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Search Results: 1 - 10 of 170942 matches for " Daniel K. Fisher "
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Rapid Deployment of Internet-Connected Environmental Monitoring Devices  [PDF]
Daniel K. Fisher
Advances in Internet of Things (AIT) , 2014, DOI: 10.4236/ait.2014.44007
Abstract: Advances in electronic sensing and monitoring systems and the growth of the communications infrastructure have enabled users to gain immediate access to information and interaction with physical devices. To facilitate the uploading, viewing, and sharing of data via the internet, while avoiding the complexities and expense of creating personal web servers, a number of service providers have created websites offering free data hosting and viewing capabilities. Simple setup and configuration routines and available application programming interfaces allow users to quickly and easily interface sensing and monitoring devices to the internet. To demonstrate the ease and feasibility of deploying internet-connected devices, an urban landscape environmental monitoring system, consisting of two wireless field sensing systems and a wireless central receiver, was developed. The field-data sensing units consisted of Arduino microcontroller platforms, sensors, and Xbee radio modems, while the receiver consisted of an Arduino microcontroller, Xbee radio, and Ethernet module connected to an internet modem. The receiver collected and stored data from the wireless transmitters, and uploaded the data to the Xively Cloud Services data hosting and sharing website. Real-time and archived sensor data were then made available for public viewing via the internet and a web browser. Data-sharing services such as Xively provide rapid and convenient means of developing internet-accessible data-collection and viewing applications, enabling enhanced access to the Internet of Things.
Mobile Open-Source Plant-Canopy Monitoring System  [PDF]
Daniel K. Fisher, Yanbo Huang
Modern Instrumentation (MI) , 2017, DOI: 10.4236/mi.2017.61001
Abstract: Many agricultural applications, including improved crop production, precision agriculture, and phenotyping, rely on detailed field and crop information to detect and react to spatial variabilities. Mobile farm vehicles, such as tractors and sprayers, have the potential to operate as mobile sensing platforms, enabling the collection of large amounts of data while working. Open-source hardware and software components were integrated to develop a mobile plant-canopy sensing and monitoring system. The microcontroller-based system, which incorporated a Bluetooth radio, GPS receiver, infrared temperature and ultrasonic distance sensors, micro SD card storage, and voltage regulation components, was developed at a cost of US$292. The system was installed on an agricultural vehicle and tested in a soybean field. The monitoring system demonstrates an application of open-source hardware to agricultural research and provides a framework for similar or additional sensing applications.
Open-Source Hardware Is a Low-Cost Alternative for Scientific Instrumentation and Research  [PDF]
Daniel K. Fisher, Peter J. Gould
Modern Instrumentation (MI) , 2012, DOI: 10.4236/mi.2012.12002
Abstract: Scientific research requires the collection of data in order to study, monitor, analyze, describe, or understand a particular process or event. Data collection efforts are often a compromise: manual measurements can be time-consuming and labor-intensive, resulting in data being collected at a low frequency, while automating the data-collection process can reduce labor requirements and increase the frequency of measurements, but at the cost of added expense of electronic data-collecting instrumentation. Rapid advances in electronic technologies have resulted in a variety of new and inexpensive sensing, monitoring, and control capabilities which offer opportunities for implementation in agricultural and natural-resource research applications. An Open Source Hardware project called Arduino consists of a programmable microcontroller development platform, expansion capability through add-on boards, and a programming development environment for creating custom microcontroller software. All circuit-board and electronic component specifications, as well as the programming software, are open-source and freely available for anyone to use or modify. Inexpensive sensors and the Arduino development platform were used to develop several inexpensive, automated sensing and datalogging systems for use in agricultural and natural-resources related research projects. Systems were developed and implemented to monitor soil-moisture status of field crops for irrigation scheduling and crop-water use studies, to measure daily evaporation-pan water levels for quantifying evaporative demand, and to monitor environmental parameters under forested conditions. These studies demonstrate the usefulness of automated measurements, and offer guidance for other researchers in developing inexpensive sensing and monitoring systems to further their research.
Evaluation of alternative methods for estimating reference evapotranspiration  [PDF]
Daniel K. Fisher, H. C. Pringle III
Agricultural Sciences (AS) , 2013, DOI: 10.4236/as.2013.48A008

Evapotranspiration is an important component in water-balance and irrigation scheduling models. While the FAO-56 Penman-Monteith method has become the de facto standard for estimating reference evapotranspiration (ETo), it is a complex method requiring several weather parameters. Required weather data are oftentimes unavailable, and alternative methods must be used. Three alternative ETo methods, the FAO-56 Reduced Set, Hargreaves, and Turc methods, were evaluated for use in Mississippi, a humid region of the USA, using only measurements of air temperature. The Turc equation, developed for use with measured temperature and solar radiation, was tested with estimated radiation and found to provide better estimates of FAO-56 ETo than the other methods. Mean bias errors of 0.75, 0.28, and -0.19 mm, mean absolute errors of 0.92, 0.68, and 0.62 mm, and percent errors of 22.5%, 8.5%, and -5.7% were found for daily estimates for the FAO-56 Reduced Set, Hargreaves, and Turc methods, respectively.

A Miniature Sensor for Measuring Reflectance, Relative Humidity, and Temperature: A Greenhouse Example  [PDF]
Reginald S. Fletcher, Daniel K. Fisher
Agricultural Sciences (AS) , 2018, DOI: 10.4236/as.2018.911106
Abstract: There is a growing interest in using miniature multi-sensor technology to monitor plant, soil, and environmental conditions in greenhouses and in field settings. The objectives of this study were to build a small multi-channel sensing system with ability to measure visible and near infrared light reflectance, relative humidity, and temperature, to test the light reflectance sensors for measuring spectral characteristics of plant leaves and soilless media, and to compare results of the relative humidity and temperature sensors to identical measurement obtained from a greenhouse sensor. The sensing system was built with off-the-shelf miniature multispectral spectrometers and relative humidity and temperature sensors. The spectrometers were sensitive to visible, red-edge, and near infrared light. The system was placed in a greenhouse setting and used to obtain relative reflectance measurements of plant leaves and soilless media and to record temperature and relative humidity conditions in the greenhouse. The spectrometer data obtained from plant leaf and soilless media were compatible with baseline spectral data collected with a hyperspectral spectroradiometer. The greenhouse was equipped with a relative humidity and temperature sensor. The relative humidity and temperature sensor measurements from our sensor system were strongly correlated with the relative humidity and temperature results obtained with the greenhouse sensors...
Irrigation Methods and Scheduling in the Delta Region of Mississippi: Current Status and Strategies to Improve Irrigation Efficiency  [PDF]
Hirut Kebede, Daniel K. Fisher, Ruixiu Sui, Krishna N. Reddy
American Journal of Plant Sciences (AJPS) , 2014, DOI: 10.4236/ajps.2014.520307
Abstract: Even though annual rainfall is high in the Delta region of Mississippi, only 30% occurs during the months in which the major crops are produced, making irrigation often necessary to meet crop water needs and to avoid risk of yield and profitability loss. Approximately, 65% of the farmland in this region is irrigated. The shallow Mississippi River Valley Alluvial Aquifer is the major source of water for irrigation and for aquaculture in the predominant catfish industry. This groundwater is being heavily used as row-crop irrigation has increased tremendously. Water level in this aquifer has declined significantly over the past twenty five years, with overdraft of approximately 370 million cubic meters of water per year. Moreover, the common irrigation practices in the Delta re-gion of Mississippi do not use water efficiently, further depleting the ground water and making ir-rigation more expensive to producers due to increasing energy prices. Irrigation experts in the re-gion have tested and verified various methods and tools that increase irrigation efficiency. This article presents a review of the current status of the irrigation practices in the Delta region of Mis-sissippi, and the improved methods and tools that are available to increase irrigation efficiency and to reduce energy costs for producers in the region as well as to stop the overdraft of the declining aquifer, ensuring its sustainable use.
Influence of Planting Date on Seed Protein, Oil, Sugars, Minerals, and Nitrogen Metabolism in Soybean under Irrigated and Non-Irrigated Environments  [PDF]
Nacer Bellaloui, Krishna N. Reddy, Anne M. Gillen, Daniel K. Fisher, Alemu Mengistu
American Journal of Plant Sciences (AJPS) , 2011, DOI: 10.4236/ajps.2011.25085
Abstract: Information on the effect of planting date and irrigation on soybean [Glycine max (L.) Merr.] seed composition in the Early Soybean Production System (ESPS) is deficient, and what is available is inconclusive. The objective of this research was to investigate the effects of planting date on seed protein, oil, fatty acids, sugars, and minerals in soybean grown under irrigated (I) and non-irrigated (NI) conditions. A 2-yr field experiment was conducted in Stoneville, MS in 2007 and 2008. Soybean was planted during second week of April (early planting) and second week of May (late planting) each year. Results showed that under irrigated condition, early planting increased seed oil (up to 16% increase) and oleic acid (up to 22.8% increase), but decreased protein (up to 6.6% decrease), linoleic (up to 10.9% decrease) and linolenic acids (up to 27.7% decrease) compared to late planting. Under I conditions, late planting resulted in higher sucrose and raffinose and lower stachyose compared with early planting. Under NI conditions, seed of early planting had higher protein (up to 4% increase) and oleic acid (up to 25% increase) and lower oil (up to10.8% decrease) and linolenic acids (up to 13% decrease) than those of late planting. Under NI, stachyose concentration was higher than sucrose or raffinose, especially in early planting. Under I, early planting resulted in lower leaf and seed B, Fe, and P concentrations compared with those of late planting. Under NI, however, early planting resulted in higher accumulation of leaf B and P, but lower seed B and P compared with those of late planting. This research demonstrated that both irrigation and planting date have a significant influence on seed protein, oil, unsaturated fatty acids, and sugars. Our results suggest that seed of late planting accumulate more B, P, and Fe than those of early planting, and this could be a beneficial gain. Limited translocation of nutrients from leaves to seed under NI is undesirable. Soybean producers may use this information to maintain yield and seed quality, and soybean breeders to select for seed quality traits and mineral translocation efficiency in stress environments.
Effect of Shade on Seed Protein, Oil, Fatty Acids, and Minerals in Soybean lines Varying in Seed Germinability in the Early Soybean Production System  [PDF]
Nacer Bellaloui, James R. Smith, Anne M. Gillen, Daniel K. Fisher, Alemu Mengistu
American Journal of Plant Sciences (AJPS) , 2012, DOI: 10.4236/ajps.2012.31008
Abstract: The cause of poor seed quality (germination) of soybean produced in the Early Soybean Production System in the midsouth U.S.A. is still not completely understood. Temperature, solar radiation, and soybean genotype may all be important factors involved. The objective of this research was to evaluate seed composition, mineral level, and nitrogen assimilation in high and low germinability soybean plant introductions in a full-sunlight (unshaded) and a low-light intensity (shaded) environments. Shade netting was employed in field plots that reduced light intensity by about 50% and air temperature by about 10?F/6?C (10%). A two-year field experiment was conducted on soybean accessions with high germinability (PI 587982A and PI 603723), low germinability (PI 80480 and PI 84976-1), and on soybean cultivars (DSR-3100 RR STS and Pella 86). Results showed that shade resulted in higher total oil, linoleic and linolenic acids, and lower protein and oleic acid. Shade also resulted in lower nitrogen assimilation, leaf chlorophyll concentration, but unshade resulted in higher total seed boron, iron, and nitrogen concentrations. Seed structural boron was positively correlated with germination and protein. Structural boron percentage was consistently higher under shade than under unshade in PI 80480, PI 84976-1, DSR-3100 RR STS, and Pella 86, but consistently higher under unshade than under shade in higher germinability lines PI 587982A and PI 603723, suggesting that different distribution mechanisms of structural boron exist between genotypes. The positive correlation between germination and structural B and between protein and structural B signify a possible role of B in seed quality traits. Our research demonstrated that light intensity, combined with temperature, can alter seed constituents. Higher germinability lines had higher germination rates and lower percentages of hardseededness, desirable traits for soybean seed.
Corn Yield Response to Reduced Water Use at Different Growth Stages  [PDF]
Hirut Kebede, Ruixiu Sui, Daniel K. Fisher, Krishna N. Reddy, Nacer Bellaloui, William T. Molin
Agricultural Sciences (AS) , 2014, DOI: 10.4236/as.2014.513139
To develop an efficient water use strategy for crop irrigation, we need to know how much water can be reduced without decreasing yield. A study was designed to determine corn growth stages at which water could be reduced without affecting grain yield, and at what soil moisture level water deficit stress begins in the plants in a silt loam soil. An experiment was conducted in a randomized complete block with a 3 × 4 factorial design in four replications, where treatments consisted of three soil moisture levels [100%, 75%, and 50% of field capacity (FC) of a silt loam soil by weight] and four growth stages [fourteen leaf stage (V14), silking (R1), milk (R3), and dent (R5) stages] in a greenhouse. Growth stages at the reproductive and grain fill stages of corn were selected because this study was intended for the Mississippi Delta, where there is frequent drought during these growth stages making irrigation necessary for corn production, whereas there is usually adequate rainfall during the vegetative growth stages. Results from this study showed that reducing soil moisture from 100% FC (fully irrigated) to 75% FC of a silt loam soil starting at the R1 growth stage in corn did not reduce yield significantly compared to yield from the 100% FC, while saving a significant amount of water. Physiological investigations at the three soil moisture treatments showed that a mild moisture deficit stress might have started at the 75% FC treatment. With further investigation, if savings in water at 75% FC result in a significant reduction in energy cost, it may be profitable to reduce soil moisture to 75% FC in a silt loam soil.
Development of an Open-Source Cloud-Connected Sensor-Monitoring Platform  [PDF]
Daniel K. Fisher, Reginald S. Fletcher, Saseendran S. Anapalli, H. C. Pringle III
Advances in Internet of Things (AIT) , 2018, DOI: 10.4236/ait.2018.81001
Abstract: Rapid advances in electronics and communications technologies offer continuously evolving options for sensing and awareness of the physical environment. Many of these advances are becoming increasingly available to “non-professionals,” that is, those without formal training or expertise in disciplines such as electronic engineering, computer programming, or physical sciences, via the open-source concept. The open-source concept of collaboration and sharing of ideas offers advantages including low cost, ease of use, extensive array of electronic technologies offered, and technical and programming support. Expansion of communications infrastructure, including wireless, cellular, and internet networks, continues to provide greater ability to be connected and share information over any distance in real time. A basic data-collection platform using open-source hardware and software and internet cloud components was developed and discussed. The simple and inexpensive platform was used to develop and implement an instrument system to remotely monitor soil-moisture status in agricultural fields. The monitoring system transferred data regularly from the field to an internet website via the cellular communications network. The system performed reliably over an entire growing season with no maintenance requirements. The basic platform can be modified to suit a user’s specific requirements, and offers options for automated collection, viewing, and sharing of remotely sensed data.
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