Performance of variable-orifice nozzles for liquid fertilizer applications

Citation: Sharda, A., Fulton, J. P., & Taylor, R. K. (2016). Performance of variable-orifice nozzles for liquid fertilizer applications. Applied Engineering in Agriculture, 32(3), 347-352. doi:10.13031/aea.32.11428Variable-rate application continues to gain interest among precision agriculture practitioners including the use of crop sensor technology for application of nitrogen in grain crops. For liquid fertilizers, variable-orifice nozzles are being implemented since they provide a much larger nozzle flow range compared to traditional fixed orifice nozzles. However, understanding the performance of variable-orifice nozzles under different field operating conditions has been limited. Therefore, the objective of this study was to evaluate the performance of variable orifice nozzles in support of variable-rate application. Two common variable-orifice nozzles offered by different companies were selected for this study. They were tested over three flow ranges (0.76 to 1.89 L/min) with all tests replicated three times. A commercially available 18.6-m, wet boom sprayer equipped with 37 nozzle bodies was used. Nozzles were numbered but then randomly assigned a position along the boom. To evaluate the performance of an individual nozzle, three random nozzle locations along the spray boom were established for both sets of nozzles. Therefore, 18 tests per replication were required to include the 3 flow rates, 3 different locations, and 2 nozzle types. Once the desired flow rate test was established, tip flow was measured using SpotOn Sprayer Calibrator technology. Tip flows were recorded and statistical analyses performed to evaluate flow uniformity (CV) across the boom but also detect off-rate errors by individual nozzles and locations across the boom. With the exception of a few nozzles, the uniformity across the spray boom, as defined by the CV, was acceptable for both nozzle types over approximately a 2:1 flow range. Both nozzle types were less uniform at the low flow rate. There were three nozzles of each type that resulted in unacceptable flow errors in multiple tests. © 2016 American Society of Agricultural and Biological Engineers

Development and evaluation of an automated spray patternator using digital liquid level sensors

Citation: Luck, J. D., Schaardt, W. A., Forney, S. H., & Sharda, A. (2016). Development and evaluation of an automated spray patternator using digital liquid level sensors. Applied Engineering in Agriculture, 32(1), 47-52. doi:10.13031/aea.32.11381The purpose of this study was to develop and evaluate an automated spray pattern measurement system which utilized digital liquid level sensors to quantify the coefficient of variation (CV) for different nozzle configurations. The overall system was designed to measure nozzle effluent in 25 mm divisions from 38.1 to 76.2 cm in width for multiple nozzle configurations with a total patternator surface width of 3.05 m. The patternator surface and data collection system were designed and developed to achieve three primary goals: patternator surface division accuracy, data collection system accuracy, and data collection system repeatability. Patternator surface measurements indicated an average standard deviation of approximately 0.1 mm (0.4%) which would not contribute significantly to spray pattern CV estimates. To quantify the measurement accuracy, the automated system was compared to manual data collection using weights collected from graduated cylinders. Statistical analysis revealed no difference (p > 0.05) between CV estimates from the manual and automated data collection methods. The average difference in CV between the two methods was 0.15% which considered 12 tests per method. Repeatability was also a primary concern, the standard deviation among CV values for tests conducted with the automated system was only 0.35%. The evaluation of the system provided confidence that suitable results would be acquired for different nozzle configurations consisting of acceptable or relatively poor spray patterns. © 2016 American Society of Agricultural and Biological Engineers

E-Mail Management: A Techno-Managerial Research Perspective

A panel session on e-mail management was organized at ICIS 2005 in Las Vegas, Nev. The panelists provided perspectives from industry as well as academia and discussed various problems in e-mail management, research methodologies to address these problems, various research opportunities, and an integrative framework for research on e-mail management. This paper succinctly summarizes the presentations made by the panelists during the session and issues raised by the audience. A rich bibliography and Web links are provided at the end for researchers interested in this area of research

Ecological Validity of Don\u27t Remember and Don\u27t Know For Distinguishing Accessibility-Versus Availability-Based Retrieval Failures In Older and Younger Adults: Knowledge For News Events

With pursuit of incremental progress and generalizability of findings in mind, we examined a possible boundary for older and younger adults’ metacognitive distinction between what is not stored in memory versus merely inaccessible with materials that are not process pure to knowledge or events: information regarding news events. Participants were asked questions about public events such as celebrity news, tragedies, and political events that were widely experienced in the previous 10–12 years, responding “I don’t know” (DK) or “I don’t remember” (DR) when retrieval failed. Memories of these events are relatively recently acquired in rich, naturalistic contexts and are likely not fully separated from episodic details. When retrieval failed, DR items were recognized with higher accuracy than DK items, both immediately and 2 years later, confirming that self-reported not remembering reflects failures of accessibility, whereas not knowing better captures a lack of availability. In fact, older adults distinguished between the causes of retrieval failures more precisely than younger adults. Together, these findings advance the reliability, validity, and generalizability of using DR and DK as a metacognitive tool to address the phenomenological experience and behavioral consequences of retrieval failures of information that contains both semantic and episodic features. Implications for metacognition in aging and related constructs like familiarity, remembering, and knowing are discussed

The Internet of Things (IoT): Platforms, Analytics, Security, Business Model, and Human Interaction

According to Consumer Electronics Show (CES) 2017 and a number of recent research reports in 2016 and 2017 from Gartner, Deloitte, McKinsey, and Info-Tech Research Group, the Internet of Things (IoT) is projected to be a multi-trillion dollar opportunity. However, there are numerous issues and requirements in IoT, such as platforms, analytics, gateways and devices (including sensors) management; communication services (i.e., M2M and networking protocols); security and privacy; and user interactions. In addition, various perspectives for monetizing IoT, as a business model, will be considered. The IoT panel proposal will cover IoT platform, gateway and devices; communications services; IoT analytics; security and privacy; business model and business value of IoT; and human interaction with IoT. Each panelist will present the assigned IoT topics

A Case Study Concerning The Effects Of Controller Response And Turning Movements On Application Rate Uniformity With A Self-Propelled Sprayer

The use of precision agriculture technologies such as automatic boom section control allows producers to reduce off-target application when applying herbicides. While automatic boom section control provides benefits, pressure differences across the spray boom resulting from boom section actuation may lead to off-rate application errors. Off-rate errors may also result from spray rate controller compensation for ground speed changes or velocity variation across the spray boom during turning movements. This project focused on characterizing application rate variation for three fields located in central Kentucky. GPS coordinates, boom control status, and nozzle pressure data (at 15 nozzle locations) were recorded as the sprayer traversed the study fields. Control section coverage areas and nozzle flow rates (calculated from the nozzle pressure with manufacturer calibration data) were used to estimate application rates. Results indicated the majority of each field received application rates at or below the target rate, as only 25% to 36% of the area in the study fields received application rates within the target rate ±10%. Spray rate controller lag time appeared to contribute to lower application rates as the sprayer accelerated and higher application rates as the sprayer decelerated as the controller attempted to compensate for changes in sprayer velocity. In addition, as boom control sections were turned off, pressure increases in the remaining sections resulted in higher application rates. Conversely, as boom sections were turned on, spray rate controller lag time may have contributed to lower application rates. Estimated application rate maps were also generated from the data to allow for a visual summary of the potential errors

An injectable bone marrow-like scaffold enhances T cell immunity after hematopoietic stem cell transplantation.

Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative treatment for multiple disorders, but deficiency and dysregulation of T cells limit its utility. Here we report a biomaterial-based scaffold that mimics features of T cell lymphopoiesis in the bone marrow. The bone marrow cryogel (BMC) releases bone morphogenetic protein-2 to recruit stromal cells and presents the Notch ligand Delta-like ligand-4 to facilitate T cell lineage specification of mouse and human hematopoietic progenitor cells. BMCs subcutaneously injected in mice at the time of HSCT enhanced T cell progenitor seeding of the thymus, T cell neogenesis and diversification of the T cell receptor repertoire. Peripheral T cell reconstitution increased ~6-fold in mouse HSCT and ~2-fold in human xenogeneic HSCT. Furthermore, BMCs promoted donor CD4+ regulatory T cell generation and improved survival after allogeneic HSCT. In comparison to adoptive transfer of T cell progenitors, BMCs increased donor chimerism, T cell generation and antigen-specific T cell responses to vaccination. BMCs may provide an off-the-shelf approach for enhancing T cell regeneration and mitigating graft-versus-host disease in HSCT

The Internet of Things: Multi-faceted Research Perspectives

Living beyond the hype, the Internet of things (IoT) continues to grow and has clearly emerged as a leading-edge topic in information systems. As the IoT moves beyond novel technologies and exploratory sandbox initiatives to ubiquitous technologies and full production, understanding the phenomenon surrounding IoT challenges and issues has become even more important. In this paper, we explore the critical issues and challenges currently facing IoT adoption and implementation in order to identify areas that require further study. Specifically, we discuss IoT from several key perspectives including IoT connectivity, platforms and 5G, IoT analytics, IoT privacy, security, and litigation risks, IoT business value and monetization, and human interaction with IoT and design considerations Finally, through identifying the current state of IoT and IoT research, we identify potential areas of contribution and future directions for IoT research

Semiautomated Glasgow-Blatchford Bleeding Score helps direct bed placement for patients with upper gastrointestinal bleeding.

OBJECTIVE: The Glasgow-Blatchford Bleeding Score (GBS) was designed to identify patients with upper gastrointestinal bleeding (UGIB) who do not require hospitalisation. It may also help stratify patients unlikely to benefit from intensive care. DESIGN: We reviewed patients assigned a GBS in the emergency room (ER) via a semiautomated calculator. Patients with a score ≤7 (low risk) were directed to an unmonitored bed (UMB), while those with a score of ≥8 (high risk) were considered for MB placement. Conformity with guidelines and subsequent transfers to MB were reviewed, along with transfusion requirement, rebleeding, length of stay, need for intervention and death. RESULTS: Over 34 months, 1037 patients received a GBS in the ER. 745 had an UGIB. 235 (32%) of these patients had a GBS ≤7. 29 (12%) low-risk patients were admitted to MBs. Four low-risk patients admitted to UMB required transfer to MB within the first 48 hours. Low-risk patients admitted to UMBs were no more likely to die, rebleed, need transfusion or require more endoscopic, radiographic or surgical procedures than those admitted to MBs. No low-risk patient died from GIB. Patients with GBS ≥8 were more likely to rebleed, require transfusion and interventions to control bleeding but not to die. CONCLUSION: A semiautomated GBS calculator can be incorporated into an ER workflow. Patients with a GBS ≤7 are unlikely to need MB care for UGIB. Further studies are warranted to determine an ideal scoring system for MB admission