a diseased airway. Stenting in the tracheobronchial tree is usually used as a last resort for severe conditions such as recurrent carcinoma and severe tracheal collapse that results in periods of prolonged apnea.
The most common indication for laryngeal stenting follows reconstruction of laryngotracheal stenosis (LTS). Laryngeal stents can be used to keep the laryngeal lumen open and the reconstruction supported and stable. Occasionally, laryngeal stents are used following trauma to the larynx resulting in laryngeal fracture or injury. Stenting may help maintain lumen patency and prevent mucosal lacerations from forming obstructive scar tissue.
The first reason to use stents in cases of LTS is to support the larynx, after a reconstructive technique, often with some form of autologous cartilage, has been performed. A stent can be used to stabilize the cricoid plate once it has been divided anteriorly or posteriorly, with or without cartilage placement, to keep the complex in an expanded formation during healing. Stenting to help stabilize the laryngeal structure normally lasts for 2-6 weeks. It has been shown that when a cartilage graft is inserted, the minimum time necessary for a posterior cricoid split to heal in a distracted manner is 2 weeks. If stenting is performed for a shorter duration, the graft may prolapse into the lumen. For anterior graft placement only, stenting commonly lasts for a week or less.
The second reason for stent placement in LTS repair is to counteract scar contraction. Theoretically, this requires stenting for up to a 6-month period. In general, guidelines to determine the duration of stenting depend on the consistency of the stenosis, the anatomical distortion of the disease process, and the stability of the reconstructive areas.
Tracheal stenting may be used in the treatment of tracheal lesions, tracheomalacia, bronchomalacia, or stenosis that occurs following the resection of lesions.
The purpose of stenting for tracheal lesions varies from palliation, to cure, to stabilization while a reconstructive effort heals. Hence, the laryngotracheal stent primarily has a mechanical role. Use of the stent for delivery of a therapeutic agent is possible and useful agents to release would be antimicrobial agents to combat infection, antiproliferative agents to reduce obstructive scarring, and agents to promote healing. In adults, primary cancer of the tracheobronchial tree or cancer from the head, neck, or chest that extends into the tracheobronchial tree frequently causes lumen compromise and airway obstruction. The intraluminal component can be removed with laser treatment, mechanical debulking, electrocautery, brachytherapy, photodynamic therapy, or cryotherapy. A stent can then be placed to maintain the airway lumen following debridement to counteract collapse or edema. Alternatively, stents can be placed that help compress any lesion extending into the trachea or bronchi, without the need for debulking.
Stents have been used successfully to palliate patients with inoperable bronchogenic cancer, primary tracheal tumors, and metastatic malignancies. Placing a stent in a patient with a terminal illness allows that patient to breathe comfortably and prevents death from asphyxiation.
Tracheomalacia and bronchomalacia (sometimes called tracheobronchomalacia) may be primary or secondary in nature. These conditions usually occur in children, but they can be observed in adults. Tracheomalacia and bronchomalacia are termed primary if they arise from primary cartilage abnormalities of the trachea, such as immature formation of the cartilaginous rings in neonates or relapsing polychondritis in children and adults. Primary tracheomalacia is often observed with a tracheoesophageal fistula. Secondary tracheomalacia or bronchomalacia is caused by extrinsic compression from a structure in the mediastinum.
If tracheomalacia or stenosis occurs following the resection of lesions, stents can be placed in the trachea to prevent scarring or to provide support for the operated segment while it heals. In most situations, surgical correction as primary treatment for a disease process is preferred to stenting alone because complications are decreased. However, situations arise in which patients cannot undergo formal corrective surgery, and stent placement is the only way to prevent a severe apneic event or death.
Current laryngotracheal stents are durable devices, made of silicone, poly(tetrafluoroethylene) (PTFE, Teflon), or other polymers. These devices are removed after implant times ranging from 4 weeks to several months. FIGS. 1A-C depict commonly used devices, including the Montgomery stent, Montgomery T-tube and Aboulker stent, respectively.
If the stenosis is confined to the larynx (i.e., glottis, subglottis), stenting can be short- or long-term. Short-term stenting may be defined as stenting for less than 6 weeks. Long-term stenting is defined as stenting for more than 6 weeks.
Short term stenting for 6 weeks or less may be used because granulation tissue forms at the lower end of the stent above the tracheotomy, potentially leading to tracheal stenosis or collapse above the tracheotomy site. Short-term stenting may also be used for stabilization of cartilage grafts following LTR and/or for separation of mucosal surfaces during healing following laryngeal trauma, repair of web formation or atresia, or excision of a laryngeal lesion. Stents for these indications include Aboulker stents, silicone stents, Montgomery laryngeal stents, endotracheal tubes, and laryngeal keels.
In FIG. 1C, the representative (non-inclusive) samples demonstrate various sizes of Aboulker stents, ranging from 15 mm in diameter at the top to 3 mm in diameter at the bottom. These stents are hollow and are coated with PTFE.
The Montgomery Laryngeal Stent is a molded silicone prosthesis designed to conform to the normal endolaryngeal surface and is constructed of radiopaque implant grade silicone that is firm enough to support the endolarynx postoperatively, yet is soft and flexible enough to ensure a conforming fit while minimizing injury to soft tissues.
The Montgomery T-Tube is designed to maintain an adequate airway as well as to provide support in the stenotic trachea that has been reconstituted or reconstructed.
Use of durable stents usually requires removal of the stent after allowing a period of time for healing to take place. These devices have several complications including migration, fracture, keloid formation, granulation formation, and infection.
Inspection of FIGS. 1A-C reveals they are simple devices that are not expanded in place, are not fenestrated and have various levels of flexibility and compliance. As can be seen in FIG. 1AC, these devices come in a variety of sizes to match different anatomies and this is particularly driven by pediatric use. These devices are all inserted at the as-fabricated or final diameters and are not expanded once inserted in an airway.
Another challenge with these durable stents is selecting how long to keep them in place. LTR requires anterior and/or posterior cricoid splits, sometimes combined with cartilage tissue grafts. After the procedure, the stent is put into place to hold open the airway while healing occurs. The stent can also increase the stability of a graft and prevent scar contracture. Premature removal of the stent can lead to LTR failure.

Bioresorbable laryngotracheal stent and methods of treatment


Apparatus and methods for measuring current flowing through a conductor include a device comprised of a magnetically conductive loop having a plurality of strands and a magnetic field sensor. Each strand has a magnetically conductive material. The strands are configured to pass a magnetic field to a first magnetic field sensor that is positioned adjacent to an end of the first plurality of strands. The plurality of strands may be arranged in various patterns that allow the magnetically conductive loop to be more bendable or flexible than a current-clamp device.

Typical non-contact current sensors capable of measuring direct current (DC) utilize clamp-type or jaw-type sensors having a rigid clamp positionable around an electrical component for measurement. A motor opens and closes the jaws of the clamp and aligns the jaws. Valid measurements require accurate jaw alignment.
Opening the jaws requires a large physical space. In addition, locating a clamp sensor around an electrical component in an electrical panel or other tight space can be awkward or cumbersome for a technician and may cause damage to the electrical component being measured or to nearby components. Vibrations from nearby heavy machinery may exacerbate these problems. Clamp sensors are typically heavier than a standard measurement tool because the jaws include large pieces of iron and a motor for opening, closing, and aligning the jaws.
Rogowski coils are current sensors that are lighter and more flexible than clamp-type current sensors. Rogowski coils are easier to use in tight spaces than most clamp sensors; however, Rogowski coils are not suitable for measuring DC current. A device capable of measuring DC and having a lighter weight and less rigid form factor than a clamp-type meter is desired.


A process is disclosed for rendering shaped aramid and polybenzimidazole articles water repellent by grafting fluorinated compounds to the surface of the articles. The resulting grafted polymer and shaped articles made from the grafted polymer are also disclosed.

1. Field of the Invention
This invention relates to polymer and shaped aramid and polybenzimidazole articles which exhibit an inherent water repellency and to a process for making such inherently water repellent aramid and polybenzimidazole articles. The articles include fibers; and the process for increasing the water repellency of the articles includes a reaction wherein fluoroalkyl groups are grafted onto the surface of the polymer.
2. Description of the Prior Art
Japanese Publication (Kokai) No. 62-81426, published Apr. 14, 1987 on the application of Asahi, discloses a process for treating aramid surfaces to render them more hydrophobic and decrease the coefficient of moisture absorption. The process includes: contact of the aramid surface by alkali metal hydrocarbyls or alkaline earth metal hydrocarbyls in no solvent or in a solvent specifically required to be less polar than dimethyl sulfoxide; and then contact of the metallated aramid by a halogenated aliphatic compound in no solvent or in a solvent specifically required to be less polar than dimethyl sulfoxide. There is no mention of the use of fluoroalkyl-containing alkylating agents.
Japanese Patent No. Sho 62-91542, published Apr. 27, 1987 on the application of Asahi, discloses a process for treating aramid surfaces to render them more hydrophilic and increase the coefficient of moisture absorption. The process includes: contact of the aramid surface by alkali metal-containing or alkaline earth metal-containing compounds in a solvent specifically required to be at least as polar as dimethyl sulfoxide; and then, reacting the aramid surface with water or other polar compound.
Japanese Publication (Kokai) No. 62-110,968, published May 22, 1987, discloses grafting materials to aramid fibers, through the use of epoxide-functional grafting agents, to create a surface with reactive epoxide groups.


A method of determining a location of a mobile device in a system having a plurality of fixed transmitters includes: obtaining, at the mobile device, inference model data defining a plurality of node operations; collecting, at the mobile device, respective proximity indicators corresponding to a subset of the fixed transmitters, each proximity indicator representing a proximity of the mobile device to the respective fixed transmitter; at the mobile device, generating a location according to the proximity indicators and the node operations; and presenting the location.

Mobile computing devices, such as a smart phones, handheld barcode scanners, mobile radio frequency identification (RFID) readers, mobile label printers, and the like, operate in a variety of environments. Such environments can include facilities such as warehouses, retail stores, and the like, in which locationing systems such as the global positioning system (GPS) may not be available. Determining the location of mobile devices in such environments typically requires the deployment of navigational aids within the environment, and also of a host computing device (e.g. a server). The mobile devices may then be configured to gather data from the navigational aids and provide the data to the server, which determines an estimated location of the mobile device based on the above-mentioned data and previously known locations of the navigational aids. Locationing as described above is therefore costly (e.g. due to infrastructural requirements), and may also suffer from reduced accuracy due to multipath RF propagation and noisy measurements.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.
The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.

System and method for mobile device locationing


Provided are an apparatus for synthesizing carbon nanotubes, the apparatus including a reaction tube that provides a space for carbon nanotubes and is formed vertically long, a heating unit that is formed at the outer side of the reaction tube, and heats the reaction tube, a gas-supply unit that sprays reaction gas for synthesizing the carbon nanotubes by reacting with catalysts positioned inside the reaction tube, an exhaustion unit that is connected to the upper portion of the reaction tube, and discharges non-reacted reaction gas for synthesizing the carbon nanotubes, and a blocking unit that is formed inside the reaction tube, discharges only the non-reacted reaction gas for synthesizing the carbon nanotubes to the exhaustion unit, and blocks the discharge of the carbon nanotubes and catalysts, in which the cross-section of the blocking unit is divided in a plurality of polygon structures, and downward-slanted blocking wings are formed at each divided cell.

1. Field of the Invention
The present invention relates to an apparatus for synthesizing carbon nanotubes, and more particularly, to an apparatus for synthesizing carbon nanotubes, which discharges non-reacted gas for synthesizing carbon nanotubes to an exhaustion unit, and includes a blocking unit that blocks the discharge of synthesized carbon nanotubes and catalysts.
2. Description of the Related Art
Carbon nanotubes (CNT) is a carbon allotrope consisting of carbons existing on earth. One atom of carbon is coupled with another atom of carbon in a honeycomb pattern to form a tube shape, and the diameter of the tube is only a few nanometers. The carbon nanotubes (CNT) has good mechanical features, outstanding field-emitting features and highly-efficient hydrogen storage medium features, and is known as a promising new material.
Such carbon nanotubes can be manufactured by an advanced synthesizing technology, and some examples of the technology are the arc-discharge, laser vaporization, plasma enhanced chemical vapor deposition (PECVD), thermal chemical vapor deposition, electrolysis, and flame synthesis.
Generally, the process of manufacturing carbon nanotubes can be divided into the process of applying catalysts on a board where carbon nanotubes are synthesized, the process of synthesizing carbon nanotubes by inserting the board, where the catalysts have been applied, into a reaction tube and making the reaction gas react to the applied catalysts, and the process of returning carbon nanotubes that have been synthesized on the board.
The apparatus for synthesizing carbon nanotubes can be divided into a horizontal type and a vertical type depending on the form in which the reaction tube has been disposed. The apparatus for synthesizing carbon nanotubes with a vertical-type reaction tube is under active development due to the advantages of the size of the reaction tube, the consumption of reaction gas, and efficiency.
Further, the types of carbon nanotubes are divided into single-walled nanotubes (SWNT) and multi-walled nanotubes (MWNT) depending on the number of combinations that form the wall for forming the tube, and especially a bundle type where single-walled nanotubes are combined is called a robe nanotubes. The type of such carbon nanotubes can be determined according to the form of the catalyst reacting to reaction gas, i.e., the shape of the catalysts density, and the particle size, and the types of the used catalyst can be determined according to the method of producing the catalyst.
In a vertical-type carbon nanotubes synthesizer, the catalyst is positioned inside the reaction tube, and by spraying the reaction gas to the catalyst, the catalyst floats inside the reaction tube by the spraying pressure and the synthesis is done. Here, an exhaustion unit that discharges the remaining reaction gas and the remaining gas is positioned on the upper side of the reaction tube, and a blocking unit is formed so that only the reaction gas is discharged through the exhaustion unit, and the synthesized carbon nanotubes and the catalyst are not exhausted.
Here, there is a need for providing a blocking unit that effectively discharges the reaction gas to the outside, prevents the synthesized carbon nanotubes and the catalyst from being discharged, and prevents the carbon nanotubes and the catalyst from being piled up. It is because the productivity can be improved as the synthesized carbon nanotubes and the catalyst, which have not been discharged to the outside by the blocking unit, are synthesized inside the reaction tube again.

Apparatus for synthesizing carbon nanotubes


An automatic test system includes a mechanical frame, a test device mounted to the mechanical frame for testing the electrical performance and the mechanical performance of the connector, a packing device mounted to the mechanical frame for packing the connector which is completed to be tested, a transmission device mounted to the mechanical frame for transmitting the connector to each workstation of the test device and the packing device, a moving device mounted to the mechanical frame for moving the connector to each workstation of the test device and the packing device corresponding to the transmission device, and a control system electrically connected with and controlling the test device, the packing device, the transmission device and the moving device for completing the transmission, test and packing action of the connector.

1. Field of the Invention
The present invention generally relates to a test system, and more particularly to an automatic test system.
2. The Related Art
As is known to all, connectors are widely used in a variety of electronic products, such as cell phones, MP3, MP4, notebooks and so on. With electronic products being developed towards a high precision direction, the connectors are required to develop towards the high precision and miniaturized direction. So, after the connectors are completed being manufactured, the connectors are needed to proceed a series of corresponding mechanical performance test of the connector. Currently, the connectors are respectively placed on each test workstation one by one in manual to proceed the corresponding mechanical performance test. In order to save test time and human power, a conventional automatic test system is invented and applied to proceed the mechanical performance test of the connector.
However, with the development of the technology, a photoelectric sensor is assembled to the connector, so the corresponding automatic test system should have the mechanical performance test function and the electrical performance test function. The above-mentioned automatic test system of the connector just has the mechanical performance test function, and the connector is tested in the manual test way that results in a human cost and a test time waste. And it's apt to make operators generate a fatigue feeling to affect the test stability of the connector on account of the connector being tested in the manual test way, so that a quality of the connector is lowered. Furthermore, the connector is tested by virtue of the conventional automatic test system, though the human cost and the test time waste are saved, and the test stability of the connector is strengthened, the conventional automatic test system is just able to proceed the single performance test of the connector that dissatisfies the test requirement.


Communicating in a peer-to-peer computer environment. A request is received from a user device at a peer provider node computer system, wherein the request is signed by a private key. Provided a public key verifies the private key, providing potential peers to the user device from the peer provider node computer system such that the user device is enabled to utilize the peer-to-peer computer environment for a communication according to user requirements.

Modern technology provides for a variety of communication means and methods. For example, there are many types of communications including voice calls, video calls, text messages, photo messages, etc. Additionally, communication may be one-to-one or multi-party communications. Typically multi-party communications are accomplished by a plurality of devices communicating with a central infrastructure. For example, a central infrastructure may be a central computer server or a group of computer servers maintained in a server farm. A central infrastructure may be expensive to establish, maintain and operate.
The drawings referred to in this description of embodiments should be understood as not being drawn to scale except if specifically noted.

This patent is subject to a terminal disclaimer.


A motorized multi-function tool including a handle assembly, a cover assembly, a rod assembly and an interchangeable tool assembly is disclosed. The handle assembly includes a handle that allows a user to operate the motorized multi-function tool. Within the handle is a battery to power a motor located in the cover assembly. The handle assembly and the cover assembly have the rod assembly therebetween connecting them to one another. The rod assembly includes a shaft which allows the user to set the motorized multi-function tool at different lengths to accomplish distinct tasks. Importantly, the cover assembly has the interchange tool assembly which allow for changing of tool heads for different functions to accomplish different tasks. The different tool heads may be used for manual labor work or for health and beauty purposes as well.

1. Field of the Invention
The present invention relates to a motorized multi-function tool and, more particularly, to a motorized multi-function tool having interchangeable heads to permit completing of various tasks with one same tool.
2. Description of the Related Art
Several designs for motorized multi-function tools have been designed in the past. None of them, however, include an interchangeable cover assembly having a head that includes a motor therein. The heads are capable of achieving various tasks such as cutting or suctioning, for example. This allows a user to use one same tool to complete various necessary tasks at home or in a work environment. Further, there is a quick and easy change of heads for efficiency when working on various tasks.
Applicant believes that a related reference corresponds to U.S. Pat. No. 4,237,610 for a Portable, Electrically Energized, Cordless Grass Trimmer. Applicant believes another related reference corresponds to U.S. Pat. No. 4,089,114 for a Cutting Device. None of these references, however, teach of interchangeable heads for accomplishing various tasks such as cutting or suctioning with one same tool.
Other documents describing the closest subject matter provide for a number of more or less complicated features that fail to solve the problem in an efficient and economical way. None of these patents suggest the novel features of the present invention.


An apparatus for rubbing an alignment layer by which a defective rubbing due to a load can be prevented by installing a head at an upper portion of a frame, the apparatus including a frame, a rubbing table to which a substrate having an alignment layer is loaded, a rubbing roll disposed at an upper portion of the rubbing table inside the frame, and a head disposed at an upper portion of the frame that supports the rubbing roll.

1. Field of the Invention
The present invention relates to an apparatus for rubbing an alignment layer, and particularly, to an apparatus for rubbing an alignment layer of a Liquid Crystal Display (LCD) device that is capable of uniformly rubbing an alignment layer by minimizing an affect due to a force of a rubbing roll that has an increased size and weight.
2. Discussion of Related Art
As various portable electric devices such as mobile phones, personal digital assistants (PDA), notebook computers, etc., continue to be developed, various types of flat panel display devices such as liquid crystal displays (LCDs), plasma display panels (PDPs), field emission displays (FEDs), and vacuum florescent displays (VFDs), having a compact construction, light weight, and low power-consumption also continue to be developed. Due to the ease with which they are driven and to their superior ability to display images, LCDs are extensively used in these electric devices.
The LCD device is a transmissive type display device for displaying images by adjusting an amount of light transmitted through a liquid crystal layer according to an alignment direction of liquid crystal molecules. Hence, an alignment process must be performed for the LCD device to provide each liquid crystal molecule with a uniform direction. In general, many methods are known to produce an alignment layer. An alignment method using a rubbing operation is currently used most frequently. The rubbing alignment method first forms an alignment layer on a substrate and then rubs the alignment layer by use of a rubbing cloth to form uniform microgrooves on a surface of the alignment layer. The alignment layer having the microgrooves on its surface provides each liquid crystal molecule with an alignment controlling force, thereby constantly aligning the liquid crystal molecules over the entire surface of the alignment layer in a desired direction.
However, the alignment method using rubbing may cause the following problems. The rubbing process may include a rubbing cloth that is wound on a rubbing roll and then is placed in contact with the rubbing roll while the rubbing roll is rotated and moved in one direction. Meanwhile, the LCD device is being employed in electric devices such as TV sets as well as portable electric devices recently and accordingly, the size of the LCD device is greatly increasing (furthermore, the mother substrate for fabricating LCD panels is much greater in size) that results in an increase of the width and weight of the rubbing roll used to perform the alignment process for a large LCD device.
In the meantime, the alignment controlling force or a surface fixing force of the alignment layer that is rubbed by the rubbing roll is determined by the microgrooves formed in the alignment layer, and the depth of the microgroove is different based upon a pressure of the rubbing roll applied to the alignment layer. However, as the width and weight of the rubbing roll increases, it is difficult to uniformly maintain the pressure applied to the mother substrate, that results in the fabrication of a defective LCD device by defectively rubbing the alignment layer.


The invention relates to a method for enhancing a surfactant, in particular a pulmonary surfactant, as well as a method for producing a surfactant enhancement agent, in particular a pulmonary surfactant enhancement agent. The invention also relates to a surfactant enhancement agent and a use of an enhancement agent for enhancing a surfactant, in particular, a pulmonary surfactant. Further, the invention relates to a method of mitigating oxidative damage to pulmonary surfactant by adding a cholesterol-sequestrating agent such as cyclodextrin. Finally, a method is provided for treating a patient having surfactant dysfunction due to oxidative damage to pulmonary surfactant by administering a surfactant-protective amount of a cholesterol-sequestrating agent to protect the surfactant from the negative effects of oxidative degradation. In the examples we show that MβCD, a cholesterol-sequestrating agent, can restore dysfunctional surfactant removed from the lungs of children with cystic fibrosis and non CF bronchiolitis to normal function.

It is known that the pulmonary surfactant is a surface-active substance lining the respiratory system of the lung. Type II pneumocytes produce the surfactant, store it as lamellar bodies and finally express it in the alveolar liquid phase. From there it spreads as a molecular thin film on the air/water boundary surface. It displays its effect by dynamically adapting the surface tension of the boundary surface to the current extension of the boundary surface during the breathing cycle.
Pulmonary surfactant prevents alveolar collapse and flooding at end-expiration, affords patency of small airways and reduces the work required for breathing. Pulmonary surfactant consists of 80-90% (by weight) phospholipids, with a large proportion (−30-45%) being disaturated dipalmitoylphosphatidylcholine (DPPC). The surfactant also contains 50-60% unsaturated phospholipids with reported levels of polyunsaturated species >10% of total phospholipids. Surfactant also contains four surfactant-associated proteins—SP-A, B, C, and D. A highly surface-active form of pulmonary surfactant, referred to as the large aggregate fraction, is enriched in the hydrophobic proteins SP-B and SP-C. Neutral lipids, primarily cholesterol, make up the remaining 2-10% of surfactant.
In 1959 it was shown that the lack of pulmonary surfactant in the lungs of premature infants leads to respiratory distress syndrome (RDS), which at that time was the most frequent cause of death for premature infants. For about the past 15 years, extracts from the lungs of cattle or pigs have been used as a medication to treat RDS. Animal preparations are generally expensive and carry the risk of transmitting infectious diseases.
The surfactant (short for surface active agent) consists of glycero-phospholipids, specific proteins, neutral fats and cholesterol. The surfactant covers the alveolar surface and reduces the surface tension, so that after birth the alveoli do not collapse in the human body during exhalation.
Insufficient function of the surfactant can be the cause of respiratory insufficiency, known as Infant Respiratory Distress Syndrome (IRDS) in premature infants and newborns or in adults as Adult Respiratory Distress Syndrome (ARDS). These lung illnesses are the result of a surfactant deficiency, which lead to an inadequate expansion of the lungs (atelectasis) after a collapse of the pulmonary alveoli.
The lung surfactant consists of 90% lipids and 10% proteins. Although cooperation between the surfactant-specific proteins and the lipids is necessary for a completely functional respiratory process, the lipids are essential for the vitally important reduction of surface tension.
The function of pulmonary surfactants and their inhibited function with pulmonary infections and pulmonary diseases have been described in numerous publications. In this regard reference is made to the publications:
T. R. Martin, Cytokines and the Acute Respiratory Distress Syndrome (ARDS): a question of balance, Nat. Med. 3 (1997), pp. 272.
Artigas, G. R. Bernard, J. Cadet, D. Dreyfuss, L. Gattinoni, The American-European consensus conference on ARDS, part 2: ventilatory, pharmacologic, supportive therapy, study design strategies, and issues related to recovery and remodeling. Acute respiratory distress syndrome, Am. J. Respir. Crit. Care Med. 157 (Pt 1) (1998), pp. 1332.
G. R. Bernard, A. Artigas, K. L. Brigham, J. Carlet, K. Falke, The American-European consensus conference on ARDS: definitions, mechanisms, relevant outcomes, and clinical trial coordination, Am. J. Respir. Crit. Care Med. 149 (1994), pp. 818.
A. B. Montgomery, M. A. Stager, C. J. Carrico, E. D. Hudson, Causes of mortality in patients with the adult respiratory distress syndrome, Am. Rev. Respir. Dis. 132 (1985), pp. 485.
G. Karagiorga, G. Nakos, E. Galiatsou, M. E. Lekka, Biochemical parameters of bronchoalveolar lavage fluid in fat embolism, Intensive Care Medicine 32 (2006), pp. 116-123.
L. D. Hudson, K. P. Steinberg, Epidemiology of acute lung injury and ARDS, Chest 116 (1999), pp. 74S.
G. Devendra, R. G. Spragg, Lung surfactant in subacute pulmonary disease, Respir. Res. 3 (2002), pp. 19.
M. Griese, R. Essl, R. Schmidt, E. Rietschel, F. Ratjen, M. Ballmann, K. Paul, Pulmonary surfactant, lung function, and endobronchial inflammation in cystic fibrosis, American Journal Of Respiratory And Critical Care Medicine 170 (2004), pp. 1000-1005.
M. Griese, L. Felber, K. Reiter, R. Strong, K. Reid, B. H. Belohradsky, G. Jager, T. Nicolai, Airway inflammation in children with tracheostomy, Pediatr. Pulmonol. 37 (2004), pp. 356-361
Bachofen H & Schürch S (2001) Alveolar surface forces and lung architecture. Comparative Biochemistry and Physiology—Part A: Molecular & Integrative Physiology 129: 183-193.
Clements J (1962) Surface phenomena in relation to pulmonary function. Physiologist 5: 11.
Yu S, Harding P G, Smith N & Possmayer F (1983) Bovine pulmonary surfactant: Chemical composition and physical properties. Lipids 18: 522-9.
Veldhuizen R, Nag K, Orgeig S & Possmayer F (1998) The role of lipids in pulmonary surfactant. Biochimica Et Biophysica Acta (BBA)—Molecular Basis of Disease 1408: 90-108.
Yu S, Harding P G R, Smith N & Possmayer F (1983) Bovine pulmonary surfactant: Chemical composition and physical properties. Lipids 18: 522-529.
Postle A D, Heeley E L & Wilton D C (2001) A comparison of the molecular species compositions of mammalian lung surfactant phospholipids. Comparative Biochemistry and Physiology—Part A: Molecular & Integrative Physiology 129: 65-73.
Possmayer F, Nag K, Rodriguez K, Qanbar R & Schurch S (2001) Surface activity in vitro: Role of surfactant proteins. Comp Biochem Physiol A Mol Integr Physiol 129: 209-20.
Pulmonary surfactants form a complex film, which has or plays a critical role in the reduction of surface tension in the respiratory tract in the hydrated air/lung interface. With inflammatory lung diseases, the molecular profile of pulmonary surfactants in the alveoli and respiratory tract is changed so that the pulmonary surfactant film is quite a lot less effective or ineffective for reducing the surface tension, which is accompanied by a strong decrease in the area available for gas exchange.
Furthermore, it is known that an elevated level of cholesterol in the surfactants is a major cause of surfactant dysfunction. In this regard reference is also made to the following publication:
L. Gunasekara, S. Schurch, W. M. Schoel, K. Nag, Z. Leonenko, M. Haufs, M. Amiein, Pulmonary surfactant function is abolished by an elevated proportion of cholesterol, Biochimica Et Biophysica Acta 1737 (2005), 27-35.
Furthermore, it has been shown that the release of reactive oxygen species (ROS) from activated leukocytes or following exposure to environmental pollutants may result in a highly oxidizing milieu within the lungs. Increased levels of reactive oxygen species and their byproducts have been detected from bronchoalveolar lavage fluid collected from patients with ARDS, asthma, CF, ventilator induced lung injury (VILI) or chronic obstructive pulmonary disease (COPD), among many other disease states. Several studies have shown that oxidation of various pulmonary surfactants greatly impairs in vitro and in vivo function, which has so far been largely attributed to oxidative alterations of susceptible residues in SP-B and SP-C, whereas peroxidation and hydrolysis of phospholipids were considered less important. In this regard reference is also made to the following publications:
K. Rodriguez-Capote, D. Manzanares, T. Haines, F. Possmayer, Reactive oxygen species inactivation of surfactant involves structural and functional alterations to surfactant proteins SP-B and SP-C, Biophysical Journal 90 (2006), 2808.
S. Andersson, A. Kheiter, T. A. Merritt, Oxidative inactivation of surfactants, Lung 177 (1999), 179.
L. Mark, E. P. Ingenito, Surfactant function and composition after free radical exposure generated by transition metals, Am. J. Physiol.—lung Cell. Mol. Physiol. 276 (1999), L491.
N. Gilliard, G. P. Heldt, J. Loredo, H. Gasser, H. Redl, T. A. Merritt, R. G. Spragg, Exposure of the hydrophobic components of porcine lung surfactant to oxidant stress alters surface tension properties, Journal Of Clinical Investigation 93 (1994), 2608.
Lang J D, McArdle P J, O'Reilly P J & Matalon S (2002) Oxidant-antioxidant balance in acute lung injury*. Chest 122: 314S-320S.
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Lamb N J, Gutteridge J, Baker C, Evans T W & Quinlan G J (1999) Oxidative damage to proteins of bronchoalveolar lavage fluid in patients with acute respiratory distress syndrome: Evidence for neutrophil-mediated hydroxylation, nitration, and chlorination. Crit. Care Med 27: 1738.
Andersson S, Kheiter A & Merritt T (1999) Oxidative inactivation of surfactants. Lung 177: 179-189.
Bailey T C, et al (2006) Physiological effects of oxidized exogenous surfactant in vivo: Effects of high tidal volume and surfactant protein A. American Journal of Physiology—Lung Cellular and Molecular Physiology 291: L703-L709.
Gilliard N, et al (1994) Exposure of the hydrophobic components of porcine lung surfactant to oxidant stress alters surface tension properties. J Clin Invest 93: 2608.
Haddad I Y, et al (1993) Mechanisms of peroxynitrite-induced injury to pulmonary surfactants. American Journal of Physiology—Lung Cellular and Molecular Physiology 265: L555-L564.
Mark L & Ingenito E (1999) Surfactant function and composition after free radical exposure generated by transition metals. American Journal of Physiology—Lung Cellular and Molecular Physiology 276: L491-L500.
Stenger P C, et al (2009) Environmental tobacco smoke effects on lung surfactant film organization. Biochimica Et Biophysica Acta (BBA)—Biomembranes 1788: 358-370.
Rodriguez-Capote K, Manzanares D, Haines T & Possmayer F (2006) Reactive oxygen species inactivation of surfactant involves structural and functional alterations to surfactant proteins SP-B and SP-C. Biophys J 90: 2808-2821.
Manzanares D, et al (2007) Modification of tryptophan and methionine residues is implicated in the oxidative inactivation of surfactant protein B. Biochemistry 46: 5604-5615.
Keating E, et al (2007) Effect of cholesterol on the biophysical and physiological properties of a clinical pulmonary surfactant. Biophys J 93: 1391-1401.
This invention addresses the unaddressed question concerning the contribution of cholesterol to oxidation-induced surfactant dysfunction. In particular, it remained unknown, until this invention; whether oxidative alterations to surfactant interact with normal or increased levels of cholesterol to negatively affect surfactant function.

Method of treating pulmonary surfactant dysfunction or respiratory distress syndrome by administering cyclodextrin or a derivative thereof


A jet pump is provided for supplying fuel from a fuel tank into a sub-tank, which is accommodated in the fuel tank. The jet pump includes a welded portion adapted to being welded to an outer wall surface of a bottom portion of the sub-tank. A swirl portion defines therein a swirl chamber. A jet nozzle generates negative pressure by jetting swirl-flowing fuel passing through the swirl chamber so as to draw fuel from the fuel tank into the sub-tank. A pressure-receiving portion defines a clearance with respect to the swirl portion. The pressure-receiving portion extends from the welded portion in a direction to distant from the sub-tank. The pressure-receiving portion is applied with force toward the welded portion when the welded portion is welded to the sub-tank.

Conventionally, a fuel feed apparatus includes a sub-tank accommodated in a fuel tank. The fuel feed apparatus further includes a jet pump for supplying fuel from the fuel tank into the sub-tank. Specifically, according to US 2004/0074995 A1 (JP-A-2004-156588), a jet pump supplies fuel into the sub-tank, so that the fuel level in the sub-tank can be maintained higher than the fuel level in the fuel tank, even when fuel in the fuel tank decreases. In this structure, the fuel pump accommodated in the sub-tank is capable of steadily pumping fuel from the sub-tank, even the fuel level decreases in the fuel tank.
In US 2004/0074995 A1, a jet pump is welded to the outer wall surface of the bottom portion of the sub-tank. When the jet pump is welded to the sub-tank, the jut pump may be applied with force onto the sub-tank.
Here, a jet pump is capable of generating a swirl flow to jet the swirl-flowing fuel through a jet nozzle. In this jet pump, a swirl chamber is provided in upstream of the jet nozzle for supplying swirl-flowing fuel toward the jet nozzle. In general, a cylindrical member defines the swirl chamber therein.
When the cylindrical member defining the swirl chamber is applied with force toward the sub-tank, it is difficult to steadily applying force onto the round surface of the swirl chamber. Therefore, when application of force to the cylindrical member is unstable, the cylindrical member may be tilted, and misaligned with respect to the sub-tank.
Furthermore, when the cylindrical member defining the swirl chamber is directly applied with force, the cylindrical member may be deformed, and the shape of the swirl chamber cannot be maintained.

Jet pump, fuel feed apparatus having the same, and method for welding the same


A power sharing device is disclosed, having a primary utility in supplying power to automotive block heaters or other auto warming devices at a user selectable duty cycle of 12.5% or 25%. In a first mode, power is supplied to 4 outlets in a sequential manner, for 15 minutes each. In a second mode, power is supplied to the 4 outlets in a sequential manner, for 7.5 minutes each, followed by a period of 7.5 minutes in which power is not supplied. The user may elect to initiate a delay period, that is selectable between 1 and 2 hours, to precede the sequence of power distribution, allowing time for the car to cool before the power cycles begin. A test circuit, activated by a pushbutton, allows a user to distinguish between the periods of time when power is not being supplied to an outlet as a part of the sequential sharing of power between outlets and a circuit malfunction, such as a blown fuse.

It is well-known in northern climates to use automotive block heaters during the winter months. Such heaters maintain the engine block and oil temperatures well above the ambient temperatures. Similar heaters are available for automotive radiators and batteries.
Unfortunately, since such equipment must be manufactured to stand up under the most extreme weather conditions, it is often the case that excessive power is consumed under standard or milder conditions. This is true not only of automotive block, radiator and battery heaters, but also heaters used in animal husbandry, such as those used to prevent the drinking water of livestock from freezing. As a result, money is wasted in operation during all but the most extreme weather conditions.
As a result, power sharing devices have been developed to cycle power to one or more outlets, thereby lessening the duty cycle of an individual heating apparatus from 100% to some fraction thereof. However, due to their construction, most such power cycling devices lack the functionality required to be fully effective in supplying the amount of power required for the efficient operation of the heating device.
A first flaw common to most power sharing and cycling devices it that the power supply commences at the moment the heating devices are plugged in. As a result, electrical power is expended heating a warm engine.
A second flaw common to many power sharing devices is the use of mechanical construction techniques that result in a high parts count and failure rate, component degradation over time and high cost of manufacture.
An additional flaw common to power sharing devices is that when power is in the off portion of the cycle there is no method and supporting circuit that allows the user to determine if the power is simply in the off portion of the cycle, or if there has been a circuit failure.
A still further flaw common to most power sharing devices is that the user has little or no control over the duty cycle of the power distribution.
For the foregoing reasons, there is a need for power sharing device that can, at the user's option, delay the inception of the operation of the heating device. The power sharing device must be able to function in any ambient temperature, and must be extremely reliable. The power sharing device must provide the user with control over the power duty cycle at which the heating devices are operated. Also, the power sharing device must provide the user with circuitry to test all outlets to determine if power is being supplied and to determine if there is a circuit failure.


A fluid loss device has a housing, a seal assembly, a running tool, and a plug. The housing of the fluid loss device is placed in a production string before a well bore is completed. The plug is attached to the running tool, and the running tool is attached to a wash pipe.. The fluid loss device is activated by lifting the wash pipe and the running tool, thereby engaging the plug with the seal assembly, engaging the seal assembly with the housing, and severing the plug from the running tool. Activation of the fluid loss device inhibits fluid communication through the fluid loss device and reduces damage to the well structure behind the fluid loss device while completion operations are performed in other areas of the well bore.. The fluid loss device is deactivated by forcing the plug through the fluid loss device with mechanical force or pressure, or by chemically eroding the diameter of the plug until the plug passes through the fluid loss device. Once the fluid loss device is deactivated, the isolated area of the well bore is reopened for access through the production string.

The present invention relates generally to apparatus for well completions, and in particular, to apparatus for isolating distinct zones from each other in a well bore.
In completion of a well bore for oil, gas, or the like, it is often desired to perform certain completion operations in a particular zone of the well bore, such as gravel packing, acidizing, or the like. After completion of one of these operations, it is often necessary to protect the structure in which the operation was performed by isolating the zone in which the operation was performed from other zones of the well bore during completion operations of the other zones. However, after operations in the other isolation areas of the well bore have been completed, it is necessary to open the isolated area to complete the well bore. Therefore, there is a need for apparatus and methods for isolating a zone of the well bore that can be re-opened for final completion of the well bore.
Completion of the well bore can be affected by the type of debris that is created within that well bore. Therefore, there is a need for apparatus and methods of isolating particular zones in a well bore that reduce the amount of debris that negatively influences the completion of the well bore.
Before a zone is isolated in a well bore, it may be necessary to draw fluids from the zone to be isolated through any device that is later used to isolate the particular zone. Fluid flow through an isolation device, prior to use of the device to isolate a particular zone, may be at high flow rates. Therefore, there is a need for apparatus and methods which allow high fluid flow to and from the zone to be isolated, prior to isolating that particular zone.


In an F-type electrochemical cell 20, in a casing 21, a positive electrode 23 in which carbon dioxide gas is used as a positive electrode active material and a negative electrode 25 are placed so as to face each other with a separator 27 therebetween, and an electrolyte solution 28 is injected between the positive electrode 23 and the negative electrode 25. A tank 30 storing carbon dioxide gas is connected to the positive electrode 23, and carbon dioxide gas is supplied to the positive electrode 23 through a holding member 29. By supplying carbon dioxide gas to the positive electrode in such a manner, the cell can be operated as a battery. Furthermore, when used a primary battery, carbon dioxide can be immobilized in the battery, which is desirable.

1. Field of the Invention
The present invention relates to a gas battery and a method of use of the gas battery.
2. Description of the Related Art
Air batteries are known in which a metal is used as the negative electrode active material, and oxygen in air is used as the positive electrode active material. In such air batteries, since it is not necessary to store oxygen, which is the positive electrode active material, in the battery, it is expected that the capacity of air batteries will increase. As one of such air batteries, for example, a battery having a positive electrode in which a positive electrode of an air battery and a positive electrode of a normal lithium ion secondary battery are combined has been proposed (for example, refer to Japanese Unexamined Patent Application Publication No. 2006-286414). In this air battery, while suppressing degradation of the negative electrode active material by decreasing the amount of air to be supplied, electric power is also supplied by the lithium ion secondary battery as another battery. Therefore, it is considered to be possible to increase the battery capacity.

Gas battery comprising carbon dioxide gas as a positive electrode active material and method of use of gas battery


A collapsible pedal box for an automobile is designed to collapse in the case of a frontal impact of the automobile, to reduce the risk of trapping the driver's feet. One or more pedals (13) are supported on a pivot shaft which is supported at its ends by pivot shaft supports (15,17) locked with respect to the side walls (1,3) of the pedal box that they are prevented from moving outwardly along an axis of the pivot shaft. Relative movement between the pedal box and another structural member within the driver's compartment in the case of a front-end impact causes first the unlocking and then the movement apart of the pivot shaft supports (15,17), and release of the pivot shaft and pedal assembly.

The improved design of safety shell structures around the driving compartment of a motor vehicle, and the improvements in the shock absorbing characteristics of engine compartments have meant that it is now much less likely that the driver of a vehicle in a front-end collision will be killed outright. With that increase in vehicle safety comes another concern, which is that the driver whose life has been spared by good vehicle design should not become injured or trapped in the vehicle by the pedal box structure around the driver's feet.
Brake and clutch pedal boxes have been proposed which collapse on application of an excessive load such as that applied by the forward momentum of a driver when the vehicle is in a front-end collision. A collapse of the pedal box in such a situation permits the pedals of the vehicle to move forward and away from the driver's feet, providing important extra legroom to reduce the risk of the driver's feet becoming trapped in the accident. Even a few centimetres of extra legroom in such circumstances can be a significant safety advantage.
Various prior proposals for collapsible pedal box design have contemplated making the pedal box collapse dependent on the impact itself. It is however important to reduce as much as possible the extent to which the reaction pressure of the driver's foot on the pedal or pedals is necessary to initiate pedal box collapse. Similarly it is important to reduce as much as possible the reliance on any other member which might come into contact with the driver, such as a steering column member, as a source of the reaction pressure.
A collapsible pedal box has previously been described in EP 0827874. The pivot shaft is journalled between pivot shaft supports which are permanently mounted on the inner surface of the opposing side walls. In the event of a frontal impact, a member in the passenger compartment collides with the front of the two side walls forcing them apart while on the engine side the side plates are brought together. Accordingly, the two pivot shaft supports are forced apart to release the pivot shaft. However, since the two side walls twist in opposite directions during the impact, the two pivot shafts are unable to move mutually apart along the axis of the pivot shaft and so there is a greater likelihood that the pivot shaft will still be retained by one of the supports after impact.


A conventional dynamic testing machine, such as an MTS (Material Test System) is modified to allow for a new method for dynamically monitoring fatigue damage in a specimen. Load and stroke signals are used to determine phase angle and gain frequency response parameters for a specimen as it is cyclically loaded. Although the cycles required for specimens to fatigue to failure varies greatly from specimen to specimen, the phase shift between the load and stroke signals as well as the gain of the stroke signal remains fairly constant from specimen to specimen. These characteristic parameters can be used to accurately determine the percent of life remaining and residual strength in other specimens.

1. Field of the Invention
The present invention generally relates to a method for accurately determining the percentage of life remaining in a polymeric or composite material which is undergoing cyclic loading. More particularly, the invention is related to determining rate of damage and total damage of a material by measuring the frequency response of the material.
2. Description of the Prior Art
Polymeric and composite materials are becoming more widely used in engineering applications that have traditionally employed metals. For example, aircraft wings, gears and cams, automobile body parts, space vehicle parts, as well as many other applications now employ polymeric and composite materials. It is generally not possible to reproduce in a laboratory all of the engineering environments in which such components must serve. It is particularly difficult to establish the nature of long-term parameters from laboratory tests that cannot be conducted over the required service life of the component.
Many engineering applications involve applied loads that vary in time. The behavior of materials under these conditions is generally characterized by applying cyclic loading in a "fatigue" test. Various cyclic tensile and compressive amplitudes are generally applied, and the number of cycles required to fail the material under those conditions is recorded. Fatigue damage is evidenced by a decrease in strength and stiffness. In some cases, tests may be terminated after some period of cyclic loading and residual strength determined by breaking the specimen material. The data from such destructive tests are usually characterized by empirical means and generalized by implication or extrapolation to a variety of service conditions for which the materials were not specifically tested in the laboratory.
Additionally, the number of cycles required to fail a material varies widely even among similar samples of like material composition. One specimen may fail after only 100 cycles, while another may last for 1,000,000 cycles. Many specimens are tested to determine a median life; however, for any given sample, this could be a very inaccurate predictor of life.
The static nature of prior art fatigue tests is not desirable since every time the test is stopped, the initial conditions of the forced vibrations are altered. Therefore, in order to fully understand the fatigue behavior of the materials as a function of stiffness change, it is desirable to monitor the dynamic response of the specimen continuously over time.
One prior art method for dynamically monitoring the fatigue of a composite specimen has involved the use of a strain gauge. In this method, a strain gauge is secured to the surface of a sample and the sample is cyclically loaded with the output of the strain gauge being indicative of the stiffness change for the sample. It is assumed that the fatigue measured at the point of attachment for the strain gauge is the same for the rest of the sample. Therefore, as the strain gauge is cyclically loaded, it begins to stretch further and further and this increased stretching is reflected by a change in the electrical output of the strain gauge.
Another prior art method for dynamically monitoring fatigue has involved the use of extensometers. In this method, an extensometer is adhesively attached over a surface area of the sample. As the sample is cyclically loaded, the extensometer outputs electrical signals related to the changes in the surface area of the sample adjacent to the extensometer. Just as in the case of the strain gage, discussed above, it is assumed that these limited area changes are indicative of changes in the sample as a whole. Additionally, because the surface characteristics of the sample will change as it is loaded, it is difficult to keep the extensometer or strain gauge secured to the sample.
Both strain gages and extensometers measure the stiffness of a material. However, a major problem with both the strain gage and extensometer approach to dynamic material fatigue monitoring is that the strain gages and extensometers cannot be used in a corrosive or extreme temperature environment. This is because the heat or corrosive environments will affect or destroy the equipment in addition to affecting the material under test. This limitation prevents testing for certain application areas. For example, when the space shuttle re-enters the earths atmosphere, temperatures in excess of 3000.degree. F. and a multiplicity of highly reactive ions are encountered. Neither stain gages, nor extensometers could be used under such harsh laboratory conditions.
If extensometers or strain gages cannot be used, monitoring stiffness change using classical methods as a measure of damage is not possible. Therefore, an experimental technique other than life estimation based on the median life or on stiffness degradation should be used for analyzing damage evolution and growth mechanisms throughout life.

Dynamic measurement of material strength and life under cyclic loading