Cardiovascular Responses to the Cold Pressor Test Are Not Modified in Healthy Adults with a History of Concussion

Click the PDF icon to download the abstract

Laparoscopic technology for the treatment of endometrial cancer

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135313/1/ijgo176.pd

Positive Operator-Valued Measure reconstruction of a beam-splitter tree based photon-number-resolving detector

Here we present a reconstruction of the Positive Operator-Value Measurement of a photon-number-resolving detector comprised of three 50:50 beamsplitters in a tree configuration, terminated with four single-photon avalanche detectors. The four detectors' outputs are processed by an electronic board that discriminates detected photon number states from 0 to 4 and implements a "smart counting" routine to compensate for dead time issues at high count rates

Spinning Reserve From Hotel Load Response: Initial Progress

This project was motivated by the fundamental match between hotel space conditioning load response capability and power system contingency response needs. As power system costs rise and capacity is strained demand response can provide a significant system reliability benefit at a potentially attractive cost. At ORNL s suggestion, Digital Solutions Inc. adapted its hotel air conditioning control technology to supply power system spinning reserve. This energy saving technology is primarily designed to provide the hotel operator with the ability to control individual room temperature set-points based upon occupancy (25% to 50% energy savings based on an earlier study [Kirby and Ally, 2002]). DSI added instantaneous local load shedding capability in response to power system frequency and centrally dispatched load shedding capability in response to power system operator command. The 162 room Music Road Hotel in Pigeon Forge Tennessee agreed to host the spinning reserve test. The Tennessee Valley Authority supplied real-time metering equipment in the form of an internet connected Dranetz-BMI power quality meter and monitoring expertise to record total hotel load during both normal operations and test results. The Sevier County Electric System installed the metering. Preliminary testing showed that hotel load can be curtailed by 22% to 37% depending on the outdoor temperature and the time of day. These results are prior to implementing control over the common area air conditioning loads. Testing was also not at times of highest system or hotel loading. Full response occurred in 12 to 60 seconds from when the system operator s command to shed load was issued. The load drop was very rapid, essentially as fast as the 2 second metering could detect, with all units responding essentially simultaneously. Load restoration was ramped back in over several minutes. The restoration ramp can be adjusted to the power system needs. Frequency response testing was not completed. Initial testing showed that the units respond very quickly. Problems with local power quality generated false low frequency signals which required testing to be stopped. This should not be a problem in actual operation since the frequency trip points will be staggered to generate a droop curve which mimics generator governor response. The actual trip frequencies will also be low enough to avoid power quality problems. The actual trip frequencies are too low to generate test events with sufficient regularity to complete testing in a reasonable amount of time. Frequency response testing will resume once the local power quality problem is fully understood and reasonable test frequency settings can be determined. Overall the preliminary testing was extremely successful. The hotel response capability matches the power system reliability need, being faster than generation response and inherently available when the power system is under the most stress (times of high system and hotel load). Periodic testing is scheduled throughout the winter and spring to characterize hotel response capability under a full range of conditions. More extensive testing will resume when summer outdoor temperatures are again high enough to fully test hotel response

Cursory analysis tool for the economic viability of cold thermal energy storage systems

Master of ScienceDepartment of Architectural Engineering and Construction ScienceJulia A. KeenDue to large strain placed on the utility grid during times of high commercial and industrial electricity usage, more emphasis is being placed on reducing energy use during these peak times. One of the more popular methods of reducing peak energy usage is the application of cold thermal energy storage (CTES) systems. CTES systems utilize high efficiency chillers to create ice during times of low power consumption or decreased energy cost. This ice is then used to supplement building cooling capacity during peak energy consumption. Although CTES is becoming more popular, frequency of implementation in the United States is still relatively low. Low implementation likely stems from the engineers' unfamiliarity with the system's design and the difficulty of performing the system's life cycle cost analysis. Though research may be done to overcome design unfamiliarity, the significant amount of time required to determine if CTES is economically viable for a project is still an obstacle. Thus, a simple time efficient initial analysis tool is needed. This report introduces an Excel based tool which provides a cursory project specific conservative economic analysis for the viability of CTES. The tool outlined in this report incorporates the many variables which influence CTES design, including the cooling load profile, utility structure, equipment information, and the system configuration of the project. An example analysis demonstrating the capability of the tool is completed at the end of the report. The ability of the tool to quickly provide conservative payback results for CTES systems aids the designer in deciding whether or not to continue with further economic analysis

Renal and Segmental Artery Hemodynamic Response to Mild Hypercapnia

Click the PDF icon to download the abstract