Digital Commons Network^™

Some Initial Results Of Field Trials Conducted In Establishing A Pasture-Seed Industry In Cojedes State, Venezuela, E.J A. Khan, W H. Mark

IGC Proceedings (1977-2023)

In starting a pasture-seed industry on a farm located at lat 9°50' N that gets about 1,600 mm of rain yearly followed by a severe dry season from mid-December to April, four widely separated sites were selected to plant three grasses for commercial seed production in 1978. The objectives were to assess the fertility status of the soils, then to determine the fertilizer re­quirements of the grasses at each site and to establish an introduction garden with 70 cultivars of grasses and legumes to study their suitability for expanding seed production. Based on the results of soil analyses, a modified …

Insect Pests Of Tropical Forage Plants In South America, Mario Calderon

IGC Proceedings (1977-2023)

The objectives of this continuing research are to make a general survey of the insect populations occurring on tropical forage plants in South America and to identify the most important pests. To realize this investigation, pure stand plots 5 X 5 m were sampled every 14 days during 2 years using a D-Vac. Vacuum Sampler.

The following information was obtained:

• Most important families and/or genera of insects in tropical forage legumes and grasses. • Insect group frequency for each season. • Insect group frequency for each plant ecotype under study. • Preliminary data on insect preference. • Preliminary data …

Sown Grassland As An Alternative To Shifting Cultivation In Lowland Humid Tropics, H R. Chheda, O Babalola, M.A M. Saleem, M E. Aken'ova

IGC Proceedings (1977-2023)

Agriculture based on existing forms of shifting cultivation will not be able to support and feed adequately the rapidly increasing human population of the lowland humid tropics of Africa. The forest and natural fallows have shortened and even disap• peared in some areas because of rising food demands. Crop yields are low and continue to decline. What, then, are the alter­natives? Using Cynodon as an example, an attempt is made to show that mixed farming offers an alternative whereby the nutrient status and physical properties of the soil can be maintained, erosion can be checked, weeds can be kept under …

Animal Production From Brazilian Tropical Pastures, G L. Rocha, V.B G. Alcantara, P B. Alcantara

IGC Proceedings (1977-2023)

This review deals with the potential for beef production from nitrogen- and legume-based pastures in tropical Brazil. Possibilities for impr􀀞ving the beef industry supported by grass-legume pastures are very promising. According to the literature examined, legume-based pastures produced an annual average of 329 kg gain/ha, and nitrogen (N) fertilization resulted in 4.56 kg gain/ha. Phosphorus (P) was the main fertilizer utilized in addition to N, followed by potassium (K), lime, and micronutrients. An­nual rainfall averaged 1430 mm. Grasses used were of the genera Melinis, Hyparrhenia, Panicum, Cenchrus, Digitaria, Cynodon, Brachiaria, and Pennisetum, and the legumes were of the genera Macroptilium, …

Verano Stylo In Semiarid Northeastern Thailand, A Topark-Ngarm

IGC Proceedings (1977-2023)

Srylosanthes hamata cv. Verano was first introduced to Thailand in 197 5. In the northeastern part of the country where the climate is marginal and the soils are low in fertility, Verano appears to be one of the most suitable forage legumes used in pasture-improvement programs. Verano can be grown satisfactorily on most soils in the northeast. Oversowing the seed at 3.1 kg/ha on unploughed areas resulted in a density of 5-30 plants/m2, while in cultivated land the same amount of seed gave 20-45 plant/m2 • In a 3-year ex­periment under different seeding rates and cutting intervals Verano outyielded three …

Hemarthria Altissima: A Pasture Grass For The Tropics, K H. Quesenberry, W R. Ocumpaugh, O C. Ruelke

IGC Proceedings (1977-2023)

Limpograss (Hemarthria altissima [Poir] Stapf. et C.E. Hubb), introduced into the U.S. in 1964, has been evaluated for use as a pasture grass. Under Florida conditions it has shown yield potential equal to or greater than other tropical pasture grasses. The cultivar Bigalta has higher in-vitro organic-matter digestion (IVOMD) than other tropical grasses at comparable growth stages. Early evaluations of limpograss involved only three clones, but additional genotypes were collected and introduced during the late 1960s and early 1970s, and an evaluation scheme for this germ plasm was undertaken. Our objectives were to evaluate rapidly the available germ plasm of …

The Dynamics Of Educational Change: A Complex Systems Perspective, Preethi Nanjundan, Lijo Thomas, Abith K. Sunil

Northeast Journal of Complex Systems (NEJCS)

The perception of university teachers toward educational reforms plays an important role in determining the success of changes introduced in the education sector. This study focuses on teachers’ attitudes toward change, their emotional responses, and their overall views on educational reforms. Across the world, many educational reforms have failed to achieve their expected outcomes in improving teaching practices and student learning. As education systems are highly complex, the approach toward implementing reforms has also changed over time. Some reforms are introduced gradually, while others involve major innovations within the system. Complexity theory provides useful insights and tools that help educators …

The Effect Of Weight Training With Blood Flow Restriction On Muscle Strength Development In Mma, Tomáš Kozák, Marek Kokinda, Pavel Ružbarský

Baltic Journal of Health and Physical Activity

Background: This study aimed to elucidate the effect of weight training with blood flow restriction (BFR) on explosive power and isokinetic strength in combat athletes. Materials and methods: The sample included 12 male MMA fighters divided into a control (19.50±0.50 years) and an experimental (18.00±1.00 years) group. Participants trained twice weekly for 8 weeks, with BFR in the experimental group. Explosive power was assessed using following tests by Optogait: countermovement push-up, kneeling countermovement push-up and kneeling squat push-up for upper limbs and countermovement jump, countermovement jump with free arms and squat jump for lower limbs. Isokinetic strength was measured by …

An Intelligent Packaging Materials Management And Optimisation For The Production Process, A. Abdulkareem, C. O. Ijagbemi, B. Kareem

The Journal of Engineering Research

An intelligent model was formulated to aid in the packaging materials management and optimisation for the production process. This was done after generating a 2D drawing using AutoCAD software for each of the popular packaging material shapes utilised in the production system. In modelling, uniform (regular) and non-uniform (irregular) packaging containers were considered in the determination of forces, areas, volumes, weights, densities, among other relevant parameters. Three packaging materials: ceramic glass, plastic and laminated cardboard containing processed water and other beverages in 75 cl, 50 cl, 33 cl and 1 litre respectively were considered during model testing. Results showed that …

Effect Of Changing Properties Of In-Pipe Inspection Robot And Payload Capacity On Its Performance, Sarra Gismelseed, Amur Al-Yehmadi, Riadh Zaier, Mojtaba Ghodsi

The Journal of Engineering Research

The performance of screw-drive in-pipe inspection robots is significantly influenced by factors such as wheel tilting angle, coefficient of friction, and spring constant. A comprehensive understanding of these parameters is critical for the effective design, optimization, and control of the robot, particularly to enhance energy efficiency and payload capacity during vertical pipeline inspections. In this study, we developed a mathematical model based on discrete Lagrangian mechanics to formulate an optimization problem aimed at minimizing power consumption and maximizing payload capacity under various dynamic constraints and design conditions. Our results show that increasing the wheel tilt angle allows the robot to …

The Online Spsg Parameters Prediction With Endorsement Based On Fem And The D-Q Model, Ahmed H. Ahmed, Basil M. Saied

The Journal of Engineering Research

The aim of this research is to present a method of online parameter estimation for a salient-pole, three-phase synchronous generator. Two main approaches have been used, based on different theories, to prove the validity of parameter estimation results. The first approach is based on the representation of synchronous machines using the d-q model with the sequence of the Hartley Series function and the finite element model (FEM). Therefore, two sets of parameter estimation results have been predicted. In the second approach, where the synchronous machine has been represented in real form, and the obtained results have been analysed to obtain …

Papr Reduction For Ofdm-Over-Noma Using Hybrid Partial Selective Mapping And Artificial Neural Networks, Tamadhar Al-Hashmi, Naser Tarhuni, Mostefa Mesbah, Hafiz Asif

The Journal of Engineering Research

Orthogonal Frequency Division Multiple Access (OFDMA) combined with Non-Orthogonal Multiple Access (NOMA) represents a promising hybrid approach for next-generation wireless communication systems. By leveraging the strengths of both OFDM and NOMA, this integration aims to improve system capacity and spectral efficiency while supporting Ultra-Reliable Low-Latency Communications (URLLC) for a wide range of devices. Despite its potential, one major limitation of this technology is the high peak-to-average power ratio (PAPR), which can negatively impact system performance. Traditional methods for PAPR reduction, such as Selective Mapping (SLM), rely on searching for optimal phase rotations across all subcarriers, but these methods are computationally …

Efficient Fault Detection In Nonlinear Industrial Processes: A Reduced Kernel Pca-Based Spectral Clustering Approach, Khadija Attouri, Majdi Mansouri, Abdelmalek Kouadri

The Journal of Engineering Research

Kernel Principal Component Analysis (KPCA) is a powerful tool for nonlinear process monitoring, yet its quadratic computational complexity (O( N² )) and high memory demands limit its applicability to large-scale industrial systems. This paper proposes a novel Reduced Kernel Principal Component Analysis based on Spectral Clustering (RKPCA_SpC) paradigm to efficiently address these limitations. For comprehensive comparison and to demonstrate the general efficacy of data reduction, an RKPCA_Kmeans variant is also developed and evaluated. The proposed and comparative methods are rigorously assessed through extensive case studies on two complex industrial processes: the Tennessee Eastman Process (TEP) …

Steady-State Performance Analysis Of Grid-Connected Windfarm Arrays With Mvdc Collection Networks, Esam A. Saafan, Ibrahim A. Metwally, Mohamed Eladawy

The Journal of Engineering Research

Recently, there has been an increased impetus worldwide to harness wind power to generate electricity on a large scale and integrate such systems into the existing electrical networks. In this paper, a mathematical model of a wind turbine with a horizontal axis, considering the drive train, is investigated to describe the wind turbine aerodynamics and the processes of mechanical energy conversion. The wind turbine characteristics are studied in two states, namely, a standalone turbine and a generator-connected turbine. The modelling of both states is performed using PSCAD/EMTDC. Steady-state analysis for a grid-connected wind system is performed at fixed and variable …

Spectral Unmixing Using Machine Learning, Debashis Dhar

Master’s Dissertations

Spectral Unmixing is an important field of study nowadays which focuses on gener ating fractional abundance of each pixel into constituent materials .In this thesis we have tried to unmix each pixel into three end members namely glacial lake,debris and others with primarily focusing on glacial lake.We have performed various meth ods of linear spectral unmixing and non linear spectral unmixing. These methods are applied on the collected LandSat Data of east Himalayan terrain .Experimental results demonstrate the effectiveness of the proposed approach in achieving high accuracy and efficiency in glacier lake tracking on LandSat data.

A Switch-Point-Aware Contrastive Approach To Sentiment Analysis Of Hinglish Code-Mixed Text, Prasant Kumar Sahoo

Master’s Dissertations

With the increasing use of social media in non-English-speaking regions, especially in India, people often use Romanized Hindi and English together in their online communication. In a single sentence, they frequently mix Romanized Hindi and English, creating code-mixed text. However, most multilingual transformer models are pre-trained primarily on monolingual data. As a result, NLP systems face challenges when processing code-mixed text, as a single word may be fragmented into meaningless subword pieces, making it difficult for the model to capture its semantic meaning accurately. In this dissertation, we propose a parameter efficient neural architecture consisting of three main components to …

Detection Of C60 Combination Bands In The Near-Ir Spectrum Of Tc 1, Morgan M. Giese, Vincent J. Esposito, Simon Van Schuylenbergh, Jan Cami, Els Peeters, Charmi Bhatt, Dries Van De Putte, A. G. G. M. Tielens, Michael J. Barlow, Jeronimo Bernard-Salas, Alessandra Candian, Bryan Changala, Nick L. J. Cox, Harriet L. Dinerstein, D. A. García-Hernández, Marco A. Gómez-Muñoz, Kay Justtanont, Kathleen E. Kraemer, Eric Lagadec, Arturo Manchado, Ana Monreal Ibero, Raghvendra Sahai, Ameek Sidhu, G. C. Sloan, N. C. Sterling, Jeremy R. Walsh, Roger Wesson, Joshua Cole Whitman, Albert Zijlstra

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We report the detection of a set of new near-infrared emission features between 3.5 and 5.2 μm in JWST/NIRSpec observations of Tc 1, the planetary nebula known for displaying the cleanest and most prominent mid-infrared cosmic fullerene spectrum. These broad features share the same spatial distribution as the well-known C₆₀ and C₇₀ mid-infrared emission bands, peaking in an asymmetric ring approximately 5″–6″ from the central star. Through comparison with new anharmonic quantum chemical calculations, we demonstrate that these features arise from C₆₀ combination bands, marking their first detection in an astrophysical environment. The total energy radiated …

Synthetic-Chicken-Fillets, Chirantan Sen Mukherjee, Seung-Chul Yoon, William J. Beksi

Agriculture

This Synthetic-Chicken-Fillets dataset contains 1,000 synthetic 3D meshes designed to capture the natural variance and size diversity of real broiler fillets. The collection was developed to test automated woody breast detection algorithms within a physics-based simulation environment. We utilized a seed dataset of 2D depth maps derived from 40 real-world RGBD point cloud scans. These real depth maps were fed into a few-shot transfer learning pipeline using a generative adversarial network architecture. The resulting generated depth maps were reconstructed back into 3D meshes. The length and thickness of each mesh were randomly scaled based on physical measurements of real broiler …

Extending Unibreak: Semantic Retrieval And Harmful-Intent Direction Suppression For Token-Level Llm Jailbreaking, Sanket Saha

Master’s Dissertations

Token-level adversarial perturbations remain one of the most efficient known attacks against the safety alignment of instruction-tuned large language models (LLMs). Among recent works, the UniBreak framework (You et al., 2026) stands out for unifying gradient-based optimization with an evolutionary perturbation repository. However, its repository relies solely on accumulated success frequency without utilizing query content, and its fitness function implicitly assumes that suppressing refusal tokens is sufficient to elicit harmful responses. In this dissertation, we extend UniBreak along both axes and re-evaluates the framework under stricter generalization and judgment protocols. Specifically, we introduce a semantic perturbation repository that replaces frequency-only …

The Effect Of Mwcnt-Oil Impregnation Of Sintered Components On Their Wear And Corrosion Resistance, Maha Khaled Abdelfadeel

Theses and Dissertations

Powder Metallurgy (PM) offers an advantageous route for manufacturing complex and near net-shape components. Their inherent interconnected porosity that promotes the action of self lubrication compromises their structural integrity by creating pathways for corrosion and excessive wear. This research investigates the efficacy of Multi-Walled Carbon Nanotubes (MWCNTs) as a nano additive within the impregnating base oil (SN-150 base oil). An experimental matrix was designed to evaluate the influence of MWCNTs with different concentrations of 0.05, 0.1, and 0.2 wt.% and ultrasonic dispersion with varying sonication times of 30 and 60 minutes on the tribological and electrochemical performance of sintered steel …

Engineering Nanoelectrocatalytic Systems For Co2 And Nitrate Conversion Into Value-Added Chemicals, Abdelrahman Mohamed Abdelmohsen

Theses and Dissertations

The thesis addresses two major related environmental crises: nitrate pollution of water systems and the ever-increasing levels of atmospheric carbon dioxide. Both challenges are closely linked to anthropogenic disturbance of nitrogen and carbon cycles and require sustainable, energy efficient mitigation techniques. In this study, we investigate electrochemical conversion routes as a unified approach to convert these pollutants into value-added compounds: ammonia (NH3) via nitrate reduction (NO3-RR) and ethylene (C2H4) via carbon dioxide reduction (CO2RR). The first half of this work deals with the design and engineering of Cu-Zn alloy electrocatalysts for efficient NO3-RR. Tuning the alloy composition and surface nanostructure …

Flexible-Mode Multi-Skilled Resource-Constrained Project Scheduling Problem With Setup Times: Application In The Oil And Gas Industry, Safinaz M. El Dawody

Theses and Dissertations

Turnaround maintenance (TAM) in the petroleum refining sector requires coordinating geographically dispersed project portfolios under stringent resource, schedule, and budget constraints. Conventional scheduling models treat tasks in isolation, failing to account for shared resources, crew fatigue, or inter-site transit. To bridge this gap, this study introduces and empirically validates a Flexible-Mode Multi-Skilled Resource-Constrained Project Scheduling Problem with Setup Times (FM-MS-RCPSP-ST). Applied to a real-world portfolio of 76 TAM projects across five governorates in Egypt, the framework is operationalized through an 11-stage pipeline integrating NSGA-II multi-objective optimization, GIS-based routing, and 500-trial Monte Carlo disruption simulations.

Results demonstrate that incorporating mandatory crew-rest …

Sense Of Belonging Among Undergraduate Students At The American University In Cairo: Demographic Trends, Barriers And Facilitators, Lamiaa M. Mohamed

Theses and Dissertations

A sense of belonging is widely recognized as a key determinant of undergraduate students’ academic success, well-being, and persistence in higher education. However, existing research is largely grounded in Western contexts and often emphasizes institution-level measures, with limited attention to how belonging is experienced and constructed by students in non-Western settings. This study examines undergraduate students’ sense of belonging at the American University in Cairo, focusing on factors that shape belonging and institutional practices that may strengthen it. Using a sequential mixed-methods design, the study examined 87 responses from a quantitative survey adapted from the University Belonging Questionnaire, followed by …

Tuning Ion Mobility And Molecular Confinement In High-Performance Polymer Electrolytes For Energy Storage, Ezzeldien Yousef Muhammed Yousef

Theses and Dissertations

This research addresses the critical energy density limitations of aqueous supercapacitors, which are traditionally constrained by the narrow electrochemical stability window (ESW) of water 1.23 V. By employing two distinct molecular engineering strategies, this study developed high-performance electrolyte systems that significantly extend voltage stability and thermal resilience.

The first system, CsBr@PAM/HA, utilizes a polyacrylamide and hyaluronic acid hydrogel matrix. This system exploits the chaotropic nature of Cs⁺ ions to disrupt the aqueous hydrogen-bonding network, enhancing ionic conductivity to 104 mS cm^-1. Through systematic salt screening, CsBr was identified as the optimal electrolyte, enabling a stable 2.0 V …

Parental Gender Bias In Youth Employment Standards: Evidence From Upper Egypt, Mahmoud Saeed

Theses and Dissertations

Youth unemployment remains a critical challenge in Egypt, with female labor force participation among the lowest globally. While structural factors such as limited job creation and public sector contraction are well-documented, the role of family-level decision-making in constraining women's labor market entry has received limited quantitative attention. This thesis examines parental gender bias in employment standards in Upper Egypt, investigating whether and how parents impose systematically different job requirements for daughters compared to sons. Using primary survey data from 17,284 unemployed youth aged 18-35 across six governorates, paired with responses from their parents, this study analyzes parental preferences across six …

Simultaneous Tumor Delineation And Report Generation From Brain Mr Images, Adish Mallik

Master’s Dissertations

Brain tumor analysis is an important application of medical image computing, where accurate segmentation and interpretation of tumor regions can support diagnosis and treatment planning. However, existing methods often address tumor segmentation and radiology report generation as separate tasks. Moreover, one of the major challenges in report generation tasks from MRI is accurate tumor localization. Most models fail to locate the lobe and hemisphere in which the tumor is located, causing incorrect report generation. In this regard, a unified 3D vision-language framework is proposed for simultaneous brain tumor segmentation and report generation from multi-modal MRI. Given T1, T2, T1C, and …

Ontology-Based Decision Support System For Improving Aquaculture Management, Thuy Thi Thu Pham, Phuong Thi Can, Nga Thi Thanh Ha

Journal of Marine Science and Technology–Taiwan

Early detection of shrimp diseases is vital for reducing losses and ensuring sustainable aquaculture. In this study, a novel ontology-driven framework for shrimp disease diagnosis that integrates environmental knowledge with machine learning-based image analysis is proposed. An ontology was constructed from a structured dataset of environmental parameters and farm conditions related to shrimp diseases, which formally represents concepts such as farm characteristics, environmental factors, symptoms, and disease types. Two public shrimp image datasets were subsequently used to train convolutional neural networks (ResNet50 and MobileNetV2) for automated disease classification. The predicted disease labels and confidence scores were mapped onto the ontology. …

Case Study On Operational Performance Improvement By Turbocharger Nozzle-Ring Modification In Shipboard Generators, Jong-Hun Im, Mukyeong Kang, Sang-Deuk Lee

Journal of Marine Science and Technology–Taiwan

Owing to increasingly stringent emission regulations imposed by the International Maritime Organization and rising fuel prices, the demand for enhanced energy efficiency and emission control in marine power systems is increasing. This study presents a case study in which the performance of an aging auxiliary generator is restored by modifying the turbocharger nozzle ring. The vessel, a 12-year-old crude-oil tanker, experienced repeated operational issues with its No. 3 generator. This included elevated exhaust gas temperatures, reduced intake air pressure, and frequent turbocharger surges. To address these challenges, the nozzle-ring blade angle was reduced by approximately 2° using spare components, while …

Towards Sustainable Marine Education: Assessing High School Students’ Understanding Of Conservation Concepts, Cheng-Chieh Chang, Tsuyoshi Sasaki, Ya-Yin Liao, Ling-Ya Hung, Liang-Ting Tsai

Journal of Marine Science and Technology–Taiwan

This study assesses the concepts of marine resource conservation and sustainability among Taiwanese high school students by developing a Chinese version of the Marine Resources Conservation and Sustainability Scale. Grounded in the cognitive, socio-emotional, and behavioral learning objectives outlined in UNESCO’s Education for Sustainable Development Goals (ESDGs), the scale targets students aged 16 to 18 to examine gender differences in marine knowledge and conservation concepts. The scale comprises 31 items across four dimensions: the first section evaluates marine knowledge, while the remaining dimensions utilize a four-point Likert scale to assess cognitive, socio-emotional, and behavioral learning objectives, respectively. The results indicate …

Dynamic Governance Of Transboundary Fisheries Through Deep Learning And High-Frequency Vessel Tracking Data For Climate-Resilient Management: An Application To The East China Sea, Qin Lin, Yaqing Shu, Manel Grifoll, Hongxiang Feng

Journal of Marine Science and Technology–Taiwan

Transboundary fisheries governance is increasingly challenged by jurisdictional conflicts, regulatory asymmetries, and climate-induced stock shifts in fish stocks, especially in contested regions like the East China Sea (ECS). This study capitalizes on China’s high-frequency BeiDou Navigation Satellite System (BDS) data (June 2021–May 2022) to pioneer a CNN-BiLSTM deep learning model to dynamically identify fishing hotspots and evaluate policy effectiveness. By integrating vessel trajectories, environmental variables, and regulatory events, we examine spatiotemporal patterns of fishing effort relative to seasonal bans, extreme weather, and quota systems. Key findings reveal: (1) post-moratorium (September–December) concentration of fishing intensity, peaking in November; (2) significant weather-driven …