1. A radiation grid comprising:
an absorber having strip absorbing foil strips that extend in an extension direction for absorbing radiation arranged in an arrangement direction perpendicular to the extension direction, and having an incident plane where radiation enters and an emitting plane where radiation emits;
a first covering member for covering one plane of the incident plane or the emitting plane of the absorber;
a second covering member for covering the other plane other than the one plane of the absorber;
a first joining member arranged at a contact portion of each absorbing foil strip constituting the absorber and the first covering member for providing integration of both thereof; and
a second joining member arranged at a contact portion of each absorbing foil strip constituting the absorber and the second covering member for providing integration of both thereof,
a gap being provided between the first joining member and the second joining member, and
the first joining member having a thickness larger at both ends thereof in the extension direction than a center portion between the both ends.
2. The radiation grid according to claim 1, wherein
the second joining member has a thickness larger at both ends thereof in the extension direction than the center portion between the both ends.
3. The radiation grid according to claim 2, wherein
at both ends of the first joining member in the extension direction, the first joining member extends in a gap between the absorbing foil strips adjacent to each other for connecting the adjacent absorbing foil strips.
4. The radiation grid according to claim 2, wherein
at both ends of the second joining member in the extension direction, the second joining member extends in a gap between the absorbing foil strips adjacent to each other for connecting the adjacent absorbing foil strips.
5. The radiation grid according to claim 1, wherein
at both ends of the first joining member in the extension direction, the first joining member extends in a gap between the absorbing foil strips adjacent to each other for connecting the adjacent absorbing foil strips.
6. The radiation grid according to claim 5, wherein
at both ends of the second joining member in the extension direction, the second joining member extends in a gap between the absorbing foil strips adjacent to each other for connecting the adjacent absorbing foil strips.
7. The radiation grid according to claim 1, wherein
at both ends of the second joining member in the extension direction, the second joining member extends in a gap between the absorbing foil strips adjacent to each other for connecting the adjacent absorbing foil strips.
8. Radiographic apparatus comprising:
a radiation source for emitting radiation beams;
a radiation detecting device for detecting radiation beams to form detection signals;
a radiation grid arranged so as to cover a radiation detection surface where the radiation detecting device detects radiation;
an image formation device for forming an original image based on the detection signals; and
a trimming device for cutting off a given region in the original image to form a fluoroscopic image,
the given region in the original image being a region where a shadow of both ends in the radiation grid falls,
the radiation grid comprising:
an absorber having strip absorbing foil strips that extend in an extension direction for absorbing radiation arranged in an arrangement direction perpendicular to the extension direction, and having an incident plane where radiation enters and an emitting plane where radiation emits;
a first covering member for covering one plane of the incident plane or the emitting plane of the absorber;
a second covering member for covering the other plane other than the one plane of the absorber;
a first joining member arranged at a contact portion of each absorbing foil strip constituting the absorber and the first covering member for providing integration of both thereof; and
a second joining member arranged at a contact portion of each absorbing foil strip constituting the absorber and the second covering member for providing integration of both thereof,
a gap being provided between the first joining member and the second joining member, and
the first joining member having a thickness larger at both ends thereof in the extension direction than a center portion between the both ends.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An apparatus for facilitating overload control in a Session Initiation Protocol (SIP)-based network including an overloaded SIP server, the apparatus comprising:
a first SIP server of the network configured to receive SIP response messages from at least one downstream SIP server of the network, the downstream SIP server being associated with a path between the first SIP server and a target SIP server, the downstream SIP server being the overloaded SIP server and a nearest neighboring SIP server of the first SIP server, one or more of the SIP response messages including feedback information which comprises a utilization measure of the downstream SIP server;
wherein the first SIP server is further configured to generate a blocking message for delivery to a user agent associated with the network based on the feedback information.
2. The apparatus of claim 1 wherein the feedback information comprises a highest utilization measure of among utilization measures of a plurality of downstream SIP servers in the path between the first SIP server and the target SIP server.
3. The apparatus of claim 1 wherein the SIP response messages comprise at least one SIP 500 response message and wherein the blocking message is generated based at least in part on the SIP 500 response message.
4. The apparatus of claim 1 wherein the SIP response messages comprise at least one SIP 100 response message and wherein the blocking message is generated based at least in part on the SIP 100 response message.
5. The apparatus of claim 4 wherein the blocking message is generated based at least in part on an overload status value in a header of the SIP 100 response message.
6. The apparatus of claim 1 wherein the SIP response messages are received in response to at least one SIP INVITE request sent from the first SIP server.
7. The apparatus of claim 1 wherein the downstream SIP server comprises the target SIP server.
8. The apparatus of claim 1 wherein the downstream SIP server comprises an egress server of the network.
9. The apparatus of claim 1 wherein the downstream SIP server comprises a core server of the network.
10. The apparatus of claim 1 wherein the first SIP server comprises an ingress server for the user agent.
11. The apparatus of claim 1 wherein the first SIP server comprises a downstream SIP server relative to an ingress SIP server for the user agent.
12. The apparatus of claim 1 wherein a message routing process is adjusted responsive to the blocking message to reject at least one new call that would otherwise utilize the path between the first SIP server and the target SIP server that includes the downstream SIP server.
13. The apparatus of claim 1 wherein a message routing process is adjusted responsive to the blocking message to route at least one new call over another path between the first SIP server and the target SIP server that does not include the downstream SIP server.
14. A method for facilitating overload control in a Session Initiation Protocol (SIP)-based network including an overloaded SIP server, the method comprising:
receiving, by a first SIP server of the network, SIP response messages from at least one downstream SIP server of the network, the downstream SIP server being associated with a path between the first SIP server and a target SIP server, the downstream SIP server being the overloaded SIP server and a nearest neighboring SIP server of the first SIP server, one or more of the SIP response messages including feedback information which comprises a utilization measure of the downstream SIP server; and
generating, by the first SIP server, a blocking message for delivery to a user agent associated with the network based on the feedback information.
15. The method of claim 14 wherein a message routing process is adjusted responsive to the blocking message to reject at least one new call that would otherwise utilize the path between the first SIP server and the target SIP server that includes the downstream SIP server.
16. The method of claim 14 wherein a message routing process is adjusted responsive to the blocking message to route at least one new call over another path between the first SIP server and the target SIP server that does not include the downstream SIP server.
17. The method of claim 14 wherein:
the SIP response messages comprise at least one SIP 100 response message;
the blocking message is generated based at least in part on the SIP 100 response message; and
the blocking message is generated based at least in part on an overload status value in a header of the SIP 100 response message.
18. An apparatus for facilitating overload control in a Session Initiation Protocol (SIP)-based network including an overloaded SIP server, the apparatus comprising:
a downstream SIP server of the network configured to send SIP response messages to a first SIP server of the network, the downstream SIP server being associated with a path between the first SIP server and a target SIP server, the downstream SIP server being the overloaded SIP server and a nearest neighboring SIP server of the first SIP server, one or more of the SIP response messages including feedback information which comprises a utilization measure of the downstream SIP server;
wherein the feedback information is utilized to generate a blocking message for delivery to a user agent associated with the network.
19. The apparatus of claim 18 wherein:
the SIP response messages comprise at least one SIP 100 response message;
the blocking message is generated based at least in part on the SIP 100 response message; and
the blocking message is generated based at least in part on an overload status value in a header of the SIP 100 response message.
20. The apparatus of claim 18 wherein a message routing process is adjusted responsive to the blocking message to route at least one new call over another path between the first SIP server and the target SIP server that does not include the downstream SIP server.