An external resonator type variable-wavelength LD light source which can compensate errors of a change in an oscillation wavelength caused by a change in an LD driving current, a change in the oscillation wavelength caused by a change in a temperature of an entire light source unit, a difference between set and actual wavelengths caused by mechanical factors to thereby ensure a wavelength reproducibility of 0.001 nm even when the LD driving current or operational temperature varies. The light source includes a light source unit temperature detection member for detecting a temperature of an entire semiconductor laser light source unit; a storage unit for storing therein oscillation wavelength changes of the semiconductor laser light source unit on the basis of a change in a driving current to the semiconductor laser, of a change in the temperature of the entire semiconductor laser light source unit detected by the light source unit temperature detection member, and of a change in an encoder output value measured by an encoder; and a wavelength change compensation member for compensating a change of the oscillation wavelength of the semiconductor laser light source unit on the basis of the oscillation wavelength changes stored in the storage unit.

1. Field of the Invention
The present invention relates to an external resonator type of a variable-wavelength semiconductor laser light source for use in coherent light communication/measurement technique fields.
2. Description of the Related Art
In coherent light communication/measurement techniques, a semiconductor laser (referred to as the LD, hereinafter) light source of a single mode oscillation type which can change its wavelength in a wide range and have a narrow spectral line width and a good set-wavelength accuracy has been demanded.
In specifications of such a light source, there has been demanded in the market a light source which can have a variable width of 100 nm, a wavelength setting resolution of 0.001 nm and a wave reproducibility of 0.001 nm and also which can be operated with a constant light output.
Such LD light sources of the single mode oscillation type capable of changing the wavelength in a wide rage as mentioned above generally include an LD light source of an external resonator type which uses a diffraction grating.
The operation of oscillation wavelength of an external resonator type of LD light source using a diffraction grating will be explained briefly, as follows.
The oscillation wavelength of the LD light source is given by the following relational equations (1) and (2). The light from the LD light source oscillates with a resonating wavelength .lambda..sub.M which is in the vicinity of the Bragg wavelength .lambda..sub.b leading to a small mirror loss. EQU .lambda..sub.M =2.times.n.times.L/M (1) EQU .lambda..sub.b =2.times.d.times.sin(.theta.)/m (2)
where
.lambda..sub.m is the resonance wavelength in the external resonator, PA1 M is the longitudinal mode (integer) in the external resonator, PA1 L is the length of the external resonator, PA1 n is the refractive index of the external resonator, PA1 .lambda..sub.b is a Bragg wavelength, PA1 d is a spacing between grooves in the diffraction grating (grating constant), PA1 .theta. is an incident angle to the diffraction grating (Littrow mounting), and PA1 m is an order of reflected light of diffraction grating (usually, m=1)
Therefore, in an LD light source using a diffraction grating, the resonance wavelength .lambda..sub.M can be changed by changing the Bragg wavelength .lambda..sub.b to vary M. That is, the wavelength can be changed in a wide range by changing the incident angle .theta. to the diffraction grating with allowing mode hop. In order to change the wavelength successively without causing mode hop, the length of the external resonator L may be changed so that the longitudinal mode M is always constant corresponding to the incident angle .theta. to the diffraction grating. For example, a sine bar mechanism is adopted for this purpose. The principle thereof will be explained briefly with reference to FIG. 9, as follows.
In FIG. 9, an LD 1 and a diffraction grating 2 form a Fabry-Pe.GAMMA.rot resonator. The resonance wavelength .lambda..sub.M thereof in the equation (1) is expressed as follows. ##EQU1## where L.sub.A is the length of an arm (sine bar).
Accordingly, the difference between the wavelengths .lambda..sub.M and .lambda..sub.b is as follows. EQU .lambda..sub.M -.lambda..sub.b =2.times.sin(.theta.).times.{(L.sub.A /M)-(d/m)} (4)
Therefore, when the light source is designed to satisfy a condition (L.sub.A /M)=(d/m), the wavelength shift can be set at zero regardless of the rotational angle 2 of the diffraction grating 2.
Thus, the wavelength can be continuously changed without the mode hop.
FIG. 10 is an exemplary arrangement of a prior art external resonator type variable-wavelength LD light source.
First, an LD unit 4 includes, as shown in FIG. 11, a Fabry-Pe.GAMMA.rot type LD 1 coated on its one end face with an anti-reflection film (referred to as the AR coating, hereinafter) la, lenses 5 and 6, and an optical isolator 7. Further mounted to the LD unit 4 are a temperature detecting element 8 and a Peltier element 9, both of which are controlled with respect to temperature by a temperature adjustment circuit (referred to as the ATC circuit, hereinafter) 10.
In the illustrated example, light going from an end face side of the AR coating la of the LD 1 is changed by the lens 5 to parallel or collimated light. The lens 5 comprises preferably a non-spherical lens or a combined or composite lens having a small liquid-level aberration.
An LD end face 1bnot having the AR coating la applied thereon as well as the diffraction grating 2 as an external reflecting mirror form an external resonator.
The diffraction grating 2 is mounted to a rotary mechanism 11 and to one end of an arm (sine bar) 3, and the arm 3 abuts at the other end against an end face of a parallel moving mechanism 12.
The parallel moving mechanism 12, which has the LD unit 4 fixedly mounted thereto, is arranged to be moved in parallel with directions shown by arrows X. Provided in the vicinity of the parallel moving mechanism 12 is a switch 13 as a position detecting means.
A motor unit 14 as a driver unit includes a motor and an encoder, the motor being driven according to a pulse signal received from a control unit 15.
The aforementioned LD unit 4, diffraction grating 2, rotary mechanism 11, arm 3, parallel moving mechanism 12, switch 13 and motor unit 14 are mounted on an optical system base 16.
The LD 1 is driven by an LD driving current I.sub.LD received from an LD driver circuit 17.
A beam splitter 18 is an optical device which acts to pass therethrough part of output light P.sub.O emitted from a variable-wavelength LD light source unit 19 as output light P.sub.O1 and to reflect part of the remaining output light P.sub.O as output light P.sub.O2. Further, a PD unit 20 receives the reflected light P.sub.O2, converts it to a voltage value V(P.sub.O2), and outputs the voltage value to the LD driver circuit 17.
Since the voltage value V(P.sub.O2) received from the PD unit 20 is fed back to the LD driver circuit 17 to control the LD driving current I.sub.LD, constant light output operation can be realized. When the constant light output operation is not carried out, on the contrary, it is also possible to control the LD driving current I.sub.LD with use of a signal I.sub.SET received from the control unit 15.
Explanation will next be made as to how to set wavelength in FIG. 10.
First, when power is supplied to the respective sections of the system, a pulse signal generated from the control unit 15 so that the motor of the motor unit 14 is driven to move the parallel moving mechanism 12 in parallel and to rotate the rotary mechanism 11 through the arm 3.
When the parallel moving mechanism 12 reaches a certain position, the switch 13 is turned ON. The position at which the switch 13 is turned ON, is assumed to be an origin position. When the switch 13 is turned ON, the switch outputs an origin detecting signal S.sub.G. The control unit 15, when recognizing the origin detecting signal S.sub.G, stops the output of the pulse signal to stop the motor. At the same time, the controller outputs a reset signal R.sub.e to reset the encoder of the motor unit 14. The then oscillation wavelength is measured by a wavelength meter and a measured value .lambda..sub.O is assumed to be an origin wavelength .lambda..sub.O.
After this, the wavelength .lambda..sub.O is set at the origin position.
When the wavelength is varied, it is relatively changed with the respect to .lambda..sub.O as a reference.
That is, the control unit 15 calculates a difference between a set wavelength .lambda..sub.SET (referred to as the set wavelength, hereinafter) and the origin wavelength .lambda..sub.O, and outputs to the motor of the motor unit 14 a pulse for causing the parallel moving mechanism 12 to be moved to a position corresponding to the set wavelength .lambda..sub.SET. Further, the encoder of the motor unit 14 outputs always to the control unit 15 a signal S indicative of the movement amount of the parallel moving mechanism 12 moved by the motor, and the control unit 15 can recognize the current set wavelength based on the signal S.
In FIG. 10, the aforementioned sine bar mechanism is employed so that the parallel movement of the parallel moving mechanism 12 in the arrow X direction causes change of the rotational angle 2 of the diffraction grating 2 and at the same time, as seen from the above equation (3), adjustment of the external resonator length L in response to a change in 2 realizes continuous variable wavelength without mode hop.
In the prior art external resonator type variable-wavelength LD light source, however, the oscillation wavelength varies due to the following reasons and thus the wavelength reproducibility is deteriorated.
In this connection, an error .DELTA..lambda..sub.MA is expressed as follows . EQU .DELTA..lambda..sub.MA =.DELTA..lambda..sub.M (T.sub.O)+.DELTA..lambda..sub.M (I.sub.LD)+.DELTA..lambda..sub.M (S)(5)
where, .DELTA..lambda..sub.M (T.sub.O) is a change in the oscillation wavelength caused by thermal expansion involved by a temperature change in the entire light source unit, .DELTA..lambda..sub.M (I.sub.LD) is a change in the oscillation wavelength caused by a change in the LD driving current, and .DELTA..lambda..sub.M (S) is a shift of an actual oscillation wavelength from the set wavelength (encoder output value), caused by mechanical factors.
First one of the error causes is expressed by .DELTA..lambda..sub.M (T.sub.O). In the prior art variable-wavelength LD light source, the wavelength accuracy and wavelength reproducibility are guaranteed only at a constant temperature (e.g., 25.degree. C.), so that the thermal expansion and refractive index change caused by the temperature change of the entire light source unit cause change of "n" and "L" in the afore-mentioned equation (1), thus changing the oscillation wavelength .lambda..sub.M.
Assuming that a change in the external resonator length is denoted by .DELTA.(n.times.L), then .DELTA..lambda..sub.M (T.sub.O) is expressed, as follows, from the afore-mentioned equation (1). EQU .DELTA..lambda..sub.M (T.sub.O)=(.lambda..sub.M /(n.times.L).times..DELTA.(n.times.L) (6)
In this case, in the variable-wavelength LD light source unit 19 shown in FIG. 10, mechanical parts are made of mainly invar material having a low thermal expansion coefficient, but the motor of the motor unit 14, diffraction grating 2, lenses 5 and 6, LD 1, etc. are made of stainless steel, glass, quartz, etc. respectively.
In case that the thermal expansion coefficient of the external resonator including its refractive index change is about 5.times.10.sup.-6 and "n.times.L" in the above equation (1) is 30 mm when the variable-wavelength LD light source unit 19 is designed by using the above-described mechanical parts, "n.times.L" varies with a rate of 0.15 .mu.m/.degree.C.
When the light source is used at a temperature in the range of 25.+-.5.degree. C., .DELTA.(n.times.L).apprxeq.1.5 .mu.m. Hence, if .lambda..sub.M =1550 nm, then the wavelength varies by .DELTA..lambda..sub.M (T.sub.O)=0.07 nm in accordance with the afore-mentioned equation (6).
Second one of the error causes comes from .DELTA..lambda..sub.M (I.sub.LD) in the afore-mentioned equation (5), which results from a change in the LD driving current.
Assuming now that a rate of change of oscillation wavelength to the change of the LD driving current is denoted by d.lambda..sub.M /dI.sub.LD and a change in the LD driving current is denoted by .DELTA.I.sub.LD, then .DELTA..lambda..sub.M (I.sub.LD) is written as follows. EQU .DELTA..lambda..sub.M (I.sub.LD)=(d.lambda..sub.M /dI.sub.LD).times..DELTA.I.sub.LD (7)
As a specific value for the rate of change of the oscillation wavelength to the LD driving current change, for example, d.lambda..sub.M /dI.sub.LD was about 2 pm/mA as an actually measured value of a DFB single laser.
The afore-mentioned equation (1) is rewritten with use of parameters in FIG. 12, as follows. EQU .lambda..sub.M =2.times.(n.sub.O .times.L.sub.O +n.sub.LD .times.L.sub.LD)/M(8)
where n.sub.O is the refractive index (=1) of air, n.sub.LD is the refractive index of the LD, L.sub.O is "L-L.sub.LD " in FIG. 12, and L.sub.LD is the physical length of the LD.
In the case where d.lambda..sub.M /dI.sub.LD for the above single laser is considered as the external resonator type LD light source, if L.sub.LD =300 .mu.m, n.sub.LD =3.54, L=30 mm, n.sub.O =1 and .lambda..sub.M =1550 nm, then d.lambda..sub.M /dI.sub.LD .apprxeq.0.07 pm/mA in accordance with the above equations (1) and (8).
Assume now that the LD driving current is constant and the oscillation wavelength was changed by 100 nm. Then an optical output P.sub.0 is changed by about 1 mW from 4 mW as shown in FIG. 13 due to, e.g., wavelength.
In order to make the optical output constant, it is necessary to change the LD driving current as shown in FIG. 14. A relationship between P.sub.0 and I.sub.LD is as shown in FIG. 15, that is: EQU .DELTA.P.sub.0 /.DELTA.I.sub.LD .apprxeq.0.1 mW/mA (9)
Where .DELTA.P.sub.0 denotes an optical output change. Since .DELTA.P.sub.0 .apprxeq.=3 mW, .DELTA.I.sub.LD .apprxeq.30 mA.
Hence the wavelength is changed by .DELTA.I.sub.LD (I.sub.LD).apprxeq.2 pm in accordance with the above equation (7).
Third one of the error causes is .DELTA..lambda..sub.M (S) in the above equation (5), which is generated, in such an arrangement as shown in FIG. 10, by mechanical factors when the parallel moving mechanism 12 and rotary mechanism 1 are finely moved by the motor of the motor unit 14 to change the oscillation wavelength.
Theoretically, as shown by a dotted line in FIG. 16, the set wavelength .lambda..sub.SET corresponding to the output value of the encoder of the motor unit 14 and its actual oscillation wavelength vary proportionally in a 1:1 relationship; but they actually vary as shown by a solid line in FIG. 16.
The above-described 3 errors cause deterioration of the wavelength reproducibility. When the deterioration of the wavelength accuracy is taken into account, it becomes necessary, in addition to the above 3 errors, to take into consideration the error of .lambda..sub.O corresponding to the origin at the time of turning ON the power supply.
With regard to .lambda..sub.O, mechanical factors cause an random error in the external resonator length L in the equation (1).
Assuming now that a change in the external resonator length is denoted by .DELTA.L and an origin wavelength error is denoted by .DELTA..lambda..sub.O, then the following equation is satisfied in accordance with the equation (1). EQU .DELTA..lambda..sub.O =(.lambda..sub.O /L).times..DELTA.L (10)
When .lambda..sub.O =1550 nm, L=30 mm and the random error .DELTA.L=1 .mu.m, .DELTA..lambda..sub.O .apprxeq.0.05 nm in accordance with the equation (10).
In this case, an error of about 0.05 nm takes place for all the oscillation wavelengths .lambda..sub.M.
However, this error is not reproducible so that, if compensation is required, then it is necessary to re-measure the origin wavelength .lambda..sub.O each time the power supply is turned ON with use of a wavelength meter.
This may allow compensation of an error in the wavelength accuracy, but this also involves a large-scale light source with high costs, which is not practical.

External resonator type of variable-wavelength semiconductor laser light source


Non-limiting examples of the present disclosure describe creation and management of a contact associated with a document. A contact for a document in a first application may be created. The contact may be used to add content, from a second application, to the document. The contact may be stored. Contact data for the contact may be transmitted to one or more processing devices. An exemplary created contact may be used to transfer content from one or more applications to a document of another application. Other examples are also described.

User research is showing communication in collaborative projects frequently occurs in applications that are beyond a single document. Collaboration for projects may span multiple applications and include content in different formats. If collaboration occurs outside of an application for a document, the document is empty and unaware of communications that are external to the document. In that case, when a user sits down to work on a document, the user has to recall in which application the communication occurred. Further, the user has to perform additional steps to transfer the content from one application to a document in a different application. In such cases, much of the context of the communication may be lost. It is with respect to the general technical environment of improved processing for devices that transfer data between applications that the present application is directed.

This patent is subject to a terminal disclaimer.


A drug-containing pharmaceutical tablet adapted for accurate breaking which has two or more segments with at least one segment containing a drug.

The subject invention derives from the need to solve at least two related problems within the pharmaceutical industry: (1) inaccurate or inconsistent dose division upon breaking of a dosage form, and (2) inflexibility in adjusting the dose of only one active ingredient in a combination dosage form.
With regard to the first problem of inconsistent or inaccurate dose division, it is known that pharmaceutical tablets are commonly broken to modify the dose provided in a whole tablet. In the U.S., many "managed care" insurance organizations recommend or encourage patients to split or divide tablets, including unscored or irregularly-shaped tablets. These dosage adjustments, achieved through tablet breaking by patients, have been determined to be imprecise. No known solution to the problem has been provided.
Tablets are often produced with a score to aid breaking, but such tablet breaking is well-documented to suffer many problems whether or not scoring of the tablet is provided. Scored pharmaceutical tablets, layered or non-layered, fail to adequately address the problem because of uneven breaking, chipping, or crumbling that occurs upon breaking. Scores formed into a tablet have heretofore not exceeded 1 mm in depth.
In 1984, Stimpel, et al., found that tablet breaking was not accurate, even if performed by a sophisticated, dexterous person. M. Stimpel, et al., "Breaking Tablets in Half." The Lancet (1984):1299.
In a report by Peek et al., "elderly patients" aged 50-79 using, without specific instruction, mechanical tablet splitters to break scored tablets produced highly unsatisfactory division of the tablets. Peek, B. T., Al-Achi, A., Coombs, S. J. "Accuracy of Tablet Splitting by Elderly Patients," The Journal of the American Medical Association 288 No. 4 (2002):139-145. Many drugs, such as warfarin, require dosage adjustments. Peek, et al. found warfarin 5 mg was, on average, split into 1.9 and 3.1 mg tablets. This potent anticoagulant has such a narrow therapeutic range that 2, 2.5, and 3 mg tablet doses are manufactured. Biron, et al., demonstrated that warfarin 10 mg also often split to less than 4.25 or greater than 5.75 mg. Biron, C., Liczner, P., Hansel, S., Schved, J. F., "Oral Anticoagulant Drugs: Do Not Cut Tablets in Quarters," Thromb. Haemost. 1201 (1999). In addition, a statistically significant loss of mass resulted from crumbling or chipping when breaking the warfarin tablets.
Rodenhuis, et al., observed that, in 1998, European regulatory authorities started a policy to discourage scoring of tablets. N. Rodenhuis et al., "The rationale of scored tablets as dosage form." European J. of Pharmaceutical Sciences 21 (2004):305-308. Rodenhuis, et al., attributed the new policy to reports of "bad functioning score lines," "tablets difficult to break," and "unsatisfactory mass uniformity of the subdivided halves." Rodenhuis, et al. noted that "[i]mproving the functioning of score lines may be a more practical approach than banning this [scored] dosage form".
A second problem arising from dividing or breaking of tablets relates to combination drug products, i.e., single or unitary dosage forms containing two or more active ingredients. Combination dosage forms are typically produced as homogeneous mixtures or as capsules. A physician prescribing these homogeneously mixed combination products is unable to adjust the dose of only one of the active ingredients without a proportional adjustment to the dose of the other active ingredient(s). Even if the actives are layered separately, the layer configuration of currently available combination dosage forms results in dividing all layers, thus dividing all active ingredients proportionally. Combination dosage forms can thus be disadvantageous due to the inflexibility for dose adjustment. This disadvantage has hindered the acceptability of certain combination products. Nevertheless, combination treatments for hypertension have proven popular for cost and potential compliance reasons.
Combination products having at least two layers comprising active drug, and a third inactive layer are known. However, these dosage forms comprise the inactive layer interposed as a separating layer between the actives and only serve as a barrier between physical or chemical incompatible active drug-containing layers. The barrier layer does not serve as a means to enable a method of providing a partial dose of the drug or drugs in the combination product.
U.S. Pat. No. 5,738,874 to Conte, et al. describes a multi-layer controlled release tablet having a first layer comprising an immediate release drug composition, a second layer comprising a slow release drug composition, and a third layer comprising a barrier composition to modify release of drug from the adjacent layer. This third, drug-free layer is not interposed between the drug-containing layers and is not useful for facilitating breakage or splitting of the tablet to provide accurately divided doses.
US Patent Application, Pub. No. 2005/0019407A1 describes a composite dosage form having first and second portions joined at an interface. These dosage forms have a first molded material and a second compressed material. No disclosure is provided to teach or suggest modifying the dosage forms to facilitate the breaking or subdividing the dosage forms or providing a partial dose.
U.S. Pat. No. 6,602,521 describes a multiplex drug delivery system containing at least two immediate release drug dosage packages enveloped by a scored, extended release compartment. There is no teaching from the disclosure of this patent of a controlled release compartment which does not envelop the immediate release compartments.
Accordingly, there is a need for combination products which can provide the flexibility of adjusting the dose of one of the actives without necessarily adjusting the dose of the other active(s) contained within the combination dosage form.
The present invention, as disclosed herein, can overcome or alleviate the problems discussed above, and can provide additional advantages and address other problems as would be well understood and recognized from this disclosure by persons of ordinary skill in this art.

Method of administering a partial dose of a segmented pharmaceutical tablet


A sealing technique is provided for forming complex and multiple seal configurations for fuel cells and other electrochemical cells. To provide a seal, for sealing chambers for oxidant, fuel and/or coolant, a groove network is provided extending through the various elements of the fuel cell assembly. A source of seal material is then connected to an external filling port and injected into the groove network, and the seal material is then cured to form the seal. There is thus formed a “seal in place”, that is robust and can accommodate variations in tolerances and dimensions, and that can be bonded, where possible, to individual elements of the fuel cell assembly. This avoids the difficulty, labor intensive cost and complexity of manually assembling many individual gaskets into complex groove shapes and the like. The seal material can be selected to be comparable with a wide variety of gases, liquid coolants and the like.

There are various known types of fuel cells. One form of fuel cell that is currently believed to be practical for usage in many applications is a fuel cell employing a proton exchange membrane (PEM). A PEM fuel cell enables a simple, compact fuel cell to be designed, which is robust, which can be operated at temperatures not too different from ambient temperatures and which does not have complex requirements with respect to fuel, oxidant and coolant supplies.
Conventional fuel cells generate relatively low voltages. In order to provide a useable amount of power, fuel cells are commonly configured into fuel cell stacks, which typically may have 10, 20, 30 or even 100's of fuel cells in a single stack. While this does provide a single unit capable of generating useful amounts of power at usable voltages, the design can be quite complex and can include numerous elements, all of which must be carefully assembled.
For example, a conventional PEM fuel cell requires two flow field plates, an anode flow field plate and a cathode flow field plate. A membrane electrode assembly (MEA), including the actual proton exchange membrane is provided between the two plates. Additionally, a gas diffusion media (GDM) is provided, sandwiched between each flow field plate and the proton exchange membrane. The gas diffusion media enables diffusion of the appropriate gas, either the fuel or oxidant, to the surface of the proton exchange membrane, and at the same time provides for conduction of electricity between the associated flow field plate and the PEM.
This basic cell structure itself requires two seals, each seal being provided between one of the flow field plates and the PEM. Moreover, these seals have to be of a relatively complex configuration. In particular, as detailed below, the flow field plates, for use in the fuel cell stack, have to provide a number of functions and a complex sealing arrangement is required.
For a fuel cell stack, the flow field plates typically provide apertures or openings at either end, so that a stack of flow field plates then define elongate channels extending perpendicularly to the flow field plates. As a fuel cell requires flows of a fuel, an oxidant and a coolant, this typically requires three pairs of ports or six ports in total. This is because it is necessary for the fuel and the oxidant to flow through each fuel cell. A continuous flow through ensures that, while most of the fuel or oxidant as the case may be is consumed, any contaminants are continually flushed through the fuel cell.
The foregoing assumes that the fuel cell would be a compact type of configuration provided with water or the like as a coolant. There are known stack configurations, which use air as a coolant, either relying on natural convection or by forced convection. Such cell stacks typically provide open channels through the stacks for the coolant, and the sealing requirements are lessened. Commonly, it is then only necessary to provide sealed supply channels for the oxidant and the fuel.
Consequently, each flow field plate typically has three apertures at each end, each aperture representing either an inlet or outlet for one of fuel, oxidant and coolant. In a completed fuel cell stack, these apertures align, to form distribution channels extending through the entire fuel cell stack. It will thus be appreciated that the sealing requirements are complex and difficult to meet. However, it is possible to have multiple inlets and outlets to the fuel cell for each fluid depending on the stack/cell design. For example, some fuel cells have 2 inlet ports for each of the anode, cathode and coolant, 2 outlet ports for the coolant and only 1 outlet port for each of the cathode and anode. However, any combination can be envisioned.
For the coolant, this commonly flows across the back of each fuel cell, so as to flow between adjacent, individual fuel cells. This is not essential however and, as a result, many fuel cell stack designs have cooling channels only at every 2nd, 3rd or 4th (etc.) plate. This allows for a more compact stack (thinner plates) but may provide less than satisfactory cooling. This provides the requirement for another seal, namely a seal between each adjacent pair of individual fuel cells. Thus, in a completed fuel cell stack, each individual fuel cell will require two seals just to seal the membrane electrode assembly to the two flow field plates. A fuel cell stack with 30 individual fuel cells will require 60 seals just for this purpose. Additionally, as noted, a seal is required between each adjacent pair of fuel cells and end seals to current collectors. For a 30 cell stack, this requires an additional 31 seals. Thus, a 30 cell stack would require a total of 91 seals (excluding seals for the bus bars, insulator plates and endplates), and each of these would be of a complex and elaborate construction. With the additional gaskets required for the bus bars, insulator plates and endplates the number reaches 100 seals, of various configurations, in a single 30 cell stack.
Commonly the seals are formed by providing channels or grooves in the flow field plates, and then providing prefabricated gaskets in these channels or grooves to effect a seal. In known manner, the gaskets (and/or seal materials) are specifically polymerized and formulated to resist degradation from contact with the various materials of construction in the fuel cell, various gasses and coolants which can be aqueous, organic and inorganic fluids used for heat transfer. However, this means that the assembly technique for a fuel cell stack is complex, time consuming and offers many opportunities for mistakes to be made. Reference to a resilient seal here refers typically to a floppy gasket seal molded separately from the individual elements of the fuel cells by known methods such as injection, transfer or compression molding of elastomers. By known methods, such as insert injection molding, a resilient seal can be fabricated on a plate, and clearly assembly of the unit can then be simpler, but forming such a seal can be difficult and expensive due to inherent processing variables such as mold wear, tolerances in fabricated plates and material changes. In addition custom made tooling is required for each seal and plate design.
An additional consideration is that formation or manufacture of such seals or gaskets is complex. There are typically two known techniques for manufacturing them.
For the first technique, the individual gasket is formed by molding in a suitable mold. This is relatively complex and expensive. For each fuel cell configuration, it requires the design and manufacture of a mold corresponding exactly to the shape of the associated grooves in the flow field plates. This does have the advantage that the designer has complete freedom in choosing the cross-section of each gasket or seal, and in particular, it does not have to have a uniform thickness.
A second, alternative technique is to cut each gasket from a solid sheet of material. This has the advantage that a cheaper and simpler technique can be used. It is simply necessary to define the shape of the gasket, in a plan view, and to prepare a cutting tool to that configuration. The gasket is then cut from a sheet of the appropriate material of appropriate thickness. This does have the disadvantage that, necessarily, one can only form gaskets having a uniform thickness. Additionally, it leads to considerable wastage of material. For each gasket, a portion of material corresponding to the area of a flow field plate must be used, yet the surface area of the seal itself is only a small fraction of the area of the flow field plate.
A fuel cell stack, after assembly, is commonly clamped to secure the elements and ensure that adequate compression is applied to the seals and active area of the fuel cell stack. This method ensures that the contact resistance is minimized and the electrical resistance of the cells are at a minimum. To this end, a fuel cell stack typically has two substantial end plates, which are configured to be sufficiently rigid so that their deflection under pressure is within acceptable tolerances. The fuel cell also typically has current bus bars to collect and concentrate the current from the fuel cell to a small pick up point and the current is then transferred to the load via conductors. Insulation plates may also be used to isolate, both thermally and electrically, the current bus bars and endplates from each other. A plurality of elongated rods, bolts and the like are then provided between the pairs of plates, so that the fuel cell stack can be clamped together between the plates, by the tension rods. Rivets, straps, piano wire, metal plates and other mechanisms can also be used to clamp the stack together. To assemble the stack, the rods are provided extending through one of the end plates. An insulator plate and then a bus bar (including seals) are placed on top of the endplate, and the individual elements of the fuel cell are then built up within the space defined by the rods or defined by some other positioning tool. This typically requires, for each fuel cell, the following steps:
(a) placing a seal to separate the fuel cell from the preceding fuel cell;
(b) locating a flow field plate on the seal;
(c) locating a seal on the first flow field plate;
(d) placing a GDM within the seal on the flow field plate;
(e) locating a membrane electrode assembly (MEA) on the seal;
(f) placing an additional GDM on top of the MEA;
(g) preparing a further flow field plate with a seal and placing this on top of the membrane electrode assembly, while ensuring the seal of the second plate falls around the second GDM;
(h) this second or upper flow field plate then showing a groove for receiving a seal, as in step (a).
This process needs to be repeated until the last cell is formed and it is then topped off with a bus bar, insulator plate and the final end plate.
It will be appreciated that each seal has to be carefully placed, and the installer has to ensure that each seal is fully and properly engaged in its sealing groove. It is very easy for an installer to overlook the fact that a small portion of a seal may not be properly located. The seal between adjacent pairs of fuel cells, for the coolant area, may have a groove provided in the facing surfaces of the two flow field plates. Necessarily, an installer can only locate the seal in one of these grooves, and must rely on feel or the like to ensure that the seal properly engages in the groove of the other plate during assembly. It is practically impossible to visually inspect the seal to ensure that it is properly seated in both grooves.
As mentioned, it is possible to mold seals directly onto the individual cells. While this does offer an advantage during assembly when compared to floppy seals, such as better tolerances and improved part allocation, it still has many disadvantages over the technique of the present invention namely, alignment problems with the MEA, multiple seals and molds required to make the seals and more steps are required for a completed product than the methods proposed by the present invention.
Thus, it will be appreciated that assembling a conventional fuel cell stack is difficult, time consuming, and can often lead to sealing failures. After a complete stack is assembled, it is tested, but this itself can be a difficult and complex procedure. Even if a leak is detected, this may initially present itself simply as an inability of the stack to maintain pressure of a particular fluid, and it may be extremely difficult to locate exactly where the leak is occurring, particularly where the leak is internal. Even so, the only way to repair the stack is to disassemble it entirely and to replace the faulty seal. This will result in disruption of all the other seals, so that the entire stack and all the different seals then have to be reassembled, again presenting the possibility of misalignment and failure of any one seal.
A further problem with conventional techniques is that the clamping pressure applied to the entire stack is, in fact, intended to serve two quite different and distinct functions. These are providing a sufficient pressure to ensure that the seals function as intended, and to provide a desired pressure or compression to the gas diffusion media, sandwiched between the MEA itself and the individual flow field plates. If insufficient pressure is applied to the GDM, then poor electrical contact is made; on the other hand, if the GDM is over compressed, flow of gas can be compromised. Unfortunately, in many conventional designs, it is only possible to apply a known, total pressure to the overall fuel cell stack. There is no way of knowing how this pressure is divided between the pressure applied to the seals and the pressure applied to the GDM. In conventional designs, this split in the applied pressure depends entirely upon the design of the individual elements in the fuel cell stack and maintenance of appropriate tolerances. For example, the GDM commonly lie in center portions of flow field plates, and if the depth of each center portion varies outside acceptable tolerances, then this will result in incorrect pressure being applied to the GDM. This depth may depend to what extent a gasket is compressed also, affecting the sealing properties, durability and lifetime of the seal.
For all these reasons, manufacture and assembly of conventional fuel cells is time consuming and expensive. More particularly, present assembly techniques are entirely unsuited to large-scale production of fuel cells on a production line basis.

Apparatus for and method of forming seals in fuel cells and fuel stacks


A computer network includes an inside network and an external network. The inside network may communicate with the external network over a first path through a first inner load balancer, a first set of firewalls, and a second outer load balancer. The inside network may also communicate with the external network over a second path through a second inner load balancer, a second set of firewalls, and a second outer load balancer. In normal operating conditions, traffic is flowing on both the first and second paths. Probes are passed over each path to monitor the operating status of the path. If a failure occurs in the first inner load balancer, its operating status is changed to standby and the second inner load balancer becomes active for the traffic previously handled by the first inner load balancer. The associated first outer load balancer, recognizing that a probe has not been received to indicate an operating state of the first path, changes its state to standby so that the second outer load balancer becomes active for the traffic previously handled by the first outer load balancer.

Network topologies that use a single firewall between a secure internal network and an external network can create a performance bottleneck and a single point of failure. The single firewall may be replaced by a bank of firewalls to increase throughput and provide redundancy. Moreover, network devices such as firewall load balancers can balance the traffic flow across the firewalls in the bank. Firewall load balancers are typically placed on either side of the bank of firewalls between the secure internal network and the external network. A network design with a single firewall load balancer on each side of the bank of firewalls results in two single points of failure at the inside network firewall load balancer and the outside network firewall load balancer.
Conventional firewall load balancing solutions offer an active-passive redundancy design to eliminate single points of failure that may affect the performance of the network. With active-passive redundancy, there are at least two firewall load balancers on each side of the bank of firewalls. For example, a first inside network firewall load balancer handles the traffic flow while a second inside network firewall load balancer is in a standby mode and does not handle traffic unless a failure occurs in the first inside network firewall load balancer. A hot standby routing protocol (HSRP), or other similar protocols, may be used to change the active/standby status of each inside network firewall load balancer. The second inside network firewall load balancer will pick up the traffic flow to and from the inside network. By changing the operating status of the first inside network load balancer from active to standby and the second inside network firewall load balancer from standby to active, typically there is no affect on the active and standby status of first and second outside network firewall load balancers.
Active-passive network designs leave network devices sitting idle. Idle devices are a waste of resources. Additionally, concerns exist that the standby load balancer may not load balance correctly when it becomes active due to misconfigurations, wiring problems, or other possible failures. Therefore, it is desirable to provide failure protection for network traffic without having idle devices in the network design.

System and method for providing path protection of computer network traffic


The present invention relates to a card-type terminal such as a PC card with a memory card such as a USIM card. It allows a memory card to be secured easily on a tray and inserted easily into a card-type terminal. A card-type terminal includes a tray slidable in and out freely with a memory card mounted, and a guide which helps the tray slide in and houses the inserted tray; in which the memory card is placed on the tray, which is slid into the guide, thereby installing the memory card in the card-type terminal. The tray has a holder which secures, to the tray, the forward-end center section of the memory card mounted along the insertion direction of the tray and an elastic restraining piece which secures, to the tray, the backward-end center section of the memory card mounted along the insertion direction of the tray.

1. Field of the Invention
The present invention relates to a card-type terminal such as a PC card in which a memory card such as a USIM card is installed.
2. Description of the Related Art
Card-type terminals, such as PC cards, equipped with wireless communications capabilities have been used recently. Taking a PC card as an example, it is equipped with wireless communications capabilities for accessing the Internet and is used being inserted in a slot in a notebook personal computer or the like. A memory card called a USIM card is inserted removably in the PC card to store personal information about Internet accesses.
Conventionally, card-type terminals in which a memory card is mounted include those which involve placing the memory card on a tray and inserting the tray, with the memory card placed, into the main body of the card-type terminal through a loading slot.
However, with this type of card-type terminal, the memory card is simply placed on the tray without being secured to it. Consequently, when the user tries to insert the tray, the memory card can easily fall off the tray or become displaced, causing the user to have trouble inserting the tray properly.
Another known type of conventional card-type terminal involves inserting a memory card alone directly into the main body of the card-type terminal through a loading slot. In this case, the memory card, which is small and thin, is not convenient for insertion and withdrawal. Also, the card-type terminal has sharp part of its metal cover exposed in the loading slot, which may damage a memory card when the memory card is inserted.
To solve the problems which can occur when plugging or unplugging a memory card into/from these card-type terminals, a configuration has been proposed which involves inserting a tray into the main body of the card-type terminal with a memory card mounted on the tray and securing the memory card to the tray when it is mounted (see Japanese Patent Laid-Open No. 10-154210).
However, the structure for securing a memory card to the tray proposed in Japanese Patent Laid-Open No. 10-154210 uses hooks protruding toward the center of the tray from both ends of the tray in a direction parallel to the insertion direction of the tray, and thus the memory card is mounted on the tray from a side rather than along the insertion direction of the tray, resulting in poor operability. Also, with the technique disclosed in Japanese Patent Laid-Open No. 10-154210, the loading slot in the main body of the card-type terminal is open wider upward by the thickness of the hooks, increasing the thickness of the main body of the card-type terminal.


A transferring method including providing a substrate, forming a transferred layer over the substrate, joining a transfer member to the transferred layer, and removing the transferred layer from the substrate. The transferring method further includes transferring the transferred layer to the transfer member and reusing the substrate for another transfer. The transferring method may also include providing a substrate, forming a separation layer over the substrate, forming a transferred layer over the separation layer, and partly cleaving the separation layer such that a part of the transferred layer is transferred to a transfer member in a given pattern. The transferring method may also include joining a transfer member to the transferred layer, removing the transferred layer from the substrate and transferring the transferred layer to the transfer member, these of which constitute a transfer process, the transfer process being repeatedly performed.

1. Field of Invention
The present invention relates to a method for exfoliating a detached member, and in particular, a transferring method for exfoliating a transferred layer comprising a thin film such as a functional thin film and for transferring it onto a transfer member such as a transparent substrate. Also, the present invention relates to a transferring method of a thin film device, a thin film device, a thin film integrated circuit device, and a liquid crystal display device produced using the same.
2. Description of Related Art
Production of liquid crystal displays using thin film transistors (TFTs), for example, includes a step for forming thin film transistors on a transparent substrate by a CVD process or the like.
The thin film transistors are classified into those using amorphous silicon (a-Si) and those using polycrystalline silicon (p-Si), and those using polycrystalline silicon are classified into those formed by a high temperature process and those formed by a low temperature process.
Since the formation of such thin film transistors on a substrate involves treatment at a relatively high temperature, a heat resistant material, that is, a material having a high softening point and a high melting point must be used as the transparent substrate. At present, in the production of TFTs by high temperature processes, transparent substrates composed of quartz glass which are sufficiently resistive to a temperature of approximately 1,000° C. are used. When TFTs are produced by low temperature processes, the maximum process temperature is near 500° C., hence heat-resisting glass which is resistive to a temperature near 500° C. is used.
As described above, a substrate for use in forming thin film devices must satisfy the conditions for producing these thin film devices. The above-mentioned "substrate" is, however, not always preferable in view of only the steps after fabrication of the substrate provided with thin film devices is completed.
For example, in the production process with high temperature treatment, quartz glass or heat-resisting glass is used, however, they are rare and very expensive materials, and a large transparent substrate can barely be produced from the material.
Further, quartz glass and heat-resisting glass are fragile, easily broken, and heavy. These are severe disadvantages when a substrate provided with thin film devices such as TFTs is mounted into electronic units. There is a gap between restriction due to process conditions and preferred characteristics required for products, hence it is significantly difficult to satisfy both the restriction and characteristics.
The present invention has been achieved in view of such a problem, and has an object to provide an exfoliating method, which permits easy exfoliation regardless of characteristics of the detached member and conditions for exfoliating, and transferring to various transfer members. Another object is to provide a novel technology which is capable of independently selecting a substrate used in production of thin film devices and a substrate used when the product is used (a substrate having preferable properties for use of the product). A further object is to provide a novel technology not causing deterioration of characteristics of thin film devices which are transferred onto a substrate, by decreasing the optical energy radiated to the separable layer causing ablation in the transferring process.

Exfoliating method, transferring method of thin film device, and thin film device, thin film integrated circuit device, and liquid crystal display device produced by the same


A new, facile, general one-phase method of generating thiol-functionalized transition metal nanoparticles and surface modified by (co)polymers synthesized by the RAFT method is described. The method includes the steps of forming a (co)polymer in aqueous solution using the RAFT methodology, forming a collidal transition metal precursor solution from an appropriate transition metal; adding the metal precursor solution or surface to the (co)polymer solution, adding a reducing agent into the solution to reduce the metal colloid in situ to produce the stabilized nanoparticles or surface, and isolating the stabilized nanoparticles or surface in a manner such that aggregation is minimized. The functionalized surfaces generated using these methods can further undergo planar surface modifications, such as fuctionalization with a variety of different chemical groups, expanding their utility and application.

Nanoparticles are of particular interest because of their use as catalysts, photocatalysts, adsorbents, sensors, ferrofluids, and due to their applications in optical, electronic, and magnetic devices. Since the characteristics imparted by the nanoparticles are dependant to a great part on the method of preparation, the synthesis of the nanoparticles can be critical.
Thiol-stabilized nanoparticles, in particular gold nanoparticles (Au—NPS), have been the focus of intense interest lately due to their potential use in the fields of optics, immunodiagnostics, and electronics. There exist a number of examples of small molecule stabilization using alkanethiols on a variety of metal species, including gold and palladium.
Recently, research has been directed to the application of synthetic (co)polymers as stabilization species for metal nanoparticles, such as stable gold colloids prepared by in-situ reduction (Mayer, A. B. R., Eur. Polym. Journal 1998, 34, 103-108); ATR grafting from polymerization to attach polymer chains to gold nanoparticles (Nu, S., et al. Angew. Chem. Int. Ed. 2001, 40, 4016-4018); gold nanoparticles decorated with covalently bound thiol-capped polystyrene macromolecules (Corbierre, M. K, et al. J. Am. Chem. Soc. 2001, 123, 10411-10412); and platinum nanoparticles with long perfluorinated carbon chains (Moreno-Mañas, M., et al. Chem. Commun. 2002, 60-61). However, these examples use processes of "grafting-to" and "grafting-from" for nanoparticle stabilization that utilize living polymerization techniques and suffer from disadvantages such as special reaction conditions, sensitivity to specific monomers, and necessitate expensive reagents and/or monomers.
Additional research in the area of nanoparticle synthesis has focused on the development of "pseudo-living" polymerization methods. Three principal approaches have been described to achieve this pseudo-living free-radical polymerization technique; reversible termination, reversible termination by ligand-transfer, and degenerative chain transfer. The first of these, typically referred to as nitroxide-mediated or stable free-radical polymerization (SFRP) has been exploited in the synthesis of controlled styrenic-based (co)polymers (Solomon, D. H., et al. U.S. Pat. No. 4,581,429; Goto, A.; et al. Macromolecules 1996, 29, 3050; Yoshida, E., et al. J Polym. Sci., Part A: Polym. Chem. 1997, 35, 2371).
Subsequently, several groups disclosed an atom transfer radical polymerization (ATRP) process, which is a radical polymerization with reversible termination by ligand transfer to a metal complex. This technique has been shown to work especially well with styrenic and acrylate-based polymer monomers, similar to SFRP (Wang, J.-S., et al. Macromolecules 1995, 28, 7572; Sawamoto, M., et al., Trends Polym. Sci. 1996, 4, 371; Bandts, J. A. M., et al. J Organomet. Chem. 1999, 584, 246).
Most recently, a third mechanism has been proposed for achieving "pseudo-living" polymerization character, which is a free-radical polymerization with reversible chain transfer (also termed degenerative chain transfer). It has been termed RAFT—reversible addition-fragmentation chain transfer polymerization (Le, T. P., et al., WO Patent 9801478; Chiefari, J., et al. Macromolecules 1998, 31, 5559-5562; Moad, G., et al. Polym. Int. 2000, 49, 993). This technique appears to offer several advantages over the previous ATRP and SFRP techniques, in that a vast array of monomers can be used, and the reaction can be performed under a broad range of experimental conditions using a variety of solvents.
Despite these recent advances, few methods have been described which allow for the covalent attachment of polymer chains directly to transition metal colloids or surfaces (the so-called grafting-to approach), as opposed to simple physical adsorption of a (co)polymer. Thus, there exists a need for a new, facile manner for the preparation of (co)polymer stabilized transition metal nanoparticles and surfaces. The approach described herein takes advantage of the method of polymer synthesis in which the polymers produced bear thiocarbonylthio end groups which can be reduced in situ in the presence of a transition metal sol or surface, yielding a polymer with a thiolate end-group which covalently bonds to the metal colloid or metal surface. This fast, facile, "one-step" synthetic procedure of simultaneous reduction of the polymer end-group and the metal colloid or surface in situ is significantly less demanding than the grafting-from approach which requires initial modification of the metal colloid with a suitable polymerization initiator, followed by subsequent polymerization. This new, rapid one-step method allows for the preparation of polymers suitable for covalent attachment on an industrial scale.

Preparation of transition metal nanoparticles and surfaces modified with (CO) polymers synthesized by RAFT


A mixer assembly (204, 603) for mixing intake air from an intake system (124) with exhaust gas from an exhaust gas recirculation system (134) to yield a mixture stream includes an intake air conduit (202, 700) having an inlet (206, 706) fluidly connected to the intake system. The mixer assembly (204, 603) also includes a mixer (200, 600) having an inlet (208, 702) fluidly connected to the exhaust gas recirculation system (134). The mixer (200, 600) is at least partially disposed in the intake air conduit (202, 700) and includes an outer pipe (203, 604) and a dividing portion (217, 602) disposed within the outer pipe. The dividing portion (217, 602) divides a first passage (216, 612) from at least one second passage (218, 608), the first passage having an outlet (216′, 612′) that is at a first height, and the second passage having an outlet (218′, 608′) that is at a second height.

Most internal combustion engines have some type of emission control device and system. One common type of control system is an exhaust gas recirculation (EGR) system that recirculates exhaust gas from an exhaust system to an intake system of the engine. A high pressure EGR system typically recirculates exhaust gas from upstream of a turbine to downstream of a compressor. Other EGR systems recirculate gas at a low pressure, and are called low-pressure systems. An engine having a high-pressure EGR system has a junction in the air intake system where the EGR gas and the intake air mix to form a mixture. This mixture of exhaust gas and intake air is consumed during engine operation.
Providing each cylinder of an internal combustion engine with a homogeneous mixture of air and exhaust gas is advantageous for operation. A homogeneous mixture promotes efficient operation of the engine because the emission and power output of each cylinder is uniform. The homogeneity of the mixture provided to each cylinder becomes a design parameter of special importance for engines running on a considerable amount of EGR over a wide range of engine operating points.
Many methods devised in the past were intended to improve mixing of exhaust gas with intake air for engines having an EGR system. These methods typically use flow obstructions that increase turbulence in the intake air, the exhaust gas, or the mixture of intake air and exhaust gas, to improve the homogeneity of the mixture supplied to the engine's cylinders. Such methods, although typically fairly effective, have the disadvantage of increasing pressure losses in the intake system of the engine as a result of increased turbulence in the intake air or in the intake mixture. Increased pressure losses in the intake system of an engine leads to decreased engine efficiency and increased fuel consumption.

Multiple height fluid mixer and method of use

International Engine Intellectual Property Company, LLC


A device for trapping reaction products and especially for generating and trapping decomposition products from thermal decomposition processes, including combustion, is described. Decomposition products of a solid sample are formed at the top end of an externally heated vertical decomposition tube and are channeled downward through a region of decreased diameter in which a trapping device is positioned. The trapping device consists of two vertical concentric tubes of which the top end of the inner tube is slightly lower than that of the outer tube. Water flows upward between the two concentric tubes, traps the decomposition products at the top, and drops down through the inner concentric tube. Products contained in the water are collected externally from the lower end of the trapping device for analysis. The insoluble gaseous products are collected by an external vacuum system after passing through the stream of water.

A common analytical procedure is the trapping and analysis of reaction products. Testing and evaluating the toxicity of combustion products emitted by fires, for example, has led to the development of various devices for simulating combustion conditions and collecting the products. The accuracy of subsequent qualitative and quantitative analyses of the combustion products depends on whether the products have been modified before collection and on whether substantially all the products have been trapped and collected.
Combustion product analysis is not limited to determining the amount of carbon dioxide, carbon monoxide, oxygen and water generated, but includes the identification and quantification of biologically hazardous materials contained in the products for toxicity studies. For example, the characterization of the products emitted from burning polymers is necessary for limiting the use of polymers in certain applications.
In addition to combustion product analysis a need exists for the testing of products generated by other chemical reactions, especially high temperature decomposition processes. For example, pyrolysis and certain metallurgical processes such as sintering may emit toxic products requiring identification.
Thus, a device for the efficient and accurate collection of various chemical reaction products and especially for the creation and trapping of products formed by combustion and high temperature decomposition processes is necessary for meaningful subsequent analysis.
The generation and collection of thermal combustion products for analysis has commonly been accomplished using devices which incorporate the method described in DIN 53436. Such devices consist of a long, horizontal quartz combustion tube in which a sample placed in an airstream is continuously decomposed by means of an external moving furnace. The effluents are carried by the airstream from the tube to an external analytical measuring system or, alternatively, are measured by on-line monitors such as infrared detectors.
Problems associated with using the DIN 53436 apparatus include inaccurate qualitative and quantitative analyses of the decomposition products due to the great amount of soot and smoke emitted during combustion of the sample. Such materials strongly adhere to surfaces even slightly cooler than the region in which they were generated. Thus, not all the decomposition products will exit the tube for analysis, and results will be inaccurate. Conventional solvent washing of the combustion tube to collect the adhered material will not increase accuracy because much of the product may polymerize upon contact with the cooler walls of the decomposition tube and remain adhered to the surface.
Another source of error in the analysis of the decomposition products comes from the long transportation time (typically between 25 and 35 minutes) between sample decomposition and product collection. Since the products remain heated at high temperatures while they are slowly carried along the length of the tube, the initial products may polymerize or otherwise be altered before analysis. Thus, the results obtained may include identification of species not actually produced during sample decomposition.
Finally, cleaning the apparatus following the decomposition process is both time-consuming and cumbersome. Since solvent washing will not remove the surface contamination, the components of the device must be reheated in oxygen to temperatures approximating 500.degree. C. to burn off the polymer. Thus, evaluation of multiple samples on the same apparatus in a short amount of time is impossible.
The present invention is a device designed in part to overcome the problems encountered when using conventional apparatus, such as that employed according to DIN 53436 for trapping thermal decomposition products. Sampling of both the organic and inorganic components is more accurate because all the product is collected without modification. The total time from decomposition of the sample to collection is typically less than 10 min; therefore, the products are not likely to polymerize before collection. Also, the apparatus maintenance and cleaning time is greatly reduced.
Reaction gases are channeled from top to bottom of an externally heated vertical external tube by slightly pressurizing the products. Thus, the products do not adhere to the inner walls of the external tube but are forced into a region of decreased diameter at the lower end of the tube. Two concentric tubes reside within the narrow portion of the external tube to trap the products. Introduction of a shield gas at the lower end of the external tube prevents product adherence to both the decreased diameter portion of the external tube and the concentric tubes. The concentric tubes are flushed with water and cooled such that soluble decomposition products are trapped in the water and collected for analysis. Insoluble products remain suspended in the water and may be separated externally. The gaseous products are collected by vacuum after passing through the stream of water.
The use of water in the present invention to trap the reaction products is advantageous in that system temperatures much greater than 1000.degree. C. may be reached in heating the sample. By using an external tube and a sample introduction apparatus consisting of a ceramic material which is heat resistant at high temperatures, the system is made adaptable to such decomposition processes as combustion, sintering or pyrolysis. Because the water cools the concentric tubes through which the products pass before leaving the system, the concentric tubes and the collection vessel may consist of a material such as quartz or glass that is not physically resistant to very high temperatures.
Trapping the reaction products with water is also advantageous because, for example, the actual physiological situation where combustion products are breathed into the lungs is more accurately simulated in the present invention that in the DIN 53436 device. Finally, in the case of combustion where water is a major product of the process, its introduction to trap the sample product adds no new components to the product composition.

Apparatus for the trapping of reaction products


Methods, systems, and apparatus that substantially prevent the fraudulent use of wireless units roaming in visited systems. A visited mobile switching center (MSC-V) registers a wireless unit that is roaming in the visited system, but denies originating communication service to the unit. To make a call, the unit provides a code and identification information. The MSC-V routes the code and identification information to a verification entity. The entity determines whether the wireless unit is a verified or authentic unit. If the wireless unit is a verified unit, the verification entity responds positively to the MSC-V. Based on the verification, the MSC-V removes the denial of originating communication service from the wireless unit. Advantageously, the home system need not be consulted by the MSC-V with respect to the authenticity of the wireless unit.

A distinguishing feature of humans as a species is our ability to communicate with each other. Our methods of communication have become ever more sophisticated and have led to the development of wireless communications. Generally, wireless communications are communications that are transmitted through the use of radio frequency (RF) technology. Wireless communications include communications that are transmitted through the use of wireless units such as cellular telephones, mobile telephones, car phones, personal communication service (PCS) units, pagers, and the like.
A wireless unit is particularly useful to a person on the move. For example, a person may use his or her wireless unit while driving a car. The wireless communications service to the person's wireless unit is provided typically by a service provider that may also be referred to herein as a carrier. Typically, a person who obtains wireless communications service from a service provider is generally referred to herein as a subscriber, a customer, or a user. A subscriber may make or receive communications with his or her wireless unit. The term "communication" is used herein to refer to any call, message, announcement or other exchange of data or information, whether analog or digital, that may be received on a wireless unit or transmitted from a wireless unit, and/or may be received or transmitted from a wireless unit that is operating as part of any other device such as a computer, or the like.
When a user initiates a communication on his or her wireless unit, a base station in or serving a predetermined geographic area wherein the subscriber is located receives the communication. The geographic area that is served with wireless communications service is referred to herein as the service area of the service provider. The service provider typically operates a wireless communications network or system to provide wireless communications service to the geographic area. The wireless communications network includes the referenced base station, and other elements such as the mobile switching centers (MSCs). The wireless communications network also includes elements that interface with the public switched telephone network (PSTN), and other networks and systems so as to provide for communications between and among parties using wireless units, using wireline units, or other communications devices.
Upon receipt of a communication from a wireless unit of a user, the base station transmits the communication to a mobile switching center (MSC) (sometimes referred to as a mobile-service switching center or mobile telecommunications switching office (MTSO)). In response to the receipt of the communication, the MSC further routes the communication as appropriate. This routing may take the communication to and through the PSTN, to and through the same wireless communications system, to and through another wireless communications system, to and through another type of communications system, or combinations thereof.
In addition to making a call, a subscriber may receive a communication on his or her wireless unit from a caller. The caller directs his or her communication to the number associated with the subscriber's wireless unit, which is referred to herein as the mobile number (MN) of the wireless unit. The mobile number may be the mobile identification number (MIN) of the wireless unit. The communication is routed through the PSTN, through other networks, and/or wireless communications systems until the communication reaches the MSC serving the subscriber's wireless unit. This MSC may be referred to as the serving MSC or the serving switch. The serving MSC then further routes the communication to the wireless unit.
As noted, a wireless unit is particularly useful when a subscriber is on the move such as when the subscriber is driving a car. The subscriber's mobility may take the subscriber out of the service area served by the service provider from whom the subscriber subscribes. In other words, the subscriber's mobility may take the subscriber out of his or her home service area served by his or her home service provider or home carrier. The subscriber may move so as to be located in another service area that is served by a different service provider with whom the subscriber has no business relationship. The subscriber is said to be "roaming" out of his or her home service area and may be referred to as a "roamer", "roaming subscriber" in a visited service area that is served by a visited system.
To provide a roaming subscriber with communications service, service providers have agreed to follow certain procedures in the processing of communications with respect to each other's subscribers. Generally, a roaming subscriber is validated and may be authenticated by the visited system, which also may be referred to as the visited service provider. Both of these processes (validation and authentication) are used to prevent fraudulent use of wireless units and for other reasons. General descriptions of these processes and other information about wireless communications systems may be found in the book entitled Cellular and PCS—The Big Picture by Lawrence Harte, Steve Prokup and Richard Levine (McGraw-Hill 1997).
Generally, in validation, when a wireless unit initiates a communication in a service area other than its home service area, the visited system serving that visited service area attempts to find the wireless unit's identification (also referred to as registration information) in the visitor location register (VLR) of an appropriate MSC in the visited system (MSC-V). If the visited system does not find the identification, then the wireless unit is determined to be not registered with the visited system. Prior to being provided with communications service in the visited system, a wireless unit typically needs to be registered in the visited system.
To register the wireless unit in the visited system, the MSC-V takes certain actions. Using the wireless unit's identification (which generally may include its mobile number, and electronic serial number (ESN), and/or mobile identification number (MIN)), the visited system sends a message to the wireless communications system ("home system") which generally provides wireless communications service to the subscriber. The message from the visited system to the home system is a message requesting validation of the visiting wireless unit. The home system typically checks a home location register (HLR) in an appropriate MSC (MSC-H) of its system, and compares the identification regarding the wireless unit to determine if the wireless unit is valid. If the wireless unit is valid, then the HLR of the home MS,C (MSC-H) responds to the serving MSC in the visited system that the validation was successful or positive. The HLR in the home system generally keeps track of the information about the location of its subscriber in a visited system for use in the future routing of calls, etc.
After the serving MSC in the visited system receives confirmation that the visiting wireless unit is valid, the communication initiated by the visiting wireless unit is processed. The VLR of the serving MSC may then temporarily store the visiting wireless unit's information to validate the identity of the wireless unit itself rather than requesting validation from the home system again for the next call from that wireless unit.
The above-described processes of registration including validation of a roaming wireless unit with its home system are efforts that have been generally put into place to assist in the prevention of the fraudulent use of wireless units. Despite these efforts, wireless units, and in particular, wireless units roaming in visited systems are being fraudulently used.
One of the drawbacks of the above-described validation processes is that typically the validation processes cannot detect illegally cloned wireless units or other fraudulent uses of a wireless unit. To combat such fraudulent uses of a wireless unit, a process generally referred to as "authentication" of a wireless unit has been used. Authentication is the exchange and processing of information to confirm a wireless unit's identity and association with a particular subscriber.
An example of authentication is now described with respect to a wireless unit that enters a visited system. The visited system searches for the wireless unit's identification in its VLR and determines that the wireless unit is not registered. The visited system uses the wireless unit's identification (or other information such as authentication information obtained from the wireless unit) to request authentication of identity from the subscriber's home system. The request for authentication may be, separate or may be combined with the request for validation. With respect to authentication, the home system may check an HLR in an appropriate MSC-H of its system and compare the wireless unit's identification or authentication information to stored information to determine if the wireless unit is authentic.
Alternatively, or in addition, the home system or the visited system may check with an authentication center (AC) to determine if the wireless unit is authentic. An authentication center may be an entity of either the home or visited system, or a separate entity. Generally, an authentication center maintains a database, tables, or the like with respect to the identifies of wireless units that are served by the AC. When called upon, the AC compares the identification and/or authentication information which has been provided to the AC with respect to a particular wireless unit, and determines whether the particular wireless unit is authentic based on the comparison.
If the wireless unit is determined to be authentic (whether by the visited system, home system, and/or an AC), then this information is provided to the visited system. The visited system may store for a period of time authentication information relating to the wireless unit in a VLR of an appropriate MSC-V. The visited system then may use this stored authentication information rather than contact the home system and/or an AC again. If the wireless unit is validated and determined to be authentic, then the visited system generally provides communications service to the wireless unit.
If the wireless unit is determined to be in authentic (whether by the visited system, home system, and/or an AC), then this information also is provided to the visited system. In response to the finding of a lack of authenticity of the wireless unit, the visited system may deny communications service to the wireless unit, or the visited system may take other actions with respect to the wireless unit.
But the above-described processes have been considered to be insufficient to prevent the fraudulent uses of a wireless unit, and especially, to substantially prevent the fraudulent uses of a wireless unit roaming in a visited system.
Accordingly, there is a need for methods and systems that provide additional safeguards so as to substantially prevent the fraudulent uses of a wireless unit, and especially as the wireless unit roams in visited systems.

Methods and systems to substantially prevent fraudulent use of a wireless unit roaming in a visited system


Embodiments of the invention relate to systems and methods for cloning a production database for quality assurance (QA) by the merchant users. A QA user may request tokens, card types and other data associated with a payment device for quality assurance purposes. The payment network redirects the QA request to a go-between database that is present between the QA user and the production environment of the payment network rather than pull the information directly from the production environment. As a result, the merchant is able to use tokens for testing, without violating consumer privacy and security rules and regulations (e.g., PCI rules). The QA user does not have to create a customized testing solution.

This application relates to the field of data migration, in particular, data migration from a production environment to lower environments. A production environment is mostly used by different entities (organizations, companies, businesses, financial institutions, etc.) for their processing needs using live applications. Lower environments, such as, quality assurance (QA), development, staging, etc., help ensure that the applications are well tested and stable before being migrated to the production environment.
A QA environment is mostly used to test data, hardware and software that closely simulate the production environment. However, in most cases, access to production data in lower environments is limited due to security reasons. A good example is the consumer data for financial transactions (e.g., payment card information), access to which is highly regulated. Payment card industry (PCI) rules and regulations emphasize the policy for privacy and security concerning consumer data. These rules and regulations restrict merchant users from accessing the consumer data and the production infrastructure associated with securing the consumer data for QA purposes. Quality assurance of the financial transaction system is desirable for the seamless operating of commerce. Similar needs for production infrastructure testing exists in other industries such as medical records, criminal records, vehicle driver information, loan applications, stock trading and voter registration, where access to databases containing sensitive information is regulated.
One of the goals for a user performing QA testing is to test the system and environment as much as possible with the least amount of deviations from the final system that is deployed into the production environment. Any deviation from the production environment introduces a proportionally exponential amount of risk associated with the system when introduced in the production environment. For example, merchant users generate customized testing environments to mimic the production systems and databases implemented by a payment system for testing purposes. However, these testing systems deviate from a production system in a variety of known and also unknown ways. For instance, the QA environment may have code introduced at various stages of the system pipeline to emulate interfaces that interact with the payment system. Also, it would be difficult to emulate all the artifacts of the network lag and system architecture of the payment network that are usually not part of any requirements documentation. These deviations increase the risk that when the system is deployed in a production environment that an error or deficiency that was latent due to the deviations introduced by the QA testing environment would manifest itself while the system is in full production and cause significant loss. Another consideration is the cost associated with architecting, designing and maintaining the QA testing environments for the merchant users.
Embodiments of the invention address this and other problems, individually and collectively.

Database cloning and migration for quality assurance

Visa International Business Machines Corporation