1. A heat exchanger, comprising:
an inlet;
an outlet; and
at least one passageway fluidly connecting the inlet and the outlet, the at least one passageway having a corrosive resistive feature that varies along a length of the at least one passageway, and the corrosive resistive feature including a wall thickness of the at least one passageway,
wherein the wall thickness of the at least one passageway increases in a stepwise manner at a predetermined position between the inlet and the outlet.
2. The heat exchanger of claim 1, wherein the wall thickness at an end of the at least one passageway near the outlet is greater than the wall thickness of an end at the at least one passageway near the inlet.
3. The heat exchanger of claim 2, wherein the wall thickness of the at least one passageway gradually increases along at least a portion of the length of the at least one passageway.
4. The heat exchanger of claim 1, wherein the wall thickness of the at least one passageway is greater near the outlet than near the inlet.
5. The heat exchanger of claim 4, wherein the wall thickness of the at least one passageway increases gradually along at least a portion of the passageway from the inlet to the outlet.
6. The heat exchanger of claim 1, wherein the feature further includes a coating on a wall of the at least one passageway.
7. The heat exchanger of claim 6, wherein the coating is only on a wall portion of the at least one passageway near to the outlet.
8. The heat exchanger of claim 6, wherein the coating on a wall portion of the at least one passageway near the outlet is thicker than the coating on a wall portion of the at least one passageway near the inlet.
9. A heat exchanger, comprising:
an inlet;
an outlet; and
at least one passageway fluidly connecting the inlet and the outlet, the at least one passageway having a corrosive resistive feature that varies along a length of the at least one passageway, the corrosive resistive feature including a wall material of the at least one passageway,
wherein the wall portion of the at least one passageway near the inlet is a first material and the wall portion of the at least one passageway near the outlet is a second material.
10. The heat exchanger of claim 9, wherein the first material is aluminum.
11. The heat exchanger of claim 10, wherein the second material is stainless steel.
12. An air handling system for an engine, comprising:
a supply of air;
a supply of recirculated exhaust gas;
a compressor in communication with the supply of air and the supply of recirculated exhaust gas, the compressor being configured to compress a mixture of air and recirculated exhaust gas;
an inlet manifold in fluid communication with the engine; and
a heat exchanger configured to cool the compressed air and recirculated exhaust gas mixture and to direct the cooled mixture to the inlet manifold, the heat exchanger including:
an inlet in communication with the supply of air and the supply of recirculated exhaust gas;
an outlet in communication with the inlet manifold; and
at least one passageway fluidly connecting the inlet and the outlet, the at least one passageway having a corrosive resistive feature that varies along a length of the at least one passageway, the corrosive resistive feature including a coating on a wall of the at least one passageway,
wherein the coating on a wall portion of the at least one passageway near the outlet is thicker than the coating on a wall portion of the at least one passageway near the inlet.
13. The air handling system of claim 12, wherein the coating is only on a wall portion of the at least one passageway near the outlet.
14. The air handling system of claim 12, wherein the feature further includes a wall material of the at least one passageway.
15. The air handling system of claim 14, wherein the wall portion of the at least one passageway near the inlet is aluminum, and the wall portion of the at least one passageway near the outlet is stainless steel.
16. The air handling system of claim 12, wherein the feature further includes a wall thickness of the at least one passageway.
17. The air handling system of claim 16, wherein the wall thickness at an end of the at least one passageway near the outlet is greater than the wall thickness of an end at the at least one passageway near the inlet.
18. The air handling system of claim 17, wherein the wall thickness of the at least one passageway gradually increases along the length of the at least one passageway.
19. The air handling system of claim 17, wherein the wall thickness of the at least one passageway increases in a stepwise manner at a predetermined position along the length of the at least one passageway.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1-8. (canceled)
9. A method of controlling and analyzing cellular radio communications exchanged between mobile terminals and base stations comprising the steps of: inserting a dummy mobile telephone network including a dummy base station and a dummy mobile terminal into a real network, the dummy network ensuring decoding and transparent and synchronous relaying of messages exchanged between real network and a real mobile, and control of access of the real mobiles from the real network or from the dummy network.
10. The method as claimed in claim 10, wherein the messages exchanged are messages of broadcast and dedicated signalling in the network access phases, or for the traffic in a situation of communication established.
11. The method as claimed in claim 10, comprising the following steps:
the dummy mobile performs a planning log of the network, and determines characteristics for each the dummy mobile optimizes the choice of a frequency and of the time parameters in conjunction with a dummy beacon signal,
the dummy base station transmits on this chosen frequency with the chosen time parameters the dummy beacon signal which is superimposed temporally with a signal normally transmitted by the network and is interpreted by the mobiles of the real base station as a real transmission.
12. The method as claimed in claim 11, wherein after the planning log of the network the dummy mobile transmits a selective jamming signal suitable for prohibiting the use of certain frequencies or of certain time intervals or slots by the mobile terminals present and for favoring their going on-hook to the dummy base station.
13. The method as claimed in claim 12, wherein after the mobile telephone has gone on-hook to the virtual base station, comprising the following steps:
decoding, interpreting and relaying in a transparent and synchronous manner the messages transmitted between the real base station and the real mobile, and:
authenticating the mobile terminals,
by using the call channel and the dedicated channels, implementing suitable procedures,
leading the mobile to provide its parameters IMSI, IMEI, TMSI, SRES according to appropriate modes and rates of repetition,
subsequently leading the dummy network to obtain by a processing specific to the invention the key of the mobile,
leading the dummy network to obtain, after processing, the key of the mobile for later sessions,
leading the mobile to register in its memory or in that of its SIM card, parameters and applications indicated by the dummy network,
leading the mobile to transmit the signalling, access and traffic signals on the frequencies indicated by the dummy network.
14. The method as claimed in claim 13, wherein the dummy network rejects the real mobile by forcing a procedure for cell transfer or handover or for relocation onto a real cell of the network other than, or by intentional degradation of the communication leading to its interruption or by forced interception of the protocol.
15. The method as claimed in claim 9, wherein a mobile telephone cellular digital public network is used.
16. A system for controlling and analyzing cellular radio communications exchanged between mobile telephones and base stations comprising:
a dummy mobile telephone network comprising a dummy base station and a dummy mobile terminal, the dummy network being inserted into the real network, wherein the dummy network is suitable for ensuring the decoding and a transparent and synchronous relaying of the messages exchanged between the real network and the real mobile, and the control of access of the real mobiles from the real network or from the dummy network.
17. The method as claimed in claim 10, wherein the situation of communication established is one of phone, data, short messages and DTMF.