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Articles 89221 - 89250 of 197251

Full-Text Articles in Engineering

Analysis Of A Joined Split-Ring Fss Structure Characterized By Three Resonant Frequencies And A Tuned Enhanced Band Using The Wcip Method, Manel Aouissi, Mohammed Titaouine, Thayuan Rolim De Sousa, Ibtissem Adoui, Alfredo Gomes Neto, Henri Baudrand Jan 2017

Analysis Of A Joined Split-Ring Fss Structure Characterized By Three Resonant Frequencies And A Tuned Enhanced Band Using The Wcip Method, Manel Aouissi, Mohammed Titaouine, Thayuan Rolim De Sousa, Ibtissem Adoui, Alfredo Gomes Neto, Henri Baudrand

Turkish Journal of Electrical Engineering and Computer Sciences

This work presents the analysis of a joined split-ring frequency selective surface (FSS) for X-band applications using the wave concept iterative procedure (WCIP). When the incident normal plane wave is polarized in the $x$ direction, the joined split-ring FSS shows three rejecting bands at 9 GHz, 10.5 GHz, and 11.5 GHz simultaneously with bandwidths of 3.11 GHz, 0.6 GHz, and 1.13 GHz, respectively. Moreover, one rejecting band at 6.5 GHz is present when the FSS is fed with a normal plane excited in the $y$ direction. In addition, the different resonant frequencies can be tuned independently to give rise to …

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K-Nn-Based Classification Of Sleep Apnea Types Using Ecg, Oğuz Han Ti̇muş, Emi̇ne Doğru Bolat Jan 2017

K-Nn-Based Classification Of Sleep Apnea Types Using Ecg, Oğuz Han Ti̇muş, Emi̇ne Doğru Bolat

Turkish Journal of Electrical Engineering and Computer Sciences

Obstructive sleep apnea syndrome (OSAS) is a common sleep disorder that yields cardiovascular diseases, excessive daytime sleepiness, and poor quality of life if not treated. Classification of OSAS from electrocardiograms (ECGs) is a noninvasive method and much more affordable than traditional methods. This study proposes a pattern recognition system for automated apnea diagnosis based on heart rate variability (HRV) and ECG-derived respiratory signals. The k-nearest neighbor (k-NN) classifier has been used to develop the models for classifying the sleep apnea types. For comparison purposes, classification models based on multilayer perceptron, support vector machines, and C4.5 decision tree (C4.5 DT) have …

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Analytical Modeling Of A Coaxial Cylindrical Probe Capacitive Sensor Based On Matlab/Simulink For Conductive Liquids Level Measurements, Majid Toghyani Rizi, Mohammad Hadi Shahrokh Abadi Jan 2017

Analytical Modeling Of A Coaxial Cylindrical Probe Capacitive Sensor Based On Matlab/Simulink For Conductive Liquids Level Measurements, Majid Toghyani Rizi, Mohammad Hadi Shahrokh Abadi

Turkish Journal of Electrical Engineering and Computer Sciences

Measurement of liquid level is an important process variable in the operation of many process industries such as water treatment plants. There are different types of level sensors to measure this parameter, categorized into ultrasonic, capacitive, optical, microwave, magnetostrictive, resistive chain, magnetoresistive, hydrostatic pressure, air bubbler, gamma ray, etc. In this paper, a cylindrical probe capacitive sensor for measuring the level of conductive liquids has been modeled based on a step-by-step mathematical procedure, using MATLAB/Simulink. The steps take the relation between the different capacitances in the model with the height of the conductive liquid into account. The results show a …

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Token-Based Authentication Method For M2m Platforms, Hüseyi̇n Polat, Saadi̇n Oyucu Jan 2017

Token-Based Authentication Method For M2m Platforms, Hüseyi̇n Polat, Saadi̇n Oyucu

Turkish Journal of Electrical Engineering and Computer Sciences

Nowadays the fields in which machine-to-machine (M2M) applications are used and the numbers of M2M devices and users are increasing gradually. In an M2M application, M2M platforms are used in order to follow and analyze the data presented by M2M devices. The communication of multiple users and devices via an M2M platform causes some problems in terms of security. In this study, an M2M platform has been developed by using RestFul web services and NoSQL database. On this platform a token-based authentication method was used for multiple users and devices. In this method, an authorized request approach was adopted for …

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Energy Optimized Scheduling For Non-Preemptive Real-Time Systems, Vasanthamani Kannaian, Visalakshi Palanisamy Jan 2017

Energy Optimized Scheduling For Non-Preemptive Real-Time Systems, Vasanthamani Kannaian, Visalakshi Palanisamy

Turkish Journal of Electrical Engineering and Computer Sciences

Embedded systems have geared up their applications in the field of smart phones, mobile devices, automobiles, and medical instrumentation. Along with the growth of technology, the functional requirements of the systems have also grown multifold. To accommodate these ever increasing functional requirements, the hardware should be designed to include the maximum capability, which in turn increases power consumption. Thus this has to be dynamically managed using software techniques. The dynamic voltage and frequency scaling (DVFS) feature provided in most of the recent processors has enabled power optimization through software. With this feature the processor operating frequency can be reduced on …

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Energy And Area Spectral Efficiency Trade-Off For Mc-Cdma With Carrier Frequency Offset, Junaid Ahmed, Moazzam Islam Tiwana, Omer Ahmed, Sarmad Sohaib Jan 2017

Energy And Area Spectral Efficiency Trade-Off For Mc-Cdma With Carrier Frequency Offset, Junaid Ahmed, Moazzam Islam Tiwana, Omer Ahmed, Sarmad Sohaib

Turkish Journal of Electrical Engineering and Computer Sciences

Intercell interference is a major factor that limits the capacity of cellular wireless communication systems. This paper proposes an accurate statistical model that caters to interference and noise to determine the ergodic capacity. A new expression for ergodic capacity is derived that enables us to calculate area spectral efficiency (ASE) and energy efficiency (EE). This expression has been used to calculate and compare ASE and EE for low and high traffic scenarios with various signal-to-noise ratios and intercell distances.

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A Bidirectional Wireless Power Transfer System For An Electric Vehicle With A Relay Circuit, Chenyang Xia, Wei Wang, Yuling Liu, Kezhang Lin, Yanhe Wang, Xiaojie Wu Jan 2017

A Bidirectional Wireless Power Transfer System For An Electric Vehicle With A Relay Circuit, Chenyang Xia, Wei Wang, Yuling Liu, Kezhang Lin, Yanhe Wang, Xiaojie Wu

Turkish Journal of Electrical Engineering and Computer Sciences

In order to extend the transfer distance, enhance the tolerance for coil misalignment, and improve the capability of energy feedback and power transfer efficiency of conventional wireless power transfer (WPT) systems for electric vehicles, this paper presents a bidirectional WPT topology with a relay circuit. In the proposed topology, the primary and pickup circuits are implemented with virtually identical structures, which can operate in both magnetic field excitation and magnetic field receiving modes to facilitate bidirectional power flow between the primary side and the pickup side. A relay circuit is introduced to achieve high transfer efficiency under special conditions such …

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An Intelligent Pso-Based Energy Efficient Load Balancing Multipath Technique In Wireless Sensor Networks, Sukhchandan Randhawa, Sushma Jain Jan 2017

An Intelligent Pso-Based Energy Efficient Load Balancing Multipath Technique In Wireless Sensor Networks, Sukhchandan Randhawa, Sushma Jain

Turkish Journal of Electrical Engineering and Computer Sciences

To provide a reliable and efficient service, load balancing plays an important role in wireless sensor networks (WSNs). There is a need to maximize the network lifetime for WSNs applications with periodic generation of data. Due to the relationship between energy consumption and network sensor node lifetime, energy consumption in a network should be minimized and balanced in order to increase network lifetime. Energy-efficient load-balancing techniques are needed to solve this problem. In this paper, a particle swarm optimization (PSO)-based energy-efficient load-balancing technique is proposed, in which the required number of routing paths and energy consumption of different nodes and …

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Robust Local Parameter Estimator Based On Least Absolute Value Estimator, Volkan Özdemi̇r, Murat Göl Jan 2017

Robust Local Parameter Estimator Based On Least Absolute Value Estimator, Volkan Özdemi̇r, Murat Göl

Turkish Journal of Electrical Engineering and Computer Sciences

Changes in weather conditions such as temperature and humidity, miscommunication between the control center and circuit breaker transducers and tap changers, and inaccurate manufacturing data may cause parameter errors. Because of incorrect parameters, the state estimator may provide biased state estimates, which may lead to many serious economic and operational results. In order to prevent that, one must identify and correct those parameter errors. This work proposes a local parameter estimator based on the least absolute value (LAV) estimator, which is known to be robust against bad measurements, i.e. measurements with gross error. Considering the increasing number of phasor measurement …

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Constrained Control Allocation For Nonlinear Systems With Actuator Failures Or Faults, Saman Ebrahimi Boukani, Mohammad Javad Khosrowjerdi, Roya Amjadifard Jan 2017

Constrained Control Allocation For Nonlinear Systems With Actuator Failures Or Faults, Saman Ebrahimi Boukani, Mohammad Javad Khosrowjerdi, Roya Amjadifard

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a combination of dynamic constrained control allocation with terminal sliding mode control is proposed for a general class of overactuated nonlinear systems with actuator faults/failures. First, the terminal sliding mode control is designed to converge the system tracking error to zero in a finite-time. Then a control allocation strategy is developed and will be solved by a Lyapunov method, which leads to a dynamic update law with finite-time convergence. This strategy satisfies input limits and when faults/failures occur in some of the actuators, the control signals are automatically redistributed among the healthy actuators. Simulation results on a …

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Minimizing Reverse Current Flow Due To Distributed Generation Via Optimal Network Reconfiguration, Jasrul Jamani Jamian, Muhammad Mohsin Aman, Muhammad Ariff Baharuddin, Ahmad Safawi Mokhtar, Mohd Noor Abdullah Jan 2017

Minimizing Reverse Current Flow Due To Distributed Generation Via Optimal Network Reconfiguration, Jasrul Jamani Jamian, Muhammad Mohsin Aman, Muhammad Ariff Baharuddin, Ahmad Safawi Mokhtar, Mohd Noor Abdullah

Turkish Journal of Electrical Engineering and Computer Sciences

Distributed generation (DG) is widely used to minimize total power losses in distribution networks. However, one of the problems of DG in a grid system is reverse current flow (RCF), which is when the DG output becomes greater than the connected load. Therefore, this paper proposes a multiobjective artificial bee colony (MOABC) algorithm to determine the optimal network reconfiguration for reducing total RCF in DG. The proposed algorithm is tested on 33-bus radial distribution systems in two different scenarios, i.e. base case and with 50% load. The proposed technique can reduce reverse current by up to 93%; however, the total …

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Multiclass Semantic Segmentation Of Faces Using Crfs, Khalil Khan, Nasir Ahmad, Khalil Ullah, Irfanud Din Jan 2017

Multiclass Semantic Segmentation Of Faces Using Crfs, Khalil Khan, Nasir Ahmad, Khalil Ullah, Irfanud Din

Turkish Journal of Electrical Engineering and Computer Sciences

Multiclass semantic image segmentation is widely used in a variety of computer vision tasks, such as object segmentation and complex scene understanding. As it decomposes an image into semantically relevant regions, it can be applied in segmentation of face images. In this paper, an algorithm based on multiclass semantic segmentation of faces is proposed using conditional random fields. In the proposed model, each node corresponds to a superpixel, while the neighboring superpixels are connected to nodes through edges. Unlike previous approaches, which rely on three or four classes, the label set is extended here to six classes, i.e. hair, eyes, …

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Dynamic Security Enhancement Of Power Systems Using Mean-Variance Mapping Optimization, Cavi̇t Fati̇h Küçüktezcan, Veysel Murat İstemi̇han Genç Jan 2017

Dynamic Security Enhancement Of Power Systems Using Mean-Variance Mapping Optimization, Cavi̇t Fati̇h Küçüktezcan, Veysel Murat İstemi̇han Genç

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a preventive control action that involves both generation rescheduling and load curtailment is proposed for enhancing the dynamic security of large interconnected power systems. The control action is formulated as a security-constrained optimization problem that is solved by mean-variance mapping optimization (MVMO) integrated with a self-adaptive penalization technique and artificial neural networks to develop a fast and effective methodology. The proposed methodology is applied to a 16-generator 68-bus test system to solve the security-constrained optimization problem with both continuous and discrete decision variables. To find a proper and cost-effective solution for the control actions within an acceptable …

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A New Segmentation Method Of Cerebral Mri Images Based On The Fuzzy C-Means Algorithm, Mohamed Zaki Abderrezak, Mouatez Billah Chibane, Karim Mansour Jan 2017

A New Segmentation Method Of Cerebral Mri Images Based On The Fuzzy C-Means Algorithm, Mohamed Zaki Abderrezak, Mouatez Billah Chibane, Karim Mansour

Turkish Journal of Electrical Engineering and Computer Sciences

The aim of this work is to present a new method for cerebral MRI image segmentation based on modification of the fuzzy c-means (FCM) algorithm. We used local and nonlocal information distance in the initial function of the robust FCM model. The obtained results of the classification of MRI images showed the effectiveness of the suggested model. Calculation of the similarity index confirms that our method is well adapted to MRI images even in the presence of noise.

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Assessment Of Disordered Voices Based On An Optimized Glottal Source Model, Mounir Boudjerda, Abdellah Kacha Jan 2017

Assessment Of Disordered Voices Based On An Optimized Glottal Source Model, Mounir Boudjerda, Abdellah Kacha

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a method for the assessment of disordered voices is proposed. A feature named mean opening quotient (MOQ) obtained from the glottal source estimation is used as an acoustic cue to summarize the degree of severity of the voice disorder. The analysis method uses the empirical mode decomposition algorithm to estimate the glottal source excitation signal from the speech signal. The logarithm of the magnitude spectrum of the speech signal is decomposed into oscillatory modes, called intrinsic mode functions, that are clustered into two classes, the spectral envelope and the harmonic component. The exploitation of the phase information …

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Distinct Degradation Processes In Zno Varistors: Reliability Analysis And Modeling With Accelerated Ac Tests, Hadi Yadavari, Mustafa Altun Jan 2017

Distinct Degradation Processes In Zno Varistors: Reliability Analysis And Modeling With Accelerated Ac Tests, Hadi Yadavari, Mustafa Altun

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, we investigate different degradation mechanisms of zinc oxide (ZnO) varistors. We propose a model that shows how Vv (defined as DC varistor voltage when a 1-mA DC current is applied) changes with time for different stress levels. For this purpose, accelerated degradation tests are applied for different AC current levels and voltage values are then measured. Different from the common practice in the literature that considers degradation with only decreasing Vv values, we demonstrate either an increasing or a decreasing trend in the Vv parameter. The tests show a decreasing trend in Vv for current levels above …

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A Particle Swarm Optimization And Block-Svd-Based Watermarking For Digital Images, Falgun Thakkar, Vinay Kumar Srivastava Jan 2017

A Particle Swarm Optimization And Block-Svd-Based Watermarking For Digital Images, Falgun Thakkar, Vinay Kumar Srivastava

Turkish Journal of Electrical Engineering and Computer Sciences

The major issues in most watermarking schemes are security, reliability, and robustness against attacks. To achieve these objectives in a watermarking algorithm, the selection of a scale factor to embed the watermark into the host image is a challenging problem. In this paper, a block singular value decomposition (SVD)-based reliable, robust, secure, and fast watermarking scheme is proposed that uses particle swarm optimization (PSO) in the selection of the scale factor. SVD is applied here on the nonoverlapping blocks of LL wavelet subbands. Selected singular values of these blocks are modified with the pixel values of the watermark image. Selected …

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Fpga-Based Soc For Hardware Implementation Of A Local Histogram-Based Video Shot Detector, Abdessalem Ben Abdelali, Mohamed Nidhal Krifa, Abdellatif Mtibaa Jan 2017

Fpga-Based Soc For Hardware Implementation Of A Local Histogram-Based Video Shot Detector, Abdessalem Ben Abdelali, Mohamed Nidhal Krifa, Abdellatif Mtibaa

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we present a video application example and its implementation in a reconfigurable system-on-chip (SOC) platform. The proposed platform employs the benefits of field programmable gate array (FPGA) technology. A prototype based on a Xilinx Virtex-5 FPGA is developed. The application includes a video shot boundary detection module based on the local histogram (LH) technique. Diverse hardware module versions corresponding to different quantization levels and architectural solutions for an LH-based shot detection system are presented. The developed modules have different hardware resource occupations and can be used in a dynamic way to allow flexible management of the target …

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Optimal Fusion Of Multiple Gnss Signals Against Spoofing Sources, Selçuk Şahi̇n, Abedallatif Baba, Tolga Sönmez Jan 2017

Optimal Fusion Of Multiple Gnss Signals Against Spoofing Sources, Selçuk Şahi̇n, Abedallatif Baba, Tolga Sönmez

Turkish Journal of Electrical Engineering and Computer Sciences

Electronic attacks such as spoofing are becoming an increasing threat for satellite-based navigation receivers. The aim of this paper is to develop a preventive method against such electronic attacks. In our scheme, the localization system uses four different Global Navigation Satellite Systems (GNSSs): GPS, Galileo, GLONASS, and Compass. The signals received from these satellite systems will be fused inferentially and will be tracked according to a linear model. The linear model that we developed is solved with a Kalman filter and simulated under different scenarios. When a discrepancy is detected in the output of one of the GNSS receivers due …

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Disk Scheduling With Shortest Cumulative Access Time First Algorithms, Nai̇l Akar, Çağlar Tunç, Mark Gaertner, Fati̇h Erden Jan 2017

Disk Scheduling With Shortest Cumulative Access Time First Algorithms, Nai̇l Akar, Çağlar Tunç, Mark Gaertner, Fati̇h Erden

Turkish Journal of Electrical Engineering and Computer Sciences

A new class of scheduling algorithms is proposed for disk drive scheduling. As opposed to choosing the request with the shortest access time in conventional shortest access time first (SATF) algorithms, we choose an ordered sequence of pending I/O requests at the scheduling instant with the shortest cumulative access time. Additionally, we introduce flexibility for forthcoming requests to alter the chosen sequence. Simulation results are provided to validate the effectiveness of the proposed disk scheduler. Throughput gains of 3% and above are shown to be attainable, although this occurs at the expense of increased computational complexity.

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Timeline - Space Race, Jesse Lackey Jan 2017

Timeline - Space Race, Jesse Lackey

Cold War & Space Race

The infographic attached along with this note is a timeline of several historical events that took place primarily in the 20th century. This timeline will serve as a useful piece in the classroom when one is teaching the reading, Hidden Figures, and looking to pinpoint it and the events related to it within a historical context. The timeline chronologically compares groundbreaking historical events such as the Civil Rights Act of 1964 and the creation of NASA alongside the historical presence of the three women, Dorothy Vaughan, Katherine Johnson, and Mary Jackson, that the reading is focused around.

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Uses For Graphene, Marcus R. Schmidt Jan 2017

Uses For Graphene, Marcus R. Schmidt

Natural Sciences Student Research Presentations

This slide presentation for the Natural Sciences Poster Session at Parkland College discusses graphene, which is a chemically or mechanically produced single layer of pure carbon atoms. The thinnest compound known to man is also one of the strongest, with uses in technology and the health industry from faster charging batteries to motorcycle helmets. The remaining slides summarize a process by which free radicals are reduced in graphene by being treated with butyl acrylate polymerization.

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In-Vehicle Evaluation Of Milled Rumble Strips At Pre- And Post-Chip Sealed Maintenance Periods, Ernest Tufuor, Laurence Rilett, Christopher Lefrois Jan 2017

In-Vehicle Evaluation Of Milled Rumble Strips At Pre- And Post-Chip Sealed Maintenance Periods, Ernest Tufuor, Laurence Rilett, Christopher Lefrois

Nebraska Department of Transportation: Research Reports

Driver fatigue and drowsiness can have a profound impact on safety. Centerline and shoulder rumble strips (RS) are popular countermeasures designed to produce audible and tactile warning when vehicles deviate from the travel lane onto the RS. This reduces the risk of lane departure crashes. Studies show that the noise produced by RS is a function of many variables. RS depth is known to have the greatest impact on alerting drivers. However, chip-seal pavement maintenance operations have the tendency to reduce the original RS design depth, which may have an impact on the functional effectiveness of the RS. The purpose …

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Nebraska Public Water Supply Program Summary Report 2017 Jan 2017

Nebraska Public Water Supply Program Summary Report 2017

Nebraska Department of Environmental Quality: Reports

The United States Environmental Protection Agency (EPA) established the Public Water System Supervision (PWSS) Program under the authority of the 1974 Safe Drinking Water Act (SDWA). Under the SDWA and the 1986 Amendments, EPA sets national limits on contaminant levels in drinking water to ensure that the water is safe for human consumption. These limits are known as Maximum Contaminant Levels (MCLs) and Maximum Residual Disinfectant Levels (MRDLs). For some regulations, EPA establishes treatment techniques in lieu of an MCL to control unacceptable levels of contaminants in water.

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2017 Nebraska Groundwater Quality Monitoring Report Jan 2017

2017 Nebraska Groundwater Quality Monitoring Report

Nebraska Department of Environmental Quality: Reports

The 2001 Nebraska Legislature passed LB329 (Neb. Rev. Stat. §46-1304) which, in part, directed the Nebraska Department of Environmental Quality (NDEQ) to report on groundwater quality monitoring in Nebraska. Reports have been issued annually since December 2001. The text of the statute applicable to this report follows: “The Department of Environmental Quality shall prepare a report outlining the extent of ground water quality monitoring conducted by natural resources districts during the preceding calendar year. The department shall analyze the data collected for the purpose of determining whether or not ground water quality is degrading or improving and shall present the …

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Compensatory Response Of Fathead Minnow Larvae Following A Pulsed In-Situ Exposure To A Seasonal Agricultural Runoff Event, Jonathan M. Ali, John Sangster, Daniel D. Snow, Shannon L. Bartelt-Hunt, Alan S. Kolok Jan 2017

Compensatory Response Of Fathead Minnow Larvae Following A Pulsed In-Situ Exposure To A Seasonal Agricultural Runoff Event, Jonathan M. Ali, John Sangster, Daniel D. Snow, Shannon L. Bartelt-Hunt, Alan S. Kolok

Nebraska Water Center: Faculty Publications

Agriculturally-dominated waterways such as those found throughout the Midwestern United States often experience seasonal pulses of agrichemical contaminants which pose a potential hazard to aquatic organisms at varying life stages. The objective of this study was to characterize the developmental plasticity of fathead minnow larvae in a natural environment subject to a seasonal episodic perturbation in the form of a complex mixture of agricultural stressors. Fathead minnow larvae were maintained at the Elkhorn River Research Station for a 28-d in situ exposure to an agrichemical pulse event.Minnow larvae were sampled after 14 and 28 days to characterize developmental plasticity through …

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Development Of Innovative High-Energy Neutron And Gamma-Ray Shielding Material Based On High Density Cement And Crumb Rubber, Pawitra Aim-O Jan 2017

Development Of Innovative High-Energy Neutron And Gamma-Ray Shielding Material Based On High Density Cement And Crumb Rubber, Pawitra Aim-O

Chulalongkorn University Theses and Dissertations (Chula ETD)

The incorporation of carbon and hydrogen-rich material into radiation shielding material can improve its shielding performance. High-density cement mixed with crumb rubber was studied to be a gamma ray and neutron shielding material. Shielding materials were designed using high-density cement mixed with 5 - 25 vol% of crumb rubber. Monte Carlo N-Particle code was employed to simulate radiation shielding performances of the composed materials. The utilized neutron and photon sources were Am-241/Be and Co-60, respectively. These shielding designs were fabricated and experimentally evaluated on the radiation shielding properties. The cracking mechanism of high-density cement mixed with lead (HDCRL) was also …

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Evaluation Of Captured Co2 And Waste H2 As Potential Feedstock For Methanol Production, Kankanit Kitsahawong Jan 2017

Evaluation Of Captured Co2 And Waste H2 As Potential Feedstock For Methanol Production, Kankanit Kitsahawong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Global warming is the critical issue that is the result of Greenhouse Gases (GHGs) emission. Carbon dioxide (CO2) is concerned to be major GHGs. Thus, Carbon dioxide utilization is the promising pathway to reduce the emission of CO2. To utilize CO2, waste hydrogen from sodium methoxide production is used to produce methanol which can be recycled as reactant of sodium methoxide synthesis. Carbon dioxide hydrogenation process is used for produce methanol from CO2 and waste H2 from various size of sodium methoxide production process. In every size of methanol production process, methanol which produce from the process is 16.3% of …

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Conceptual Design Process Improvement For Drainage Systemusing Project Management, Wantanee Kongpanya Jan 2017

Conceptual Design Process Improvement For Drainage Systemusing Project Management, Wantanee Kongpanya

Chulalongkorn University Theses and Dissertations (Chula ETD)

The major concern in the architecture, engineering, and construction (AEC) industry is time, cost, and quality. The design for industrial building project usually complex, particularly in a field of mechanical and piping process due to the large involvement of project stakeholders. The case company, which is the specialist supplier of industrial piping solution in Thailand, reported the issue of redesigns regarding to their poor project management of conceptual design process in construction project that effect to their work performance and customer satisfaction. Thus, the purpose of this study was to improve the process of conceptual design using project management concept …

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Effect Of Operating Conditions And Ion Contaminations On Electro Coagulation And Oxidation Processes For Water Quality Improvement, Vouchlay Theng Jan 2017

Effect Of Operating Conditions And Ion Contaminations On Electro Coagulation And Oxidation Processes For Water Quality Improvement, Vouchlay Theng

Chulalongkorn University Theses and Dissertations (Chula ETD)

The objective of this study is to investigate the effect of ion contaminations and operating conditions on Electro Coagulation (EC) and Oxidation (EO) in turbidity and natural organic matter (NOM) removal. The experiments were conducted in 4 liters column. Ferrous and calcium were chosen as contaminated ions. The operating condition was varied in terms of initial pH and current density. 100 NTU turbidity and 70 mg/L NOM were synthesized from bentonite and humic acid (HA), respectively. The results showed that bipolar arrangement of electrodes with 2 cm gap was the optimal condition in terms of gas flow rate and electrode …

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