Arima and integrated Arfima models for forecasting annual demersal and pelagic marine fish production in Malaysia

The seas surrounding Malaysia provide a rich source of marine fisheries. The fisheries industry is an important economic earner and the total marine fish production has increased drastically from 242,900 metric tonnes in 1970 to around a million metric tonnes in the year 2000. Since fisheries resources are renewable, proper management issues should be taken to manage these fisheries resources. From the management point of view, fish forecasting is a very important tool for fisheries managers and scientists to enable them to decide on sustainable management issues. Time series models have been used to forecast various phenomena in many fields. In a previous research by Mahendran Shitan et. al. (2004), the maximum likelihood and bootstrap method were used to forecast the total Malaysian marine fish production. Marine fish can be sub-classified as demersal marine fish and pelagic marine fish and it would be interesting to forecast the individual composition of these categories. Therefore, in this research we fit time series models to forecast the demersal and pelagic marine fish production using ARIMA and integrated ARFIMA models and make predictions of each category. Our results indicate that the ARIMA models appear to be the better models and the forecasted amounts for the year 2011 are approximately 373,370 and 666,460 metric tonnes for the demersal and pelagic marine fish, respectively

Fabrication of highly ordered TiO2 Nanotubes from Fluoride containing Aqueous Electrolyte by Anodic Oxidation and their Photoelectrochemical response.

The fabrication of TiO2 nanotubes (TNT) was carried out by electrochemical anodization of Ti in aqueous electrolyte containing NH4F. The effect of electrolyte pH, applied voltage, fluoride concentration and anodization duration on the formation of TNT was investigated. It was observed that self-organized TNT can be formed by adjusting the electrolyte to pH 2-4 whereby applied voltage of 10-20 V can be performed to produce highly ordered, well-organized TNT. At 20 V, TNT can be fabricated in the concentration range of 0.07 M to 0.20 M NH4F. Higher fluoride concentration leads to etching of Ti surface and reveals the Ti grain boundaries. The prepared TNT films also show an increase in depth and in size with time and the growth of TNT films reach a steady state after 120 minutes. The morphology and geometrical aspect of the TNT would be an important factor influencing the photoelectrochemical response, with higher photocurrent response is generally associated with thicker layer of TNT. Consequently, one can tailor the resulting TNT to desired surface morphologies by simply manipulating the electrochemical parameters for wide applications such as solar energy conversion and photoelectrocatalysis

Dietetics Students' Perceived Facilitators and Barriers to Clinical Training in Malaysia: A Qualitative Theory-Guided Analysis

This study explored barriers and facilitators experienced by Malaysian dietetics graduates during clinical training in local healthcare settings. A qualitative study with phenomenological design was conducted on fifteen purposely selected fresh dietetics graduates, with a mean age of 24.7±0.8 years from seven local universities. Virtual interviews were conducted via the Cisco Webex and were verbatim transcribed and thematically analyzed using NVivo 12 Plus software. Data collection continued until data saturation was reached. Nine Theoretical Domain Frameworks (TDF-derived domains), comprising of 1) knowledge, 2) skills; 3) belief about capabilities; 4) intention; 5) goals; 6) memory, attention, and decision process; 7) environmental context and resources; 8) social influences; and 9) emotions domains, was utilized to develop open-ended questions in the semi-structured questionnaire. Within these domains, frequently associated sub-themes of perceived facilitators were identified: early preparation and comprehension. Pre-clinical classes that involve solving diverse and challenging cases equip students with practical understanding of clinical training. Curriculum-based university clinics offer valuable insights into hospital dietetics practice. Resources availability is crucial for effective Nutrition Care Process (NCP) implementation and aids in evidence-based nutrition counseling. Conversely, the factor that hinders clinical training reported by dietetics graduates is a lack of knowledge and readiness, particularly concerning their perceived knowledge before clinical training. Dissatisfaction also arises from challenges in building rapport, gathering patient information during counseling, and difficulties in assessing dietary recall with patients from diverse cultural backgrounds, affecting their readiness for dietetics practice and therefore, highlighting the need to enhance multicultural knowledge and cultural competency training among dietetics students. The findings from this study may assist in developing strategies to promote impactful experiences and enhance dietetic students' preparedness for clinical practice

Preparation and characterization of nanostructured TiO2 via electrochemical anodization in aqueous ammonium fluoride

Electrochemical anodization of titanium (Ti) in acidic fluorinated electrolyte has emerged as a simple and straightforward method to synthesize TiO2 coating on Ti substrates directly. In this study, attempt was made to perform the anodic oxidation of Ti foil in a standard two-electrode bath containing relatively mild electrolyte, NH4F at various potentials for 1 hour. The resulting TiO2 films were characterized with X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM) and linear sweep photovoltammetry. XRD analysis revealed the amorphous nature of the as-anodized samples which crystallize after calcination in open air atmosphere at 500 oC for 2 hours. TiO2 films synthesized via anodization on polished Ti substrate demonstrated pure anatase phase only whereas anodization of etched Ti foil with HNO3 showed a mixture of anatase and rutile phase. Different morphologies of TiO2 could be obtained depending on the applied voltage used. Both as-anodized and calcined TiO2 films showed photocurrent response when illuminated from 300 W halogen lamp with that synthesized via anodization of etched Ti foil exhibited relatively higher photocurrent than the other samples, demonstrating the important of surface treatment of Ti on the photoelectrochemical response of TiO2 film

The effect of heat treatment on phase transformation, morphology and photoelectrochemical response of short TiO2 nanotubes.

TiO2 nanotubes (TNT) have attracted considerable attention due to large specific surface area in a small geoetrical area and fewer interfacial grain boundaries. However, thermal stability and crystalline phase of TNT greatly affects their potential applications in the areas of photocatalysis, optoelectronics and gas sensing. Thus, thermal stability and phase transition of highly ordered TNT via calcination from 200-800 oC were studied in open air atmosphere. The results indicated that the as-anodized TNT is amorphous and transformed to anatase phase at 300 oC. Crystallization of anatase phase increases on elevating calcination temperature and rutile phase co-existed at 500 oC. No discernable changes in the nanotubes dimensions were found and TNT is thermally stable up to temperature lower than 600 oC, above which significant sintering of TNT occurred. At 800 oC, grain growth and oxidation of Ti resulted in completely collapsed of TNT to dense rutile crystallites. Photoelectrochemical response of calcined TNT enhanced substantially with respect to that of as-anodized samples and gradually increased with elevating temperature up to 500 oC after which they decreased, which was probably ascribed to changes in phase structural and morphological properties of TNT

Structural Characterization and Visible Light-Induced Photoelectrochemical Performance of Fe-Sensitized TiO2 Nanotube Arrays Prepared via Electrodeposition

Surface modification of TiO2 nanotube arrays via metal doping is one of the approaches to narrow the wide bandgap of TiO2 in order to increase its adsorption to the visible region. The present work focuses on the fabrication of a Fe-sensitized TiO2 nanotube arrays (Fe- TNT) photoanode. Ordered Fe-TNTs were successfully synthesized using a facile two-step electrochemical method by varying the deposition voltage (2-4 V). The morphology, structure, composition, and visible light response were characterized by field-emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), UV-Vis diffusion reflection spectroscopy (DRS), and photoelectrochemical (PEC) test. The XRD investigation demonstrated that the sensitization of Fe did not destroy the nanotube array structure, and the Fe-TNTs had an anatase phase composed of cubic-like particles at higher deposition voltages. The UV–Vis absorption spectra of the Fe-TNTs showed a redshift of photoresponse towards visible light. Such a redshift was characterized by a decrease in bandgap energy and the photo efficiency was enhanced. The optimal photoelectrochemical performance was observed at 2.5 V deposition voltage for 10 minutes and surpassed that of pristine titania nanotube arrays. The present work demonstrates feasible modification of TiO2 with Fe as a potential photoanode in solar conversion devices

Facile synthesis and characterization of a visible light‑active ternary TiO2/ZnS/g‑C3N4 heterostructure for multipollutant degradation

This study revolves around assessing the effectiveness of a ternary heterostructure,TiO2/ZnS/g-C3N4 (1:1:1 w/w mixture), synthesized through a facile hydrothermal process for the simultaneous degradation of both single and mixed pollutants under visible light. The advanced microscopic and spectroscopic techniques(FESEM, TEM, FTIR, UVDRS, BET) employed confirmed its enhanced photocatalytic performance. The UV–Vis DRS analysis unveiled the synthesized heterostructure’s superior band gap energy of 2.81 eV compared to pristine TiO2, leading to enhanced light absorption within the visible spectrum. Under visible light exposure, the ternary TiO2/ ZnS/g-C3N4 heterostructure exhibited impressive efficacy, removing approximately 90% of 10 mg/L of Rhodamine B (RhB) within 180 min. Furthermore, its remarkable performance extended to mixed pollutants, wherein it concurrently achieved substantial degradation of 82.7%, 78.2%, and 62.2% for RhB, methyl orange (MO), and 2-chlorophenol (2CP), respectively, in a comparable timeframe. Notably, only a marginal reduction from 89.9 to 86.6% was observed in RhB degradation after four recycling cycles, attesting to the inherent stability and recycling potential of the ternary structure. The synthesis and application of the ternary TiO2/ ZnS/g-C3N4 heterostructure highlight its significant potential for practical wastewater treatment, particularly due to its dual capability of effectively degrading both single and mixed pollutants. The study’s findings highlight the promising role of this heterostructure in addressing contemporary challenges in environmental remediation

Combined effects of adsorption and photocatalysis by hybrid TiO<inf>2</inf>/ZnO-calcium alginate beads for the removal of copper

The use of nanosized titanium dioxide (TiO2) and zinc oxide (ZnO) in the suspension form during treatment makes the recovering and recycling of photocatalysts difficult. Hence, supported photocatalysts are preferred for practical water treatment applications. This study was conducted to investigate the efficiency of calcium alginate (CaAlg) beads that were immobilized with hybrid photocatalysts, TiO2/ZnO to form TiO2/ZnO–CaAlg. These immobilized beads, with three different mass ratios of TiO2:ZnO (1:1, 1:2, and 2:1) were used to remove Cu(II) in aqueous solutions in the presence of ultraviolet light. These beads were subjected to three cycles of photocatalytic treatment with different initial Cu(II) concentrations (10–80 ppm). EDX spectra have confirmed the inclusion of Ti and Zn on the surface of the CaAlg beads. Meanwhile, the surface morphology of the beads as determined using SEM, has indicated differences of before and after the photocatalytic treatment of Cu(II). Among all three, the equivalent mass ratio TiO2/ZnO–CaAlg beads have shown the best performance in removing Cu(II) during all three recycling experiments. Those TiO2/ZnO–CaAlg beads have also shown consistent removal of Cu, ranging from 7.14–62.0 ppm (first cycle) for initial concentrations of 10–80 ppm. In comparison, bare CaAlg was only able to remove 6.9–48 ppm of similar initial Cu concentrations. Thus, the potential use of TiO2/ZnO–CaAlg beads as environmentally friendly composite material can be further extended for heavy metal removal from contaminated water

Monotone Data Samples Do Not Always Generate Monotone Fuzzy If-Then Rules

The Wang–Mendel (WM) method is one of the earliest methods to learn fuzzy If-Then rules from data. In this article, the WM method is used to generate fuzzy If-Then rules for a zero-order Takagi–Sugeno–Kang (TSK) fuzzy inference system (FIS) from a set of multi-attribute monotone data. Convex and normal trapezoid fuzzy sets are used as fuzzy membership functions. Besides that, a strong fuzzy partition strategy is used. Our empirical analysis shows that a set of multi-attribute monotone data may lead to non-monotone fuzzy If-Then rules. The same observation can be made, empirically, using adaptive neuro-fuzzy inference system (ANFIS), a well-known and popular FIS model with neural learning capability. This finding is important for the modeling of a monotone FIS model, because it shows that even with a “clean” data set pertaining to a monotone system, the generated fuzzy If-Then rules may need to be preprocessed, before being used for FIS modeling. In short, it is imperative to develop methods for preprocessing non-monotone fuzzy rules from data, e.g., monotone fuzzy rules relabeling, or removing non-monotone fuzzy rules, is important (and is potentially necessary) during the course of developing data-driven FIS models

TiO2/PKSAC functionalized with Fe3O4 for efficient concurrent removal of heavy metal ions from water

An effective material to assist in the elimination of heavy metal contaminants in the water system is necessary, as they persist for a long period in the environment. A novel multifarious TiO2/PKSAC/Fe3O4 composite with combined properties namely adsorption, photocatalytic and magnetic was successfully synthesized and applied for the simultaneous removal of mixed heavy metals, Pb(II), Cu(II), and Ni(II) under various conditions. Characterizations confirmed the fabrication of TiO2/PKSAC/Fe3O4 composite. An optimal adsorbent dosage of 0.9 g/L allowed >80% removal efficiency in 10 ppm of mixed metal ions solution. Among all three catalyst ratios, the equivalent mass ratio of 1:1:1 (TiO2/PKSAC/Fe3O4) demonstrated the best performance (>72%) in removing Pb(II), Cu(II), and Ni(II) ions, even after the addition of coexisting ions (Ca2+, Na+, Cl−, Br−) during the treatment. A recycling study confirmed the materials' regenerative stability. The fabricated TiO2/PKSAC/Fe3O4 composite can be applied as an effective material for heavy metals removal in wastewater