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Articles 1741 - 1770 of 6069
Full-Text Articles in Environmental Engineering
Historical Trends In Air Temperature, Precipitation, And Runoff Of A Plateau Inland River Watershed In North China, Along Zhang, Ruizhong Gao, Xixi Wang, Tingxi Liu, Lijing Fang
Historical Trends In Air Temperature, Precipitation, And Runoff Of A Plateau Inland River Watershed In North China, Along Zhang, Ruizhong Gao, Xixi Wang, Tingxi Liu, Lijing Fang
Civil & Environmental Engineering Faculty Publications
Understanding historical trends in temperature, precipitation, and runoff is important but incomplete for developing adaptive measures to climate change to sustain fragile ecosystems in cold and arid regions, including the Balagaer River watershed on the Mongolian Plateau of northeast China. The objective of this study was to detect such trends in this watershed from 1959 to 2017. The detection was accomplished using a Mann-Kendall sudden change approach at annual and seasonal time scales. The results indicated that the abrupt changes in temperature preceded that in either runoff or precipitation; these abrupt changes occurred between 1970 and 2004. Significant (α = …
Pfas Removals And Increases In The Effluent Of Thirteen New Hampshire Wastewater Treatment Facilities Due To The Effects Of Biological Treatment Processes, Zachary P. Harvell
Pfas Removals And Increases In The Effluent Of Thirteen New Hampshire Wastewater Treatment Facilities Due To The Effects Of Biological Treatment Processes, Zachary P. Harvell
Honors Theses and Capstones
PROPOSAL/ABSTRACT:
Perfluoroalkyl substances, or PFAS, are an emerging contaminant of concern in environmental engineering. This group of chemicals has been used by manufacturers since the 1940s due to their desirable waterproofing qualities. They also have a high chemical stability at high temperatures, which makes treatment difficult. A large variety of manufactured items contain PFAS, such as fabrics and apparel, non-stick items, and food wrappers. Recently, these compounds have come under question due to studies supporting harmful health effects, such as low birthweight, cancer, thyroid hormone disruption, and a weakened immune system. Due to their chemical structure, PFAS compounds are difficult …
A Review On Investigating The Experimental Process For Partial Replacement Of Cement With Sugarcane Bagasse In The Construction Industry, Amany G. Micheal Prof., Rania Rushdy Moussa Ass. Prof., Nadin Magdy Dawoud Eng.
A Review On Investigating The Experimental Process For Partial Replacement Of Cement With Sugarcane Bagasse In The Construction Industry, Amany G. Micheal Prof., Rania Rushdy Moussa Ass. Prof., Nadin Magdy Dawoud Eng.
Architectural Engineering
In the last few decades there has been speedily increasing in the agriculture and industrial wastes. This causes many environmental issues and raises the potential to contaminate the natural resources of living such as water, air and soil. Recently, the amount of organic waste produced daily has been rising, while it is poorly managed. It is either burned or disposed improperly, which effect negatively the environment and public health. On the other hand, during the cement production process many wastes, and pollutants are generated which have major negative impacts on the environment. Cement is considered as a substantial constituent of …
Selective Precipitation And Recovery Of Rare Earth Elements From Acid Mine Drainage, Robyn Lauren Christoferson
Selective Precipitation And Recovery Of Rare Earth Elements From Acid Mine Drainage, Robyn Lauren Christoferson
Graduate Theses, Dissertations, and Problem Reports (ETD)
The ability to secure rare earth elements (REEs) in the United States is of concern due to the rapid growth in demand and the monopolistic supply chain. The demand for REEs has skyrocketed in recent years due to the development of many green technologies. The United States and many other countries are currently reliant on China for REEs, who currently control greater than 90% of the global supply. Due to the severe impact of previous Chinese export quotas, it is important to lessen the reliance on importation and explore methods of recycling REEs from secondary sources. A secondary REE source …
Evaluation And Inter-Comparison Of Satellite Precipitation Estimations For Extreme Flood Events In Peninsular Malaysia, Zhen Xiang Eugene Soo
Evaluation And Inter-Comparison Of Satellite Precipitation Estimations For Extreme Flood Events In Peninsular Malaysia, Zhen Xiang Eugene Soo
Student Works (2020-2029)
Satellite precipitation products (SPP) have been useful in any hydrological applications as their extensive spatial coverage and finer space and time resolutions. However, these satellite estimations exhibit large systematic and random errors which may cause large uncertainties in any hydrological applications. In this study, three advanced satellite precipitation products, i.e. CMORPH, TRMM 3B42V7, and PERSIANN are utilized in conjunction with the ground observation to investigate their performance in detecting rain, capturing storms and rainfall pattern during extreme flood events. This study evaluates and compares the capability of the SPP by focusing on the 2014-2015 northeast monsoon extreme flood events. Three …
Site-Specific Irrigation Management In A Sub-Humid Climate Using A Spatial Evapotranspiration Model With Satellite And Airborne Imagery, Sandeep Bhatti, Derek M. Heeren, J. Burdette Barker, Christopher M. U. Neale, Wayne Woldt, Mitchell S. Maguire, Daran Rudnick
Site-Specific Irrigation Management In A Sub-Humid Climate Using A Spatial Evapotranspiration Model With Satellite And Airborne Imagery, Sandeep Bhatti, Derek M. Heeren, J. Burdette Barker, Christopher M. U. Neale, Wayne Woldt, Mitchell S. Maguire, Daran Rudnick
Department of Agricultural and Biological Systems Engineering: Faculty Publications
Variable Rate Irrigation (VRI) considers spatial variability in soil and plant characteristics to optimize irrigation management in agricultural fields. The advent of unmanned aircraft systems (UAS) creates an opportunity to utilize high-resolution (spatial and temporal) imagery into irrigation management due to decreasing costs, ease of operation, and reduction of regulatory constraints. This research aimed to evaluate the use of UAS data for VRI, and to quantify the potential of VRI in terms of relative crop and water response. Irrigation treatments were: (1) VRI using Landsat imagery (VRI-L), (2) VRI using UAS imagery (VRI-U), (3) uniform (U), and (4) rainfed (R). …
Calibration Of A Common Shortwave Multispectral Camera System For Quantitative Agricultural Applications, J. Burdette Barker, Wayne Woldt, Brian Wardlow, Christopher Michael Usher Neale, Mitchell S. Maguire, Bryan Leavitt, Derek M. Heeren
Calibration Of A Common Shortwave Multispectral Camera System For Quantitative Agricultural Applications, J. Burdette Barker, Wayne Woldt, Brian Wardlow, Christopher Michael Usher Neale, Mitchell S. Maguire, Bryan Leavitt, Derek M. Heeren
Department of Agricultural and Biological Systems Engineering: Faculty Publications
Unmanned aerial systems (UAS) for collecting multispectral imagery of agricultural fields are becoming more affordable and accessible. However, there is need to validate calibration of sensors on these systems when using them for quantitative analyses such as evapotranspiration, and other modeling for agricultural applications. The results of laboratory testing of a MicaSense (Seattle, WA, USA) RedEdge™ 3 multispectral camera and MicaSense Downwelling Light Sensor (irradiance sensor) system using a calibrated integrating sphere were presented. Responses of the camera and irradiance sensor were linear over many light levels and became non-linear at light levels below expected real-world, field conditions. Simple linear …
An Automated Seepage Meter For Streams And Lakes, D. Kip Solomon, Eric Humphrey, Troy E. Gilmore, David P. Genereux, Vitaly Zlotnik
An Automated Seepage Meter For Streams And Lakes, D. Kip Solomon, Eric Humphrey, Troy E. Gilmore, David P. Genereux, Vitaly Zlotnik
Department of Agricultural and Biological Systems Engineering: Faculty Publications
We describe a new automatic seepage meter for use in soft bottom streams and lakes. The meter utilizes a thin‐walled tube that is inserted into the streambed or lakebed. A hole in the side of the tube is fitted with an electric valve. Prior to the test, the valve is open and the water level inside the tube is the same as the water level outside the tube. The test starts with closure of the valve, and the water level inside the tube changes as it moves toward the equilibrium hydraulic head that exists at the bottom of the tube. …
Influence Of Setback Distance On Antibiotics And Antibiotic Resistance Genes In Runoff And Soil Following The Land Application Of Swine Manure Slurry, Maria C. Hall, Noelle Mware, John E. Gilley, Shannon L. Bartelt-Hunt, Daniel D. Snow, Amy M. Schmidt Schmidt, Kent M. Eskridge, Xu Li
Influence Of Setback Distance On Antibiotics And Antibiotic Resistance Genes In Runoff And Soil Following The Land Application Of Swine Manure Slurry, Maria C. Hall, Noelle Mware, John E. Gilley, Shannon L. Bartelt-Hunt, Daniel D. Snow, Amy M. Schmidt Schmidt, Kent M. Eskridge, Xu Li
Department of Agricultural and Biological Systems Engineering: Faculty Publications
The environmental spread of antibiotics and antibiotic resistance genes (ARGs) from the land application of livestock wastes can be a potential public health threat. The objective of this study was to assess the effects of setback distance, which determines how close manure may be applied in relation to surface water, on the transport of antibiotics and ARGs in runoff and soil following land application of swine manure slurry. Rainfall simulation tests were conducted on field plots covered with wheat residues, each of which contained an upslope manure region where slurry was applied and an adjacent downslope setback region that did …
Evaluation Of Low-Cost Depth Cameras For Agricultural Applications, Isabella C.F.S. Condotta, T. M. Brown-Brandl, Santosh Pitla, John P. Stinn, Késia O. Silva-Miranda
Evaluation Of Low-Cost Depth Cameras For Agricultural Applications, Isabella C.F.S. Condotta, T. M. Brown-Brandl, Santosh Pitla, John P. Stinn, Késia O. Silva-Miranda
Department of Agricultural and Biological Systems Engineering: Faculty Publications
Low-cost depth-cameras have been used in many agricultural applications with reported advantages of low cost, reliability and speed of measurement. However, some problems were also reported and seem to be technology- related, so understanding the limitations of each type of depth camera technology could provide a basis for technology selection and the development of research involving its use. The cameras use one or a combination of two of the three available technologies: structured light, time-of-flight (ToF), and stereoscopy. The objectives were to evaluate these different technologies for depth sensing, including measuring accuracy and repeatability of distance data and measurements at …
Classification Of Tactile And Motor Velocity-Evoked Hemodynamic Response In Primary Somatosensory And Motor Cortices As Measured By Functional Near-Infrared Spectroscopy, Mohsen Hozan, Jacob Greenwood, Michaela Sullivan, Steven M. Barlow
Classification Of Tactile And Motor Velocity-Evoked Hemodynamic Response In Primary Somatosensory And Motor Cortices As Measured By Functional Near-Infrared Spectroscopy, Mohsen Hozan, Jacob Greenwood, Michaela Sullivan, Steven M. Barlow
Department of Agricultural and Biological Systems Engineering: Faculty Publications
Functional near-infrared spectroscopy (fNIRS) is an emerging technique in studying cerebral hemodynamics; however, consensus on the analysis methods and the clinical applications has yet to be established. In this study, we demonstrate the results of a pilot fNIRS study of cerebral hemodynamic response (HR) evoked by pneumotactile and sensorimotor stimuli on the dominant hand. Our goal is to find the optimal stimulus parameters to maximally evoke HR in the primary somatosensory and motor cortices. We use a pulsatile pneumatic array of 14 tactile cells that were attached to the glabrous surface of the dominant hand, with a patterned stimulus that …
Rapeseed Stand Count Estimation At Leaf Development Stages With Uav Imagery And Convolutional Neural Networks, Biquan Zhao, Chenghai Yang, Yeyin Shi, Qingxi Liao, Guangsheng Zhou, Chufeng Wang, Tianjin Xie, Zhao Jiang, Dongyan Zhang, Wanneng Yang, Chenglong Huang, Jing Xie, Jian Zhang
Rapeseed Stand Count Estimation At Leaf Development Stages With Uav Imagery And Convolutional Neural Networks, Biquan Zhao, Chenghai Yang, Yeyin Shi, Qingxi Liao, Guangsheng Zhou, Chufeng Wang, Tianjin Xie, Zhao Jiang, Dongyan Zhang, Wanneng Yang, Chenglong Huang, Jing Xie, Jian Zhang
Department of Agricultural and Biological Systems Engineering: Faculty Publications
Rapeseed is an important oil crop in China. Timely estimation of rapeseed stand count at early growth stages provides useful information for precision fertilization, irrigation, and yield prediction. Based on the nature of rapeseed, the number of tillering leaves is strongly related to its growth stages. However, no field study has been reported on estimating rapeseed stand count by the number of leaves recognized with convolutional neural networks (CNNs) in unmanned aerial vehicle (UAV) imagery. The objectives of this study were to provide a case for rapeseed stand counting with reference to the existing knowledge of the number of leaves …
Automatic Wheat Lodging Detection And Mapping In Aerial Imagery To Support High-Throughput Phenotyping And In-Season Crop Management, Biquan Zhao, Jiating Li, P. Stephen Baenziger, Vikas Belamkar, Yufeng Ge, Jian Zhang, Yeyin Shi
Automatic Wheat Lodging Detection And Mapping In Aerial Imagery To Support High-Throughput Phenotyping And In-Season Crop Management, Biquan Zhao, Jiating Li, P. Stephen Baenziger, Vikas Belamkar, Yufeng Ge, Jian Zhang, Yeyin Shi
Department of Agricultural and Biological Systems Engineering: Faculty Publications
Latest advances in unmanned aerial vehicle (UAV) technology and convolutional neural networks (CNNs) allow us to detect crop lodging in a more precise and accurate way. However, the performance and generalization of a model capable of detecting lodging when the plants may show different spectral and morphological signatures have not been investigated much. This study investigated and compared the performance of models trained using aerial imagery collected at two growth stages of winter wheat with different canopy phenotypes. Specifically, three CNN-based models were trained with aerial imagery collected at early grain filling stage only, at physiological maturity only, and at …
Antibiotic Resistance Gene Profile Changes In Cropland Soil After Manure Application And Rainfall, Morgan A. Meyers, Lisa M. Durso, John E. Gilley, Heidi Waldrip, Lana Castleberry, Amy Schmidt
Antibiotic Resistance Gene Profile Changes In Cropland Soil After Manure Application And Rainfall, Morgan A. Meyers, Lisa M. Durso, John E. Gilley, Heidi Waldrip, Lana Castleberry, Amy Schmidt
Department of Agricultural and Biological Systems Engineering: Faculty Publications
Land application of manure introduces gastrointestinal microbes into the environ- ment, including bacteria carrying antibiotic resistance genes (ARGs). Measuring soil ARGs is important for active stewardship efforts to minimize gene flow from agri- cultural production systems; however, the variety of sampling protocols and target genes makes it difficult to compare ARG results between studies. We used polymerase chain reaction (PCR) methods to characterize and/or quantify 27 ARG targets in soils from 20 replicate, long-term no-till plots, before and after swine manure application and simulated rainfall and runoff. All samples were negative for the 10 b-lactamase genes assayed. For tetracycline resistance, …
Setback Distance Impacts On Transport And Antibiotic Resistance Phenotypes Of Fecal Indicators, Morgan A. Meyers, Lisa M. Durso, John E. Gilley, Daniel N. Miller, Xu Li, Amy M. Schmidt Schmidt
Setback Distance Impacts On Transport And Antibiotic Resistance Phenotypes Of Fecal Indicators, Morgan A. Meyers, Lisa M. Durso, John E. Gilley, Daniel N. Miller, Xu Li, Amy M. Schmidt Schmidt
Department of Agricultural and Biological Systems Engineering: Faculty Publications
Although the land application of livestock manure has numerous agronomic benefits, runoff from manured fields can degrade water quality. Setbacks instruct a minimum distance be maintained between manure application and surface waters. They are commonly used to manage nutrient contamination of surface waters; however, their utility for reducing microbial inputs remains unclear. Here we evaluated the efficacy of five setback distances in no-till wheat (Triticum aes- tivum L.) residue plots for reducing runoff fecal indicator concentrations from swine manure-amended fields. Also, since there is increasing interest in the use of water quality indicators to monitor antibiotic resistance in environmental sys- …
Innovative Extension Methods In The U.S. To Promote Irrigation Water Management, Daran Rudnick, Matt Stockton, Saleh Taghvaeian, Jason Warren, Michael D. Dukes, Amy Kremen, Christopher G. Henry, Jonathan Aguilar, Brenda Ortiz, Allan A. Andales, Chuck A. Burr, Xin Qiao, Wei‑Zhen Liang, Steven Walthour, Steve H. Amosson
Innovative Extension Methods In The U.S. To Promote Irrigation Water Management, Daran Rudnick, Matt Stockton, Saleh Taghvaeian, Jason Warren, Michael D. Dukes, Amy Kremen, Christopher G. Henry, Jonathan Aguilar, Brenda Ortiz, Allan A. Andales, Chuck A. Burr, Xin Qiao, Wei‑Zhen Liang, Steven Walthour, Steve H. Amosson
Department of Agricultural and Biological Systems Engineering: Faculty Publications
Promotion and adoption of irrigation water management (IWM) technology, tools, and best management practices are important as water availability concerns are addressed. Traditional extension programs have relied on lecture presentations, field tours, fact sheets, and on-station demonstrations to promote IWM practices and tools. However, these platforms tend not to provide the experience and opportunity for growers to identify and become comfortable with innovative solutions, such as new technology. To address these challenges and to appeal to an ever-changing client base, innovative and locally relevant extension and outreach programs have been devised to engage and educate growers. This article describes some …
Soil-Water-Energy Nexus Of Green Roofs, Katherine Ann Bartels
Soil-Water-Energy Nexus Of Green Roofs, Katherine Ann Bartels
Masters Theses
"As the urban landscape continues to sprawl into previously undeveloped land to accommodate population growth, the need to design cities that effectively manage urban stormwater is imperative for a sustainable future. Green roofs use rain-harvesting techniques to reduce urban stormwater discharge while simultaneously providing traditional roof services as well as several ecosystem services. However, green roof media design varies greatly among commercial applications, and little guidance is available to engineers when selecting the media for prospective green roofs. Efforts to maximize stormwater retention and enhance urban heat island mitigation capabilities of green roofs while concurrently reducing nutrient loading were examined …
Emulsion Characterization Study For Improved Bilgewater Treatment And Management, Daniela Diaz Hernandez
Emulsion Characterization Study For Improved Bilgewater Treatment And Management, Daniela Diaz Hernandez
Electronic Theses and Dissertations, 2020-2023
The need for proper management of bilgewater to meet discharge regulations (e.g., 15 ppm oil) has revealed the necessity to expand the current understanding of bilgewater emulsions. This study proposed to evaluate emulsion stability under various environmental conditions and to identify governing parameters for emulsion formation. The stabilizing properties of eight-commercial cleaners and two-neat surfactants were evaluated. In situ characterization techniques were used for monitoring emulsion stability. Additionally, a needle-type pH microsensor and fluorescence spectroscopy were used for analyzing mass transfer at the oil-water interface. Water quality of extracted bilgewater showed to highly vary between vessels (e.g., conductivity: 1.74 -- …
การเปรียบเทียบการถ่ายเทมวลสารและพลังงานที่ใช้ในการดำเนินระบบของคอลัมน์แบบฟองอากาศและคอลัมน์แบบบรรจุตัวกลาง, นวพัฒน์ เตชะธางกูร
การเปรียบเทียบการถ่ายเทมวลสารและพลังงานที่ใช้ในการดำเนินระบบของคอลัมน์แบบฟองอากาศและคอลัมน์แบบบรรจุตัวกลาง, นวพัฒน์ เตชะธางกูร
Chulalongkorn University Theses and Dissertations (Chula ETD)
นวิจัยนี้เป็นการศึกษาการถ่ายเทมวลสารของแก๊สออกซิเจนจากวัฏภาคแก๊สไปสู่น้ำประปาที่เป็นวัฏภาคของเหลวด้วยคอลัมน์สามประเภท คือ คอลัมน์แบบฟองอากาศ คอลัมน์แบบฟองอากาศชนิดเติมตัวกลาง และคอลัมน์แบบบรรจุตัวกลาง โดยทุกคอลัมน์มีเส้นผ่านศูนย์กลาง 20 ซม. และความสูง 80 ซม. ทั้งนี้ การทดลองจะแบ่งเป็น 4 ส่วน โดยในส่วนแรกเป็นการทดลองในคอลัมน์แบบฟองอากาศที่ใช้อัตราการไหลของแก๊สและของเหลวที่แตกต่างกันในหัวจ่ายอากาศขนาด 0.4, 0.8, และ 1.2 มม. ที่มีจำนวน 19 และ 38 รู ซึ่งพบว่า การเพิ่มขึ้นของอัตราการไหลของแก๊สส่งผลให้การถ่ายเทมวลสารเพิ่มขึ้น โดยที่หัวจ่ายอากาศขนาด 0.4 มม. มีค่าการถ่ายเทมวลสารสูงที่สุด นอกจากนี้ การเพิ่มจำนวนรูของหัวจ่ายอากาศส่งผลให้ฟองอากาศมีขนาดเล็กและมีความเร็วในการลอยตัวช้าลง เป็นผลให้มีสัดส่วนของแก๊สและพื้นที่ผิวจำเพาะในการถ่ายเทมวลสารเพิ่มขึ้น ส่งผลให้มีการถ่ายเทมวลสารมากขึ้น แต่อย่างไรก็ตาม การใช้พลังงานของหัวจ่ายขนาดเล็กจะสิ้นเปลืองมากที่สุดในการเดินระบบ การทดลองในส่วนที่ 2 เป็นการทดลองในคอลัมน์แบบฟองอากาศชนิดตัวตัวกลาง โดยเติมตัวกลางทั้งหมด 4 ชนิด คือ พอลล์ริง แคสเคดมินิริง อานม้าและแรสชิกริง ที่มีขนาดและเติมในปริมาตรที่แตกต่างกัน โดยพบว่า ตัวกลางพอล์ลริงขนาด 25 มม. ในปริมาตร 2.5% จะสามารถช่วยเพิ่มประสิทธิภาพให้เกิดการถ่ายเทมวลสาร เมื่อใช้ตัวกลางกับหัวจ่ายอากาศขนาดใหญ่ แต่เมื่อใช้ตัวกลางกับหัวจ่ายอากาศขนาดเล็กจะทำให้มีค่าการถ่ายเทมวลสารลดลง ในการทดลองส่วนที่ 3 ได้ทำการทดลองการถ่ายเทมวลสารในคอลัมน์แบบบรรจุตัวกลาง โดยพบว่า การเพิ่มอัตราการไหลของเหลวมีผลทำให้มีการถ่ายเทมวลสารดีขึ้น และตัวกลางพอลล์ริงขนาด 50 มม. สามารถทำให้เกิดการถ่ายเทมวลสารดีที่สุด นอกจากนี้เมื่อทำการเปรียบเทียบกันแล้วนั้น คอลัมน์แบบบรรจุตัวกลางมีความสามารถในการถ่ายเทมวลสารน้อยกว่าแบบเป่าฟองอากาศ แต่มีการใช้พลังงานน้อยกว่า โดยเมื่อนำสภาวะการดำเนินการที่ดีที่สุดของแต่ละคอลัมน์ไปทำการทดสอบการดูดซึมสารเบนซีนในการทดลองที่ 4 พบว่าคอลัมน์แบบฟองอากาศสามารถบำบัดสารอินทรีย์ระเหยง่ายได้ดีที่สุด ประมาณ 43– 75% แต่มีการใช้พลังงานที่ใช้ในระบบที่มากที่สุดเช่นเดียวกัน
ผลของความเค็มและไนเตรทต่อระดับสุขภาพในปะการังเขากวาง (Acropora Sp.) ปะการังจาน (Turbinaria Sp.) และปะการังโขด (Porites Sp.), กฤติญา สำราญศิลป์
ผลของความเค็มและไนเตรทต่อระดับสุขภาพในปะการังเขากวาง (Acropora Sp.) ปะการังจาน (Turbinaria Sp.) และปะการังโขด (Porites Sp.), กฤติญา สำราญศิลป์
Chulalongkorn University Theses and Dissertations (Chula ETD)
ชุมชนตามแนวชายฝั่งที่มีการอยู่อาศัยอย่างหนาแน่นถือเป็นแหล่งกำเนิดหลักของมลพิษทางทะเลและชายฝั่ง โดยชุมชนจะปลดปล่อยน้ำเสียชุมชนลงสู่ทะเลโดยไม่มีการบำบัด นอกจากนั้นการเปลี่ยนแปลงของฤดูกาลยังเพิ่มความรุนแรงของปัญหาน้ำเสียชุมชนได้ เช่น ในฤดูฝน ปริมาณน้ำฝนที่เกิดขึ้นทำให้ความเค็มน้ำทะเลลดลง พร้อมทั้งเกิดการเติมธาตุอาหารสู่ทะเลจากการชะหน้าดินจากน้ำท่า ส่งผลให้คุณภาพน้ำทะเลโดยรอบเสื่อมลง และนำไปสู่การเสื่อมโทรมในชุมชนปะการังโดยรอบแนวชายฝั่ง ดังนั้นวัตถุประสงค์ของงานวิจัยนี้คือ เพื่อศึกษาผลของความเค็มและไนเตรทต่อระดับสุขภาพปะการังเขากวาง (Acropora sp.) ปะการังจาน (Turbinaria sp.) และปะการังโขด (Porites sp.) ที่ความเค็ม 15 20 25 และ 30 พีเอสยู ร่วมกับความเข้มข้น ไนเตรท 5 20 60 และ 100 ไมโครกรัมไนโตรเจนต่อลิตร ทำการทดลองความเข้มข้นละ 3 ซ้ำ โดยประเมินสุขภาพของปะการังโดยใช้แผนภูมิปะการัง ความหนาแน่นสาหร่ายซูแซนเทลลีและปริมาณคลอโรฟิลล์ เอ และร้อยละการยืดโพลิป โดยปะการังจะที่มีร้อยละสุขภาพเสื่อมโทรมมากกว่าร้อยละ 50 จะสามารถคำนวณหาความเป็นพิษเฉียบพลันของไนเตรท หรือ LC50 ด้วยการวิเคราะห์แบบโพรบิทได้ ผลการศึกษาพบว่าที่ความเค็ม 15 พีเอสยู และที่ไนเตรท 100 ไมโครกรัมไนโตรเจนต่อลิตร ส่งผลให้ปะการังมีความเสื่อมโทรมมากที่สุด ในทั้งปะการัง 3 ชนิด โดยที่สภาะวะดังกล่าว ปะการังเขากวางมี LC50 ของไนเตรท ที่เวลา 96 ชั่วโมง มีค่าเท่ากับ 94.46 ไมโครกรัมไนโตรเจนต่อลิตร ปะการังเขาโขดมี LC50 ที่เวลา 120 ชั่วโมง มีค่าเท่ากับ 106.35 ไมโครกรัมไนโตรเจนต่อลิตร และปะการังจานมี LC50 ที่เวลา 144 ชั่วโมง มีค่าเท่ากับ 116.55 ไมโครกรัมไนโตรเจนต่อลิตร นอกจากนั้นยังยืนยันการเพิ่มขึ้นของร้อยละการเสื่อมโทรมได้จากการเพิ่มขึ้นของความหนาแน่นสาหร่าย ซูแซนเทลลีและปริมาณคลอโรฟิลล์ เอ ที่พบในตู้ทดลอง ผลการศึกษาคุณภาพน้ำทะเลรอบเกาะสีชัง ในปี 2559-2561 พบว่าอิทธิพลของฤดูฝนทำให้ความเค็มของน้ำทะเลและปริมาณออกซิเจนละลายลดลง และมีปริมาณไนเตรทเพิ่มสูงขึ้นโดยรอบเกาะสีชัง โดยเฉพาะในบริเวณที่มีชุมชนหนาแน่นเช่น ท่าเทววงษ์ พบว่ามีคุณภาพน้ำทะเลต่ำที่สุด ซึ่งผลการศึกษานี้สามารถนำไปใช้ในการเฝ้าระวังคุณภาพน้ำทะเลรอบเกาะสีชังและใช้ประกอบการบริหารจัดการสิ่งแวดล้อมบนเกาะสีชังได้ภายในอนาคต
Metalimnetic Oxygen Minimum In Green Lake, Wisconsin, Mahta Naziri Saeed
Metalimnetic Oxygen Minimum In Green Lake, Wisconsin, Mahta Naziri Saeed
Dissertations, Master's Theses and Master's Reports
Green Lake, located in Green Lake County, Wisconsin, has been experiencing summer Metalimnetic Oxygen Minima (MOM). The severity of the MOM has increased in recent years and the lake was listed as impaired in 2014. To investigate the MOM, the lake was monitored during 2017 and 2018 at two sites using moored temperature and oxygen sensors recording at 1-hour intervals. Using these data, a hydrodynamic model (Simstrat) was configured for the lake. A new model was then developed to simulate the oxygen changes in the lake. Productivity, respiration, sediment oxygen demand (SOD) and fluxes were included, and hydrodynamics were driven …
Systems Analysis For Sustainability Assessment Of Biogas And Bio-Ch4 Production From Food Waste And Dairy Manure Mixtures In The Us, Sharath Kumar Ankathi
Systems Analysis For Sustainability Assessment Of Biogas And Bio-Ch4 Production From Food Waste And Dairy Manure Mixtures In The Us, Sharath Kumar Ankathi
Dissertations, Master's Theses and Master's Reports
The purpose of the dissertation is to relate systems analysis for bioenergy to identify optimum configurations for improved scenarios and to make better decisions in a systems perspective.
Chapter 1 is a review of the literature to identify the state of the knowledge in terms of systems analysis for anaerobic digestion (AD) bioenergy systems. The key outcomes from this review showed that anaerobic digestion of mixtures of food waste and animal manure has great potential to achieve economic and environmental benefits compared to other treatments of organic waste materials, such as landfilling or conventional manure management.
Chapter 2 focuses on …
Mechanisms Of Pathogen Inactivation In Wastewater And Pharmaceutical Applications, Christa L. Meingast
Mechanisms Of Pathogen Inactivation In Wastewater And Pharmaceutical Applications, Christa L. Meingast
Dissertations, Master's Theses and Master's Reports
Infectious diseases are a significant threat to public health. Though society enacts practices to prevent the spread of these dangerous diseases, challenges remain. Therefore, continual advancements in treatment and prevention are required. Wastewater treatment and viral clearance in pharmaceutical applications are two key health measures that prevent the spread of infections.
A low-cost, low-technology biosolids treatment process was developed to improve wastewater treatment by collecting key information on storage temperature, ammonia, volatile solids, moisture content, pH, and pathogen inactivation in biosolids over long-term storage at two wastewater treatment plants located in northern climates of the United States. Inactivation of pathogens …
Towards Efficient Water Treatment: Mechanism Of Colloidal Fouling Of Ultrafiltration Membranes, Ikenna Henry Ozofor
Towards Efficient Water Treatment: Mechanism Of Colloidal Fouling Of Ultrafiltration Membranes, Ikenna Henry Ozofor
Dissertations, Master's Theses and Master's Reports
This research study first reviewed challenges of conventional and membrane separation systems for water treatment. Though membrane separation systems appeared superior to the conventional counterparts for water and wastewater treatment, wider applications of membrane systems have been limited by some factors, most notably is membrane fouling. Experimental studies were therefore conducted to achieve the goal of this research, which is to investigate how feed properties affect fouling of ultrafiltration (UF) membranes by colloids.
Feed salinity, pH, and nanoparticle concentration were the variables studied to unravel how different UF membranes are fouled by model silica colloids (with average diameter of 25nm). …
Deep Learning Predicts Microbial Interactions From Self-Organized Spatiotemporal Patterns, Joon-Yong Lee, Natalie C. Sadler, Robert G. Egbert, Christopher R. Anderton, Kirsten S. Hofmockel, Janet K. Jansson, Hyun-Seob Song
Deep Learning Predicts Microbial Interactions From Self-Organized Spatiotemporal Patterns, Joon-Yong Lee, Natalie C. Sadler, Robert G. Egbert, Christopher R. Anderton, Kirsten S. Hofmockel, Janet K. Jansson, Hyun-Seob Song
Department of Agricultural and Biological Systems Engineering: Faculty Publications
Microbial communities organize into spatial patterns that are largely governed by interspecies interactions. This phenomenon is an important metric for understanding community functional dynamics, yet the use of spatial patterns for predicting microbial interactions is currently lacking. Here we propose supervised deep learning as a new tool for network inference. An agent-based model was used to simulate the spatiotemporal evolution of two interacting organisms under diverse growth and interaction scenarios, the data of which was subsequently used to train deep neural networks. For small-size domains (100 mm x 100 mm) over which interaction coefficients are assumed to be invariant, we …
Ground And Aerial Robots For Agricultural Production: Opportunities And Challenges, Santosh Pitla, Sreekala Bajwa, Santosh Bhusal, Tom Brumm, Tami M. Brown-Brandl, Dennis R. Buckmaster, Isabella Condotta, John Fulton, Todd J. Janzen, Manoj Karkee, Mario Lopez, Robert Moorhead, Michael Sama, Leon Schumacher, Scott Shearer, Alex Thomasson
Ground And Aerial Robots For Agricultural Production: Opportunities And Challenges, Santosh Pitla, Sreekala Bajwa, Santosh Bhusal, Tom Brumm, Tami M. Brown-Brandl, Dennis R. Buckmaster, Isabella Condotta, John Fulton, Todd J. Janzen, Manoj Karkee, Mario Lopez, Robert Moorhead, Michael Sama, Leon Schumacher, Scott Shearer, Alex Thomasson
Department of Agricultural and Biological Systems Engineering: Faculty Publications
Crop and animal production techniques have changed significantly over the last century. In the early 1900s, animal power was replaced by tractor power that resulted in tremendous improvements in field productivity, which subsequently laid foundation for mechanized agriculture. While precision agriculture has enabled site-specific management of crop inputs for improved yields and quality, precision livestock farming has boosted efficiencies in animal and dairy industries. By 2020, highly automated systems are employed in crop and animal agriculture to increase input efficiency and agricultural output with reduced adverse impact on the environment. Ground and aerial robots combined with artificial intelligence (AI) techniques …
Control Of Energy Storage Utilisation For A Building Integrated Microgrid Using Multi-Objective Metaheuristic Optimisation Methods, Quang An Phan
Control Of Energy Storage Utilisation For A Building Integrated Microgrid Using Multi-Objective Metaheuristic Optimisation Methods, Quang An Phan
Theses
The aim of this thesis was to develop and analyse optimisation strategies for commercial buildings with integrated microgrids, in order to find optimal trade-offs between maximising profitability and facilitating renewable energy from the national power grid. The continued proliferation of microgrids, as well as the increase in electricity produced by renewable energy sources on the Irish national grid has necessitated the requirement for these strategies. Models to simulate the performance of a photovoltaic system, wind turbine and battery bank were developed and validated. The most suitable optimisation algorithm to generate an optimal charge/discharge rate schedule for a battery bank was …
Innovative Fe(Iii)-Dosed Anaerobic Biological Treatment System: From Fe And S Biogeochemical Reactions To Engineering Process, Musfique Ahmed
Innovative Fe(Iii)-Dosed Anaerobic Biological Treatment System: From Fe And S Biogeochemical Reactions To Engineering Process, Musfique Ahmed
Graduate Theses, Dissertations, and Problem Reports (ETD)
In moving toward more sustainable wastewater management, anaerobic treatment is gaining increasing popularity due to its simplicity, low energy requirement, low sludge production and less emission of greenhouse gases compared to typical aerobic wastewater treatment systems. Electron acceptors such as nitrate, sulfate, and CO2 have been used in various anaerobic processes for removal of organic matters from wastewater under anoxic or anaerobic environments. In energy producing regions, ferric iron, Fe(III), is a predominant element in iron containing wastes such as acid mine drainage (AMD) and coal ash, which can potentially be used as a source of iron in novel …
Adapting To Extreme Heat: Social, Atmospheric, And Infrastructure Impacts Of Air Conditioning In Megacities - The Case Of New York City, Harold Gamarro
Adapting To Extreme Heat: Social, Atmospheric, And Infrastructure Impacts Of Air Conditioning In Megacities - The Case Of New York City, Harold Gamarro
Dissertations and Theses
Extreme heat events are becoming more frequent and intense in most large cities. Built-up surfaces also limit cooling mechanisms, leading to warmer conditions in cities, a phenomenon called the Urban Heat Island (UHI). This presents major challenges to reduce adverse health effects of hot weather, particularly in vulnerable populations like the elderly and low-income communities. Here we explore the overall impacts of increasing air conditioning (AC) system adoption in residences as an adaptive measure to reduce human health risks under heat waves, with New York City (NYC) as a case study. This study uses AC adoption data from the 2017 …
An Evaluation Of Ground-Freezing Methods In The Zone Of Discontinuous Permafrost, Northwest Territories, Elzbieta Mastej Ms
An Evaluation Of Ground-Freezing Methods In The Zone Of Discontinuous Permafrost, Northwest Territories, Elzbieta Mastej Ms
Theses and Dissertations (Comprehensive)
Northwestern Canada is one of the most rapidly warming regions on Earth. The southern limit of the discontinuous permafrost zone is highly sensitive to small climatic fluctuations and presently experiencing a rapid landscape change due to accelerated permafrost thaw, which is further exacerbated by anthropogenic disturbances such as seismic exploration. Recent research has begun to examine both natural and mechanical approaches to minimize permafrost loss, although the utility of such methods in peatland environments is not well understood. This study explored the efficiency of natural and artificial ground cooling processes in a peatland environment by evaluating snow exclusion and thermosyphon …