Process for manufacturing olefin polymers, in which some of the suspension of olefin polymer particles formed in a diluent is drawn off from the polymerization reactor and diluted by means of a liquid before being sent into a hydrocyclone separator in which, on the one hand, a concentrated suspension of polymer particles and, on the other hand, a stream essentially comprising diluent are formed and separated.

The present invention relates to a process for manufacturing olefin polymers in suspension in a diluent. The invention also relates to a plant used for carrying out the process.
Patent Application EP 0 891 990 describes a continuous olefin polymerization process in which a suspension comprising up to 52% by weight of polyethylene particles in isobutane is formed in the polymerization reactor and is continuously withdrawn therefrom. This process has the disadvantage that the suspension withdrawn from the reactor still contains a large amount of diluent and of other reactants, such as the monomer, which it is then necessary to subsequently separate from the polymer particles and to treat for the purpose of reusing it in the reactor.
Several techniques used for further concentrating a suspension of polymer particles which has been withdrawn from a polymerization reactor have been described. On an industrial scale, it is general practice to use several settling legs which are mounted directly on the polymerization reactor and are periodically filled and discharged in a sequential manner. However, this process has drawbacks in that the periodic discharging from the reactor is difficult from the safety and reliability standpoints. This is because it is known that the valves isolating the settling legs readily become blocked over time. U.S. Pat. No. 3,816,383 and GB 1 147 019 describe continuous olefin polymerization processes in which a suspension of polyethylene particles, withdrawn from a reactor, is concentrated by means of a hydrocyclone separator, and then a fraction of the concentrated suspension is drawn off for the purpose of recovering the polyethylene produced, the other fraction being recycled to the reactor. These processes have the drawback that the suspension drawn off contains relatively large amounts of diluent and of monomer compared with the amount of polymer produced, these having to be separated and subsequently treated.
The object of the present invention is to provide a process which does not have the aforementioned drawbacks and which makes it possible, in particular, to considerably reduce the amounts of diluent and other reactants to be separated from the polymer particles. The invention therefore relates to a process for manufacturing olefin polymers, in which:
(a) at least one olefin is continuously polymerized in a polymerization reactor in the presence of a diluent (D) in order to produce a suspension (S) comprising the said diluent (D) and olefin polymer particles;
(b) some of the said suspension (S) is drawn off from the reactor;
(c) the suspension drawn off is diluted by means of a liquid (L) so as to obtain a dilute suspension (DS);
(d) the dilute suspension (DS) is sent into a hydrocyclone separator in which, on the one hand, a concentrated suspension (CS) of polymer particles and, on the other hand, a stream (F) comprising diluent (D) are formed and separated;
(e) the stream (F) is drawn off from the hydrocyclone separator and at least partially recycled to the polymerization reactor;
(f) the concentrated suspension (CS) is drawn off from the hydrocyclone separator; and
(g) the olefin polymer particles are separated from the concentrated suspension (CS).
It has been found, surprisingly, that diluting the suspension (S) coming from the polymerization reactor by means of a liquid (L) makes it possible to considerably increase the efficiency of the hydrocyclone separator while at the same time allowing very concentrated suspensions of polymer particles to be obtained at the outlet of the hydrocyclone separator. In the present invention, the term xe2x80x9cliquid (L)xe2x80x9d is understood to mean any compound which is liquid under the temperature and pressure conditions used in the polymerization reactor and in which most of the olefin polymer formed is insoluble under these polymerization conditions.
According to a first method of implementing the process according to the invention, the liquid (L) added in step (c) to the suspension (S) drawn off from the polymerization reactor consists essentially of diluent (D). The amount of diluent added as liquid (L) in this first method of implementing the process may vary widely. In general, the amount of diluent added to the suspension is at least 0.1 1, preferably at least 0.5 1, per kg of polymer particles present in the suspension (S) drawn off from the reactor. The amount of diluent added generally does not exceed 51, and preferably does not exceed 3 1, per kg of polymer particles present in the suspension (S) drawn off from the reactor.
This first method of implementing the process has the additional advantage that the concentration of residual olefin in the concentrated suspension (CS) drawn off downstream of the hydrocyclone separator decreases strongly compared with its polymer particle content and its diluent content. Consequently, the purification and repressurization of the diluent, for the purpose of reusing it in the reactor, are greatly simplified and more economic. In addition, the amount of olefin to be recovered from the concentrated suspension is greatly decreased and therefore the recovery is also simplified and more economic.
According to a second method of implementing the process according to the invention, the liquid (L) added in step (c) to the suspension (S) drawn off from the polymerization reactor consists essentially of at least part of the stream (F). In this second method of implementing the process according to the invention, the amount of stream (F) added to the suspension drawn off from the reactor during step (c) may vary widely. In general, the amount of stream (F) thus added to the suspension is at least 0.1 1, preferably at least 1 1, per kg of polymer particles present in the suspension (S) drawn off from the reactor. The amount of stream (F) added generally does not exceed 201, preferably does not exceed 101, per kg of polymer particles present in the suspension (S) drawn off from the reactor. The fraction of the stream (F) used as liquid (L) is in general between 10 and 99% by weight, the balance being recycled to the polymerization reactor. Preferably, the fraction of the stream (F) used as liquid (L) is at least 25% by weight. Preferably, the fraction of the stream (F) used as liquid (L) does not exceed 95% by weight.
This second method of implementing the process has the additional advantage that the efficiency of the hydrocyclone separator can be varied by modifying the fraction of the stream (F) used as liquid (L). In fact, increasing the fraction of the stream (F) recycled as liquid (L) allows the efficiency of the hydrocyclone separator to be improved. Decreasing the fraction of the stream (F) recycled as liquid (L) reduces the separating power of the hydrocyclone separator so that certain fine polymer particles are entrained by the stream (F) and therefore recycled to the polymerization reactor, this having the effect of increasing the productivity of the catalyst. Another advantage of this second method of implementing the process resides in the fact that controlling the amount of the stream (F) recycled as liquid (L) allows the concentration of polymer particles present in the polymerization reactor to be adjusted. Thus, it is possible to work at relatively low polymer concentrations in the polymerization reactor while maintaining a high polymer concentration at the output end of the process.
According to a third method of implementing the process according to the invention, the liquid (L) added in step (c) to the suspension (S) drawn off from the polymerization reactor consists essentially of diluent (D) and at least part of the stream (F). In this third method of implementing the process according to the invention, the amount of stream (F) and the amount of diluent (D) are generally those described above with respect to the first and the second method of implementing the process, respectively.
The olefin used in polymerization step (a) of the process according to the invention is generally chosen from among olefins containing from 2 to 12 carbon atoms and mixtures thereof. The olefin is preferably chosen from among 1-olefins containing from 2 to 8 carbon atoms, more particularly from among ethylene, propylene, 1-butene, 1-methylpentene, 1-hexene, 1-octene and mixtures thereof. It goes without saying that in step (a) several olefins can be used together or that other monomers copolymerizable with the olefins may be used so as to obtain olefin copolymers. Among other monomers copolymerizable with olefins, mention may especially be made of conjugated or unconjugated diolefins. The process according to the invention is applicable to the production of olefin polymers. The expression xe2x80x9colefin polymersxe2x80x9d is understood to mean both the homopolymers of an olefin and the copolymers of an olefin with one or more other olefins or of other monomers copolymerizable with the olefin. The process is particularly well suited for obtaining ethylene polymers and propylene polymers, and more particularly for obtaining ethylene homopolymers and ethylene copolymers comprising less than 5% by weight of at least one other olefin containing from 3 to 8 carbon atoms.
The diluent (D) used in the process according to the invention may be any diluent which is liquid under the polymerization conditions and in which most of the polymer formed is insoluble under the polymerization conditions. Suitable diluents are hydrocarbons. Aromatic and cyclic aliphatic hydrocarbons containing from 5 to 12 carbon atoms, such as toluene and cyclohexane, are very suitable. Preferred diluents are acyclic aliphatic hydrocarbons containing from 3 to 8 carbon atoms, such as pentane and hexane. Propane and isobutane are particularly preferred.
In one particular case, the diluent may be the olefin itself maintained in the liquid state below its saturation pressure.
In another particular case, the diluent may be maintained in its supercritical state.
The polymerization carried out in step (a) of the process according to the invention is generally carried out in the presence of a catalyst. Any catalyst allowing olefins to be polymerized may be used. By way of examples of such catalysts, mention may be made of catalysts of the Ziegler type, catalysts based on vanadium or chromium, metallocene catalysts and those based on transition metals of Groups 8 to 12 of the Periodic Table of the Elements. These catalysts may be supported on an inorganic or polymeric support.
It goes without saying that in polymerization step (a), apart from the monomer(s) and the diluent, other compounds may be present such as, especially, cocatalysts and agents for controlling the molecular mass.
The polymerization carried out in step (a) of the process may be performed under highly varied temperature and pressure conditions. In general, the polymerization is carried out at a temperature of from 20 to 150xc2x0 C., preferably from 25 to 130xc2x0 C. Usually, the polymerization is carried out at a pressure of from 105 to 100. 105 Pa, preferably from 10. 105 to 55-105 Pa.
According to a variant of the process according to the invention, the polymerization carried out in step (a) is carried out in several polymerization reactors connected in series. The use of several reactors in series is known and has, for example, been described in Patent Application EP 0 603 935. In this case, the suspension (S) drawn off from the last polymerization reactor is sent to step (b). The suspensions coming from each reactor preceding the last polymerization reactor may be drawn off and transferred in any known manner to the next reactor. For this purpose, it may also be advantageous to use hydrocyclone separators. If step (a) is carried out in several reactors in series, the stream (F) may be recycled to the last polymerization reactor. According to one advantageous embodiment, the stream (F) is recycled to a polymerization reactor preceding the last reactor.
In step (b) of the process according to the invention, some of the suspension formed in the reactor in step (a) is drawn off from this reactor. The amount of suspension drawn off from the reactor may vary widely.
In general, the amount of suspension drawn off from the reactor is adjusted so as to correspond to the production of polymer.
Apart from the diluent and the olefin polymer particles, the suspension drawn off from the reactor may contain other compounds present or formed in the polymerization reactor. In general, the suspension comprises an amount of unpolymerized olefin.
In step (b), the suspension is preferably drawn off from the polymerization reactor continuously.
The dilute suspension (DS) formed in step (c) of the process according to the invention comprises, apart from the constituents of the suspension drawn off from the polymerization reactor, the liquid (L).
According to the first method of implementing the process according to the invention, the liquid (L) consists essentially of diluent (D). In this case, the diluent added as liquid (L) may be fresh diluent, i.e. diluent not ever having been used for the polymerization, or recovered and purified diluent. The expression xe2x80x9crecovered and purified diluentxe2x80x9d is understood to mean diluent which has already been used for the polymerization but which is purified so as to separate therefrom most of the compounds present or formed in the polymerization reactor, such as polymer particles and olefin, so that it has a purity sufficient to be reused in the process.
According to the second method of implementing the process, the liquid (L) consists essentially of at least part of the stream (F). The stream (F) comprises, apart from the diluent, other compounds present or formed in the polymerization reactor. In general, the stream (F) comprises compounds present or formed in the reactor which are soluble in the diluent. The stream (F) usually comprises some olefin. The stream (F) may also comprise compounds present or formed in the reactor which are not soluble in the diluent, such as, for example, fine polymer particles.
According to the third method of implementing the process according to the invention, the liquid (L) consists essentially of diluent (D) and of at least part of the stream (F). In this method of implementing the process, the suspension drawn off from the reactor is preferably diluted firstly by means of diluent (D) and then by means of part of the stream (F).
In step (d) of the process according to the invention, the dilute suspension formed in step (c) is sent into a hydrocyclone separator in which, on the one hand, a concentrated suspension (CS) of polymer particles and, on the other hand, a stream (F) comprising diluent (D) are formed and separated.
For the purposes of the present invention, the term xe2x80x9chydrocyclone separatorxe2x80x9d is understood to mean any apparatus which, due to the action of a centrifugal force, makes it possible to separate from a suspension of solid particles, on the one hand, a liquid stream depleted in solid particles and, on the other hand, a stream richer in solid particles. Such apparatuses are well known; they have been described, for example, in Perry""s Chemical Engineers"" Handbook, McGraw-Hill 7th Edition, 1997, pages 19-24 to 19-28. It goes without saying that in the process according to the invention several hydrocyclone separators may be connected in series.
The pressure and temperature values in the hydrocyclone separator are generally adjusted so that most of the diluent present remains in liquid form. Preferably, the pressure and temperature are of the order of magnitude of those obtaining in the polymerization reactor.
In step (e) of the process according to the invention, the stream (F) is drawn off from the hydrocyclone separator and at least partially recycled to the polymerization reactor. In the first method of implementing the process according to the invention, all of the stream (F) is generally recycled to the reactor. In the second and third methods of implementing the process, at least part of the stream (F) is used as liquid (L) in step (c) of the process. In this case, the balance of the stream (F) is generally recycled to the reactor.
In step (f) of the process according to the invention, the concentrated suspension (CS) is drawn off from the hydrocyclone separator. The concentrated suspension drawn off from the hydrocyclone separator comprises polymer particles and diluent.
In step (g) of the process according to the invention, the olefin polymer particles are separated from the concentrated suspension (CS). This separation may be carried out by any known method. The polymer particles are generally separated from most of the diluent by subjecting the concentrated suspension (CS) coming from step (f) of the process according to the invention to a treatment under temperature and pressure conditions suitable for vaporizing at least some of the diluent. The polymer particles now containing only a small amount of residual diluent can then be dried by any known means, for example by heating them in a dryer.
According to a first alternative version of step (g) of the process according to the invention, the pressure on the concentrated suspension (CS) is relieved to a pressure of less than 5xc2x7105 Pa. The vaporized diluent can then be recondensed by compression for the purpose of reusing it in the process according to the invention. Before it is reused, the diluent is normally purified so as to remove most of the olefin and possibly the other compounds present. After purification, the diluent can be reused in steps (a) and/or (c) of the process according to the invention.
According to a second alternative version of step (g) of the process according to the invention, the pressure on the concentrated suspension (CS) is relieved under temperature and pressure conditions which ensure that most of the diluent vaporizes, but which are such that the subsequent cooling of the vaporized diluent to a temperature of less than or equal to 60xc2x0 C. allows it to be recondensed without any compression. The temperature at which the pressure relief is carried out is generally between 50 and 90xc2x0 C. In order to adjust the temperature at which the pressure relief is carried out, it may be advantageous to heat the concentrated suspension coming from the hydrocyclone separator by means of a line heater. The pressure is generally reduced to between 5xc2x7105 and 20xc2x7105 Pa. This alternative version of the process has the advantage that the diluent thus separated from the polymer particles can be recondensed simply by cooling, without any compression step, and can be reused in step (a) of the process according to the invention. This second alternative version of step (g) of the process is highly advantageous when a diluent is used which has a boiling point at atmospheric pressure of less than about 25xc2x0 C.
The process according to the invention furthermore has the advantage that it makes it possible to obtain polymers having a narrower particle size distribution and greater homogeneity in their rheological properties.
The invention also relates to a plant used for carrying out the process described above, comprising a continuously operating polymerization reactor, a device used for adding liquid (L), a hydrocyclone separator, a device for drawing off the concentrated suspension (CS), a circuit for recycling the stream (F) to the reactor, and a device used for separating the olefin polymer particles from the concentrated suspension (CS).
As polymerization reactor, it is possible to use any continuously operating reactor, such as reactors of the stirred-vessel type or reactors of the loop type. Good results have been obtained with loop reactors.
In the process according to the invention, the stream (F) may be drawn off from the hydrocyclone separator and recycled to the reactor by benefiting from a pressure difference obtaining in the polymerization reactor. More particularly, when the polymerization reactor is a reactor of the loop type, the suspension (S) may be drawn off from the reactor and the stream (F) may be recycled to the reactor by benefiting from the pressure difference obtaining downstream and upstream of the system for stirring the loop reactor. However, it is preferred to draw off the stream (F) from the hydrocyclone separator by creating a pressure difference upstream and downstream of the hydrocyclone separator by means of a circulating pump. The pump is preferably mounted in the circuit for recycling the stream (F) to the reactor.

Solvay Polyolefins Europe-Belgium (Societe Anonyme)


A shifter assembly is disclosed for use with a manually-operated multiple-speed ratio transmission. The shifter assembly includes a tower housing fixed to the transmission casing, and a shift lever operably coupled to the gearshift mechanism housed within the transmission casing and which is supported for movement within the housing under the control of a vehicle operator. A shift inhibitor device is located within the housing and is operable for inhibiting movement of the shift lever from the highest forward gear position into the reverse gear position. In addition, the shift inhibitor device is also adapted to guide the shift lever into a "Neutral" position.

The present invention relates generally to gearshift mechanisms for use in manual transmissions and, more particularly, to a shift inhibitor apparatus that is integrated into the shifter assembly for preventing a vehicle operator from shifting into the reverse gear position in certain circumstances.
As is known, conventional manual transmissions are typically equipped with a shifter assembly for permitting a vehicle operator to selectively shift between various forward ratio gears and a reverse gear. The shifter assembly includes a tower housing secured to an exterior surface of the transmission casing and a shift lever that is operably coupled to a gearshift mechanism located within the transmission casing. Typically, the gearshift mechanism has a standardized shift pattern such that the shift lever is linearly movable along a "Neutral" path to a plurality of preselected "gate" position, each of which defining a shift plane for a pair of the ratio gears. Most commonly, a gate position located at one end of the Neutral path defines the shift plane between the highest forward ratio gear position (i.e., 5th gear) and the reverse gear position. To prevent the vehicle operator from inadvertently down-shifting along this shift plane from the highest forward gear position into the reverse gear position, it is known to "block" such a shift by installing a shift inhibitor device in conjunction with the gearshift mechanism.
One example of a shift inhibitor device of the type installed within the manual transmission and in relatively close proximity to the gearshift mechanism is shown in U.S. Pat. No. 4,738,153 to Sabel. Alternatively, it is known to mount a shift inhibitor device to an exterior surface of the transmission casing, such arrangements being shown in U.S. Pat. No. 4,638,678 to Gorman and U.S. Pat. No. 5,101,680 to Parsons. However, each of the afore-noted shift inhibitors can not be readily installed on existing or otherwise standard manual transmissions without requiring costly redesign and rework.
While conventional shift inhibitors perform satisfactorily, the need exists to develop a shift inhibitor that can be easily adapted for application to virtually any existing high-volume manual transmission.

Manual transmission shifter assembly with reverse inhibitor


Disclosed is a process for the production of d-mannose from fermented palm oil kernel meal using a continuous SMB separation process. The process is useful for providing a simplified processing route to providing high purity d-mannose. The SMB process and the SMB cycle was operated to provide a high purity mannose stream comprising d-mannose, salts, and color agents, a primary raffinate comprising glucose, other sugars and salts, and a secondary raffinate consisting essentially of the mobile phase desorbent. In the SMB cycle, the secondary raffinate was recycled to the SMB process as the mobile phase desorbent without further desalination. The highly pure mannose stream was further treated to remove color agents and salts prior to subsequent steps of precipitation or crystallization and drying. D-mannose is useful as a food additive, as a sweetener, as a texturizer, as a stabilizer, or as a humectant.

D-mannose is a sugar monomer of the aldohexose series of carbohydrates. D-mannose is a C-2 epimer of glucose, and has the following structure:

D-mannose is important in human metabolism, especially in the glycosylation of certain proteins.
The Palm kernel is the edible fruit of the oil palm tree. It yields two distinct oils—palm oil and palm kernel oil. The pulp left after oil is rendered is formed into "palm kernel cake", and is typically used either as high-protein feed for dairy cattle or burned in boilers to generate electricity for palm oil mills. A byproduct which is produced in conjunction with the production of palm oil is palm kernel cake (PKC), which is sometimes referred to as either palm kernel meal (PKM) or palm kernel expeller (PKE) depending upon the method employed in the extraction of the oil from the palm kernel. The process for producing the palm kernel cake is described in an article by Tang Thin Sue, entitled, "Quality and Characteristics of Malaysian Palm Kernel Cakes/Expellers." In general, the PKE byproduct is produced by a screw-pressing and filtration process, rather than a higher cost solvent extraction process.
The PKC or PKE contains a moderate level of crude protein (14.5 to 19.6 percent), but a high level of fiber (13-20 percent) and a poor amino acid profile which is deficient in lysine, methionine and tryptophan, and as such is considered a moderate quality food for ruminant mammals (having two-stomachs, such as cows) and not suitable for monogastric animals. The fiber of the PKE is primarily hemicelluloses consisting of mannans, moderate amounts of cellulose and small amounts of polysaccharides. The mannan portion of the PKE can range from between 25 to 32 percent. Because the mannan is hard and water insoluble and has a complex chemical structure, a combination of enzymes including mannosidases, galactosidases, glucosidases, and xylanases are required to release the potential fermentable sugars to improve the nutritive value of PKE to be of use to monogastric animals. Enzyme treatment of PKE for the improvement of the nutritive value of PKE is further described in an article by Saenphoom, et al., entitled, "Effect of enzyme treatment on Chemical composition and production of Reducing Sugars in Palm (Elaeis guineenis) Kernel Expeller."
U.S. Pat. No. 6,896,918 discloses a mannose containing palm kernel meal can be obtained by reacting a mannan degrading enzyme or an acid catalyst with palm kernel meal. A mixture of palm kernel meal, a mannan degrading enzyme and water thus prepared is reacted at the optimal temperature for the enzymatic activity to effect the reaction, and a wet composition is obtained. Mannose or mannosides (mannobiose, mannotriose, and mannooligosaccharides) are generated with the amounts depending on the reaction time in the wet composition. When the reaction time is between 24 to 72 hours, up to about 10-25 parts by weight of mannose are produced per 100 parts by weight of the material palm kernel meal, depending upon the amount of enzyme used. The resulting wet product, without further water removal, can be used as a feedstuff additive for preventing Salmonella infection. The palm kernel meal after the enzyme reaction contains considerable amount of water and the development of mold and fungi can occur during distribution and use, if untreated. In which case, the wet palm kernel meal may be dried to a water content of equal to or less than 10% by methods such as fluidized-bed drying or the like. Further, when highly purified mannose is required as materials for fine chemicals, it may be extracted and purified with an adequate catalyst such as water etc.
Simulation of a moving sorbent bed is described in U.S. Pat. No. 2,985,589 (Broughton et al.), which is mentioned above. In accomplishing this simulation, it is necessary to connect a feedstream to a series of beds in sequence, first to bed no. 1, then to bed no. 2, and so forth for numerous beds, the number of beds often being between 12 and 24. These beds may be considered to be portions of a single large bed whose movement is simulated. Each time the feedstream destination is changed, it is also necessary to change the destinations (or origins) of at least three other streams, which may be streams entering the beds, such as the feedstream, or leaving the beds. The moving bed simulation may be imply described as dividing the bed into series of fixed beds and moving the points of introducing and withdrawing liquid streams past the series of fixed beds instead of moving the beds past the introduction and withdrawal points. A rotary valve used in the Broughton process may be described as accomplishing the simultaneous interconnection of two separate groups of conduits.
U.S. Pat. No. 4,412,866 describes an example of the operation of chromatographic simulated moving bed (or sometimes called "SMB") method to separate the components of a feed stock. A resin bed is divided into a series of discrete vessels, each of which functions as a zone within a circulation loop. A manifold system connects the vessels and directs, in appropriate sequence to (or from) each vessel, each of the four media accommodated by the process. Those media are generally referred to as feed stock, eluent, extract and raffinate, respectively. As applied to a sugar factory, a typical feed stock is a lower purity sucrose solution, the eluent is water, the extract is an aqueous solution of sucrose and the raffinate is an aqueous solution containing non-sucrose, such as salts and high molecular weight compounds. The simulated moving bed disclosed by the '866 patent is of the type sometimes referred to as a "continuous SMB."
An example of a batch chromatographic method for the purification of sucrose is described in the disclosure of U.S. Pat. No. 4,359,430, which utilizes sucrose feedstocks derived from sugar beets at purities of approximately 7% to 60% sucrose. See also, e.g., U.S. Pat. No. 5,466,294, which utilizes a "soft raw syrup" as a feedstock to a chromatographic method which is not in a high purity form at a less than 89% purity sucrose on a dry solids basis, i.e., approximately 11% non-sucrose impurities.
US Patent Publication US2003/0222021 discloses a chromatographic separation process for recovering mannose with high purity using a chromatographic separation including a resin which is at least partially in a Ba2+ form resin and a resin which is other than Ba2+ form.
Methods are sought for a more efficient method of producing d-mannose from palm kernel meal.

Mannose production from palm kernel meal using simulated moving bed separation


The present invention provide a motion detection circuit for a handheld item detection system, where the motion detection circuit includes an accelerometer outputting at least one signal corresponding to a measured acceleration. A differentiator differentiates the measured acceleration. A motion detection device evaluates a discriminated version of the acceleration and a discriminated version of the acceleration to determine whether the handheld item detection system is in motion. The present invention extends battery life and allows a handheld system to quickly enter an active operational mode without any user intervention other than handling (moving) the system.

Handheld EAS and RFID/UPC data capture systems are used to scan items for EAS and RFID tags in a manner that allows the user to scan the item by pointing the handheld system at the item such as may occur at a checkout station in a retail environment or when taking inventory. This is particularly useful when the item to be scanned is large or when there are multiple items on a shelf or storage unit to be scanned. These handheld systems often operate wirelessly and include batteries to allow untethered operation.
Because the handheld EAS/RFID/UPC systems include batteries, battery life is a concern. The use of large and heavy batteries having a large storage capacity presents a problem due to the handheld nature of the system. If the system is too heavy, it becomes uncomfortable to hold and unwieldy to operate. As such, the use of as small a battery as possible is typically the choice of system designers. In order to accommodate the small battery and conserve battery life, some handheld EAS/RFID/UPC systems implement a low power mode. In this mode, as many power consuming components are disabled or placed into "sleep" mode as possible. To bring the unit back to full function, an input must first be activated such as detecting the operation of a scan trigger by the user. However, the turn-on delay coupled with the fact that the user must take a proactive role in cancelling the low power mode makes operation of the handset complicated and wastes time. It is therefore desirable to have a handheld EAS/RFID/UPC system that quickly returns to full power operation without the requirement that a user take a specific action, such as depressing the trigger, entering a command, depressing a button, etc.
In addition, handheld EAS/RFID/UPC data capture systems are prone to physical abuse such as dropping, banging, etc. Such is the case because these systems are typically heavily used by persons who may not feel the need to exercise care and caution when operating the system. For example, a low level checkout clerk may not treat the system as he would his own personal possessions. This can create problem in EAS environments where it is not uncommon for internal EAS data capture system voltages to approach and exceed 100 volts. If the system is dropped, there is currently no way for the user or a subsequent user to be made aware that the structural integrity of the system should be checked to make sure its continued operation does not present a safety issue.
Rather than alerting a user to check the system, current implementations try to protect the structural integrity of the system so that it is not damaged when abused, dropped, etc. Over-designing the mechanical structure to add strength is one approach. However, this solution is costly in terms of weight and therefore ergonomics for a handheld product. Over-designing also unnecessarily adds costs. It is therefore desirable to have a handheld RFID/EAS/RFID system that can alert users that the system has been dropped, banged, etc., and that it should be checked for damage.

Handheld data capture system with power and safety monitor and method therefore


A drug delivery device that includes a housing. The housing contains a syringe, and the syringe includes a container containing a liquid medicament. The container includes an aperture at a distal end and through which the liquid medicament can be dispensed. The syringe includes a stopper within the container. The stopper is moveable between a first longitudinal position and a second longitudinal position relative to the container, to cause dispensing of the liquid medicament through the aperture. The syringe includes at least one identifying means identifying the liquid medicament.

Current therapies delivered by means of self-administered injections include drugs for diabetes (both insulin and new GLP-A class drugs), migraine, hormone therapies, anticoagulants etc. Drug delivery devices such as auto-injectors aim to make self-administration of injected therapies easier for users. Auto-injectors are devices which completely or partially replace activities involved in medicament delivery of manual devices.
Some auto-injectors operate with a pre-filled cartridge or syringe system. This type of system is typically provided with a separate cartridge or syringe pre-filled with medicament. In some instances, the user must insert a pre-filled cartridge into the housing of the auto-injector before injection.
Auto-injectors may also be provided with pre-filled syringes already contained within their housing such that the user does not have the inconvenience of inserting the pre-filled syringe themselves. In this case, a pre-filled syringe is inserted into the auto-injector during assembly of said auto-injector.
During the manufacturing process of pre-filled auto-injector syringes, identical syringe packages are used for different liquid medicaments. This keeps manufacturing costs low and production efficiency high. The pre-filled syringes are inserted into auto-injectors by automated machinery.


Provided herein are polishing pads in which microcapsules that include a polymer material and are dispersed, as well as methods of making and using the same. Such microcapsules are configured to break open (e.g., when the polishing pad is damaged during the dressing process), which releases the polymer material. When contacted with ultraviolet light the polymer material at least partially cures, healing the damage to the polishing pad. Such polishing pads have a longer lifetime and a more stable remove rate when compared to standard polishing pads.

Chemical Mechanical Polishing (CMP) is a common practice in the formation of integrated circuits. Typically, CMP is used for the planarization of semiconductor wafers. CMP takes advantage of the combined effect of both physical and chemical forces for the polishing of wafers. It is performed by applying a load force to the back of a wafer while the wafer rests on a polishing pad. A polishing pad is placed against the wafer. The polishing pad and the wafer are then counter-rotated while a slurry containing abrasives and/or reactive chemicals is passed therebetween. CMP is an effective way to achieve global planarization of wafers.

Taiwan Semiconductor Manufacturing Co., Ltd.


An arithmetic and control unit is configured to calculate a resistance value of a glow plug on the basis of an energization current of the glow plug and a voltage applied to the glow plug, perform a multiplication of the resistance value and a constant that has been determined beforehand on the basis of an electrical characteristic of the glow plug, input a predetermined heater reference point temperature, calculate an offset with a predetermined offset arithmetic expression from the heater reference point temperature, correct the multiplication result with that offset, and take the correction result as an estimated temperature of a tip of the glow plug.

The invention pertains to a method of estimating the temperature of the tip of a glow plug and particularly relates to the acquisition, by a simple method, of an estimated temperature of the tip of a glow plug used in an internal combustion engine or the like and an improvement in the precision thereof.
Conventionally, it has been well known that the temperature of the tip of a glow plug used in an internal combustion engine such as a diesel engine is an element that is important as a parameter for controlling the energized state of the glow plug itself.
For this reason, for example, various devices in which a thermocouple is built into the tip portion of the glow plug and which make the temperature of the tip portion directly acquirable and supply the temperature for engine control, and various methods of estimating the temperature of the tip of the glow plug from the resistance value of the glow plug at the time of energization, have been proposed, for example, in JP-A-2001-336468 and etc.
However, in the configuration described above where a thermocouple is disposed in the tip portion of the glow plug to detect the temperature of the tip portion, an adhesive secures the thermocouple, and there is no adhesive whose upper temperature limit is sufficient. In addition, the consistency between the coefficient of thermal expansion of the adhesive and the coefficient of thermal expansion of the thermocouple is not always good. So there are worries that the thermocouple will become disconnected or separate from the place to which it is adhered. And in addition to the problem that the configuration is less than perfect in terms of its solidness, there are also the problems that the configuration of the glow plug itself becomes complicated and expensive.
Further, in conventional methods of estimating the temperature of the tip of the glow plug from the resistance value of the glow plug, the heat transfer environment around the glow plug changes depending on the load and speed of the engine, which in no small way affects the resistance value of the glow plug. So there is the problem that the precision of estimation is not always sufficient.

Glow plug tip temperature estimating method and glow plug drive control device


An orthodontic appliance and system are provided for adjusting the relative positions of mandibular and maxillary arches. The orthodontic appliance includes a telescoping assembly including a plurality of telescoping members, and at least a first end member supportably retaining at least a portion of a spring member. The end member is adapted to slidably receive an end of a first telescoping member for selectively interconnection and disconnection therebetween. When interconnected, the spring member extends into an open end of the first telescoping member and is operative to apply spring-force to a second telescoping member. A plurality of interchangeable end members may be provided for use with the telescoping assembly, wherein the different end members have different spring-force delivery attributes. The orthodontic appliance may be installed utilizing an attachment device selectively interconnectable to and disconnectable from orthodontic archwires.

Orthodontic treatment involves the movement of malpositioned teeth to desired positions. During typical treatment, orthodontic brackets are connected to anterior, cuspid, molar, and bicuspid teeth, and an archwire is placed in a slot of each bracket. The archwire guides movement of the brackets and the corresponding teeth to desired positions to correct occlusion. Traditionally, the ends of an archwire have been anchored by appliances known as buccal tubes that are secured to molar teeth (e.g., utilizing bands). More recently, archwire ends are increasingly being secured utilizing buccal tubes bonded directly to molar teeth (e.g., free from use of buccal tubes welded to bands).
Various types of spring devices and elastomeric devices may also be used in orthodontic treatment. The resilient forces of such devices in tension or compression may be used to secure an orthodontic appliance and an interconnected tooth or teeth and correspondingly facilitate movement relative to other orthodontic appliances and an interconnected tooth or teeth. For example, elastomeric rings may be employed as ligatures to secure an archwire in a slot of a bracket. As another example, elongated elastomeric devices (e.g., a chain of interconnected elastomeric ligatures) may be stretched between selected brackets in order to move certain teeth relative to other teeth. Yet other spring devices may be specifically designed to separate adjacent teeth or to rotate a tooth about its long axis.
The orthodontic treatment of some patients includes correction of the alignment of the maxillary dental arch and the mandibular dental arch. For example, certain patients have a condition referred to as a Class II malocclusion wherein the lower dental arch is located an excessive distance rearward of the upper dental arch when the jaws are closed. Other patients may have an opposite condition referred to as a Class III malocclusion wherein the lower dental arch is located forward of the upper dental arch when the jaws are closed.
Orthodontic treatment of Class II and Class III malocclusions typically entails movement of the maxillary dental arch (e.g., teeth comprising the maxillary arch) and/or movement of the mandibular dental arch (e.g., teeth comprising the mandibular arch). For such purposes, an activation force is often applied to teeth of each dental arch by applying a spring force to brackets, archwires or attachments connected to the brackets or archwires. In this manner, the Class II or Class III malocclusion can be corrected as the archwires and brackets are used to move individual teeth to desired positions.
As with all orthodontic treatment regimes, there is a continued focus on addressing Class II and Class III malocclusions in not only a therapeutically effective manner, but also in a manner that yields treatment and orthodontic practice efficiencies. In the latter regard, orthodontic appliances that may be readily installed, adjusted, replaced and removed yield numerous advantages.


A system to manage utilization of a plurality of types of assets by a plurality of independent entities is provided. The system comprises a controller including a processor operable to execute a plurality of program instructions generally representative of the steps of receiving a plurality of parameters from each of the plurality of independent entities; segmenting the plurality the independent entities into more than one cluster dependent on identified similarities in at least one of the plurality of parameters of the one or more of the plurality of entities; and generating a display of a comparison of the plurality of parameters of each of the independent entities relative to another in each of the plurality of clusters.

This invention generally relates to a system for and method of managing purchases, and more particularly, to a system and method to predict or forecast needs to purchase or rent assets to track and limit movement of the at least one asset.
Larger industrial, healthcare or commercial facilities can be spread out over a large campus and include multiple floors each having multiple rooms. Each of the facilities can employ various assets used in manufacturing or providing services. For example, a healthcare facility or hospital employs numerous assets that can be spread out over a large campus and/or moved from room to room. Examples of assets include intravenous pumps, wheel chairs, digital thermometers, local patient monitors, etc. A similar scenario can be said for an industrial facility that includes various portable pumps, hoists, winches, etc.
Facilities typically acquire or purchase assets on a purely speculative basis. There is a need for a system to improve efficiency in the purchase of assets on a per department basis that does not rely on mere speculation. There is also a need for a system that includes architecture to manage assets from a prediction of need phase to a retirement or disposal phase of the asset.

System and method to manage assets of healthcare facility


Vehicle seat which effects a sideways movement of the occupant sitting on the vehicle seat during a lateral impact or directly before a lateral impact. The sideways movement takes place away from the side of the vehicle which faces the impact and toward the center of the vehicle, at least one seat cushion being transversely displaceable separately in relation to the seat components and in relation to the seat fixing elements for the sideways movement.

The invention relates to a vehicle seat which effects a relative movement of the occupant sitting on it away from a side of the vehicle which faces a lateral impact toward a center of the vehicle during or immediately debore the lateral impact and to a method for controlling the vehicle seat.
DE 3023035 A1, which forms the generic type, discloses a vehicle seat which is suitable for considerably reducing the load on the occupant during a lateral impact. The seat comprises a seat bracket which permits a transverse movement of the seat relative to the seat mount in the vehicle during a lateral impact. The transverse movement can take place by means of a transverse displacement drive, with the result that, if a collision object intrudes into the vehicle, the vehicle occupant undergoes a relative movement away from the intrusion site and toward the center of the vehicle by the transverse movement of the entire seat in the direction of action of the impact. The transverse movement of the seat can be controlled in such a manner that the displacement of the seat is initiated before the forces arising from the intrusion have an effect, the displacement forces and the moment of displacement being adapted to give an optimum protective action.
It is the object of the invention to specify a vehicle seat and a method for controlling the vehicle seat, with which an occupant can be protected to the greatest possible extent by virtue of his displacement during a lateral impact. This object is achieved in respect of the vehicle seat wherein at least one seat cushion can be displaced separately in relation to other seat components and seat fixing elements transversely with respect to the longitudinal axis of the vehicle and is achieved in respect of the method by transverse displacement of the seat cushion begins before the moment of collision.
The invention is based on a vehicle seat in a motor vehicle which effects a relative movement of the occupant sitting on it away from the side of the vehicle which faces the impact toward the center of the vehicle during a lateral impact. As an alternative to this, the lateral displacement of the vehicle occupant may also already be initiated before the moment of collision. According to the invention, in order to displace an occupant, rather than the vehicle seat being displaceable as a whole, an individual seat component, in particular a seat cushion, is displaceable transversely with respect to the longitudinal axis of the vehicle independently of the rest of the vehicle seat. It is self-evident that also a plurality of seat cushions may be individually laterally displaceable. It is an advantage of the invention that the mass which is to be accelerated is reduced, this making a smaller displacement unit possible which can be accelerated and braked more rapidly. The constructional space to be kept for the displacement is reduced, since other seat components, for example the seat frame, are not displaced. A further advantage is that a larger displacement distance for an occupant is made possible than is the case if the entire seat is displaced. An additional advantage of a vehicle seat according to the invention is that parts of the vehicle seat which are not displaced, for example a seat frame or a mechanism for displacing the seat longitudinally, can absorb additional deformation energy.

Vehicle seat and method for controlling the same


A printing apparatus, comprising a driving unit for driving a printhead including a plurality of nozzles each of which prints a dot, a conveying unit for conveying a printing medium, a memory and a unit, wherein the plurality of nozzles are arranged to form nozzle arrays adjacent to each other, the unit performs a first operation for developing printing data column by column on the memory, a second operation for assigning the printing data to each nozzle array, and a third operation for controlling the driving unit based on the assigned printing data, and, after the first operation and before the second operation, the unit specifies a portion of the printing data corresponding to a dot deviated from a correct printing region due to a tilt of the nozzle arrays and rearranges the portion.

1. Field of the Invention
The present invention relates to a printing apparatus and a method of processing printing data.
2. Description of the Related Art
A printing apparatus includes a printhead in which a plurality of nozzles (ink orifices) are arranged, and performs printing by alternately performing an operation of printing a dot by each nozzle while scanning the printhead on a printing medium, and an operation of conveying the printing medium. Dot printing is performed by driving printing elements formed in one-to-one correspondence with the nozzles. Note that the scanning direction of the printhead is called a "main scanning direction", the conveyance direction of the printing medium is called a "sub scanning direction", and the two directions intersect each other.
FIG. 31 is a schematic view exemplarily showing dots d printed on a printing medium P when printing is performed by a time-divisional driving method by using a printhead H. Note that the time-divisional driving method is a driving method of performing printing by dividing a plurality of printing elements corresponding to a plurality of nozzles nz into, for example, N groups G (G0 to GN-1), and sequentially driving the printing elements of each group G one by one. Note that printing elements to be driven at the same time in the groups G0 to GN-1 are classified as a "block", and 16 blocks B (B#0 to B#15) exist in the example shown in FIG. 31.
As shown in FIG. 31, an image based on printing data input to the printing apparatus is formed by a plurality of dots d printed in each column on the printing medium P. More specifically, the printing data input to the printing apparatus is first developed (expanded) so that a plurality of printing elements can be driven in a predetermined order. After that, each printing element is driven based on the developed printing data, and the nozzle nz corresponding to the printing element discharges ink (a printing agent), thereby printing the dot d for forming an image in a corresponding column on the printing medium P.
If the direction in which the plurality of nozzles nz are arranged has a tilt with respect to the sub scanning direction, this tilt produces a shift of a printing position (a shift from the intended position of the dot d). That is, the dot d to be printed in a given column is printed in a position (for example, an adjacent column) deviated from the given column due to the tilt. This will be explained with reference to FIG. 32.
FIG. 32 is a schematic view showing, in the same manner as in FIG. 31, a printhead H having a nozzle array whose arrangement direction has a tilt with respect to the sub scanning direction, and dots d printed when printing is performed by using the printhead H. For example, of the dots printed by nozzles nz of a group G2, two dots on the downstream side in the conveyance direction of a printing medium P are intended to be printed in column 0 but are printed on the left side of column 0 due to the tilt of the nozzle array. A shift of the printing position like this may decrease the image quality.
Japanese Patent Laid-Open No. 2009-6676 has disclosed a technique which, when the direction in which a nozzle array is arranged has a tilt with respect to the sub scanning direction, acquires the tilt amount based on a test pattern formed by the nozzle array, and corrects a shift of the printing position in accordance with the tilt amount. According to Japanese Patent Laid-Open No. 2009-6676, this correction is performed by changing, in accordance with the above-mentioned tilt amount, the read position of printing data stored in each address of a memory (storage means) in association with each column on a printing medium. Consequently, a dot is printed in an intended column instead of an adjacent column.
As a printing method advantageous in increasing the printing speed or improving the image quality, there is a method in which a printhead has two or more nozzle arrays which discharge ink of the same color, and printing is performed by using these nozzle arrays in order. For example, when the printhead has two nozzle arrays, dots adjacent to each other in the main scanning direction are printed by alternately using the two nozzle arrays. Japanese Patent Laid-Open No. 2009-6676 does not take account of a method of correcting a shift of the printing position in this printing method.

Printing apparatus and method of processing printing data


A case for displaying a collectable bat comprises a hollow tubular element formed by the longitudinal juncture of two semi-tubular elements and secured at both the top and bottom ends by identical end caps defining resilient concave surfaces for respectively engaging the opposite ends of a collectable bat inserted in the display tube.

The growth of collectors in the United States and other countries, and the number and types of items collected has shown remarkable increase over the past 20 years. One such item that has experienced substantial growth is collectable bats, i.e., bats that are famous because of the fame of the person that used the bat, or because the bat was instrumental in winning a particular ball game or World Series.
Very substantial prices have to be paid for such bats by the ardent collectors and it is always their desire to display their collection of bats, but in a manner that does not permit the deterioration of the surface of the bat by handling, or by repeated insertion or removal from a display holding device. A problem arises when a transparent, elongated container is employed to house a collectable bat in that the container should most desirably permit the insertion of the bat with either end of the bat in the upright position.
Additionally, while it is a fairly easy task to keep the exterior of the transparent container clean to maximize the visibility of the collectable bat, it is very difficult, if not impossible, to effect the proper cleaning of the internal surface of the display container. Thus, an improved transparent readily cleanable container for displaying collectable bats represents an item long needed by bat collectors.

Display container for collectable baseball bats


Provided is an electrophotographic member conducive to the formation of a high-quality electrophotographic image, the member showing a small increase in resistance even after long-term electrification under a high-temperature and high-humidity environment, and a process cartridge and an electrophotographic apparatus each including the electrophotographic member as a charging member and/or a developer carrying member. Specifically, provided is an electrophotographic member including a substrate and an electro-conductive layer, in which the electro-conductive layer contains a resin having a structure unit represented by the following structural formula (1) and a specific anion:

Field of the Invention
The present invention relates to an electrophotographic member to be used in an electrophotographic apparatus, and a process cartridge and an electrophotographic apparatus each including the electrophotographic member.
Description of the Related Art
In an electrophotographic apparatus (such as a copying machine, facsimile, or printer employing an electrophotographic system), an electrophotographic photosensitive member (hereinafter sometimes referred to as "photosensitive member") is charged by a charging member and exposed by a laser or the like, and as a result, an electrostatic latent image is formed on the photosensitive member. Next, toner in a developer container is applied onto a developer carrying member by a toner-supplying roller and a toner-regulating member. The electrostatic latent image on the photosensitive member is developed with the toner conveyed to a developing region by the developer carrying member at a portion in which the photosensitive member and the developer carrying member are in contact with, or close to, each other. After that, the toner on the photosensitive member is transferred onto recording paper by a transfer unit, and is fixed by heat and a pressure. In addition, the toner remaining on the photosensitive member is removed by a cleaning blade.
In the electrophotographic apparatus as an image-forming apparatus adopting the electrophotographic system, an electro-conductive member has been used in various applications, e.g., electro-conductive rollers such as a charging roller, a developing roller, and a transfer roller. The electrical resistance value of any such electro-conductive roller is controlled to from 105Ω to 109Ω. In addition, an electro-conductive layer having added thereto an ionic electro-conductive agent such as a quaternary ammonium salt compound is provided for the adjustment of any such roller to such electro-conductivity.
An ionic electro-conductive member obtained by adding the ionic electro-conductive agent can reduce the non-uniformity of the electrical resistance value resulting from non-uniform dispersion of the electro-conductive agent as compared to an electronic electro-conductive member. Accordingly, a low-resistance site hardly occurs in the electro-conductive layer in a local manner.
Meanwhile, the ionic electro-conductive agent such as a quaternary ammonium salt or an alkali metal salt may bleed to the surface of an electro-conductive roller (hereinafter referred to as "bleeding"). As a result, a change in outer diameter dimension of the electro-conductive roller, an increase in property by which dirt adheres to the surface of the electro-conductive roller, and the contamination of the surface of any other member to be brought into contact with the electro-conductive roller may occur. In addition, a desired resistance value may not be obtained under a high-temperature and high-humidity environment or a low-temperature and low-humidity environment because the resistance of the roller is liable to fluctuate depending on an environment.
Japanese Patent No. 4193193 discloses a method involving using an ionic liquid having a specific chemical structure as a method for the suppression of the bleeding of the ionic electro-conductive agent and the suppression of the fluctuation in resistance with an environment. In addition, Japanese Patent No. 4392745 discloses a method involving using an ionic liquid having specific physical properties.

Electrophotographic member, process cartridge, and electrophotographic apparatus

Abstract: in the structural formula (1), R1 represents a hydrogen atom or a methyl group, and Z represents a cationic organic group.


The present invention relates to a versatile side-on type photomultiplier comprising a structure for improving the uniformity in light receiving sensitivity. Disposed on the outer peripheral surface of a sealed envelope of this photomultiplier is a restricting member which guides light to be detected into, of the light receiving surface of a photocathode, an effective region where the light receiving sensitivity is high, thereby restraining the light to be detected from reaching the outside of the effective region.

1. Field of the Invention
The present invention relates to a light detecting apparatus for detecting light incident thereon and, in particular, side-on type photomultiplier having a photocathode which is inclined with respect to the direction of incidence of the light.
2. Related Background Art
For instance, Japanese Patent Publication No. 2-22334 discloses an example of side-on type photomultipliers. In the photomultiplier disclosed in this publication, light passing through a slit is guided through an imaging lens onto a reflection type photocathode. Such a configuration shortens the electron transit time between the photocathode and the dynode of the first stage, thereby reducing the fluctuation in electron transit time.


A wavelength locker operates with a reference tunable liquid crystal filter having integrated photodetectors deposited on the front and backside of the liquid crystal cell to track power intensity of the accepted passband signal and its rejected signal compliment at a 50% power point where the two signals cross on the side of the filter transmission peak. The tunable filter is tuned by an offset wavelength from the laser wavelength such that 50% power is transmitted through the filter at the center wavelength of the laser. The wavelength locker may be configured with a liquid crystal tunable etalon or a liquid crystal tunable bandpass filter. A method for locking an optical signal to a desired frequency is also included and provides a substantially linear feedback signal computed by dividing the rejected signal power by the accepted signal power and passing it to laser transmitter to enable it to correct for frequency drift. Optional features of the present invention include an integrated thermal sensor and heater and temperature compensation control schemes.

Laser frequency locking is an essential technology for optical communications and other fields. In telecommunications, Dense Wavelength Division Multiplexing (DWDM) systems require tight control and accurate tuning of each frequency propagated down an optical fiber by a communication laser. In DWDM, each of a plurality of laser signal sources is tuned in frequency to a distinct channel, allowing a plurality of signals to be simultaneously transmitted down a single optical fiber. In this way, large volumes of information can be transmitted through a single optical fiber. The communication channels are defined on a grid with equal frequency spacing in a band range approximately between 188-197 THz (the ITU grids).
Each laser must be stabilized, or "locked" to ensure it remains frequency-tuned to the proper communications channel. Frequency locking techniques must withstand environmental or systematic disturbances. A wavelength locker provides a stable and calibrated reference for measuring the wavelength deviation of a laser output from a desired wavelength. The signal from the wavelength locker is used to tune the laser wavelength back to the desired frequency. In a DWDM system, mistuning is highly detrimental to the performance of communications since DWDM components exhibit wavelength-dependent losses. In other systems, mistuning a laser can have various negative ramifications depending on the measurement, analysis or process facilitated by the laser. In telecommunications applications, wavelength lockers are critical because they allow for more closely spaced channels, thus increasing the information bandwidth of a DWDM system.
It is common to use a Fabry Perot etalon as a reference element in a wavelength locker. A Fabry Perot etalon is an interferometric device composed of 1 mm solid silica with partially-reflecting mirrored sides that are substantially parallel. A light beam passing through an etalon is expressed as an Airy function and the separation in frequency between the period peaks of the transmission response is called the Free Spectral Range ("FSR"). The FSR is defined by the optical path length of the gap between the etalon mirrors. Typically, a wavelength locker based on a Fabry Perot etalon will be designed so that the FSR of the etalon is matched against the frequency spacing of the ITU grid so that the etalon provides a calibrated reference to indicated the frequency location of the ITU channels.
Typically, frequency locking is performed in a feedback loop whereby the output of the laser is tapped and coupled to the wavelength locker which tracks the output from its etalon with a photodetector. The side of the etalon transmission peak is monitored for frequency discrimination against a reference value. The difference between the monitored transmission and the reference value is proportional to the deviation of the lasing frequency from the desired lock point. The difference then used as feedback into the laser control electronics, to adjust the lasing frequency to the desired lock point.
However, one known issue with the use of Fabry Perot etalon as a reference element in a wavelength locker is that power fluctuations in the input light are also capable of producing changes in the etalon transmission signal that mimic a frequency change, resulting in the potential to unintentionally detune the laser from the desired lock point. It is common to use a second photodetector to tap a power reference signal from the output of the laser to ensure that power fluctuations are differentiated between a frequency change. The power reference signal is used to normalize the etalon transmission signal to render it insensitive to changes in the input optical power.
Another known issue with the use of Fabry Perot etalon as a reference element in a wavelength locker is that temperature fluctuations to the etalon changes the optical path length of the etalon due to the material's thermal coefficient of expansion, thereby changing the FSR and peak locations of the Fabry Perot etalon and causing the laser to detune from the desired lock frequency. Thermally-induced changes to the etalon are normally mitigated by constructing the etalon from temperature-insensitive materials and mixing material stacks with offsetting coefficient thermal expansion (CTE) properties. However, the materials generally used to construct the etalon also exhibit a temperature-dependent refractive index. Often the only way to mitigate temperature fluctuations from impacting the performance of the device is to assemble and mount the etalon on a temperature controlled platform. The long lifetimes of telecommunications systems demand that wavelength lockers operate robustly over a very long period exceeding 20 years. Wavelength lockers most also be constructed to avoid the outgassing of superfluous material, to survive mechanical and thermal shock, and otherwise not age in an observable or detrimental way. Epoxies and adhesives used to assemble wavelocker systems are notorious for age-dependent power losses, outgassing, and inadvertent etalon effects.
In addition to the technical requirements of a wavelength locker device, the telecommunications market demands that wavelength lockers are physically no greater than 33 mm3 and small enough to fit inside a 14-pin butterfly package along with the packaged laser. In addition, the telecommunications market demands that wavelockers exhibit a long lifetime and are inexpensive.
Finally, existing wavelockers are generally fixed and therefore require active alignment to match the 50% point exactly. Also, since each filter is optimized for a single wavelength, laser manufacturers are forced to stock an abundance of parts each having a frequency that matches the wavelength of the various lasers the offer.
As so, there is a need for a wavelength locker that has a small physical size. There is also a need for a wavelength locker with a size suitable for placement inside an associated laser package. There is a further need for a wavelength locker that operates robustly over a very long lifetime. Yet another need for a wavelength locker that does not use epoxies and adhesives in the beam path.

Wavelength locker with liquid crystal tunable filter generating transmitted and reflected outputs


An improved technique involves providing a naming scheme that uses a unique numeric identifier associated with a particular naming protocol. Along these lines, when a storage processor receives a first name of a file that conforms to a first naming protocol, the storage processor places the first name and an inode number corresponding to the file in a directory entry. The storage processor associates this entry with a unique numeric identifier by which the entry can be located within the directory. Based on this unique identifier, the storage processor is configured to generate the second name that conforms to the second naming protocol.

Some filenames satisfy particular naming protocols. For example, suppose that a user on a computer running a Unix® operating system accesses a particular text file by referring to the string "root/user/TextFileInTheUserDirectory.txt". In this case, the filename "TextFileInTheUserDirectory.txt" satisfies a Unix naming protocol that requires, for example, a 255-byte limit to filename length with case sensitivity. Other naming protocols include the Microsoft® Windows, or M256, naming protocol having a limit of 255 case insensitive Unicode characters in filename length with a list of reserved characters, and the DOS, or M83, naming protocol having a filename limit of twelve case-insensitive characters, with 8 characters for a base name, 3 characters reserved for an extension, and a "." separating the base name and the extension. (In other words, a DOS filename takes the form "xxxxxxxx.yyy," where the x's and y's represent ASCII characters.)
Some directories are multiprotocol in that they support multiple naming protocols. That is, a multiprotocol directory supports access to a single file by users on computers running different operating systems, each of which supports different naming protocols. For example, a first user on a computer running Unix and a second user on a computer running Windows may both be able to access the single file. Along these lines, the directory maps each of these filenames to the same inode number.
In response to the naming of a file in one naming protocol, a file system containing a multiprotocol directory may create equivalent filenames in each of the other naming protocols it supports. Along these lines, suppose that a user creates the following filename for a file on a computer running Windows: "TextFileInTheUserDirectory.txt". The computer would then translate this name into, say, Unix and DOS according to the rules governing the respective naming protocols. In a conventional naming process, the conversion from a longer M256 or Unix filename to a shorter M83 filename involves truncating the longer filename to at most eight characters, such as in "TEXTFI˜1.TXT". Other rules govern M256 filenames that have characters reserved in DOS.

Implied M83 names in alternate name generation in directories supporting multiple naming protocols


A precast stackable tower shaft wall stair unit and method having four structurally interconnected opposing walls forming a peripherally defined body defining a medial channel extending therethrough. A locking recess is defined in one corner portion at adjacent interconnected walls, and a mating locking protuberance is carried at a diametrically and vertically opposite corner portion allowing units to be stacked upon one another forming a continuous medial channel extending therethrough. A lower landing, an upper landing and a flight of stairs extending between a lower landing and an upper landing are carried on a wall in the medial channel extending from the lower edge to an upper edge. Stacking of adjacent to units simultaneously forms a medial channel extending therethrough and a continuous stairway therein.

1. Field of Invention
The present invention relates to towers, shafts and stairways. More particularly, the present invention relates to precast stackable concrete bodies, each precast body having four structurally interconnected walls defining a medial channel extending therethrough, the precast bodies are stackable vertically to provide a tower and/or shaft having a continuous medial channel extending therethrough and a continuous flight of stairs extending through the medial channel of the tower and/or shaft.
2. Background
Many construction projects including, but not limited, to mining, pumping stations, cooling towers, underwater construction, underground geothermal installations, and above ground access chambers whether of new construction or retro-fit/remodeling have a need for vertical shafts for elevators, stairs and/or service equipment such as communication, plumbing and electrical. Regulations and building codes for such shaft structures are replete with requirements for safety, access, and ingress and egress redundancy.
It is known in the construction industry for shafts and towers to be either "cast in place" or formed using "precast planar wall panels" that are attached to one another "in-situ" to form the shaft.
Generally, towers and shafts for elevators, stairs, service equipment, and the like are formed by establishing a supporting foundation at the lowest level, and then constructing the shaft/tower vertically upwardly from the foundation which may be at ground level, below ground level or above ground level. For purposes of this disclosure, the method is described for constructing a shaft below grade (i.e. below ground level) but the process for constructing a tower (above grade) is similar except that the components are hoisted vertically upwardly to be placed upon an uppermost level as opposed to lowered into a shaft to connect with a previously positioned level.
When the "cast in place" method is used, a shaft is excavated in the ground and movable, spaced apart forms are positioned to form an inside surface of a shaft/tower wall and at a position to form an outside/exterior surface of the shaft/tower wall. Reinforcing elements such as steel, and/or rebar may be added to the space between the two forms and concrete is then poured into the space defined between the forms and about the reinforcing elements. As the concrete at the lowest levels cures/hardens, the forms are moved and repositioned upwardly and more reinforcing is added and more concrete is poured. The process is repeated/continued until the desired uppermost level is formed. This "cast in place" method is complex, dangerous and time consuming, especially when a below grade shaft is being formed because a shaft requires workers to be within the shaft to position and move the forms, install the reinforcing, pour the concrete, and all of the construction materials must be lowered down the shaft from above while the workers are within the shaft. After the shaft/tower is complete, stairs may be added to interior shaft walls by attaching fastening means to the interior shaft walls and thereafter attaching stringers/flights of stairs to the fastening means after lowering the stringers/flights of stairs down the shaft from above.
When the pre-cast planar wall panel method/process is used to construct a below grade shaft, the pre-cast planar wall panels are hoisted with a crane and lowered into the shaft and positioned one at a time upon a foundation and fastened thereto. Thereafter, additional pre-cast planar wall panels are fastened to the previously installed pre-cast wall panels along adjacent edge portions. This method is also complex, dangerous and time consuming because it requires workers to be within the shaft to position and align the pre-cast planar wall panels, to support the pre-cast wall panels while the level is completed, to interconnect the panels together, to caulk or otherwise seal the joints between the adjacent panels and all of the construction materials must be lowered down the shaft from above while the workers are within the shaft. Each of the pre-cast planar wall panels generally carries at least one weld-plate at each end portion and at top and bottom portions that are positioned immediately adjacent similar weld-plates carried by immediately adjacent pre-cast wall panels when the wall panel is properly positioned. The weld-plates are "welded" together to provide additional strength and integrity between the adjacent wall panels. Unfortunately the welding of weld plates may require workers to access both the interior and exterior portions of the pre-cast planar panels within the shaft. The weld plates also add complexity to the pre-casting of the planar wall panels as the weld plates must be correctly positioned within the forms prior to the concrete being poured into the forms, and the "bonding" of metal to concrete can be problematic as such interfaces are subject to corrosion, chemical reactions and the like that can, over time, weaken the concrete proximate to the metal weld plate and/or weaken the metal comprising the weld plate and/or weaken the weld interconnecting the adjacent weld plates.
Such known methods for forming towers and shafts are complex, dangerous to workers, expensive and time consuming. In the situations where a shaft is being constructed below grade, "shoring" and support must be installed and maintained throughout the length of the shaft for the duration of the project to prevent collapse of the surrounding earth defining the shaft. There may also be a need for a temporary elevator or lift for workers to reach the work site inside the shaft such as to move the forms and weld the weld-plates to one another. After the shaft is complete, workers must seal/caulk the joints between the adjacent panels and install flights of stairs within the shaft by attaching fasteners to inside walls of the shaft at specified locations, and thereafter attaching stringers of stairs to the fasteners which are lowered down the shaft from above. This work is hazardous as the flights of stairs must be lowered down the shaft from above while the workers are within the shaft. Further yet, when the shaft to be constructed is below grade level, the "hole" in which the shaft is constructed needs to be significantly larger than the ultimate finished shaft size because of the need for workers to readily and safely access the exterior of the forms while the shaft wall is being built.
The instant invention overcomes various of the aforementioned drawbacks to known construction methods and apparatus for towers and shafts by providing a precast stackable peripherally defined unit having four structurally interconnected spaced apart tower/shaft walls defining a medial channel extending therethrough. Each stackable unit may carry a preinstalled flight of stairs within the channel defined by the walls. A locking protrusion and a locking recess defined in diametrically and vertically opposing top and bottom corners of each unit allows units to be stacked on top of one another providing a continuing staircase within the medial channel. Because each unit is integral, having four interconnected cooperating supporting walls the thickness of the walls may be reduced while maintaining necessary strength and rigidity and reducing weight. Further, because the four walls are formed as a single unit there are no vertical seams that need to be caulked or otherwise sealed because as each unit is stacked in place that level is complete and useable by workers. Because each unit is similar, the concrete forms for casting the units are all the same. Horizontal seams between immediately adjacent units carry a pre-installed pliable sealant such as, but not limited to butyl tape which provides a fluid tight seal between immediately adjacent units. Weight of the stacked units compresses the pliable sealant which may be applied to an upper and/or lower surface edge of each unit prior to installation further reducing labor costs and time.
Further still, because there is only a limited need for workers to physically access and work on the exterior surface portions of the units during installation, the shaft may be smaller further reducing time and associated costs. Because the flights of stairs may be preinstalled within the units as the units are stacked upon one another the stairway is also simultaneously constructed, eliminating the need for subsequent stair installation which even further reduces costs and installation time.
Some or all of the problems, difficulties and drawbacks identified above and other problems, difficulties, and drawbacks may be helped or solved by the inventions shown and described herein. The instant invention may also be used to address other problems, difficulties, and drawbacks not set out above or which are only understood or appreciated at a later time. The future may also bring to light currently unknown or unrecognized benefits which may be appreciated, or more fully appreciated, in the future associated with the novel inventions shown and described herein.

Stackable tower shaft wall stair unit and method


The present invention relates to an operating module for dynamically creating the user interface on the operating module for controlling and operating a machine of the food industry, in particular the beverage industry. The operating module comprises a plurality of operating elements having attributes, which can assume the value of a parameter and can be activated or deactivated depending on the user. By means of an operating module context, operating elements having certain attributes and values can be selected in order to be displayed on the operating module. The invention further relates to a method for dynamically creating and displaying an operating interface for operating a machine of the food industry.

Hence, there is an enormous increase in the scope and, consequently, in the complexity of such computer programs and operating modules, and a high navigation effort is required. Normally, a plant comprises eight or more machines of a manufacturer, which act as a plant via an exchange of signals and start and stop the production in a well-matched manner.
Complex plants, such as a production line for blow-molding, labeling, filling and closing of containers, may thus have several hundred pages of operating elements. For structuring the content of the operating pages, the classical, fixed menu concept comprising main menu items and 1−n subitems, into which the contents are fixedly incorporated, is normally chosen. A similar concept is the principle of a main button bar supplemented by a second button bar, e.g. tabs for subgroups for the respective main buttons. The fixed structure of a menu and the incorporation of the contents projects the mental model of the creator onto the system. The future user, however, often thinks differently and will have problems finding the contents and retrieving contents, since the approach is not logical from his point of view and, consequently, not reproducible. The situation will become even more problematic, if different groups of users with different experiences and different tasks must work with one and the same fixedly defined structure. Since the mental models are all different, it will be impossible to optimally support all of them by the menu structure. Eventually, a more or less satisfactory compromise will be made, or one group of users will deliberately be supported better than the others.
The navigation effort entailed by classical menu navigation is a safety-critical aspect. In order to be able to react quickly to production processes and events, it is important that a user will quickly find the appropriate operating elements and that the navigation time will be reduced to a minimum.

Operating module and methods for dynamic adapatation of a user interface for a machine


A process for the multi-layer coating of electrically conductive substrates by the electrophoretic deposition of a first coating layer comprising an electrophoretically depositable aqueous coating medium, to which a second coating layer, comprising a first color- and/or effect-imparting base lacquer coating medium, is applied wet-into-wet, and the first and second coating layers thus obtained are stoved jointly, whereupon a third coating layer comprising a second color- and/or effect-imparting base lacquer coating medium is applied and a fourth coating layer comprising a clear lacquer coating medium is applied wet-into-wet thereto and the third and fourth coating layers are stoved jointly, wherein the total dry coat thickness of the second and third coating layers produced from the base lacquer coating media is between 15 and 40 .mu.m and the proportion of the second coating layer is between 20 and 50% of the total dry coat thickness of the second and third coating layers.

Current mass production automobile coatings consist for the most part of a base lacquer/clear lacquer covering coating which is applied to a body which has been electrophoretically primed and coated with primer surfacer. In the course of this procedure, the base lacquer and the clear lacquer are preferably applied wet-into-wet, i.e. after a ventilation period, optionally with heating, and after the subsequent application of a clear lacquer, the base lacquer is stoved jointly with the latter. Processes which serve to reduce further stoving steps have also become known, in which the electrophoretically deposited primer coat and the primer surfacer coat are applied by the wet-into-wet method, as described in DE-A-41 26 476 or EP-A-0 595 186 for example. The primer surfacer coats have to be applied to give a dry film thickness of 30 .mu.m or more, which is customary for primer surfacer lacquers.
The procedure according to DE-A-41 26 476 and EP-A-0 595 186 is subject to restrictions as regards the composition of the primer surfacer coats which are applied wet-into-wet, i.e. it is not possible to use any desired primer surfacer coating media. Furthermore, the properties of the electro-dip lacquer material and of the primer surfacer material have to be matched to each other.
It is known from EP-A-0 265 363 that a previously stoved, cataphoretically deposited primer coat can be provided with a two-coat base lacquer/clear lacquer covering coat by the wet-into-wet method. The primer surfacer coat is dispensed with. An effect which is problematical, however, is that stone impact damage to motor vehicles coated by this process is particularly conspicuous, since on stone impact the primer coat is exposed due to the debonding of the covering lacquer. Whilst protection from corrosion is still in fact ensured, the visual impression cannot be tolerated, however.
For reasons of rationalisation and savings in material, there is a desire for a reduction in the coating thickness of the lacquer structure for the coating of motor vehicles, but without this resulting in significant losses in the overall level of properties thereof.

Herberts Gesellschaft Mit Beschrankter Haftung


Copolycarbonates having low intrinsic birefringence comprise structural units derived from hydroxyphenylindanol, from resorcinol, alkylenedioic acid or eugenolsiloxane, and, optionally, from a bisphenol, preferably bisphenol A. The copolycarbonates are useful for the fabrication of optical data recording media such as compact disks.

This invention relates to copolyestercarbonates, and more particularly copolyestercarbonates useful for the fabrication of optical disks.
Optical data recording media, including optical disks as exemplified by compact audio disks and CD-ROM disks used in computers, have become a major means of storing data and making it available. The data on an optical disk are read by a plane polarized laser beam, associated with a similar reference beam polarized in a perpendicular direction. For accurate reading, it is necessary to minimize differences in phase retardation of these laser beams upon passage through the disk.
In the further development of optical disks, particularly read-write disks and disks capable of storing larger amounts of data, various physical factors become important. One such factor which is closely related to the storage capability of the disk, is its birefringence, i.e., the difference between indices of refraction of light polarized in two directions perpendicular to each other. Birefringence has several components, caused by such factors as molecular structure of the raw material from which the disk is fabricated and degree of molecular orientation therein. "Orientational" or intrinsic birefringence of a polymer, ideally measured after perfect orientation of all polymer molecules by stretching, is a function solely of molecular structure.
It is possible to calculate the theoretical orientational birefringences of various polymers by considering the birefringence values of the monomers used to synthesize the polymer and their volume proportions in the polymer molecule. Thus, by balancing the birefringences of the monomers it is possible to prepare a polymer which theoretically has an orientational birefringence value of 0.
By far the most common polymers employed in optical disks are polycarbonates and copolyestercarbonates. They are peculiarly suited for this purpose by reason of their transparency and favorable physical properties. However, the bisphenol A polycarbonates, which are the principal ones currently being produced, are characterized by very high birefringence.
In U.S. Pat. No. 4,950,731, a series of polycarbonates having very low orientational birefringence is described. Said polycarbonates are typically copolycarbonates comprising structural units derived from 2,2-bis(4-hydroxyphenyl)propane, also known as "bisphenol A", and 6,6'-hydroxy-3,3,3',3'-tetramethyl-1,1'-spiro(bis)indane, hereinafter designated "SBI". These copolycarbonates are suitable in many ways for the fabrication of optical disks. However, there is room for improvement in such areas as hydrolytic stability, processability and ductility.
In particular, the glass transition temperatures of many SBI-bisphenol A copolycarbonates are above 200.degree. C. and they have relatively high melt viscosities. It is generally very difficult to process materials with such properties. To lower the melt viscosity, one can incorporate structural units derived from "soft block" monomers such as resorcinol, dodecanedioic acid or eugenolpolydimethylsiloxane, but in the case of SBI polycarbonates the proportion of "soft block" units may be so high that the melt stability of the polymer is adversely affected.
It is further found that interfacially prepared polycarbonates sometimes have such disadvantages as poor solubility and swelling behavior of SBI in contact with chlorinated solvents such as methylene chloride. The aforementioned patent describes a particular interfacial method which overcomes these disadvantages to some extent. However, it is cumbersome in that it requires several steps.

Optical disk grade copolyestercarbonates derived from hydroxyphenylindanols


Some embodiments provide a method of associating Mobile Management Entities (MMEs) of an evolved packet system (EPS) and Voice over long term evolution (LTE) via Generic Access (VoLGA) network controllers (VANCs). The method includes at a serving VANC, receiving a registration message from a user equipment (UE). The registration message includes an assigned Globally Unique Temporary Identity (GUTI) of the UE and the serving VANC is provisioned with MME-to-VANC mapping information. The method extracts an identification of a MME from the GUTI and determines an associated VANC based on the provisioned MME-to-VANC mapping information. The method then sends a message from the serving VANC to the associated VANC, the message indicating that the serving VANC is now serving the UE.

Licensed wireless systems provide mobile wireless communications to individuals using wireless transceivers. Licensed wireless systems refer to public cellular telephone systems and/or Personal Communication Services (PCS) telephone systems. Wireless transceivers include cellular telephones, PCS telephones, wireless-enabled personal digital assistants, wireless modems, and the like.
Increasing demand for high data speeds and lower packet latency has required the mobile service operators to upgrade the existing Universal Mobile Telecommunication System (UMTS) cellular technology. Long Term Evolution (LTE) is one such upgrade which provides improved spectral efficiency, lower costs, and improved service.
The decision was made in the third generation partnership (3GPP) standards to not continue to define and support circuit switched (CS) services in LTE (i.e., to not support the use of the existing CS call control protocol and procedures for voice calls). Instead, the expectation was that operators would transition to the use of IP Multimedia Subsystem (IMS)-based voice service in tandem with their addition of LTE (i.e., "4G") air interface and network technology.
In order to make the best use of the existing resources, access from the legacy core network infrastructure and services should be possible to provide CS services (e.g., voice and short message service "SMS"). This will allow avoiding a major switch in the voice call control paradigm as well as retaining the currently provided functionalities. Therefore, there is a need in the art to reuse parts of an existing technology, such as Generic Access Network (GAN), to provide CS services over the LTE networks.

Method and apparatus for network controller selection in a voice over long term evolution via generic access system


An aqueous coating composition is provided containing up to 50 weight percent, based on the total solids, of a cellulose mixed ester and a compatible amine neutralized acrylic resin.

Cellulose esters are valuable polymers which are useful in many plastic, film, coating and fiber applications. In coatings applications, cellulose esters are generally applied from organic solvent solutions. Because of health and environmental concerns from volatile organic content of solvent based coatings, water based coatings are becoming more in demand. There are waterborne coating formulation available containing polyesters and acrylics, but few contain cellulose esters due to their hydrophobic nature making them difficult to disperse or emulsify. When applied from organic solvent solutions as wood, leather, and metal coatings, cellulose esters impart desired properties such as, improved pigment dispersions, improved metallic flake orientation, improved solvent release, and higher gloss coatings. Cellulose esters also function as an excellent rheology control agent in solvent coating formulations. It would be very desirable to incorporate these excellent properties of cellulose esters into waterborne coating systems.
Previous attempts to produce a water dispersible cellulose ester coatings system have involved oxidation of cellulose ester, grafting of acrylic acid to cellulose esters, and reaction of anhydrides such as phthalic anhydride or succinic anhydride with the hydrolyzed cellulose esters to provide modified cellulose esters containing free carboxyl groups such as disclosed in the following U.S. patents; U.S. Pat. Nos. 4,435,531; 4,590,265; 4,960,814; 4,252,697. The reaction of anhydrides with cellulose esters results in a cellulose mixed ester. Coatings prepared from these cellulose mixed esters are made by neutralizing the cellulose mixed ester with an amine and forming an aqueous dispersion. Coating compositions made from these dispersions are not always stable and have volatile organics content (VOC) above 20 weight percent.
Other cellulose ester systems used in water based coating are disclosed in U.S. Pat. No. 3,318,714 (describing pigment dispersions in a cellulose acetate butyrate lacquer systems) and U.S. Pat. No. 3,220,865 (describing an emulsion coating composition based on cellulose acetate butyrate, and plasticizers).
In light of the above it would, be very desirable to be able to produce stable aqueous dispersions that are low in VOC.

Aqueous coatings composition contianing cellulose mixed ester and amine neutralized acrylic resin and the process for the preparation thereof