摘要:
In a method of producing isotopes in a light water power reactor, one or more targets within the reactor may be irradiated under a neutron flux to produce one or more isotopes. The targets may be assembled into one or more fuel bundles that are to be loaded in a core of the reactor at a given outage. Power operations in the reactor irradiate the fuel bundles so as to generate desired isotopes, such as one or more radioisotopes at a desired specific activity or stable isotopes at a desired concentration.
摘要:
A rod assembly for a fuel bundle of a nuclear reactor may include an upper end piece, lower end piece and a plurality of rod segments attached between the upper and lower end pieces and to each other so as to form an axial length of the rod assembly. The rod assembly may include an adaptor subassembly provided at given connection points for connecting adjacent rod segments or a given rod segment with one of the upper and lower end pieces. The connection points along the axial length of the rod assembly may be located where the rod assembly contacts a spacer in the fuel bundle. One (or more) of the rod segments may include an irradiation target therein for producing a desired isotope when a fuel bundle containing one (or more) rod assemblies is irradiated in a core of the reactor.
摘要:
In a method of determining an operating margin to a given operating limit in a nuclear reactor, operational plant data from an on-line nuclear reactor plant is accessed, and reactor operation is simulated off-line using the operational plant data to generate predicted dependent variable data representative of the given operating limit. The predicted dependent variable data is normalized for evaluation with normalized historical dependent variable data from stored operating cycles of plants having a similar plant configuration to the on-line plant. A time-dependent average bias and a time-dependent uncertainty value for the predicted dependent variable data are determined using the normalized historical dependent variable data, and a risk-tolerance level for the on-line plant is obtained. An operating margin to the given operating limit is determined based on the determined time time-dependent average bias value and time-dependent uncertainty value so as to satisfy the risk-tolerance level of the evaluated plant.
摘要:
An apparatus for supporting a pipe segment during installation has been developed. The support includes a frame with two parallel arms and two beams that connect the arms, where each beam extends downward from the arms. Also included are four support bearings located at each corner of the frame, where the bearings provide four separate points of contact for a pipe segment.
摘要:
The present invention relates to a multipart business form that includes at least one removable and potentially formable identification card, band, tag or badge on one portion of the substrate and at least one separable postcard on the second portion of the multipart business form. The postcard portion can be used as a response piece, request for information or simply as a remembrance piece for an event which triggered the issuance of the identification portion.
摘要:
A method, arrangement and computer program is described for generating a database of selectable fresh fuel bundle designs usable in one or more nuclear reactors. In an example, an initial population of candidate fresh fuel bundle designs may be generated and a set of rod-type changes to make to a given candidate in the initial population may be established. A given candidate fresh fuel bundle may be modified by making at least one rod-type change from the set therein. A core loaded with the modified bundle design may be simulated to generate bundle performance outputs. The bundle performance outputs may be ranked based on a plurality of user-input limits. The modified candidate fresh fuel bundle design may be stored, if the bundle performance outputs meet, or are within an accepted margin to, the user-input limits, so as to generate the database.
摘要:
A semiconductor manufacturing method comprises forming a leveling guard ring defining an interior area into which are fabricated one or more devices. In certain embodiments two or more matched devices, such as in a common centroid layout, are fabricated in the interior area. The guard ring is formed on at least one particular layer for a particular processing step. By the guard ring overwhelming the effect of local features' elevation differences, photoresist thereafter applied consequently has a more uniform height across the interior area, resulting in more uniform devices. In some embodiments, a plurality of guard rings enclosing respective arrays of matched devices are arranged over the surface of a semiconductor wafer, spaced apart so as to be not local to one another. Based on the equalizing effect by each of the guard rings, the respective devices arranged in the interior areas are more evenly matched to equivalent devices in far-spaced guard rings. Thus, both local and global matching are achieved.
摘要:
A connector module for use with a shielded housing uses a lever-actuated wedge member to lift a flexible locking tab of the shielded housing over a locking pin of the connector module. The wedge member has a pointed end that faces the locking pin so that the wedge member can be slid between the connector module and the shielded housing flexible tab that engages the locking pin. The wedge member is moved by way of a lever within the connector module and which pivots about a fulcrum in the connector module. Moving the lever one direction moves the wedge member in an opposite direction.
摘要:
The present invention relates to a laminate that is imprintable, such as through non-impact printing means, for use in creating personalized pockets on demand for use with presentation folders, document containment devices and other items for which an auxiliary pocket may be useful. The pocket of the present invention is formed from a first sheet having patterns coated thereon, including patterns of adhesive and release which is then attached to a second or release sheet to protect the adhesive coated portions of the substrate. The patterns of release and adhesive enable the application of the pocket portion to a blank suitable for use in forming a presentation folder or other structure or item for which a pocket may be useful or beneficial.
摘要:
In the method for reactor simulation, a user modifies one or more design inputs used in creating a response surface. The response surface defines relationships between the design inputs and operational outputs of at least one or more aspects of a core design. A reactor simulation is then generated based on the response surface for the core design and the modified design input.