Error 404--Not Found

From RFC 2068 Hypertext Transfer Protocol -- HTTP/1.1:

10.4.5 404 Not Found

The server has not found anything matching the Request-URI. No indication is given of whether the condition is temporary or permanent.

If the server does not wish to make this information available to the client, the status code 403 (Forbidden) can be used instead. The 410 (Gone) status code SHOULD be used if the server knows, through some internally configurable mechanism, that an old resource is permanently unavailable and has no forwarding address.

Error 404--Not Found

Error 404--Not Found

From RFC 2068 Hypertext Transfer Protocol -- HTTP/1.1:

10.4.5 404 Not Found

The server has not found anything matching the Request-URI. No indication is given of whether the condition is temporary or permanent.

If the server does not wish to make this information available to the client, the status code 403 (Forbidden) can be used instead. The 410 (Gone) status code SHOULD be used if the server knows, through some internally configurable mechanism, that an old resource is permanently unavailable and has no forwarding address.

Three-way catalysts for off-road engines
   Page 1     |     Page 2     |     Page 3   

Engine B emissions-control development

An emissions-control system was developed for Engine B operating on LPG using a closed-loop control system and a number of other components (Table 4). To assess the closed-loop operation of the system, SwRI monitored engine air/fuel ratio with a Horiba wide-range sensor, the signal from the control system's EGO sensor, and the duty cycle of the fuel-control valve (FCV). Initial development focused on achieving tight control of air/fuel ratio near stoichiometric conditions. Six calibrations of FCV control parameters were evaluated until the desired air/fuel ratio was achieved.

The upper half of Table 5 shows initial system results, along with open-loop baseline results for comparison. Since the catalyst did not have any run-in time, these data reflect "fresh" catalyst performance. Results indicated that the baseline fuel calibration was on the lean side of stoichiometry, which is standard practice for indoor lift-truck operation. Results also showed that operation in closed-loop control without a catalyst did not significantly reduce emissions with this engine.

Fuel-control calibration was further modified in attempts to achieve lower emissions (lower half of Table 5). Although SwRI researchers were successful with the B-24 calibration in reducing HC emissions, CO and NOx emissions increased. To further reduce emissions, a larger-volume catalytic converter from a Ford Ranger pickup was installed in place of the OEM converter. An emissions test was performed after a 4-h "de-greening" of the catalyst.

Results with the Ranger catalyst with calibration B-6 (Table 5) showed very low emissions rates of 0.13 g HC+NOx/kW•h (0.10 g HC+NOx/hp•h) and 2.82 g CO/kW•h (2.1 g CO/hp•h). However, in subsequent tests it was noted that the B-6 calibration would not consistently control mode 4 to the same air/fuel ratio. The B-24 calibration was re-entered into the engine control module and showed much better repeatability; then another baseline emissions test was performed using the B-24 calibration.

   Page 1     |     Page 2     |     Page 3   

Error 404--Not Found

Error 404--Not Found

From RFC 2068 Hypertext Transfer Protocol -- HTTP/1.1:

10.4.5 404 Not Found

The server has not found anything matching the Request-URI. No indication is given of whether the condition is temporary or permanent.

If the server does not wish to make this information available to the client, the status code 403 (Forbidden) can be used instead. The 410 (Gone) status code SHOULD be used if the server knows, through some internally configurable mechanism, that an old resource is permanently unavailable and has no forwarding address.