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Pressure-sensitive system for gas-temperature control

Description: From Summary: "A thermodynamic relation is derived and simplified for use as a temperature-limiting control equation involving measurement of gas temperature before combustion and gas pressures before and after combustion. For critical flow in the turbine nozzles of gas-turbine engines, the control equation is further simplified to require only measurements upstream of the burner. Hypothetical control systems are discussed to illustrate application of the control equations."
Date: March 4, 1948
Creator: Cesaro, Richard S. & Matz, Norman
Partner: UNT Libraries Government Documents Department

Investigation and Preparation of Polymer Films to Improve the Separation of Water and Salts in Saline Water Conversion

Description: From Introduction: "As will be explained in more detail elsewhere in this report, casting methods and drying conditions have been found to have a drastic effect on film permeability to both water and salt. Errors that became evident in temperature control indicated that some of the previous high rates were obtained at temperatures considerably higher than the 100 degrees C that was intended and reported."
Date: December 1962
Creator: Monsanto Research Corporation
Partner: UNT Libraries Government Documents Department

Temperature-control study of turbine region of turbojet engine, including turbine-blade time constants and starting characteristics

Description: Report presenting an investigation of a turbojet engine in an altitude test facility to supplement existing data relevant to gas-temperature control in a turbojet engine. The problems associated with gas-temperature control for minimizing turbine-blade damage are considered in the report.
Date: April 25, 1956
Creator: Phillips, W. E., Jr.
Partner: UNT Libraries Government Documents Department

Low-Voltage Room Thermostat Performance

Description: Report issued by the National Bureau of Standards over low voltage electric thermostats. Thermostat test results are discussed. This report includes illustrations, and photographs.
Date: April 1983
Creator: Kao, James Y.; Sushinsky, George; Didion, David A.; Mastascusa, E. J. & Chi, Joseph
Partner: UNT Libraries Government Documents Department

Undulator Changes Due to Temperature Excursions

Description: The temperature of the LCLS undulators has not been controlled during storage. The effects of the temperature excursions are documented in this note. After a number of LCLS undulators were tuned, fiducialized, and placed in storage anticipating their use, a test was made to ensure that their properties had not changed. The test revealed, however, that indeed the undulators had changed. Detailed study of this problem followed. We now believe that the gap of the undulators changes permanently when the undulators go through temperature excursions. We have tested the other possible cause, transportation, and do not see gap changes. In this note, we document how the undulators have changed since they were originally tuned. The undulators were tuned and fiducialized in the Magnetic Measurement Facility (MMF). Afterward, many of them (approximately 18) were taken to building 750 for storage during summer and fall 2007. Building 750 had no temperature control. The undulator temperatures went from 20 C, used for tuning, down to approximately 11 C during the winter. In January 2008, three of the undulators were brought back to the MMF for a check. All three undulators showed similar changes. Trajectories, phases, and most undulator properties stayed the same, but the fiducialization (beam axis position relative to tooling balls on the undulator) had changed. Further investigation showed that the undulator gap was altered in a periodic way along the magnetic axis with a net average gap change causing the fiducialization change. A new storage location in building 33 was found and future undulators were placed there. A failure in the temperature control, however, caused the undulators to get too hot. Again the gap changed, but with a different periodic pattern. This note documents the measured changes in the undulators. In particular, it shows the detailed history of undulator 39 which ...
Date: November 17, 2010
Creator: Wolf, Zachary; Levashov, Yurii & Reese, Ed
Partner: UNT Libraries Government Documents Department

Deprotection blue in extreme ultraviolet photoresists: influence of base loading and post-exposure bake temperture

Description: The deprotection blur of Rohm and Haas XP 5435, XP 5271, and XP5496 extreme ultraviolet photoresists has been determined as their base weight percent is varied. They have also determined the deprotection blur of TOK EUVR P1123 photoresist as the post-exposure bake temperature is varied from 80 C to 120 C. In Rohm and Haas XP 5435 and XP5271 resists 7x and 3x (respective) increases in base weight percent reduce the size of successfully patterned 1:1 line-space features by 16 nm and 8 nm with corresponding reductions in deprotection blur of 7 nm and 4 nm. In XP 5496 a 7x increase in base weight percent reduces the size of successfully patterned 1:1 line-space features from 48 nm to 38 nm without changing deprotection blur. In TOK EUVR P1123 resist, a reduction in post-exposure bake temperature from 100 C to 80 C reduces deprotection blur from 21 nm to 10 nm and reduces patterned LER from 4.8 nm to 4.1 nm.
Date: June 2, 2008
Creator: Anderson, Christopher N. & Naulleau, Patrick P.
Partner: UNT Libraries Government Documents Department

Direct-Write Precision Resistors for Ceramic Packages

Description: A direct-write approach to f abricate high precision resistors is reported. Special attention is paid to the effect of print thickrw;s on the resistance value of buried resistors after a low temperature co-firing process. The results show that the direct-write approach provides a superior line definition and thickness control over a traditional screen printing process. Microstructural analysis indicates that there is an interdiffused layer developed between the resistor material and the low temperature co-fired ceramic substrate. These observations are consistent with electrical IIH.SUKHIlentS which show that resistance increases as the effective cross-sectional area is reduced. Th: resistance data show that the standard deviations for resistors printed on a 6" x 6" area are 59Z0 and 15$Z0 for the direct-write and the screen-printed patterns, respectively.
Date: November 30, 1998
Creator: Dai, S.; Dimos, D.; Huang, R.F.; Rodriguez, M.A.; Wilcox, D. & Yang, P.
Partner: UNT Libraries Government Documents Department

Stabilizer for Temperature Control Equipment

Description: From abstract: "A simple electronic circuit is described, the use of which greatly improves the temperature regulations obtainable with Beta equipment. The circuit utilizes the time derivative of the temperature to counteract oscillation and overshoot. No other changes are required in existing equipment for installation of the stabilizer."
Date: May 14, 1945
Creator: Macleish, K. G. & Palmer, R. C.
Partner: UNT Libraries Government Documents Department

Microprocessor sampled data process controller

Description: A micro-miniaturized digital processor was utilized in the development of a sampled data process controller. While general purpose in nature, the processor was applied specifically to control temperature. Physically, the processor was found to be well suited for industrial environments, as its relatively slow speed and high switching voltage levels made it exceptionally noise immune. Successful application was found to be more dependent on external software development support than anything else. This is because of the very limited nature of the processor in terms of memory and input -- output peripherals. (auth)
Date: November 1, 1973
Creator: Seim, T.A.
Partner: UNT Libraries Government Documents Department

Quantification of Human Thermal Comfort for Residential Building's Energy Saving

Description: Providing conditioned and fully controlled room is the final goal for having a comfortable building. But on the other hand making smart controllers to provide the required cooling or heating load depending on occupants' real time feeling is necessary. This study has emphasized on finding a meaningful and steady state parameter in human body that can be interpreted as comfort criterion which can be expressed as the general occupants' sensation through their ambient temperature. There are lots of researches on human physiological behavior in different situations and also different body parts reaction to the same ambient situation. Body parts which have the biggest reliable linear fluctuation to the changes are the best subject for this research. For these tests, wrist and palm have been selected and their temperatures on different people have been measured accurately with thermal camera to follow the temperature trend on various comfort levels. It is found that each person reaches to his own unique temperature on these two spots, when he/ she feels comfortable, or in other word each person's body temperature is a precise nominate for comfort feeling of that individual. So in future by having this unique comfort parameter and applying them to the HVAC system temperature control, controlling the dynamic temperature and correlating the indoor condition depending on the occupants instant thermal comfort level, would be a rational choice to bring convenience while energy has been saved more.
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Date: August 2016
Creator: Sharifani, Pooya
Partner: UNT Libraries

Providing better indoor environmental quality brings economicbenefits

Description: This paper summarizes the current scientific evidence that improved indoor environmental quality can improve work performance and health. The review indicates that work and school work performance is affected by indoor temperature and ventilation rate. Pollutant source removal can sometimes improve work performance. Based on formal statistical analyses of existing research results, quantitative relationships are provided for the linkages of work performance with indoor temperature and outdoor air ventilation rate. The review also indicates that improved health and related financial savings are obtainable from reduced indoor tobacco smoking, prevention and remediation of building dampness, and increased ventilation. Example cost-benefit analyses indicate that many measures to improve indoor temperature control and increase ventilation rates will be highly cost effective, with benefit-cost ratios as high as 80 and annual economic benefits as high as $700 per person.
Date: June 1, 2007
Creator: Fisk, William & Seppanen, Olli
Partner: UNT Libraries Government Documents Department

Minimizing Reheat Energy Use in Laboratories

Description: HVAC systems that are designed without properly accounting for equipment load variation across laboratory spaces in a facility can significantly increase simultaneous heating and cooling, particularly for systems that use zone reheat for temperature control. This best practice guide describes the problem of simultaneous heating and cooling resulting from load variations, and presents several technological and design process strategies to minimize it. This guide is one in a series created by the Laboratories for the 21st century ('Labs21') program, a joint program of the U.S. Environmental Protection Agency and U.S. Department of Energy. Geared towards architects, engineers, and facilities managers, these guides provide information about technologies and practices to use in designing, constructing, and operating safe, sustainable, high-performance laboratories.
Date: November 29, 2005
Creator: Frenze, David; Mathew, Paul; Morehead, Michael; Sartor, Dale & Starr Jr., William
Partner: UNT Libraries Government Documents Department

Development of an Accurate Feed-Forward Temperature Control Tankless Water Heater

Description: The following document is the final report for DE-FC26-05NT42327: Development of an Accurate Feed-Forward Temperature Control Tankless Water Heater. This work was carried out under a cooperative agreement from the Department of Energy's National Energy Technology Laboratory, with additional funding from Keltech, Inc. The objective of the project was to improve the temperature control performance of an electric tankless water heater (TWH). The reason for doing this is to minimize or eliminate one of the barriers to wider adoption of the TWH. TWH use less energy than typical (storage) water heaters because of the elimination of standby losses, so wider adoption will lead to reduced energy consumption. The project was carried out by Building Solutions, Inc. (BSI), a small business based in Omaha, Nebraska. BSI partnered with Keltech, Inc., a manufacturer of electric tankless water heaters based in Delton, Michigan. Additional work was carried out by the University of Nebraska and Mike Coward. A background study revealed several advantages and disadvantages to TWH. Besides using less energy than storage heaters, TWH provide an endless supply of hot water, have a longer life, use less floor space, can be used at point-of-use, and are suitable as boosters to enable alternative water heating technologies, such as solar or heat-pump water heaters. Their disadvantages are their higher cost, large instantaneous power requirement, and poor temperature control. A test method was developed to quantify performance under a representative range of disturbances to flow rate and inlet temperature. A device capable of conducting this test was designed and built. Some heaters currently on the market were tested, and were found to perform quite poorly. A new controller was designed using model predictive control (MPC). This control method required an accurate dynamic model to be created and required significant tuning to the controller before good control ...
Date: June 30, 2008
Creator: Yuill, David
Partner: UNT Libraries Government Documents Department

Structural Design Feasibility Study for the Global Climate Experiment

Description: Neon, Inc. is proposing to establish a Global Change Experiment (GCE) Facility to increase our understanding of how ecological systems differ in their vulnerability to changes in climate and other relevant global change drivers, as well as provide the mechanistic basis for forecasting ecological change in the future. The experimental design was initially envisioned to consist of two complementary components; (A) a multi-factor experiment manipulating CO{sub 2}, temperature and water availability and (B) a water balance experiment. As the design analysis and cost estimates progressed, it became clear that (1) the technical difficulties of obtaining tight temperature control and maintaining elevated atmospheric carbon dioxide levels within an enclosure were greater than had been expected and (2) the envisioned study would not fit into the expected budget envelope if this was done in a partially or completely enclosed structure. After discussions between NEON management, the GCE science team, and Keith Lewin, NEON, Inc. requested Keith Lewin to expand the scope of this design study to include open-field exposure systems. In order to develop the GCE design to the point where it can be presented within a proposal for funding, a feasibility study of climate manipulation structures must be conducted to determine design approaches and rough cost estimates, and to identify advantages and disadvantages of these approaches including the associated experimental artifacts. NEON, Inc requested this design study in order to develop concepts for the climate manipulation structures to support the NEON Global Climate Experiment. This study summarizes the design concepts considered for constructing and operating the GCE Facility and their associated construction, maintenance and operations costs. Comparisons and comments about experimental artifacts, construction challenges and operational uncertainties are provided to assist in selecting the final facility design. The overall goal of this report is to provide a cost and technological basis ...
Date: December 1, 2008
Creator: Lewin,K.F. & Nagy, J.
Partner: UNT Libraries Government Documents Department

Physiomics Array: A Platform for Genome Research and Cultivation of Difficult-to-Cultivate Microorganisms Final Technical Report

Description: A scalable array technology for parametric control of high-throughput cell cultivations is demonstrated. The technology makes use of commercial printed circuit board (PCB) technology, integrated circuit sensors, and an electrochemical gas generation system. We present results for an array of eight 250 μl microbioreactors. Each bioreactor contains an independently addressable suite that provides closed-loop temperature control, generates feed gas electrochemically, and continuously monitors optical density. The PCB technology allows for the assembly of additional off-the-shelf components into the microbioreactor array; we demonstrate the use of a commercial ISFET chip to continuously monitor culture pH. The electrochemical dosing system provides a powerful paradigm for reproducible gas delivery to high-density arrays of microreactors. We have scaled the technology to a standard 96-well format and have constructed a system that could be easily assembled.
Date: July 10, 2006
Creator: Keasling, Jay D.
Partner: UNT Libraries Government Documents Department

Research On HVOF Thermal Sprays. Final Technical Report

Description: Independent control of particle velocity and temperature in the HVOF process has been achieved in this research, allowing the variables to change by 170 m/s and 200{degree}C, respectively. The independence was achieved using a specially designed nozzel with multiple axial injection ports, and with an inert diluent added to the oxygen used for combustion. With these changes, notable changes in splat morphology, porosity, and coating oxidation are readily apparent. Increased particle velocity correlates with improved splat deformation, but appears to have little effect on porosity or oxidation. Particle temperature, however, correlates strongly with splat deformation, porosity, and oxidation. In fact, highly dense coatings that have little oxidation can be formed with relatively low velocity particles that have average temperatures in the vicinity of the melting point of the material. This surprising result suggests particle temperature control is the key to creating dense, low-oxide HVOF-sprayed coatings.
Date: April 2, 2003
Creator: Settles, G. S.
Partner: UNT Libraries Government Documents Department

Biofeedback and Control of Skin Cell Proliferation in Psoriasis

Description: The present study was designed to determine the effect of skin-temperature-biofeedback training on cellular proliferation in three psoriasis patients. It was hypothesized that (a) psoriasis patients would be able to consciously decrease skin temperature of psoriatic tissue, and (b) there would be a positive correlation between rate of cellular proliferation and temperature change. Results obtained indicated biofeedback training to be effective in decreasing the surface temperature of psoriatic tissue. A 2 X 7 analysis of variance for two repeated measures indicated the change in skin temperatures as a function of sample period to be significant, F (6,26) = 3.29, p < .02. Generalization of temperature-training effects from the biofeedback to the no-feedback condition were observed. Rate of proliferation decreased from pretraining to posttraining biopsies.
Date: December 1977
Creator: Benoit, Larry J.
Partner: UNT Libraries

Thermal Imaging Control of Furnaces and Combustors

Description: The object if this project is to demonstrate and bring to commercial readiness a near-infrared thermal imaging control system for high temperature furnaces and combustors. The thermal imaging control system, including hardware, signal processing, and control software, is designed to be rugged, self-calibrating, easy to install, and relatively transparent to the furnace operator.
Date: February 28, 2003
Creator: Rue, David M.; Zelepouga, Serguei & Puri, Ishwar K.
Partner: UNT Libraries Government Documents Department

Preoperational test report, recirculation condenser cooling systems

Description: This represents a preoperational test report for Recirculation Condenser Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The four system provide condenser cooling water for vapor space cooling of tanks AY1O1, AY102, AZ1O1, AZ102. Each system consists of a valved piping loop, a pair of redundant recirculation pumps, a closed-loop evaporative cooling tower, and supporting instrumentation; equipment is located outside the farm on concrete slabs. Piping is routed to the each ventilation condenser inside the farm via below-grade concrete trenches. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.
Date: November 4, 1997
Creator: Clifton, F.T.
Partner: UNT Libraries Government Documents Department

Project W-320, 241-C-106 sluicing master calculation list

Description: This supporting document has been prepared to make the Master Calculation List readily retrievable. The list gives the status of the calculation (as-built, not used, applied, etc.), the calculation title, its originator, comments, and report number under which it was issued. Tank 241-C-106 has been included on the High Heat Load Watch List.
Date: August 7, 1998
Creator: Bailey, J.W.
Partner: UNT Libraries Government Documents Department

Preoperational test report, recirculation ventilation systems

Description: This represents a preoperational test report for Recirculation Ventilation Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system provides vapor space cooling of tanks AY1O1, AY102, AZ1O1, AZ102 and supports the ability to exhaust air from each tank. Each system consists of a valved piping loop, a fan, condenser, and moisture separator; equipment is located inside each respective tank farm in its own hardened building. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.
Date: November 11, 1997
Creator: Clifton, F.T.
Partner: UNT Libraries Government Documents Department

Preoperational test report, primary ventilation system

Description: This represents a preoperational test report for Primary Ventilation Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system provides vapor space filtered venting of tanks AY101, AY102, AZ101, AZ102. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.
Date: November 4, 1997
Creator: Clifton, F.T.
Partner: UNT Libraries Government Documents Department