Search

Search Results

• 641. [Article] Low-power high-linearity digital-to-analog converters

  In this thesis work, a design of 14-bit, 20MS/s segmented digital-to-analog converter (DAC) is presented. The segmented DAC uses switched-capacitor configuration to implement 8 (LSB) + 6 (MSB) segmented ...

  Citation × Citation Citation Abstract Copy Title: Low-power high-linearity digital-to-analog converters Author: Kuo, Ming-Hung In this thesis work, a design of 14-bit, 20MS/s segmented digital-to-analog converter (DAC) is presented. The segmented DAC uses switched-capacitor configuration to implement 8 (LSB) + 6 (MSB) segmented architecture to achieve high performance for minimum area. The implemented LSB DAC is based on quasi-passive pipelined DAC that has been proven to provide low power and high speed operation. Typically, capacitor matching is the best among all integrated circuit components but the mismatch among nominally equal value capacitors will introduce nonlinear distortion. By using dynamic element matching (DEM) technique in the MSB DAC, the nonlinearity caused by capacitor mismatch is greatly reduced. The output buffer employed direct charge transfer (DCT) technique that can minimize kT/C noise without increasing the power dissipation. This segmented DAC is designed and simulated in 0.18 μm CMOS technology, and the simulated core DAC block only consumes 403 μW. Title: Low-power high-linearity digital-to-analog converters Author: Kuo, Ming-Hung In this thesis work, a design of 14-bit, 20MS/s segmented digital-to-analog converter (DAC) is presented. The segmented DAC uses switched-capacitor configuration to implement 8 (LSB) + 6 (MSB) segmented architecture to achieve high performance for minimum area. The implemented LSB DAC is based on quasi-passive pipelined DAC that has been proven to provide low power and high speed operation. Typically, capacitor matching is the best among all integrated circuit components but the mismatch among nominally equal value capacitors will introduce nonlinear distortion. By using dynamic element matching (DEM) technique in the MSB DAC, the nonlinearity caused by capacitor mismatch is greatly reduced. The output buffer employed direct charge transfer (DCT) technique that can minimize kT/C noise without increasing the power dissipation. This segmented DAC is designed and simulated in 0.18 μm CMOS technology, and the simulated core DAC block only consumes 403 μW. Close

• 642. [Article] Does Large-Scale offshore Aquaculture Farming in Western Australia Make Economic Sense? the Case of Yellowtail Kingfish

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Does Large-Scale offshore Aquaculture Farming in Western Australia Make Economic Sense? the Case of Yellowtail Kingfish Author: McLeod, Paul, McElroy, Seamus Abstract only. Title: Does Large-Scale offshore Aquaculture Farming in Western Australia Make Economic Sense? the Case of Yellowtail Kingfish Author: McLeod, Paul, McElroy, Seamus Abstract only. Close

• 643. [Article] Quantification of Trace Volatile Sulfur Compounds in Milk by Solid-Phase Microextraction and Gas Chromatography–Pulsed Flame Photometric Detection

  Originally published in Journal of Dairy Science (http://www.journalofdairyscience.org/) and copyrighted by the American Dairy Science Association.

  Citation × Citation Citation Abstract Copy Title: Quantification of Trace Volatile Sulfur Compounds in Milk by Solid-Phase Microextraction and Gas Chromatography–Pulsed Flame Photometric Detection Author: Torres, J. A., Qian, M. C., Vazquez-Landaverde, P. A. Originally published in Journal of Dairy Science (http://www.journalofdairyscience.org/) and copyrighted by the American Dairy Science Association. Title: Quantification of Trace Volatile Sulfur Compounds in Milk by Solid-Phase Microextraction and Gas Chromatography–Pulsed Flame Photometric Detection Author: Torres, J. A., Qian, M. C., Vazquez-Landaverde, P. A. Originally published in Journal of Dairy Science (http://www.journalofdairyscience.org/) and copyrighted by the American Dairy Science Association. Close

• 644. [Article] Temporal variations of beam attenuation coefficient on the Continental Rise off Nova Scotia

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Temporal variations of beam attenuation coefficient on the Continental Rise off Nova Scotia Author: Pak, Hasong, Zaneveld, J. Ronald Copyrighted by American Geophysical Union. Title: Temporal variations of beam attenuation coefficient on the Continental Rise off Nova Scotia Author: Pak, Hasong, Zaneveld, J. Ronald Copyrighted by American Geophysical Union. Close

• 645. [Article] Computational Modeling of a Diffusion Bonded Microchannel under High Pressure and Temperature

  Diffusion bonded microchannels provide significant benefits by reducing space requirements while improving thermal efficiency when used in heat exchangers. In particular, these microchannels have potential ...

  Citation × Citation Citation Abstract Copy Title: Computational Modeling of a Diffusion Bonded Microchannel under High Pressure and Temperature Author: Pratte, William Diffusion bonded microchannels provide significant benefits by reducing space requirements while improving thermal efficiency when used in heat exchangers. In particular, these microchannels have potential to improve efficiencies for combining concentrated solar power with supercritical CO2 Brayton cycles, where structures operate at high temperatures (760 ˚C) and high pressures (25 MPa). This work uses computational modeling to provide a design space for microchannel geometries under these conditions by using a Representative Volume Element approach. Additionally, low cycle fatigue results are used to develop a Manson-Coffin relation to predict the effects of plastic loading on the fatigue life of diffusion bonded specimens. Manson-Coffin relations at temperatures of both 760 ˚C and room temperature had respective R2 values of 0.9406 and 0.676, indicating reasonable reliability in results. Title: Computational Modeling of a Diffusion Bonded Microchannel under High Pressure and Temperature Author: Pratte, William Diffusion bonded microchannels provide significant benefits by reducing space requirements while improving thermal efficiency when used in heat exchangers. In particular, these microchannels have potential to improve efficiencies for combining concentrated solar power with supercritical CO2 Brayton cycles, where structures operate at high temperatures (760 ˚C) and high pressures (25 MPa). This work uses computational modeling to provide a design space for microchannel geometries under these conditions by using a Representative Volume Element approach. Additionally, low cycle fatigue results are used to develop a Manson-Coffin relation to predict the effects of plastic loading on the fatigue life of diffusion bonded specimens. Manson-Coffin relations at temperatures of both 760 ˚C and room temperature had respective R2 values of 0.9406 and 0.676, indicating reasonable reliability in results. Close

• 646. [Image] The Grundtvig Folk High School

  	Of all the Danish schools the ones which have received the greatest consideration by American agricultural leaders are the Peoples (or Folk) High Schools. These originated with the thought and vision of ...
  	Citation × Citation Citation Abstract Copy Title: The Grundtvig Folk High School Of all the Danish schools the ones which have received the greatest consideration by American agricultural leaders are the Peoples (or Folk) High Schools. These originated with the thought and vision of N.F.S. Grudtvig, bishop, historian, and teacher who was beginning his great work a little less than a century ago. Their educational aim is "to give clear notions of the civic community and the conditions of its welfare, an appreciation of the national character and the ability to express one's thoughts with ease and vigor, freedom and propriety." Five months' courses for men are given in the winter and three months' courses for women in the summer. Some technical training is given. With this the young men and women, for two generations, have been getting a vision of rural life in all of its fullness and an appreciation of the value of unselfish service. It was in 1856, on Bishop Grundtvig's 70th birthday, that a wealthy party in Copenhagen presented him with equipment for the fourth school to be established and developed under his personal direction. This school was located at Lynby. It is fairly typical of the 79 High Schools and Agricultural Colleges which have an annual total enrollment of 8100 students. Title: The Grundtvig Folk High School Of all the Danish schools the ones which have received the greatest consideration by American agricultural leaders are the Peoples (or Folk) High Schools. These originated with the thought and vision of N.F.S. Grudtvig, bishop, historian, and teacher who was beginning his great work a little less than a century ago. Their educational aim is "to give clear notions of the civic community and the conditions of its welfare, an appreciation of the national character and the ability to express one's thoughts with ease and vigor, freedom and propriety." Five months' courses for men are given in the winter and three months' courses for women in the summer. Some technical training is given. With this the young men and women, for two generations, have been getting a vision of rural life in all of its fullness and an appreciation of the value of unselfish service. It was in 1856, on Bishop Grundtvig's 70th birthday, that a wealthy party in Copenhagen presented him with equipment for the fourth school to be established and developed under his personal direction. This school was located at Lynby. It is fairly typical of the 79 High Schools and Agricultural Colleges which have an annual total enrollment of 8100 students. Close

• 647. [Article] Novel methods for crop load management of pear cultivars in the Pacific Northwest

  Novel approaches to crop load management of pear orchards in the Pacific Northwest (PNW) are necessary, but will need to vary according to the unique vegetative and reproductive growth habits of the cultivar. ...

  Citation × Citation Citation Abstract Copy Title: Novel methods for crop load management of pear cultivars in the Pacific Northwest Author: Arrington, Matthew A. Novel approaches to crop load management of pear orchards in the Pacific Northwest (PNW) are necessary, but will need to vary according to the unique vegetative and reproductive growth habits of the cultivar. 'D'Anjou' is vigorous and non-precocious; thus, strategies to limit vigor and induce early fruiting are required. In contrast, 'Bartlett' possesses a high fruit-setting efficiency and, consequently, is prone to over-setting fruit. Thus, crop reduction is necessary to achieve marketable fruit size, but hand thinning is time-consuming and costly. Two methods were investigated to resolve these issues: Root pruning of 'd'Anjou' pear trees and, chemical thinning of 'Bartlett' pears using abscisic acid (ABA). Root pruning was imposed on one or both sides of the tree row and compared to an untreated control plot at two sites: Moderate-density, 6th leaf 'd'Anjou'/OH x F 87; and, high-density, 4th leaf 'd'Anjou'/OH x F 87. Root pruning two-sides of the tree row consistently reduced shoot growth and the effects were partially dependent on tree age at the time of root pruning. Return bloom was positively affected by root pruning, but fruit weight was often reduced. Reduced fruit weight was not associated with mid-season water or nutrient deficits. Yield and yield efficiency the year following double-sided root pruning were improved with the greatest response occurring in the younger orchard (i.e., ~70% yield increase over control plots). Root pruning is a viable strategy to reduce vigor and improve precocity in high-density 'd'Anjou' plantings when performed in the 3rd or 4th year after planting. Thinning efficacy of abscisic acid (ABA) applied to 'Bartlett' pear trees, between petal fall and 12mm fruit size, was inconsistent. Among four trials, ABA produced a rate-responsive, transient reduction in stomatal conductance and net photosynthesis (Pn) of ~ 80% to 95% within hours of application, the effect lasted one to two days. By day three, Pn returned to ~80% of control plots and was fully recovered by 7-10 days after application. Thinning was best achieved at 100-125 ppm ABA. Higher rates caused greater fruitlet abscission but rates exceeding 400 ppm resulted in phytotoxicity and leaf abscission. In field trials, good thinning was observed in years when low natural light (i.e., cloudy conditions) occurred during the week immediately succeeding ABA applications. Only a few days of low light appeared necessary to elicit ABA-induced fruit abscission. To test the additive effect of shade on ABA-induced thinning, an experiment was designed to expose whole canopies to one of three levels of shade (0%, 44%, or 77%) and two levels of ABA (0 or 125 ppm). Shade houses were erected within hours of ABA application (~petal fall) and were left in place for 15 days. Both ABA and shade affected fruit abscission, but 44% shade did not significantly reduce fruit set compared to control plots. Photosynthetic active radiation (PAR) was reduced relative to the intensity of shade, but Pn was not. Moderate shade (i.e., 44%) led to only minor reductions of Pn, while 77% shade reduced Pn by 50% to 75% for the duration of the treatment period. ABA-induced thinning was not significantly improved by the addition of shade; however, two days of non-forecasted, cloudy conditions (i.e., low light) within the first week of the experiment invalidated comparisons to a true control (i.e., 0% shade). Given the short-term Pn limitation induced by ABA, in combination with the high carbon reserves of pear trees, ABA application may not be consistent enough to warrant commercial application. Title: Novel methods for crop load management of pear cultivars in the Pacific Northwest Author: Arrington, Matthew A. Novel approaches to crop load management of pear orchards in the Pacific Northwest (PNW) are necessary, but will need to vary according to the unique vegetative and reproductive growth habits of the cultivar. 'D'Anjou' is vigorous and non-precocious; thus, strategies to limit vigor and induce early fruiting are required. In contrast, 'Bartlett' possesses a high fruit-setting efficiency and, consequently, is prone to over-setting fruit. Thus, crop reduction is necessary to achieve marketable fruit size, but hand thinning is time-consuming and costly. Two methods were investigated to resolve these issues: Root pruning of 'd'Anjou' pear trees and, chemical thinning of 'Bartlett' pears using abscisic acid (ABA). Root pruning was imposed on one or both sides of the tree row and compared to an untreated control plot at two sites: Moderate-density, 6th leaf 'd'Anjou'/OH x F 87; and, high-density, 4th leaf 'd'Anjou'/OH x F 87. Root pruning two-sides of the tree row consistently reduced shoot growth and the effects were partially dependent on tree age at the time of root pruning. Return bloom was positively affected by root pruning, but fruit weight was often reduced. Reduced fruit weight was not associated with mid-season water or nutrient deficits. Yield and yield efficiency the year following double-sided root pruning were improved with the greatest response occurring in the younger orchard (i.e., ~70% yield increase over control plots). Root pruning is a viable strategy to reduce vigor and improve precocity in high-density 'd'Anjou' plantings when performed in the 3rd or 4th year after planting. Thinning efficacy of abscisic acid (ABA) applied to 'Bartlett' pear trees, between petal fall and 12mm fruit size, was inconsistent. Among four trials, ABA produced a rate-responsive, transient reduction in stomatal conductance and net photosynthesis (Pn) of ~ 80% to 95% within hours of application, the effect lasted one to two days. By day three, Pn returned to ~80% of control plots and was fully recovered by 7-10 days after application. Thinning was best achieved at 100-125 ppm ABA. Higher rates caused greater fruitlet abscission but rates exceeding 400 ppm resulted in phytotoxicity and leaf abscission. In field trials, good thinning was observed in years when low natural light (i.e., cloudy conditions) occurred during the week immediately succeeding ABA applications. Only a few days of low light appeared necessary to elicit ABA-induced fruit abscission. To test the additive effect of shade on ABA-induced thinning, an experiment was designed to expose whole canopies to one of three levels of shade (0%, 44%, or 77%) and two levels of ABA (0 or 125 ppm). Shade houses were erected within hours of ABA application (~petal fall) and were left in place for 15 days. Both ABA and shade affected fruit abscission, but 44% shade did not significantly reduce fruit set compared to control plots. Photosynthetic active radiation (PAR) was reduced relative to the intensity of shade, but Pn was not. Moderate shade (i.e., 44%) led to only minor reductions of Pn, while 77% shade reduced Pn by 50% to 75% for the duration of the treatment period. ABA-induced thinning was not significantly improved by the addition of shade; however, two days of non-forecasted, cloudy conditions (i.e., low light) within the first week of the experiment invalidated comparisons to a true control (i.e., 0% shade). Given the short-term Pn limitation induced by ABA, in combination with the high carbon reserves of pear trees, ABA application may not be consistent enough to warrant commercial application. Close

• 648. [Article] Textural and mineralogical characteristics of altered Grande Ronde basalt, northeastern Oregon : a natural analog for a nuclear waste repository in basalt

  Altered flows that are low-MgO chemical types of the Grande Ronde Basalt crop out in the steep walls of the Grande Ronde River canyon near Troy, Wallowa County, Oregon. The alteration effects in these ...

  Citation × Citation Citation Abstract Copy Title: Textural and mineralogical characteristics of altered Grande Ronde basalt, northeastern Oregon : a natural analog for a nuclear waste repository in basalt Author: Trone, Paul M. Year: 1987 Altered flows that are low-MgO chemical types of the Grande Ronde Basalt crop out in the steep walls of the Grande Ronde River canyon near Troy, Wallowa County, Oregon. The alteration effects in these flows are being investigated as a natural analog system to a high level nuclear waste repository in basalt. The flows within the study are referred to as the analog flow, in which the alteration effects are the strongest, and the superjacent flow. The analog flow crops out at Grande Ronde River level and a roadcut-outcrop is developed in the flow-top breccia of this flow. The two flows have been divided into flow zones based on intraflow structures observed in the field and primary igneous textures observed in thin section. These zones include, from the base upward, the flow interior, transition, and flow-top breccia zones of the analog flow, the interflow contact zone, and the flow interior and flow-top breccia zone of the superjacent flow. The intraflow structures and textures of the transition and interflow contact zones are atypical of Grande Ronde Basalt flows. The transition zone is transitional in textures between the flow interior zone and flow-top breccia zone, and includes holocrystalline spines mantled with fused in situ breccias. The interflow contact zone reflects the dynamic interaction during the emplacement of the superjacent flow manifested as invasive basalt tongues, clasts shed from tongues, pipe vesicles and tree molds, and pockets of breccia caught up in the base of the superjacent flow. Title: Textural and mineralogical characteristics of altered Grande Ronde basalt, northeastern Oregon : a natural analog for a nuclear waste repository in basalt Author: Trone, Paul M. Year: 1987 Altered flows that are low-MgO chemical types of the Grande Ronde Basalt crop out in the steep walls of the Grande Ronde River canyon near Troy, Wallowa County, Oregon. The alteration effects in these flows are being investigated as a natural analog system to a high level nuclear waste repository in basalt. The flows within the study are referred to as the analog flow, in which the alteration effects are the strongest, and the superjacent flow. The analog flow crops out at Grande Ronde River level and a roadcut-outcrop is developed in the flow-top breccia of this flow. The two flows have been divided into flow zones based on intraflow structures observed in the field and primary igneous textures observed in thin section. These zones include, from the base upward, the flow interior, transition, and flow-top breccia zones of the analog flow, the interflow contact zone, and the flow interior and flow-top breccia zone of the superjacent flow. The intraflow structures and textures of the transition and interflow contact zones are atypical of Grande Ronde Basalt flows. The transition zone is transitional in textures between the flow interior zone and flow-top breccia zone, and includes holocrystalline spines mantled with fused in situ breccias. The interflow contact zone reflects the dynamic interaction during the emplacement of the superjacent flow manifested as invasive basalt tongues, clasts shed from tongues, pipe vesicles and tree molds, and pockets of breccia caught up in the base of the superjacent flow. Close

• 649. [Article] SeQuential: Sustainability and Growth in the Biofuels Business

  SeQuential, a vertically-integrated biodiesel company based in Portland, Oregon, pursued a more sustainable supply and production strategy than many competitors by securing inputs from used cooking oil ...

  Citation × Citation Citation Abstract Copy Title: SeQuential: Sustainability and Growth in the Biofuels Business Author: Garten, Dave, Greene, Jacen, Niehaus, Carolyn, Aikath, Devdeep Year: 2017 SeQuential, a vertically-integrated biodiesel company based in Portland, Oregon, pursued a more sustainable supply and production strategy than many competitors by securing inputs from used cooking oil (UCO) rather than new crops. A fragmented U.S. biodiesel industry produced more than 1.25 billion gallons of the fuel in 2016 from a mix of virgin materials and UCO, but the environmental impact of crop-based biodiesel was increasingly controversial. Meanwhile, UCO collection had grown rapidly in recent years, and with strong forecasted growth, offered a potential additional revenue stream for vertically-integrated biodiesel firms. The price of the UCO used to produce SeQuential’s biodiesel and the fuel itself were driven by commodity indices, creating a highly volatile market. In addition, industry profitability was heavily reliant on government support. This support was manifested through funding for Renewable Identification Numbers (RINs) and tax credits. The recent election of a U.S. President publicly opposed to climate change mitigation, and the re-election of a sympathetic U.S. Congress, worsened perennial uncertainty around the renewal of these policies. Tyson Keever, President and CEO of SeQuential, had guided the company through a period of major growth and vertical integration by overseeing a series of regional mergers and acquisitions. As a result, the company now faced growing pains linked to employee turnover, operational integration and efficiency, and instilling a culture of sustainability in all SeQuential employees. At the same time, SeQuential was developing a new strategy for future growth, while attempting to mitigate increased regulatory and market uncertainty. In this case, students are tasked with developing a series of strategic, mission-aligned growth proposals that address these challenges. Title: SeQuential: Sustainability and Growth in the Biofuels Business Author: Garten, Dave, Greene, Jacen, Niehaus, Carolyn, Aikath, Devdeep Year: 2017 SeQuential, a vertically-integrated biodiesel company based in Portland, Oregon, pursued a more sustainable supply and production strategy than many competitors by securing inputs from used cooking oil (UCO) rather than new crops. A fragmented U.S. biodiesel industry produced more than 1.25 billion gallons of the fuel in 2016 from a mix of virgin materials and UCO, but the environmental impact of crop-based biodiesel was increasingly controversial. Meanwhile, UCO collection had grown rapidly in recent years, and with strong forecasted growth, offered a potential additional revenue stream for vertically-integrated biodiesel firms. The price of the UCO used to produce SeQuential’s biodiesel and the fuel itself were driven by commodity indices, creating a highly volatile market. In addition, industry profitability was heavily reliant on government support. This support was manifested through funding for Renewable Identification Numbers (RINs) and tax credits. The recent election of a U.S. President publicly opposed to climate change mitigation, and the re-election of a sympathetic U.S. Congress, worsened perennial uncertainty around the renewal of these policies. Tyson Keever, President and CEO of SeQuential, had guided the company through a period of major growth and vertical integration by overseeing a series of regional mergers and acquisitions. As a result, the company now faced growing pains linked to employee turnover, operational integration and efficiency, and instilling a culture of sustainability in all SeQuential employees. At the same time, SeQuential was developing a new strategy for future growth, while attempting to mitigate increased regulatory and market uncertainty. In this case, students are tasked with developing a series of strategic, mission-aligned growth proposals that address these challenges. Close

• 650. [Article] Acrylamide-Forming Potential and Agronomic Properties of Elite US Potato Germplasm from the National Fry Processing Trial

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Crop ...

  Citation × Citation Citation Abstract Copy Title: Acrylamide-Forming Potential and Agronomic Properties of Elite US Potato Germplasm from the National Fry Processing Trial Author: Wang, Yi, Parish, David I., Voglewede, Paul J., Endelman, Jeffrey B., Palta, Jiwan P., Porter, Gregory A., Novy, Richard G., Glynn, Martin T., Whitworth, Jonathan L., Sathuvalli, Vidyasagar R., Bussan, Alvin J., Pavek, Mark J., Navarro, Felix M., Thompson, Asunta L., Holm, David G., Bethke, Paul C. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Crop Science Society of America and can be found at: https://dl.sciencesocieties.org/publications/cs Title: Acrylamide-Forming Potential and Agronomic Properties of Elite US Potato Germplasm from the National Fry Processing Trial Author: Wang, Yi, Parish, David I., Voglewede, Paul J., Endelman, Jeffrey B., Palta, Jiwan P., Porter, Gregory A., Novy, Richard G., Glynn, Martin T., Whitworth, Jonathan L., Sathuvalli, Vidyasagar R., Bussan, Alvin J., Pavek, Mark J., Navarro, Felix M., Thompson, Asunta L., Holm, David G., Bethke, Paul C. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Crop Science Society of America and can be found at: https://dl.sciencesocieties.org/publications/cs Close