Engineering Commons^™

Mouralherwaqh Coastal Wetland Road Crossing Da'luk, Pakunihanich Nicoli Martin

Cal Poly Humboldt theses and projects

The integration of Indigenous and Western science plays an essential role in Tribally led collaborations for land management. This process of woven sciences is rooted in reciprocal relations and partnerships guided by Tribal Nations. Our cohort was invited by Wiyot Tribal Representatives to investigate a culvert located within the wetlands of Mouralherwaqh— a parcel of land reacquired by the Wiyot Tribe in 2022. This document seeks to share our experience and analysis as part of the Wiyot Tribe’s broader journey in navigating ecocultural restoration projects within Mouralherwaqh. The four community interests we investigated for the wetland crossing included a resized …

Mouralherwaqh Coastal Wetland Road Crossing Da'luk, Romel Robinson Ii

Cal Poly Humboldt theses and projects

The integration of Indigenous and Western science plays an essential role in Tribally led collaborations for land management. This process of woven sciences is rooted in reciprocal relations and partnerships guided by Tribal Nations. Our cohort was invited by Wiyot Tribal Representatives to investigate a culvert located within the wetlands of Mouralherwaqh— a parcel of land reacquired by the Wiyot Tribe in 2022. This document seeks to share our experience and analysis as part of the Wiyot Tribe’s broader journey in navigating ecocultural restoration projects within Mouralherwaqh. The four community interests we investigated for the wetland crossing included a resized …

Two-Dimensional Hydrodynamic Model Comparison For Fish Habitat Assessment In Rivers, Tyler Caseltine

Cal Poly Humboldt theses and projects

Accurate prediction of aquatic habitat availability for salmonids and other aquatic species is crucial for effective river and tributary restoration and management. Two-dimensional (2D) hydrodynamic models have become the standard for simulating depth and velocity conditions in open channel systems, leveraging advances in computational capabilities and spatial data collection. This study compares four 2D hydrodynamic models—SToRM, River2D, HECRAS2D, and SRH2D—using consistent topographic and calibration data, and adhering to Quality Assurance and Quality Control (QA/QC) standards as outlined by the US Fish and Wildlife Service (USFWS) and McBain Associates. The models were evaluated with data from two study sites for their …

Co-Firing Of Lpg And Diesel Fuels Through An Innovative Double Swirl Burner: Combustion Characteristics And Exhaust Emissions, Eslam O. Mater, Karim M. Soliman, A. Abdulnaim, Ahmed Abdelrazik Emara, Ahmed Salah Elsahy, Hany A. Moneib

Trends in advanced sciences and technology

The current stringent environmental regulations, the depletion of fossil fuels and the emergence of oil biofuels and synthetic gases had motivated combustion scientists to search for alternative technologies that meet efficient burning, flexible use of multiple fuels and conform to a clean environment. In that respect, several developments had emerged including, low swirl combustion for partially premixed mixtures, “Mild” combustion for diffusion flames. The present experimental study introduces a new concept that combines separate admissions of fuel and air with a central recirculation zone following the diffusion combustion mode, partial premixing within a premix chamber resulting in the creation of …

Air Jet Assisted Combustion Of Oil Diffusion Flames: Effects Of Injection Location And Excess Air Factor, Moustafa Ahmed Gamaleldin, Neama Youssef Ramadan, Ahmed Mohamed Abdulnaim, Ahmed Abdelnasser Adam, Ahmed Abdulrazik Emara, Hany Ahmed Moneib

Trends in advanced sciences and technology

This study investigates a novel methodology for a coaxial disc stabilized burner with a central jet oil spray. It introduces multiple air injection jets within the burner gun's exit section, promoting earlier fuel vaporization and rapid fuel-air mixture formation in the premixing zone. This directly contributes to improved overall combustion efficiency and reduced exhaust emissions. The focus lies on identifying the optimal location for the air injection jets (fixed load, constant jet momentum, and angle) within the exiting premixing zone of the burner gun. In-flame measurements are conducted inside a cylindrical combustor at different air injection locations and varying excess …

Dynamic Analysis And Experimental Verification Of Flexible Unbalance Rotor Supported By Two Identical Journal Bearings, Omar Ahmed, Hussein Sayed, T.A. El-Sayed

Trends in advanced sciences and technology

Abstract BACKGROUND: Analyzing the vibrations for rotor-bearing systems is a critical issue in the field of rotor dynamics. It is crucial to identify rotary machine vibrations, behaviors, and stability conditions. The main causes of vibration in rotating machinery are unbalanced masses, misalignment, mechanical looseness, shaft cracks, and other defects. METHODS: This paper investigates the experimental verification of a theoretical model, using a steel shaft with a disc set at the midpoint, supported by two symmetric fluid film bearings. The study examines the effect of unbalance on the dynamic behavior of the rotor and its vibration characteristics. The experimental investigation involved …

What Can We Learn From A Co-Creation Journey For A Quick Scan Digital Transformation Maturity Assessment Tool For Development Ngos?, Anand Sheombar

Journal of International Technology and Information Management

This paper describes the approach and lessons learned from a co-creation process with Dutch development NGOs to create a practical and easy-to-use assessment tool for practitioners to assess the organisation's maturity level of digital transformation. For this study, we applied a design science research methodology, specifically a six-step co-creation approach suitable for developing maturity models. The digital maturity assessment tool (quick scan) created is a domain- specific digital transformation maturity tool for development NGOs rather than a generally applicable tool. This artefact was evaluated using an eight-point Requirements framework for the development of digital maturity assessment tools. By developing a …

Fretting Corrosion Wear Of Titanium-Based Alloy (Ti-6al-4v) In 0.9 Wt.% Nacl Solution, Chen-En Lu, Wen-Ken Li, Hung-Hua Sheu, Jeou-Long Lee, Hung-Bin Lee

Journal of Marine Science and Technology–Taiwan

In this study, a high precision fretting tribo-corrosion tester used to analyze the wear and corrosion behavior of Ti alloys in a fretting motion condition. The tester, operated in a ball-on-plate mode, was employed in the fretting corrosion study of metallic bio-materials (Ti and Ti-6Al-4V) under different loads (0 and 10 N), electrolytes (0.9 wt% NaCl and SBF) and fixed displacement frequency (1 Hz). Using profilometer, optical microscope in the experimental analysis and three-body mechanism in the theoretical analysis, the fretting corrosion performances of these bio-medical metals, such as velocity accommodation characteristics, friction, wear, and scratch profile were examined in …

A New-Type Deep Learning Model Based On Shapley Regulation For Containerized Freight Index Prediction, Yen-Chang Shih, Ming-Shue Lin, Taih-Cherng Lirn, Jih-Gau Juang

Journal of Marine Science and Technology–Taiwan

In this study, we have crafted an innovative methodology that represents a groundbreaking synthesis of deep learning techniques with cooperative game theory. In this study, we use the accuracy of data prediction by different LSTM models as a measurement index and assign different LSTM models corresponding weights through the Shapley value calculation method to construct a more accurate predictive analysis model. We use this improved Shapley regulation model to calibrate a long short-term memory (LSTM) neural network by using historical freight data to predict the China Container Freight Index (CCFI), the leading export container freight index commonly used in China. …

Applicability Of Reducing Valve Timing Overlap For Diesel Engines Under High Exhaust Back Pressure, Chien-Cheng Chen, Yuan-Liang Jeng, Shun-Chang Yen

Journal of Marine Science and Technology–Taiwan

The exhaust back pressure of diesel engines becomes increasing higher nowadays. As an example, the De-NOx system and DE-SOx system necessitated by the increasingly stringent emission standards, would result in increased exhaust back pressure for those diesel engines adopting such systems. Some ships adopt underwater exhaust system to save space on the working deck and to reduce noise and air pollution, while the hydrostatic pressure under water level has made the exhaust back pressure of diesel engines getting much higher. Under high exhaust back pressure, to keep discharging exhaust unhindered and operating smoothly for diesel engine, it often results in …

Elimination Of Noise In A Ship Cabin Using Multi-Layered Acoustic Boards: An Apso And Sa Approach, Min-Chie Chiu, Ho-Chih Cheng

Journal of Marine Science and Technology–Taiwan

A high level of noise, combined with pure tones, is often encountered in ship's cabins, leading to severe psychological and physiological issues for the crew. To address this problem, an indoor noise abatement solution becomes necessary that utilizes efficient acoustic boards integrated with resonators, positioned along the inner walls of the cabin. However, the thickness of the acoustic boards must be strictly limited due to maintenance and operational considerations. This limitation results in insufficient sound absorption capabilities and a restricted range of tuned frequencies, as the resonating frequency of a standard Helmholtz resonator is closely tied to its cavity. A …

Numerical Study On The Aerodynamic Performance Of Four Flettner Rotors By Varying Distance And Spin Ratio, Janghoon Seo, Dong-Woo Park

Journal of Marine Science and Technology–Taiwan

The Flettner rotor is a wind-assisted propulsion system applied in eco-friendly ship to reduce greenhouse gas emissions. As the requirements of international regulations on greenhouse gas emissions become increasingly strict, multiple Flettner rotors are being applied, necessitating the evaluation of their performance with varying design parameters. The present study focuses on the aerodynamic performances of four Flettner rotors with variable design parameters of distance and spin ratio. Distances and spin ratios, including relative spin ratios, are considered. The drag and lift coefficients and lift-to-drag ratio of Flettner rotors are determined using Computational Fluid Dynamics (CFD), and the associated flow fields …

Underwater Image Enhancement Algorithm For Dual Color Spaces, Xingsheng Shen, Yalin Song, Shichang Li, Xiaoshu Hu

Journal of Marine Science and Technology–Taiwan

Targeting issues related to low contrast, blurring, and loss of detail prevalent in underwater image enhancement algorithms, we propose a dual-color space multiscale residual network (DMR-SCNet) based on SCNet. First, we introduce the HSV color space feature extraction module, which aims to optimize the color representation and saturation of underwater images. Subsequently, we propose the RGB color space denoising module, which focuses on repairing the content and structure of underwater images to enhance their clarity and visual quality. Finally, by designing the residual attention (RAB) module, we aim to further refine the detailed representation and feature extraction of underwater images. …

A Novel Identity Authentication Mechanism For Unmanned Maritime Vessels Communication Based On Mitre Att&Ck Framework, Junxian He, Shih-Hao Chang

Journal of Marine Science and Technology–Taiwan

With the development of the smart shipping industry, unmanned vessel technology is rapidly evolving, accompanied by a demand for robust Internet of Things (IoT) communication security practices. Key communication technologies for the operation of unmanned vessels include external vessel communication. One crucial aspect is the verification of the identities of the parties involved in these communication systems, as this ensures secure and trusted interactions between unmanned vessels and port management authorities. Identity authentication plays a vital role in ensuring the secure communication of unmanned vessels.This paper aims to analyze potential risks related to identity authentication technology in unmanned vessel communication …

Corrigendum To “Applicability Of Reducing Valve Timing Overlap For Diesel Engines Under High Exhaust Back Pressure”

Journal of Marine Science and Technology–Taiwan

No abstract provided.

Distribution And Population Structure Of Corallivorous Drupella Snails In The Coral Reefs Of Kenting In Taiwan, Chih-Jui Tan, Dun-Ru Kang, Li-Lian Liu

Journal of Marine Science and Technology–Taiwan

The corallivorous Drupella snails are common predators of living hard corals in the Indo-Pacific Ocean, and they can significantly threaten coral reef ecosystems when outbreaks occur. In Taiwan, a Drupella outbreak, which resulted in the dramatic decline of Acropora and Montipora corals, was reported in Penghu in 2002 – 2009. However, the Drupella species involved was not identified, and no further research has been conducted. To obtain current knowledge on the predation pressure of corallivorous snails on hard corals, we investigated benthic communities and the distribution and population structure of Drupella snails in the coral reefs of Kenting, Taiwan. The …

Evaluating The Connectivity Reliability Of The Seaborne Transportation Network Using Uncertainty Theory, Tianshou Liu, Haiyang Bian, Lin Feng, Chenyang Fan, Chaojun Ding, Grifoll Manel, Hongxiang Feng

Journal of Marine Science and Technology–Taiwan

The shipping network serves as the backbone of international trade. However, due to unstable geopolitical conditions, unexpected events have occurred frequently in recent years that have impacted the global shipping supply chain, and this has placed enormous pressure and had adverse effects on seaborne transportation. To measure the reliability of the global shipping network under unexpected events, we abstract the global shipping network into a small world network using uncertainty theory. A method is proposed for selecting (i) the optimal reliable path and (ii) the optimal reliable path with a maximum measurement under different confidence intervals. Our approach is then …

Mechanical Property Analysis And Three-Dimensional Reverse Reconstruction Based On Corrosion Pit Characteristics Of Strong Corrosion Steel Plate, Qiujun Ning, Xiaosong Lu, Jiawei Lu

Journal of Marine Science and Technology–Taiwan

To investigate the strong corrosion effect of 36% industrial hydrochloric acid on Q370 steel for bridges at room temperature. The surface morphology variations of the Q370 steel for bridges with corrosion time were measured and analyzed using a three-dimensional non-contact scanning profilometer. Subsequently, the standard monotonic tensile test was carried out to obtain the load-displacement curve and analyze the mechanical properties of the heavily corroded steel. Moreover, the constitutive model parameters of the heavily corroded steel were optimized. Furthermore, the heavily corroded steel model base on the actual corroded surface morphology was established, employing three-dimensional reverse reconstruction technology and finite …

Sea Ice Identification And Risk Assessment For Navigation In Ice Regions Based On Shipboard Camera Images, Tsung-Hsuan Hsieh, Xuan Lu, Shengzheng Wang, Wei Liu, Jianan Luo

Journal of Marine Science and Technology–Taiwan

In order to guarantee the safe navigation of vessels in icy regions and effectively capture sea ice risk information surrounding ships, this study introduces a sea ice identification and risk assessment process utilizing shipboard camera images. Firstly, based on the distribution characteristics of sea area, a hierarchical region segmentation algorithm is proposed to precisely remove interference factors and extract the region of interest. Then, a multivariate K-means clustering algorithm is proposed to classify sea ice classes based on various characteristics, including spatial similarity, sea ice area, sea ice thickness, gray scale, and other multivariate information. Finally, a method for small …

Optimization On Container Drayage Scheduling In Stochastic Time-Dependent Network, Qi Xu, Jie Huang, Xingyue Chen, Rui Cheng, Xiangyu Yin, Zhongzhen Yang

Journal of Marine Science and Technology–Taiwan

To ensure a reliable operation of container drayage transport system, this paper investigates the drayage scheduling problem in a stochastic time-dependent network. Based on the theory of the robust optimization, a mathematical model considering the attributes of “synchronized operation of multi machines” is built with the aim of minimization of the schedule delay in the whole system. A Simulated Annealing algorithm with Embedded Heuristics (SAEH) is designed for model solution. Comparisons between the results from the robust optimization and traditional expected value approach, and the results from the SAEH and CPLEX are conducted. Based on that, the effectiveness of our …

Offshore Vertical Axis Wind-Photovoltaic Power Plants: Development And Case Study, Victor V. Cheboxarov, Pavel N. Kuznetsov, Shun-Han Yang, Shiu-Wu Chau

Journal of Marine Science and Technology–Taiwan

This paper examines the potential for the development and implementation of hybrid wind-solar power plants utilizing large-scale offshore vertical-axis wind turbines. The proposed solution aims to increase energy production and reliability through the integration of photovoltaic modules directly into the wind turbine structure. Schematics of photovoltaic modules on the upper annular surface of the respective wind turbine are considered. The operation of the hybrid power plant is described. Equations to estimate the power characteristics of the plant are given. The case study analyzes the potential energy production of a hybrid marine power plant with a diameter of 200 m at …

Harvest By Autoflocculation, Biomass, And Carotenoid Production In Sequential Batch Culture Of Haematococcus Pluvialis Under High Ionic Strength And Macroelements Content, J. Galán-González, I. Quintero-Zapata, M Elías-Santos, L.J. Galán-Wong, U.J. López-Chuken, C Guajardo-Barbosa, J.C Beltrán-Rocha

Journal of Marine Science and Technology–Taiwan

Haematococcus pluvialis is a microalga with significant potential due to its capacity to produce carotenoids with antioxidant and nutraceutical benefits. However, the cost of harvesting this microalga, constituting over 30% of total expenses in large-scale production, is a major concern. Efficient flocculation, aiding in cell separation from the culture medium, is crucial to address this issue. The study contrasted Bold’s Basal Medium (BBM) with Lopez-Chuken & Young nutrient solution (LC-Y). The heightened salt content in LC-Y plays a crucial role in fostering saline stress, which is essential for evaluating H. pluvialis flocculation, biomass yield, and carotenoid production. To assess stability …

Research Progress On Ship Trajectory Prediction In Marine Transportation, Xiangen Bai, Kai Ye, Xiaofeng Xu

Journal of Marine Science and Technology–Taiwan

The prediction of ship navigation trajectories is crucial for ensuring maritime navigation safety and forecasting risk. In recent years, extensive research has been conducted on the prediction of ship navigation trajectories at home and abroad, and some results have been achieved. At present, most research on ship navigation trajectory prediction relies heavily on automatic identification system (AIS) data and the historical trajectories of ships. This study first reviews the research background and current situation of ship navigation trajectory prediction. Second, it provides an overview of ship navigation trajectory prediction, with an emphasis on sorting out and elaborating on artificial intelligence …

Numerical Investigations On Particle Collection And Discharge Of Rounded Rectangle Aquaculture Tank In Dual-Diagonal-Inlet Layout, Xiaozhong Ren, Shupeng Du, Hangfei Liu, Xianying Shi, Meng Li, Xian Wang, Suping Liu

Journal of Marine Science and Technology–Taiwan

To improve the space utilization rate of aquaculture tanks in aquaculture facilities and investigate the effect of the length-width ratio parameter (abbr. L/W, with L being the length of the tank and W being its width) on the particle collection and discharge characteristics of the rounded rectangle aquaculture tank with diagonal double inlet pipes. The study simulates the particle discharge procedure of the tank using a solidliquid two-phase numerical model (discrete phase model and RNG k-ε turbulence model adopted). The validity of the numerical model was confirmed through physical experiments. The simulation results for two jet condition indicate that when …

On The History And Semantics Of Burble In Aerodynamic Theory, Benjamin C. Moulton, Cory D. Goates, Troy A. Abraham

Mechanical and Aerospace Engineering Student Publications and Presentations

The term burble has been in use in aerodynamic theory for over a century. While burble may be unfamiliar to most contemporary aerodynamicists, the word has a rich history based in aerodynamic theory and experimentation. The present paper outlines the fluidity of burble's meaning over time. From analyzing subsonic flow over an airfoil, to the implementation of stochastic turbulence in aircraft carrier landing simulations, the term burble has had a significant impact on the study of aerodynamics. The term burble has fallen out of use in aerodynamic engineering circles. Why did this happen? And what can be learned from the …

Photoluminescence Switching In Quantum Dots Connected With Fluorinated And Hydrogenated Photochromic Molecules, Ephraiem S. Sarabamoun, Jonathan M. Bietsch, Pramod Aryal, Amelia G. Reid, Maurice Curran, Grayson Johnson, Esther H. R. Tsai, Charles W. Machan, Guijun Wang, Joshua J. Choi

Chemistry & Biochemistry Faculty Publications

We investigate switching of photoluminescence (PL) from PbS quantum dots (QDs) crosslinked with two different types of photochromic diarylethene molecules, 4,4'-(1-cyclopentene-1,2-diyl)bis[5-methyl-2-thiophenecarboxylic acid] (1H) and 4,4'-(1-perfluorocyclopentene-1,2-diyl)bis[5-methyl-2-thiophenecarboxylic acid] (2F). Our results show that the QDs crosslinked with the hydrogenated molecule (1H) exhibit a greater amount of switching in photoluminescence intensity compared to QDs crosslinked with the fluorinated molecule (2F). With a combination of differential pulse voltammetry and density functional theory, we attribute the different amount of PL switching to the different energy levels between 1H and 2F molecules which result in different potential barrier …

A Structure From Motion Photogrammetric Method For Continuously Measuring And Tracking The Deformations Of Soils During Triaxial Testing, Xiaolong Xia

Doctoral Dissertations

"Measuring soil deformation characteristics during triaxial testing is an important part of characterizing the stress-strain behavior of both saturated and unsaturated soils. The total and local deformations and volume changes of a soil specimen are indispensable parameters that need to be measured and are of great significance for understanding volume change and shear strength characteristics of the soil. Over the past several decades, numerous efforts have been made to measure the soil deformations during triaxial testing. However, it remains a great challenge for researchers to measure the volume-changes of unsaturated soils due to the existence of the air phase.

This …

Comprehensive Investigation Of Using Tire-Derived Aggregate In Chip Seal Subjected To Various Traffic And Environmental Conditions, Alireza Pourhassan

Doctoral Dissertations

"Chip seal is one of the most cost- and performance-effective pavement preservation treatments commonly used in the United States. Using crumb rubber obtained from scrap tires as a partial or full replacement for mineral aggregate has been proposed as a sustainable solution to reduce the negative environmental impacts of scrap tire accumulation and excessive consumption of natural resources. However, there was no data available regarding the performance of rubberized chip seal under traffic loads and environmental conditions. An extensive study using laboratory specimens and conditioning as well as field implementation and assessments were conducted to bridge this gap. Different traffic …

Sustainable Cementitious Materials For Building And Sorption Applications, Sukanta Kumar Mondal

Doctoral Dissertations

"Ordinary Portland Cement (OPC) is the most widely used cement material, but it contributes over 8% of the global CO₂ emission and the process is energy intensive. Moreover, OPC faces durability challenges, particularly in aggressive environments. Hence, there is rapidly increasing interest in sustainable alternative cements with lower carbon footprint, lower energy consumption, and those that offer superior properties that are beneficial for specific applications. Two sustainable cementitious materials that are frequently researched as an alternative to OPC are calcium sulfoaluminate (CSA) cement and alkali-activated materials (AAMs). CSA cement lowers CO₂ emission by over 40% compared to OPC, …

Novel Supercritical Biodiesel Plant Design & Process Scale-Up, Ghana Shyam Paudel

Doctoral Dissertations

"Current energy prices, national energy security, and global climate change fuel our momentum to find efficient advanced fuels choices. In this study, biodiesel processing, and a novel design for next generation biodiesel plants are explored. During a National Science Foundation (NSF) I-Corps project we identified three creative and profitable improvements to the process: 1. Incorporating Energy intensive separations and reactions 2. Utilizing Low commodity glycerol and 3. Applying process intensification principles.

Current biodiesel processes are catalyzed processes using continuous stir reactors with distillation systems to separate material constituents. We tested a lab-scale nocatalyst supercritical biodiesel process using waste cooking oil …