Abstract: A method for providing grades of service to unprotected traffic on an optical network that provides protection channels associated with working channels, defines a linearly ordered set of protection switch request priorities, and two or more grade of service priorities, and uses those priorities to enforce a protection access policy. The unprotected traffic may be of a high priority, approximating non-pre-emptable unprotected traffic (NUT); of low priority, like extra traffic; or may be of an intermediate priority between the two. This allows data transport providers to offer different unprotected transport services at different rates on protected links, in which the different unprotected transport services are associated with different probabilities of pre-emption.

Abstract: Processes for isolating, formulating, and shaping macrocyclic oligoesters were developed which allow efficient production of macrocyclic oligoesters substantially free from solvent, which may include additives, fillers, and catalysts.

Abstract: The invention relates to methods and systems for selective removal of catalyst residue from a depolymerization product stream without a water quench, as well as methods and systems for subsequent recovery of residual linear oligomer. The substantially metal-free and substantially water-free residual oligomer byproduct can then be advantageously used as recyclate in a process for preparing MPO. For example, the residual oligomer recyclate can be used as a reactant in the polymerization and subsequent depolymerization (cyclization) of low-acid polyester to form MPO.

Abstract: The invention relates to methods and systems for the use of an oligomer recyclate from a depolymerization product stream. The oligomer byproduct of a polyester depolymerization reaction can be used as a reactant in the formation of a polyester. For example, linear oligomer byproduct can be used as a reactant in a solution polymerization to form a low-acid polyalkylene terephthalate.

Abstract: The invention provides methods and systems for manufacturing low-acid polyalkylene terephthalate, for example, polybutylene terephthalate (PBT). The invention also provides methods and systems for preparing macrocyclic polyester oligomer (MPO) from low-acid polyalkylene terephthalate. Finally, the invention provides methods and systems for preparing MPO via reaction of a diol and a dialkyl ester in an organic solvent to form non-isolated, low-acid polyalkylene terephthalate which undergoes cyclization (depolymerization) to form MPO.

Abstract: In one aspect, the invention relates to processes for producing substantially free-flowing shapes of macrocyclic oligoester, wherein the freshly-shaped macrocyclic oligoester is maintained at elevated temperature for a sufficient time. In certain embodiments, the shapes are heated in water, thereby avoiding agglomeration during the heating process itself. In another aspect, the invention relates to processes for removing solvent from a solution of macrocyclic oligoester using elevated temperature, reduced pressure, or both, thereby obviating the need for an anti-solvent to precipitate the macrocyclic oligoester from the solution. Other aspects of the invention related to shaping of macrocyclic oligoesters are presented as well.

Abstract: The invention provides methods and formulations involving the use of promoters that accelerate the polymerization of macrocyclic polyester oligomers (MPOs). For example, in certain embodiments, the invention provides blends of macrocyclic polyester oligomer (MPO), catalyst, and promoter that are substantially stable at ambient temperature for a period of time. The blend material may be stored without premature polymerization of MPO or deactivation of catalyst. The invention also provides processes employing one-part, ready-to-polymerize blends that contain MPO, catalyst, and promoter, as well as processes in which the catalyst and promoter are used in separate streams and are contacted when it is desired to accelerate polymerization of MPO. Methods of the invention offer advantages in the manufacture of thermoplastic parts and composites, due at least in part to the unique properties of MPO.

Abstract: A method and corresponding network element configuration for delivering communications services between first and second survivable rings, each comprising a respective plurality of network elements, at least two of which are common to both rings. For each particular service, one of the common network elements is designated as a primary gateway node and another as a secondary gateway node. A primary inter-ring connection is established for the particular service by a switch at the primary gateway node, but no inter-ring connection is established at the secondary gateway node. The secondary gateway node comprises a controller for monitoring the status of the primary gateway node and establishing a new inter-ring connection for delivery of the service upon detecting a failure of the primary gateway node. This provides survivable inter-ring traffic which is bandwidth-efficient and with a low switching delay.

Abstract: An apparatus is provided for modifying a timing signal generated by a timing signal generator. The timing signal is modified indirectly by first modifying a power supply signal from a power supply upon which the timing signal generator is dependent to generate the timing signal. Initiating an introduction of at least one transient signal component of variable length by a transient insertion device into the power supply signal causes the timing signal generator to be disrupted and at least one transient signal component to be introduced within the timing signal. A particular implementation of the invention is an electrical circuit consisting of both active and passive electronic components.

Abstract: This invention relates to single-component and multi-component catalytic systems using aryl titanates. Aryl titanate compounds are useful as catalysts and co-catalysts in single-component and multi-component catalytic systems (e.g., for the polymerization of macrocyclic oligoesters and the depolymerization of polyesters). Multi-component catalytic systems using aryl titanates allow increased versatility in applications such as liquid molding.

Abstract: A method for processing automatic protection switch (APS) messages at a network element in a tunnel provisioned across a data transport network in order to provide for distributed processing of protection switch request messages involves receiving new APS message at the NE; determining whether the NE is an end point of the tunnel, or a tandem of the tunnel and processing the message accordingly. If the NE is a tandem, message processing involves using local information about tunnel segments of the tunnel only maintained by the NE, to update the local information, and to selectively forward the updated information to adjacent NEs of the tunnel. If the NE is an end point, it updates a status of the tunnel. In a preferred embodiment all NEs are responsible for controlling pending and preemption indicators, and for initiating tunnel condition messages, and the end point NEs are responsible for initiating all other messages.

Abstract: A method for providing grades of service to unprotected traffic on an optical network that provides protection channels associated with working channels, defines a linearly ordered set of protection switch request priorities, and two or more grade of service priorities, and uses those priorities to enforce a protection access policy. The unprotected traffic may be of a high priority, approximating non-pre-emptable unprotected traffic (NUT); of low priority, like extra traffic; or may be of an intermediate priority between the two. This allows data transport providers to offer different unprotected transport services at different rates on protected links, in which the different unprotected transport services are associated with different probabilities of pre-emption.

Abstract: A method for permitting a network element to transmit to a second network element a message over a link, that identifies a tunnel segment occupying predefined proportion of the data transport on the link, and a status of the tunnel, so that each tunnel may be provided with independent protection switching messaging involves providing an identifying scheme for locally identifying the tunnels passing through the tunnel segment. In order to permit this information to be sent over existing (narrow) automatic protection switching (APS) channels, the identifying scheme only provides a local identifier of the tunnel. To permit extended messaging to include messages that do not fit in a single K-byte overhead, extension bits are used to identify continuation of a message across multiple frames.

Abstract: Organo-titanate catalysts are prepared that are useful to catalyze depolymerization of a polyester to produce macrocyclic oligoesters substantially free from macrocyclic co-oligoesters.

Abstract: A rotor for a magnetic-drive centrifugal pump includes a core for supporting a magnetic assembly of magnets. An inner barrier covers at least part of the magnets. The inner barrier hermetically isolates the magnetic assembly within the impeller. For example, in one embodiment the inner barrier may be sealed or hermetically connected to the core at one or more seams. An outer barrier overlies the inner barrier.

Abstract: Processes for isolating, formulating, and shaping macrocyclic oligesters were developed which allow efficient production of macrocyclic oligoesters substantially free from solvent, which may include additives, fillers, and catalysts.

Abstract: A method and corresponding network element configuration for delivering communications services between first and second survivable rings, each comprising a respective plurality of network elements, at least two of which are common to both rings. For each particular service, one of the common network elements is designated as a primary gateway node and another as a secondary gateway node. A primary inter-ring connection is established for the particular service by a switch at the primary gateway node, but no inter-ring connection is established at the secondary gateway node. The secondary gateway node comprises a controller for monitoring the status of the primary gateway node and establishing a new inter-ring connection for delivery of said service upon detecting a failure of the primary gateway node. This provides survivable inter-ring traffic which is bandwidth-efficient and with a low switching delay.

Abstract: The present invention relates to a switching node for use in a synchronous optical network ring, where the ring is transporting data divided into first size blocks, for example OC-192 optical signals, characterized by data blocks of size 192. The switching node includes several primary receive and send connections, for receiving and transmitting inter-ring optical signals divided into second size blocks, for example OC-48 optical signals, characterized by data blocks of size 48. The switching node further includes a secondary receive and send connection for receiving and transmitting intra-ring optical signals divided into first size blocks. A critical component of the switching node is the main controller, responsible for routing incoming intra-ring first size blocks towards a primary send connection.