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Articles 41191 - 41220 of 196033

Full-Text Articles in Engineering

Sources Of Variability And Uncertainty In Food-Energy-Water Nexus Systems, Heydi Calderon-Ambelis, Deepak R. Keshwani Jan 2022

Sources Of Variability And Uncertainty In Food-Energy-Water Nexus Systems, Heydi Calderon-Ambelis, Deepak R. Keshwani

Department of Agricultural and Biological Systems Engineering: Faculty Publications

A nexus approach contributes to the strategic allocation of resources to secure food, energy, and water for the world population. Integrated models considering the complex interactions across food, energy, and water (FEW) enhance decision-making and strategic planning towards resilience. However, a significant number of the existing integrated models leave unaddressed the inherent variability and uncertainty present in the FEW sectors. Here, we review the importance of characterizing variability over spatial and temporal scales and the importance of decreasing the uncertainty present within a FEW nexus systems. The review also discusses existing modeling tools that address variability and uncertainty on single …


Modeling Water Quantity And Quality Nonlinearities For Watershed Adaptability To Hydroclimate Extremes In Agricultural Landscapes, Juan Carlos Jaimes-Correa, Francisco Muñoz-Arriola, Shannon Bartelt-Hunt Jan 2022

Modeling Water Quantity And Quality Nonlinearities For Watershed Adaptability To Hydroclimate Extremes In Agricultural Landscapes, Juan Carlos Jaimes-Correa, Francisco Muñoz-Arriola, Shannon Bartelt-Hunt

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Changing water supplies and demands, inherent to climate fluctuations and human activities, are pushing for a paradigm shift in water management worldwide. The occurrence of extreme hydrometeorological and climate events such as extended wet periods and droughts, compounded with contaminants, impair the access to water resources, demanding novel designs, construction, and management across multiple hydrologic scales and biogeochemical processes. A constraint to studying hydrologic and biogeochemical disturbances and improving best management practices for water quantity and quality at the watershed scale resides in the suitable monitoring, data availability, and the creation of frameworks. We hypothesize that streamflow and contaminants, simulated …


Comparison Effect On Biogas Production From Vegetable And Fruit Waste With Rumen Digesta Through Co-Digestion Process, Anika Tasnim, Muhammad Rashed Al Mamun, Md Anwar Hossen, Md Towfiqur Rahman, Md Janibul Alam Soeb Jan 2022

Comparison Effect On Biogas Production From Vegetable And Fruit Waste With Rumen Digesta Through Co-Digestion Process, Anika Tasnim, Muhammad Rashed Al Mamun, Md Anwar Hossen, Md Towfiqur Rahman, Md Janibul Alam Soeb

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Biogas is the best renewable energy as it can be produced from any biomass for example any plant or living organism. The purpose of this research was to produce biomethane from co-digestion of vegetable and fruit waste with rumen digesta through anaerobic digestion process. In this research, two trials of experiment were conducted. Each trial has three different sample with different mixing ratios. Raw materials used in the experiment was rumen digesta of goat and cow, potato, capsicum, cucumbers, onions, radish, cauliflower, carrot, leafy vegetables, apple, banana, and papaya. In each sample, 1200 gram of raw materials were used. Hydraulic …


Influences Of Artificial Light On Mating Of Black Soldier Fly (Hermetia Illucens): A Review, Md Rabiul Awal, Md Masudur Rahman, Md Abdur Razzak Choudhury, Md Mehedi Hasan, Md Towfiqur Rahman, Md Fuad Mondal Jan 2022

Influences Of Artificial Light On Mating Of Black Soldier Fly (Hermetia Illucens): A Review, Md Rabiul Awal, Md Masudur Rahman, Md Abdur Razzak Choudhury, Md Mehedi Hasan, Md Towfiqur Rahman, Md Fuad Mondal

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Black soldier fly (Hermetia illucens) is a potential insect species which can convert biodegradable materials and some indigestible organic waste into valuable biomass. Because of having good quality of fat and protein, its production and use in animal feed are being extended day by day. To fulfill the future demand re-searchers are trying to find out the successful mass rearing techniques of H. illucens in laboratory or indoor condition. However, the most critical part of H. illucens mass production is obtaining successful mating. This insect is very sensitive to light. It prefers direct sunlight for its …


Geospatial Distribution Of Age-Adjusted Incidence Of The Three Major Types Of Pediatric Cancers And Waterborne Agrichemicals In Nebraska, Balkissa S. Ouattara, Jagadeesh Puvvula, Azar Abadi, Siddhi Munde, Alan S. Kolok, Shannon Bartelt-Hunt, Jesse E. Bell, Christopher S. Wichman, Eleanor Rogan Jan 2022

Geospatial Distribution Of Age-Adjusted Incidence Of The Three Major Types Of Pediatric Cancers And Waterborne Agrichemicals In Nebraska, Balkissa S. Ouattara, Jagadeesh Puvvula, Azar Abadi, Siddhi Munde, Alan S. Kolok, Shannon Bartelt-Hunt, Jesse E. Bell, Christopher S. Wichman, Eleanor Rogan

Department of Civil and Environmental Engineering: Faculty Publications

This study was conducted to examine, at the county level, the relationship between pediatric cancer incidence rate and atrazine and nitrate mean concentrations in surface and groundwater. A negative binomial regression analysis was performed to investigate the association between central nervous system (CNS) tumors, leukemia, lymphoma, and atrazine and nitrate mean concentrations in groundwater. The age-adjusted brain and other CNS cancer incidence was higher than the national average in 63% of the Nebraska counties. After controlling for the counties socio-economic status and nitrate concentrations in groundwater, counties with groundwater atrazine concentrations above 0.0002 μg/L had a higher incidence rate for …


Probability-Based Crack Width Estimation Model For Flexural Members Of Underground Rc Box Culverts, Sang-Hyo Kim, Syed Haider Ali Shah, Sang-Kyun Woo, Inyeop Chu, Chungwook Sim Jan 2022

Probability-Based Crack Width Estimation Model For Flexural Members Of Underground Rc Box Culverts, Sang-Hyo Kim, Syed Haider Ali Shah, Sang-Kyun Woo, Inyeop Chu, Chungwook Sim

Department of Civil and Environmental Engineering: Faculty Publications

Crack control for slabs and beams in current design practices in Korea are based on the Frosch’s model, which is adapted in ACI 318. It is more difficult to have consistent quality control in underground construction sites, such as the RC box culverts used for electric power distribution built below the ground level. There are more discrepancies between the as-built dimensions and the design dimensions provided in drawings in these structures. Due to this variability in construction error, the crack widths measured in such structures have higher potential to have more differences than the calculated values. Although crack control is …


Recent Advances In Biosensors For Detection Of Covid-19 And Other Viruses, Shobhit K. Patel, Jaymit Surve, Juveriya Parmar, Kawsar Ahmed, Francis M. Bui, Fahad Ahmed Al-Zahrani Jan 2022

Recent Advances In Biosensors For Detection Of Covid-19 And Other Viruses, Shobhit K. Patel, Jaymit Surve, Juveriya Parmar, Kawsar Ahmed, Francis M. Bui, Fahad Ahmed Al-Zahrani

Department of Mechanical and Materials Engineering: Faculty Publications

This century has introduced very deadly, dangerous, and infectious diseases to humankind such as the influenza virus, Ebola virus, Zika virus, and the most infectious SARS-CoV-2 commonly known as COVID-19 and have caused epidemics and pandemics across the globe. For some of these diseases, proper medications, and vaccinations are missing and the early detection of these viruses will be critical to saving the patients. And even the vaccines are available for COVID-19, the new variants of COVID-19 such as Delta, and Omicron are spreading at large. The available virus detection techniques take a long time, are costly, and complex and …


A Robot-Assisted Acoustofluidic End Effector, Jan Durrer, Prajwal Agrawal, Ali Ozgul, Stephen C.F. Neuhauss, Nitesh Nama, Daniel Ahmed Jan 2022

A Robot-Assisted Acoustofluidic End Effector, Jan Durrer, Prajwal Agrawal, Ali Ozgul, Stephen C.F. Neuhauss, Nitesh Nama, Daniel Ahmed

Department of Mechanical and Materials Engineering: Faculty Publications

Liquid manipulation is the foundation of most laboratory processes. For macroscale liquid handling, both do-it-yourself and commercial robotic systems are available; however, for microscale, reagents are expensive and sample preparation is difficult. Over the last decade, lab-on-a-chip (LOC) systems have come to serve for microscale liquid manipulation; however, lacking automation andmulti-functionality. Despite their potential synergies, each has grown separately and no suitable interface yet exists to link macro-level robotics with micro-level LOC or microfluidic devices. Here, we present a robot-assisted acoustofluidic end effector (RAEE) system, comprising a robotic arm and an acoustofluidic end effector, that combines robotics and microfluidic functionalities.We …


Causes Influencing Construction Waste Generation During The Design Process: An Analytical Study, Aya Saad, Ayman Ahmed Ezzat Othman Jan 2022

Causes Influencing Construction Waste Generation During The Design Process: An Analytical Study, Aya Saad, Ayman Ahmed Ezzat Othman

Architectural Engineering

Despite the social and economic contributions of the construction industry towards achieving sustainable development objectives, it has an adverse effect on the environment such as the generation of waste, water, and energy consumption. Construction waste (CW) is the loss of materials that are produced during or after the construction process and has no remaining value. Several countries promote waste elimination plans at early stages to reduce CW at its source. The Egyptian government is expanding its investments in new mega projects and infrastructure facilities like new administrative capital, bridges, roads, energy projects which resulted in increasing the rate and amount …


Achieving Sustainability Through Reducing Risks During Architecture Design Process: A Lean Management Perspective, Sherouk Abdelrehim, Ayman Ahmed Ezzat Othman Jan 2022

Achieving Sustainability Through Reducing Risks During Architecture Design Process: A Lean Management Perspective, Sherouk Abdelrehim, Ayman Ahmed Ezzat Othman

Architectural Engineering

The construction industry, as one of the largest industries in the world, plays a critical role in achieving national and international social and economic sustainable development goals. Socially, it is concerned with delivering long-term projects that turn client and end-user requirements into designs that specify technical aspects, functional specific requirements, and standards of quality. Economically, the construction industry contributes to a country's gross domestic product (GDP) by creating jobs and providing the country's infrastructure. the construction industry's nature is more vulnerable than other industries. This is believed to be due to the complex and dynamic nature of construction projects, as …


Overcoming The Limitations Of The Green Pyramid Rating System In The Egyptian Construction Industry: A Critical Analysis, Ahmed Osama Daoud, Ayman Ahmed Ezzat Othman, Obas John Ebohon, Ali Bayyati Jan 2022

Overcoming The Limitations Of The Green Pyramid Rating System In The Egyptian Construction Industry: A Critical Analysis, Ahmed Osama Daoud, Ayman Ahmed Ezzat Othman, Obas John Ebohon, Ali Bayyati

Architectural Engineering

Despite the tangible contributions of the construction industry to social development and economic growth, it is known for its natural resources overconsumption and solid waste (SW) generation both of which have major negative impacts on the natural environment. In the particular case of materials waste, the construction industry worldwide accounts for about 50% of global annual generated SW. In addition, construction materials may contribute up to 50% of the total project cost. Accordingly, the negative implications of the construction industry have compelled many nations to develop green building rating systems in order to preserve the environment, promote the economic efficiency …


Causes And Impacts Of Site Accidents In The Egyptian Construction Industry, Mostafa Adel, Omar Elnawawy, Ayman Ahmed Ezzat Othman, Mohamed Badawy Jan 2022

Causes And Impacts Of Site Accidents In The Egyptian Construction Industry, Mostafa Adel, Omar Elnawawy, Ayman Ahmed Ezzat Othman, Mohamed Badawy

Architectural Engineering

This paper aims to investigate the causes and impacts of site accidents in the Egyptian construction industry. To achieve this aim, a research methodology consisted of literature review and survey questionnaire was developed to accomplish three objectives. First, literature review was used to investigate the nature of the construction industry, identify and classify the causes of site accidents as well as their social and economic impacts on organizations and affected families. Second, a survey questionnaire was conducted with a representative sample of large and medium sized construction firms in Egypt to examine their perception of the causes of site accidents. …


Investigation Of Domestic Level Ev Chargers In The Distribution Network: An Assessment And Mitigation Solution, Arsalan Hussain Zaidi Jan 2022

Investigation Of Domestic Level Ev Chargers In The Distribution Network: An Assessment And Mitigation Solution, Arsalan Hussain Zaidi

Doctoral

This research focuses on the electrification of the transport sector. Such electrification could potentially pose challenges to the distribution system operator (DSO) in terms of reliability, power quality and cost-effective implementation. This thesis contributes to both, an Electrical Vehicle (EV) load demand profiling and advanced use of reactive power compensation (D-STATCOM) to facilitate flexible and secure network operation. The main aim of this research is to investigate the planning and operation of low voltage distribution networks (LVDN) with increasing electrical vehicles (EVs) proliferation and the effects of higher demand charging systems. This work is based on two different independent strands …


The Third International Hackathon For Applying Insights Into Large-Scale Genomic Composition To Use Cases In A Wide Range Of Organisms, Kimberly Walker, Divya Kalra, Rebecca Lowdon, Guangyi Chen, Fritz J. Sedlazeck, Ben Busby, Chia-Sin Liew, Et Al. Jan 2022

The Third International Hackathon For Applying Insights Into Large-Scale Genomic Composition To Use Cases In A Wide Range Of Organisms, Kimberly Walker, Divya Kalra, Rebecca Lowdon, Guangyi Chen, Fritz J. Sedlazeck, Ben Busby, Chia-Sin Liew, Et Al.

Nebraska Center for Biotechnology: Faculty and Staff Publications

In October 2021, 59 scientists from 14 countries and 13 U.S. states collaborated virtually in the Third Annual Baylor College of Medicine & DNANexus Structural Variation hackathon. The goal of the hackathon was to advance research on structural variants (SVs) by prototyping and iterating on open-source software. This led to nine hackathon projects focused on diverse genomics research interests, including various SV discovery and genotyping methods, SV sequence reconstruction, and clinically relevant structural variation, including SARS-CoV-2 variants. Repositories for the projects that participated in the hackathon are available at https://github.com/collaborativebioinformatics.


Estimating Beam Strength Of Metallic Gear Materials, Edward E. Osakue, Lucky Anetor Jan 2022

Estimating Beam Strength Of Metallic Gear Materials, Edward E. Osakue, Lucky Anetor

Faculty Publications

Expressions for the pulsating or beam strengths of many popular metallic gear materials are derived based on the tensile strength and endurance ratio. The strength values predicted are for a reliability of 99% at load cycles corresponding to that of the endurance strength of the materials. The expressions are based on the consideration of the revised Lewis gear root stress formula by treating the design parameters as random variables associated with the lognormal probability density function and application of the Gerber fatigue failure rule. Pulsating strength predictions are compared with those of AGMA estimates for through-hardened steels and other materials. …


A Contact Stress Capacity Model For Cylindrical Wormsets, Edward E. Osakue, Lucky Anetor Jan 2022

A Contact Stress Capacity Model For Cylindrical Wormsets, Edward E. Osakue, Lucky Anetor

Faculty Publications

A contact stress capacity expression is derived for cylindrical worm sets by considering the worm as a helical rack mating with a helical gear. The concept of the equivalent spur gear for a helical gear defined by the instantaneous radius of curvature in the virtual plane of the helical gear is utilized in the contact stress capacity model formulation. All the basic design parameters of worm and gear are incorporated in the expression which explicitly shows the influence of the base and nominal helix angles on the contact stress. By considering the geometry of the worm and gear in engagement, …


Overview Of Standards For Technological And Engineering Literacy (Other), Philip Reed, Tyler Love, Scott Bartholomew, Kelly Dooley Jan 2022

Overview Of Standards For Technological And Engineering Literacy (Other), Philip Reed, Tyler Love, Scott Bartholomew, Kelly Dooley

STEMPS Faculty Publications

In 2020, the International Technology and Engineering Educators Association (ITEEA) published Standards for Technological and Engineering Literacy: The Role of Technology and Engineering in STEM Education (STEL) [1]. These standards open with a clear rationale why all Pk-12 students should study technology and engineering:

Technology and engineering are pervasive in all aspects of our lives. Every human activity is dependent upon the products, systems, and processes created to help grow food, provide shelter, communicate, work, and recreate. As the world grows more complex, it is increasingly important for everyone to understand more about technology and engineering [1, p. 1].

The …


Blast-Building Leaders For Advancing Science And Technology: A Partnership Between The Virginia Space Grant Consortium And The University Of Virginia, Virginia Polytechnic Institute, And Old Dominion University, Cynthia Tomovic, Mary Sandy, Julie Back, Vukica Jovanovic, Kim Lester, Edward Murphy, Sueanne Mckinney, Mileta Tomovic Jan 2022

Blast-Building Leaders For Advancing Science And Technology: A Partnership Between The Virginia Space Grant Consortium And The University Of Virginia, Virginia Polytechnic Institute, And Old Dominion University, Cynthia Tomovic, Mary Sandy, Julie Back, Vukica Jovanovic, Kim Lester, Edward Murphy, Sueanne Mckinney, Mileta Tomovic

STEMPS Faculty Publications

This paper presents the development and delivery of educational summer intensive programs for high school students that are designed to encourage students’ interests in the STEM-related fields and the motivation to pursue a STEM-related degrees in college. BLAST (Building Leaders to Advance Science and Technology) is designed as a summer-intensive, residential, on-campus STEM-learning experience for rising ninth and tenth graders. With the intention of improving the STEM-related workforce pipeline in the Commonwealth of Virginia, Virginia Space Grant Consortium (VSGC) offers multiple BLAST programs across the Commonwealth. BLAST programs are designed as intensive three-day, STEM-related three-hour lecture-lab experiences that are reinforced …


Comparison Of Stationary And Mobile Canopy Sensing Systems For Irrigation Management Of Maize And Soybean In Nebraska, Sandeep Bhatti, Derek M. Heeren, Susan A. O’Shaughnessy, Steven R. Evett, Mitchell S Maguire, Suresh Pradhyun Kashyap, Christopher M. U. Neale Jan 2022

Comparison Of Stationary And Mobile Canopy Sensing Systems For Irrigation Management Of Maize And Soybean In Nebraska, Sandeep Bhatti, Derek M. Heeren, Susan A. O’Shaughnessy, Steven R. Evett, Mitchell S Maguire, Suresh Pradhyun Kashyap, Christopher M. U. Neale

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Accurate knowledge of plant and field characteristics is crucial for irrigation management. Irrigation can potentially be better managed by utilizing data collected from various sensors installed on different platforms. The accuracy and repeatability of each data source are important considerations when selecting a sensing system suitable for irrigation management. The objective of this study was to compare data from multispectral (red and near-infrared bands) and thermal (long wave thermal infrared band) sensors mounted on different platforms to investigate their comparative usability and accuracy. The different sensor platforms included stationary posts fixed on the ground, the lateral of a center pivot …


Inspiring Young Students To Pursue Engineering, Tami M. Brown-Brandl, Brian Steward Jan 2022

Inspiring Young Students To Pursue Engineering, Tami M. Brown-Brandl, Brian Steward

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Imagine elementary school students understanding inputs and outputs, choosing appropriate sensors, and programming an autonomous robot. Imagine middle school students learning about PID control and creating advanced programs for sensor-based decision making. Imagine high school students using CAD to design drive trains, manufacturing parts with CNC machine tools, using finite element analysis to adjust the design, ordering custom components from a machine shop, using image processing for target recognition, and applying path planning and motion control. We have witnessed all of these skills. They happened outside of traditional classrooms, and they were all student-driven.

Yes, it’s true, and it’s amazing. …


Proposed New Framework Scheme For Path Loss In Wireless Bodyarea Network, Israa Al_Barazanchi, Yitong Niu, Haider Rasheed Abdulshaheed, Wahidah Hashim, Ammar Ahmed Alkahtani, Elika Daghighi, Zahraa A. Jaaz, Shihab A. Shawkat Jan 2022

Proposed New Framework Scheme For Path Loss In Wireless Bodyarea Network, Israa Al_Barazanchi, Yitong Niu, Haider Rasheed Abdulshaheed, Wahidah Hashim, Ammar Ahmed Alkahtani, Elika Daghighi, Zahraa A. Jaaz, Shihab A. Shawkat

Iraqi Journal for Computer Science and Mathematics

Recent technical developments in wi-fi networking, microelectronic integration and programming,sensors and the Internet have enabled us to create and enforce a range of new framework schemes to fulfil thenecessities of healthcare-related wireless body area network (WBAN). WBAN sensors continually screen andmeasure patients’ indispensable signs and symptoms, and relay them to scientific monitoring for diagnosis. WBANhas a range of applications, the most necessary of which is to help patients suffering diseases to stay alive. The qualityinstance is the coronary heart implant sensor, whose video display unit monitors coronary heart sign and continuouslytransmits it. This setup eliminates the need for patients to …


Blockchain-Technology-Based Solutions For Iot Security, Israa Al-Barazanchi, Aparna Murthy, Ahmad Abdul Qadir Al Rababah, Ghadeer Khader, Haider Rasheed Abdulshaheed, Elika Daghighi, Yitong Niu Jan 2022

Blockchain-Technology-Based Solutions For Iot Security, Israa Al-Barazanchi, Aparna Murthy, Ahmad Abdul Qadir Al Rababah, Ghadeer Khader, Haider Rasheed Abdulshaheed, Elika Daghighi, Yitong Niu

Iraqi Journal for Computer Science and Mathematics

After a long period of development, blockchain innovation has received much attention from scholarsand industry practitioners alike. This innovation allows the issuance of smart contracts, which are utilised to automateand execute deals amongst clients. Blockchain is also being used nowadays by a few IT applications as a specialisedfoundation. This technology also prevents the duplication of information similar to what is being done with Bitcoinand other cryptocurrencies. Specifically, Bitcoin records are virtually impossible to alter as this cryptocurrency isbeing traded amongst hundreds of thousands of servers. Therefore, to launch a successful attack, the aggressor shouldchange the Bitcoin records of 51% of …


Vertex And Region Colourings Of Planar Idempotent Divisor Graphsof Commutative Rings., Mohammed N. Authman, Husam Q. Mohammad, Nazar H. Shuker Jan 2022

Vertex And Region Colourings Of Planar Idempotent Divisor Graphsof Commutative Rings., Mohammed N. Authman, Husam Q. Mohammad, Nazar H. Shuker

Iraqi Journal for Computer Science and Mathematics

The idempotent divisor graph of a commutative ring R is a graph with vertices set in R * = R-{0}, andany distinct vertices x and y are adjacent if and only if x.y = e. For some non-unit idempotent elemente2=e∈R, it isdenoted byΠ(R) . The purpose of this work is to use some properties of ring theory and graph theory to determine theclique number, the chromatic number and the region chromatic number for each planar idempotent divisor graph ofthe commutative rings. furthermore, we show that the clique number is equal to the chromatic number for any planaridempotent divisor graph. Results …


Fuzzy Soc-T-Abso Sub-Modules, Saad S. Marie, Hatam Y. Khalaf Jan 2022

Fuzzy Soc-T-Abso Sub-Modules, Saad S. Marie, Hatam Y. Khalaf

Iraqi Journal for Computer Science and Mathematics

This research analyses the correlation that exists between fuzzy T-ABSO and fuzzy socle. To answerthis question, we define a new concept called, fuzzy socle T-ABSO submodules. Results showed many propertiesthat satisfied the new notion. In addition, we applied some algebra operations and found the relationship betweenfuzzy T-ABSO and fuzzy socle -T-ABSO. We also investigated the structure of fuzzy socle T-ABSO sub- modules ofa module under fuzzy direct sum, homomorphic image and intersection. Moreover, the relation between fuzzy socleT-ABSO sub-module and other types of fuzzy sub-module was presented. The implications of this study could beused to define new concepts that depend …


Effect Of Reduction Methods On The Properties Of Composite Films Of Bacterial Cellulose-Silver Nanoparticles, Ratchanon Jenkhongkarn Jan 2022

Effect Of Reduction Methods On The Properties Of Composite Films Of Bacterial Cellulose-Silver Nanoparticles, Ratchanon Jenkhongkarn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Composite films of bacterial cellulose-silver nanoparticles (BC-Ag) were prepared by different methods of in-situ reduction of silver, using sodium hydroxide, ascorbic acid, chitosan, and UV irradiation. The effects of the reduction methods on their properties were investigated. The chitosan-reduced composite exhibited dispersed silver nanoparticles (AgNPs) within the nanocellulose matrix with the smallest size, while the ascorbic-reduced composite displayed the largest size. The incorporation of AgNPs tended to reduce the crystallinity of the composites, except for the ascorbic-reduced composite which exhibited an increase in crystallinity. Mechanical testing revealed that the ascorbic-reduced composite had the highest Young's modulus of 8960 MPa, whereas …


การวิเคราะห์ฉากทัศน์สำหรับศักยภาพชีวมวลของการผลิตไฟฟ้าจากวัสดุเหลือทิ้งทางการเกษตรในประเทศไทย, ธัญชนก เชิดชู Jan 2022

การวิเคราะห์ฉากทัศน์สำหรับศักยภาพชีวมวลของการผลิตไฟฟ้าจากวัสดุเหลือทิ้งทางการเกษตรในประเทศไทย, ธัญชนก เชิดชู

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้มีวัตถุประสงค์เพื่อวิเคราะห์ฉากทัศน์ศักยภาพชีวมวลของการผลิตไฟฟ้าจากวัสดุเหลือทิ้งทางการเกษตรในประเทศไทย ภายใต้การวิเคราะห์ปัจจัยที่ทำให้เกิดผลกระทบและปัจจัยที่มีแนวโน้มที่จะมีการเปลี่ยนแปลง โดยการวิเคราะห์ได้ใช้เครื่องมือในการประเมินปัจจัยภายนอกต่างๆ ด้วยการวิเคราะห์ STEEP Analysis และทำการจัดลำดับปัจจัยเพื่อพิจารณาเลือกสถานการณ์ ที่ถูกกำหนดด้วยปัจจัยที่ทำให้เกิดผลกระทบและปัจจัยที่มีแนวโน้มที่จะมีการเปลี่ยนแปลงมากที่สุด พบว่าปัจจัยสำคัญที่ทำให้เกิดผลกระทบ (Impact) และมีแนวโน้มที่จะเกิดการเปลี่ยนแปลง (Uncertainty) ต่อฉากทัศนศักยภาพชีวมวลของการผลิตไฟฟ้าจากวัสดุเหลือทิ้งทางการเกษตรในประเทศไทย ได้แก่ ปัจจัยด้านการสนับสนุนนโยบายจากภาครัฐ เช่น อัตรารับซื้อไฟฟ้าจากชีวมวลในรูปแบบ Feed-in Tariff และปัจจัยด้านต้นทุนการผลิตไฟฟ้า เช่น ต้นทุนค่าเชื้อเพลิงชีวมวล ต้นทุนค่าการสร้างและค่าใช้จ่ายในการดำเนินการ ทั้งนี้ ได้กำหนดตัวชี้วัดสำหรับการติดตามและตรวจสอบสถานการณ์ ซึ่งเป็นปัจจัยเชิงปริมาณ ได้แก่ การวิเคราะห์ศักยภาพชีวมวลของการผลิตไฟฟ้าจากวัสดุเหลือทิ้งทางการเกษตร และการวิเคราะห์ต้นทุนส่วนเพิ่มในการลดก๊าซเรือนกระจก (Marginal Abatement Cost : MAC) เพื่อสะท้อนให้เห็นถึงการวิเคราะห์ศักยภาพเชิงปริมาณในแต่ละสถานการณ์ภายใต้เงื่อนไขของปัจจัยขับคลื่อน โดยได้แบ่งออกเป็น 3 สถานการณ์ ซึ่งพบว่า ศักยภาพชีวมวลของการผลิตไฟฟ้าจากวัสดุเหลือทิ้งทางการเกษตร มากที่สุด 38,376 เมกะวัตต์ รองลงมา ได้แก่ 24,940 เมกะวัตต์ และ 10,596 เมกะวัตต์ ตามลำดับ ในส่วนของการวิเคราะห์ต้นทุนส่วนเพิ่มในการลดก๊าซเรือนกระจก อยู่ระหว่าง -980 ถึง 131 บาท/ตันคาร์บอนไดออกไซด์เทียบเท่า


Optimal Operation Schedule Of Battery Energy Storage System For Supporting Variable Renewable Energy In Generation System, Chalermjit Klansupar Jan 2022

Optimal Operation Schedule Of Battery Energy Storage System For Supporting Variable Renewable Energy In Generation System, Chalermjit Klansupar

Chulalongkorn University Theses and Dissertations (Chula ETD)

Variable renewable energy (VRE) generation alters residual demand curves, leading to high operating costs for conventional generators. Additionally, the variable nature of VRE causes a mismatch between electricity demand and generation, resulting in greater expected energy not supplied (EENS) values, which represent a critical component of power generation costs. To alleviate the impact of VRE, utility-scale battery energy storage systems (BESSs) provide ancillary services. The BESSs’ general applications are spinning reserve, regulation, and ramping. This paper proposes a method to determine daily operation schedules for grid-scale BESSs, compensating for the negative impacts of VRE on operating costs, power generation reliability …


A Comparative Study On Artificial Intelligence-Based Methods For Fault Detection, Classification, And Localization In Distribution Lines, Nanda Kumari Jan 2022

A Comparative Study On Artificial Intelligence-Based Methods For Fault Detection, Classification, And Localization In Distribution Lines, Nanda Kumari

Chulalongkorn University Theses and Dissertations (Chula ETD)

In recent years, supervised machine learning (SML) has demonstrated its effectiveness in pattern recognition and outcome prediction within datasets. The objective of this research is to develop an algorithm that utilizes SML classification and regression equation capabilities to accurately classify and locate faults occurring in electricity distribution lines. The proposed algorithm takes the measured values of electrical current and voltage at one end of the distribution line as input data and outputs the type of fault. The algorithm evaluates its performance by simulating the IEEE 14-bus power system using MATLAB and generating various types of faults at different locations and …


Effect Of Thiosulfate On The Passivation Of Zinc-Alloyed Anodes, (Z32120 And Z13000) At 80°C After 288h Immersion In 3.5% Nacl Solution, Thwelt Thinzar Zaw Jan 2022

Effect Of Thiosulfate On The Passivation Of Zinc-Alloyed Anodes, (Z32120 And Z13000) At 80°C After 288h Immersion In 3.5% Nacl Solution, Thwelt Thinzar Zaw

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this research, the inhibition of passivation on Zn alloys (Z32120 with Al) and Z13000 without Al) in artificial seawater (3.5% NaCl) mixing with different thiosulfate concentrations (100ppm, 150ppm, 200ppm) were investigated electrochemically after 288h immersion at 80°C and compared the results with that of testing without thiosulfate in the environment. According to the Potentiodynamic polarization test results, it is found that the presence of thiosulfate (S2O32-) in the solution hinders the passivation that was formed during the immersion of Zn alloys between 120h and 288h at 80°C in the absence of thiosulfate. Thiosulfate effect promotes Cl- penetration for not …


การพัฒนาระบบการวางแผนและติดตามผนังคอนกรีตมวลเบาด้วยแนวคิดโมเดลข้อมูลสารสนเทศอาคาร, กมลทิพย์ พรชัยธเนศกุล Jan 2022

การพัฒนาระบบการวางแผนและติดตามผนังคอนกรีตมวลเบาด้วยแนวคิดโมเดลข้อมูลสารสนเทศอาคาร, กมลทิพย์ พรชัยธเนศกุล

Chulalongkorn University Theses and Dissertations (Chula ETD)

แผ่นผนังคอนกรีตมวลเบาถูกนำมาสร้างเพื่อใช้สำหรับการแบ่งพื้นที่ภายในอาคาร ซึ่งมีความรวดเร็วกว่าการก่อฉาบผนังอิฐแบบทั่วไป การวางแผนแผ่นผนังมักจะใช้การถอดปริมาณจากพื้นที่ผนังอาคารที่ต้องการติดตั้งเทียบกับพื้นที่ของแผ่นผนัง โดยความแม่นยำของการคำนวณจำนวนแผ่นผนังขึ้นอยู่กับความชำนาญของผู้วางแผนที่ส่งผลให้ปริมาณแผ่นผนังแตกต่างจากการใช้งานจริง และการติดตามสถานะแผ่นผนังในปัจจุบันเป็นเพียงการติดตามโดยประมาณเฉพาะพื้นที่ที่ดำเนินการแล้วเสร็จเทียบกับพื้นที่ทั้งหมดซึ่งระบุเป็นร้อยละ ดังนั้นการระบุสถานะและรายละเอียดแผ่นผนังในตำแหน่งต่างๆ ไม่สามารถทำได้อย่างตรงจุด บทความวิจัยนี้มีวัตถุประสงค์เพื่อนำเสนอระบบการวางแผนติดตั้งแผ่นผนังคอนกรีตมวลเบา เพื่อลดระยะเวลาในการวางแผนและเพิ่มความแม่นยำในการคำนวณจำนวนแผ่นผนัง รวมถึงพัฒนาเครื่องมือในการติดตามสถานะ เพื่อระบุตำแหน่งที่ติดตั้งและแก้ไขที่ชัดเจนของแผ่นผนัง โดยระบบที่พัฒนาประยุกต์ใช้แนวคิดโมเดลข้อมูลอาคารสารสนเทศสำหรับการเตรียมการติดตั้งแผ่นผนัง ซึ่งการพัฒนาระบบประกอบด้วยการกรองค่าโมเดลแผ่นผนังผ่าน Dynamo Code การวางแผ่นผนังในโมเดลอาคาร การแสดงผลข้อมูลผ่านโมเดลสามมิติ การเตรียมข้อมูลเพื่อสร้าง Tag ของแผ่นผนัง การกำหนดแผนระยะเวลาของการติดตั้งผ่าน Dynamo Player ซึ่งเป็นเครื่องมือสำหรับกรอกข้อมูล การติดตามสถานะผ่าน Google Form การสรุปข้อมูลติดตามผ่านโมเดลสามมิติและสเปรดชีต ผลการวิจัยจากกรณีศึกษาพบว่าระบบการวางแผนและติดตามแผ่นผนังสามารถวางแผนผนังตามช่วงผนังอาคารได้อย่างถูกต้องทั้งในกรณีของการวางแผ่นผนังขนาดเดียวกันและกรณีของการวางผสมผสานของแผ่นผนังที่มีขนาดแตกต่างกัน โดยการติดตามแผ่นผนังสามารถแสดงภาพให้เห็นได้ชัดเจนและรวดเร็วกว่าการวางแผนในรูปแบบเดิม รวมถึงสามารถระบุตำแหน่งและสถานะแผ่นผนังได้อย่างชัดเจนและถูกต้องตามตำแหน่งที่วางแผ่นผนัง