13474 research outputs found
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Enhancing reservoir simulation models with genetic algorithm optimized neural networks across diverse climatic zones / Saad Mawlood Saab
No full textDams and reservoir systems help improve livelihoods, agriculture productivity, and farmers' drought resilience by regulating and increasing water supply reliability. In fact, the reservoir simulation depends on several hydrological parameters. Since hydrologic parameters exhibit a high degree of stochasticity, developing an accurate forecasting model that reproduces such a complex pattern is becoming increasingly challenging. A well-designed and reliable forecasting model is key to the successful reservoir simulation so as to maximize the use of water resources. Since the hydrological parameters are difficult to handle mathematically, existing prediction models are burdened with several drawbacks. The aims of the study are to develop robust models to predict two different parameters of hydrology in the dam reservoir and examine their performance under different climate conditions. Also, the study introduces a new procedure for reservoir simulation.
The current research presents three different AI approaches: i) Multi-Layer Perceptron Neural Network (MLP-NN), ii) Radial Basis Function Neural Network (RBF-NN), and iii) Deep Learning Neural Network (DLNN). The proposed models were utilized to predict two key hydrological parameters related to reservoir simulation: inflow and evaporation. The research improved the predictive models by integrating them with the Genetic Algorithm (GA). The optimizer algorithm (i.e., GA) determines the optimal input variables and internal parameters in the prediction models. To illustrate the models' efficacy, predictive models were applied to predict reservoir inflow and evaporation in two different case studies representing different environmental conditions, semi-arid and tropical case studies. The first case study is Dukan Dam, located in Iraq (semi-arid region), and the second is Timah Tasoh Dam (TTD), located in Malaysia (tropical region). Comparative analysis was performed between predictive models based on several statistical indicators. The prediction outcomes demonstrated that the GA-DLNN performs better than other proposed models. The GA-DLNN achieved well results in forecasting inflow values where it attained low (RMSE (23.49 m3/sec at Dukan, 2.92 MCM month-1 at TTD) MAE (15.55 m3/sec at Dukan, 2.06 MCM month-1 at TTD) and high correlation coefficient (R2 = 0.967 at Dukan, R2 = 0.969 at TTD). Also, the results indicated that the GA-DLNN achieved high level accuracy in prediction reservoir evaporation values, where it attained a low (RMSE (0.73 mm day-1 at Dukan, 6.77 mm month-1 at TTD) MAE (0.30 mm day-1 at Dukan, 3.87 mm month-1 at TTD) and high correlation coefficient (R2 = 0.976 at Dukan, R2 = 0937 at TTD) . On the other hand, the current study introduced a new procedure for simulating reservoirs under realistic conditions. This procedure was performed by including the prediction results obtained by the best and worst models in the balance equation. Reservoir condition assessment under new and conventional procedures was performed by calculating the percentage error during the simulation period. It was observed that the reservoir condition changed significantly with the inclusion of the predicted flow and evaporation data within simulation session. This research found that GA-DLNN method is better than alternative models put forth in predicting reservoir inflow and evaporation data. The predicted data should be adopted while performing the reservoir simulation
Employers’ perspectives on the employability of music graduates in Hefei, China / Xu Zitong
No full textFor all university graduates in today's society, employment represents a significant source of stress and challenge. A range of social and personal factors contribute to this stress. The objective of this study was to examine the perceptions of employers regarding the employability of music graduates in music education institutions in Hefei City. This study sought to address two key research questions: (1) How is the employability of current music graduates perceived by the employers of music education institutions? (2) What recommendations can be made to improve the employability of music graduates from the employers' perspective? Five employers were interviewed to ascertain their perceptions of the employability of music graduates. The interviews were conducted using a semi-structured approach and employed a categorization of employability into specialist skills and comprehensive employability. The present study examined employers' perceptions of the employability of music graduates, focusing on six key areas: professional competence, communication skills, adaptability, work attitude, career planning, and teamwork awareness. Employers were invited to offer their views and provide specific suggestions on how they expected graduates to develop their employability. Furthermore, employers concurred that the underemployment of music graduates is predominantly attributable to the deficiencies inherent in the institution's curriculum and training model. Consequently, employers articulated their discontent with the prevailing levels of employability exhibited by music graduates and underscored the necessity for uninterrupted enhancement to align with the competencies demanded by the role
Psychological experience of juvenile offenders in the correctional institutions in Indonesia / Jesika Juliana
Full text linkJuvenile offenders receive several disadvantages of their conditions. Therefore, the mental health needs of juvenile offenders are more prevalent than the general adolescent population. This condition worsens due to difficulties understanding their experiences from their own voice. This study aims to focus on the psychological experiences of juvenile offenders while residing in correctional institutions in Indonesia. Hence, the findings of this study can be implemented as a tool to increase awareness and provide in-depth information to improve their well-being. The qualitative method was conducted with a purposive sample of six juvenile offenders in three correctional institutions in Indonesia. Interpretative phenomenological analysis was utilized to identify recurring themes and patterns in the data. Six main themes emerged from the analysis: (1) dissatisfaction with family interaction; (2) emotional numbing; (3) restrictions in decision making; (4) having positive emotions about decision making; (5) transformation to positive behavior; (6) motivation to avoid crime. This study observes shifts and adaptations in psychological experiences over time, as well as the crucial role of juvenile offenders’ background, peers, staff, family members, and engagement in activities in the correctional institution. Further research is warranted to explore the post-release experiences of juvenile delinquents to examine whether the benefits of detainment were attained
Modelling and experimental verification of portable ultrafiltration system for drinking water production / Azman Ariffin
No full textUltrafiltration (UF) effectively removes contaminants to yield clean drinking water by allowing water to flow through a semipermeable membrane which incorporate microscopic pores ranging from 0.01 to 0.1 μm. To determine the effectiveness of the portable system, water quality analysis has been carried out to determine if the system produce filtered water from a river, lake and synthetic water source achieving the drinking water standards.
The parameters examined are turbidity, color, presence of bacteria and the Water Quality Index (WQI) value. The results show that this portable UF (PUF) unit produces purified water that meets quality standards, achieving reduction in turbidity from 24.4 NTU of river water to less than 1 NTU, reduction in colour from 300 TCU of river water to less than 15 TCU and the WQI being upgraded from Class II to Class I grade water, which is from 86% to 94% for river water. Moreover, the system demonstrates its ability to produce microbiologically safe drinking water by eliminating the total coliform along with all Escherichia coli (E-coli) bacteria that come from the raw water sources.
A simple model of the system using Darcy’s Law was also obtained to predict the permeate flux and transmembrane pressure (TMP). Initially, simulation was done using nominal value, as taken from the literature, four (4) parameters i.e. the membrane hydraulic resistance, initial rapid fouling constant, mass transfer coefficient and foulant bulk concentration. Using the Evolutionary Programming (EP) technique, an enhanced model with revised parameters was produced by reducing the error between the model with these nominal values and the experimental values. The four parameters were optimized as input variables and interaction among them was observed, while TMP and permeate flux were considered as response attributes. With the updated model, the average error between the model and experiment was reduced from 32% to 9%. This was further validated with new data taken from experiment. This improved model with the updated parameter was then used to predict the TMP and compared with the experimental value. Contrasting the optimized model with the existing model indicates that the optimized model predicts the membrane performance better, making it competent as a reliable model for the purification of water using the in-house built portable UF (PUF) system while meeting water quality standard and the United Nations Sustainable Development Goals (SDG) on Drinking water, everyone should have equitable and universal access to safe and affordable drinking water by the year 2030
Bright and dark pulsed fiber lasers based on multimode interference / Chen Yu
No full textPulsed lasers, particularly ultrashort pulsed lasers, find widespread application across various fields including telecommunications, bio-imaging, spectroscopy, atmospheric measurements, surgery, and material processing. This study focuses on harnessing the potential of the single mode-multimode-single mode (SMS) structure as a robust avenue for developing simple, compact, and cost-effective bright and dark pulsed erbium-doped fiber lasers (EDFLs). The SMS configuration serves as an ingenious artificial saturable absorber (SA), facilitating the generation of ultrashort pulsed lasers through the Kerr Effect with nonlinear multimode interference. By precisely fusion-splicing single mode fibers to both ends of a designated length of multimode fiber, the SMS architecture is established. Subsequently, integrating this SMS structure into a ring EDFL and finetuning parameters via a polarization controller enables the successful demonstration of ultrashort pulsed lasers. Various experiments were conducted in both anomalous and normal dispersion regimes to explore the potential of different SMS structures for both bright and dark pulse generation. Within the net anomalous dispersion regime, utilizing step-index multimode fibers (SIMMF) with lengths of 96 mm, 156 mm, and 196 mm in the SMS structures, Q-switched fiber lasers were successfully observed. Remarkably, a notable milestone has been achieved with the observation of the shortest pulse width at 2.4 μs, coupled with a repetition rate of 155.8 kHz, attained at an input power of 343 mW and a center wavelength of 1530 nm. The artificial SA exhibited a significantly elevated damage threshold compared to conventional thin film types. The mode-locked EDFLs were also realized using the grade-index multimode fiber (GIMMF) based SMS structures, with lengths approximately at 45 mm, 100 mm, and
150 mm. These lasers produced both conventional soliton and bound soliton phenomena with pulse widths as low as 290 fs, accompanied by a repetition rate around 22 MHz and a center wavelength of around 1574 nm. Notably, the pulse width exhibited minimal variation across different lengths of GIMMF. Additionally, dark pulses were also realized with a minimum pulse width of 1.6 ns and a repetition rate of 21.5 MHz. Noteworthy spectral analysis revealed the dark pulse to be dual wavelength, with peak wavelengths centered at 1567.2 nm and 1569.4 nm, indicating the presence of a domainwall dark pulse phenomenon By integrating 230 meters of dispersion compensation fiber (DCF) into the cavity, the laser is ensured to operate within a significantly large net normal dispersion region. In this study, a 103 mm length GIMMF-based SMS structure is focused on within this domain. As the pump power increased, multiple pulsing emerged, with the pulse cluster ranging from 3 to 16 pulses. These multiple pulsing instances exhibited remarkably broad dissipative solitons, highlighting the potential of the SMS structure for direct supercontinuum generation. Additionally, harmonic pulses were also observed extending up to the 35th harmonic alongside the dissipative soliton
Evaluating satisfaction, effectiveness, and emerging trends in music teacher education: Insights from pre-service teachers, in-service teachers, and university administrators in the Beijing-Tianjin-Hebei Region / Fang Lin
No full textAs the significance of music education is being increasingly recognized, more and more researchers and practitioners are developing themselves professionally by studying music education in various forms. In today’s China, new contradictions and challenges have emerged in this period of art education reform. A summary of existing research indicates that there are still problems in the development of pre-service music teacher education: curriculum, theory and practice, integration of music disciplines and cooperation between schools. However, there is a shortage of empirical research on preservice music teacher education in China. This thesis investigates challenges of preservice music teacher education in China’s Beijing-Tianjin-Hebei region by exploring how to better connect university preparation and music graduates with actual classroom teaching and society’s needs. This study employed convergent mixed methods research design featuring a questionnaire for 421 pre-service teachers on curriculum satisfaction and interviews with 15 in-service teachers and three university administrators. The findings indicate that pre-service music teachers have a moderate level of satisfaction with curriculum content and design and value music courses over theoretical education courses. In-service music teachers believe that practical music skills training was valuable coursework but that pedagogy was not practical. Enhancing teaching practices, establishing clear goals and standards and encouraging reflective thinking could improve program effectiveness. Administrators advocated the application of educational technologies, praxis thinking and collaboration between universities and local schools to address need to develop key competencies. Several issues were found: 1) the conventional teaching styles of university lecturers; 2) a lack of connection between music education disciplines; 3) insufficient collaboration between universities, society and schools; 4) the curriculum is lagging behind basic education reform; 5) there are not enough practice mentors; and 6) pre-service music teachers are unclear about teacher education goals and standards. Recommendations centre on increasing university-school partnerships for more practical experiences, balancing musical and pedagogical components, training professional mentor teams for teaching practice and placing preservice music teacher education into an experiential continuum to prepare future generations of music teachers
Exploring collaborative pianist’s perceptions on benefits of acquiring conducting skills in Guangdong, China / Xu Ertong
No full textThis study explores collaborative pianists’ perceptions of the benefits of acquiring conducting skills, focusing on three areas: auditory discrimination, orchestration, and interpersonal skills. Grounded in a conceptual framework that integrates theories of skill transfer and professional development in music, it examines how conducting training enhances technical, analytical, and social competencies in collaborative pianists. This study employs qualitative methods, combining thematic analysis of semi-structured interviews with professional pianists and content analysis of relevant literature. The findings reveal that auditory discrimination, enhanced through conducting training, helps pianists address complex musical issues such as intonation, balance, and timbre. Orchestration skills, rooted in advanced musical analysis, were found to enrich pianists’ artistic interpretation and decision-making in ensemble settings. Additionally, the study highlights the importance of interpersonal skills, such as leadership, teamwork, and empathy, which conducting training fosters and which are crucial for effective collaboration. This research highlights the interdisciplinary value of conducting skills in collaborative piano practice and their potential to foster professional development
The effect of using cubase software in a songwriting course on musical creativity of pre-service music teachers in Chongqing, China / Wang Zhucheng
No full textResearchers and educational authorities in several nations have concentrated on incorporating digital music technology into music curriculum to enhance musical creativity. This research sought to investigate the influence of using Cubase software in a songwriting course on the musical creativity of pre-service music teachers in Chongqing, China. The study focused on evaluating the impact on musical originality and musical syntax. An experimental design using a non-equivalent group pre-test and post-test was implemented. The experimental group (n = 31) received instruction in a songwriting course using Cubase software, whilst the control group (n = 30) was instructed by traditional methods. The researcher used the MCTM-II (Measure of Creative Thinking in Music II) scale to assess the musical originality and syntax of two groups of pre-service music teachers before to and during the intervention. The gathered data was evaluated using descriptive statistics and independent samples t-tests to identify any differences between the two groups for musical originality and musical syntax. The study findings indicate that using Cubase software in a songwriting course can effectively enhance the musical originality and musical syntax of pre-service music teachers. Cubase software's comprehensive functionalities enable students to delve into intricate structural components and enhance their songwriting skills, thereby facilitating the development of musical syntax. Moreover, Cubase promotes originality by offering a flexible platform for exploring a wide range of sounds, styles, and creative methods. The software's prompt feedback and iterative features enhance the creation of innovative ideas, leading to the creation of other creative works of music. This study demonstrates the effectiveness of Cubase software in enhancing musical creativity based on empirical research. It also supplies data to facilitate future research on the long-term impacts of incorporating this technology into music education methodologies and musical creativity
Development of adsorbents from natural resources for the removal and determination of mercury in water samples / Nur Faizah Mohd Jailani
No full textThis study explores the potential of turmeric powder and eggshell membrane as natural adsorbents
for the removal of Hg(II) in water. Turmeric powder was modified using carbon disulfide and
incorporated with silica gel via a sol-gel process to enhance its adsorption performance, yielding an
adsorbent called SiO2-MT. Whereas, the eggshell membrane (ESM) was used in its natural form due
to its intrinsic fibrous structure and functional groups. Adsorbents were characterized by FTIR, EDX,
FESEM, TGA, and BET, to assess their adsorption study, and the concentration of Hg(II) was
measured using cold vapor atomic absorption spectroscopy (CV-AAS). In the removal study of Hg(II)
in water, the effect of pH solution, adsorbent dosage, and contact time on adsorption efficiency was
studied, along with evaluations of isotherm and kinetic models. ESM showed superior adsorption
capacity (153.85 mg/g) compared to SiO2-MT (37.6 mg/g). Therefore, ESM was selected for further
study on the determination of Hg(II) using an innovative in-syringe membrane solid-phase extraction
(ISMSPE) technique, which offers significant advantages over traditional SPE methods. To enhance
the ISMSPE technique, parameters such as eluent type and concentration, adsorption-desorption
cycles, and eluent and sample volumes were optimized. This optimization resulted in a method with
a limit of detection (LOD) of 0.44 μg/L, a limit of quantification (LOQ) of 1.32 μg/L, and recovery
rates of 89.3–99.7%, with relative standard deviations (RSD) ranging from 1.0% - 8.0% for real water
samples. These results confirm the effectiveness of ESM as a sustainable, high-performance sorbent
for the removal and determination of Hg(II) in water, providing a greener and more effective approach
to water treatment and environmental monitoring
Integrating learning management techniques, challenges and strategies towards a decision-making model for hybrid learning among academic leaders and lecturers in Chengdu universities / Wang Zhenlin
No full textThis study examines the rapid shift to hybrid learning, which combines traditional and online education, due to the COVID-19 pandemic. It specifically focuses on Chengdu's institutions to investigate the adjustments made by academic leaders and lecturers. In the midst of a worldwide health crisis that has greatly affected educational methods, this study examines the specific circumstances in Chengdu through case studies. It focuses on the city's universities, which are leading the way in implementing hybrid learning solutions. The abrupt transition to hybrid modalities has brought out numerous challenges, ranging from technological obstacles to pedagogical adjustments, necessitating a thorough examination to identify and address these issues. This study utilizes a qualitative multiple case study approach to examine classroom management practices, identify challenges faced, analyze strategies implemented, and develop a decision-making model that promotes support. It collaborates with a diverse range of academic leaders and lecturers from three prominent universities in Sichuan. As findings, the study uncovers significant challenges, such as the incorporation of technology and changes in teaching methods, using semi-open-ended interviews. These challenges are analyzed thematically using ATLAS.ti software. Additionally, the study reveals successful strategies developed by educational professionals to overcome these obstacles. The findings highlight the important relationship between the acceptability of technology, educational innovation, and support systems, emphasizing the immediate need for comprehensive measures to improve hybrid learning outcomes. This research contributes to the academic discussion on hybrid education and provides practical insights for teaching methods, policy development, and institutional planning. It emphasizes the need for a comprehensive decision-making model to help educators in Chengdu's higher education institutions improve the hybrid learning environment