Values Of Parameters Research Articles

Design and Modelling of Urban Stormwater Management and Treatment Infrastructure for Communities in Wuse, Abuja

Effective stormwater management can be used to regulate water quantity and quality for environmental sustainability, flood control, pollution reduction and other advantages of civil engineering infrastructures. Pollution of the environment and contamination of water sources can emanate from improper stormwater management. This study used a small-scale model of rainwater harvesting to analyze the design and model of urban stormwater management and treatment infrastructure for the neighborhoods in Abuja. The water quality of the treated stormwater retrieved has improved as a result of the usage of memory foam, alum, and chlorine to filter out contaminants and pathogens. With the fictitious stormwater treatment model created for this study, average values of the physicochemical parameters were collected from the stormwater discharge after it had been filtered and treated. The use of potash alum has had a variety of effects on the water’s quality. From 697 mg.L-1 to 635 mg.L-1, the total dissolved solids dropped. The DO dropped from 5.87 mg.L-1 to 3.92 mg.L-1 as well. Additionally, the turbidity rose from 4.42 FNU to 4.58 FNU, and the salinity rose from 0.7 PSU to 1.44 PSU, respectively. pH decreases from 19.78 to 15.17 mg.L-1, BOD decreases from 8.35 to 6.51, and COD decreases from 2.55 to 1.9. Calcium hardness has decreased from 287 mg.L-1 to 265.83 mg.L-1. The conductivity increases marginally from 3.24 ms.cm-1 to 3.82 ms.cm-1. The Fe2+ and Zn2+ ions exhibit a little decrease from 0.143 mg.L-1 to 0.055 mg.L-1 and from 0.092 mg.L-1 to 0.045 mg.L-1, respectively. Due to inadequate or nonexistent drainage systems in the many states and villages throughout the country, stormwater run-off management and treatment in Nigeria have been a colossal failure. Effective stormwater management can be sustained by using legal and environmental laws.

Proving chaos for a system of coupled logistic maps: A topological approach.

In the work, we prove the presence of chaotic dynamics, for suitable values of the model parameters, for the discrete-time system, composed of two coupled logistic maps, as formulated in Yousefi et al. [Discrete Dyn. Nat. Soc. 5, 161-177 (2000)], which describes two interdependent economies, characterized by two competitive markets each, with a demand link between them. In particular, we rely on the SAP (Stretching Along the Paths) method, based on a stretching relation for maps defined on sets homeomorphic to the unit square and expanding the paths along one direction. Such technique is topological in nature and allows to establish the existence of a semiconjugacy between the considered dynamical system and the Bernoulli shift, so that the main features related to the chaos of the latter (e.g., the positivity of the topological entropy) are transmitted to the former. In more detail, we apply the SAP method both to the first and to the second iterate of the map associated with our system, and we show how dealing with the second iterate, although being more demanding in terms of computations, allows for a larger freedom in the sign and in the variation range of the linking parameters for which chaos emerges. Moreover, the latter choice guarantees a good agreement with the numerical simulations, which highlight the presence of a chaotic attractor under the conditions derived for the applicability of the SAP technique to the second iterate of the map.

Prognosis of mechanically ventilated patients with COVID-19 after failure of high-flow nasal cannula: a retrospective cohort study

BackgroundThere is an argument whether the delayed intubation aggravate the respiratory failure in Acute respiratory distress syndrome (ARDS) patients with coronavirus disease 2019 (COVID-19). We aimed to investigate the effect of high-flow nasal cannula (HFNC) failure before mechanical ventilation on clinical outcomes in mechanically ventilated patients with COVID-19.MethodsThis retrospective cohort study included mechanically ventilated patients who were diagnosed with COVID-19 and admitted to the intensive care unit (ICU) between February 2020 and December 2021 at Asan Medical Center. The patients were divided into HFNC failure (HFNC-F) and mechanical ventilation (MV) groups according to the use of HFNC before MV. The primary outcome of this study was to compare the worst values of ventilator parameters from day 1 to day 3 after mechanical ventilation between the two groups.ResultsOverall, 158 mechanically ventilated patients with COVID-19 were included in this study: 107 patients (67.7%) in the HFNC-F group and 51 (32.3%) in the MV group. The two groups had similar profiles of ventilator parameter from day 1 to day 3 after mechanical ventilation, except of dynamic compliance on day 3 (28.38 mL/cmH2O in MV vs. 30.67 mL/H2O in HFNC-F, p = 0.032). In addition, the HFNC-F group (5.6%) had a lower rate of ECMO at 28 days than the MV group (17.6%), even after adjustment (adjusted hazard ratio, 0.30; 95% confidence interval, 0.11–0.83; p = 0.045).ConclusionsAmong mechanically ventilated COVID-19 patients, HFNC failure before mechanical ventilation was not associated with deterioration of respiratory failure.

Chemical differences among collapsing low-mass protostellar cores

Context. Organic features lead to two distinct types of Class 0/I low-mass protostars: hot corino sources exhibiting abundant saturated complex organic molecules (COMs) and warm carbon-chain chemistry (WCCC) sources exhibiting abundant unsaturated carbon-chain molecules. Some observations suggest that the chemical variations between WCCC sources and hot corino sources are associated with local environments and the luminosity of protostars. Aims. We aim to investigate the physical conditions that significantly affect WCCC and hot corino chemistry, as well as to reproduce the chemical characteristics of prototypical WCCC sources and hybrid sources, where both carbon-chain molecules and COMs are abundant. Methods. We conducted a gas-grain chemical simulation in collapsing protostellar cores, adopting a selection of typical physical parameters for the fiducial model. By adjusting the values of certain physical parameters, such as the visual extinction of ambient clouds (AVamb), cosmic-ray ionization rate (ζ), maximum temperature during the warm-up phase (Tmax), and contraction timescale of protostars (tcont), we studied the dependence of WCCC and hot corino chemistry on these physical parameters. Subsequently, we ran a model with different physical parameters to reproduce scarce COMs in prototypical WCCC sources. Results. The fiducial model predicts abundant carbon-chain molecules and COMs. It also reproduces WCCC and hot corino chemistry in the hybrid source L483. This suggests that WCCC and hot corino chemistry can coexist in some hybrid sources. Ultraviolet (UV) photons and cosmic rays can boost WCCC features by accelerating the dissociation of CO and CH4 molecules. On the other hand, UV photons can weaken the hot corino chemistry by photodissociation reactions, while the dependence of hot corino chemistry on cosmic rays is relatively complex. The value of Tmax does not affect any WCCC features, while it can influence hot corino chemistry by changing the effective duration of two-body surface reactions for most COMs. The long tcont can boost WCCC and hot corino chemistry by prolonging the effective duration of WCCC reactions in the gas phase and surface formation reactions for COMs, respectively. The scarcity of COMs in prototypical WCCC sources can be explained by insufficient dust temperatures in the inner envelopes that are typically required to activate hot corino chemistry. Meanwhile, the high ζ and the long tcont favors the explanation for scarce COMs in these sources. Conclusions. The chemical differences between WCCC sources and hot corino sources can be attributed to the variations in local environments, such as AVamb and ζ, as well as the protostellar property, tcont.

Hydrophobic effects on a solid sphere translating in a Brinkman couple stress fluid covered by a concentric spherical cavity

In this study, a fluid flow with an incompressible axisymmetric steady couple stress translated through a porous media is analyzed between a hollow sphere and a concentric rigid sphere. In the permeable region, the flow field is regulated by Brinkman's equation. The slip and spin slip conditions are applied on both the rigid sphere and spherical cavity surfaces. Modified Bessel functions provide a systematic approach to the problem by utilizing the principle of a stream function. On the inner sphere, the wall correction factor that an incompressible couple stress fluid encounters is calculated. The effects of the slip, spin slip, coupling stress parameter, separation distance, and permeability parameter on the field functions and the normalized drag force are also graphically shown. The corresponding results are contrasted with the outcomes reported for particular cases of couple stress fluid and viscous fluid flow in two permeability-free concentric circles. Furthermore, graphs of the streamlines for various values of the relevant parameters have been included.

Effects of Hugoniot properties on jet onset conditions

Jets are the earliest ejected material from a hypervelocity impact event. Jets comprises of projectile and target's surface material and are ejected at velocities higher than escape velocity for Earth. Effects of Hugoniot properties of the projectile and target material on jet initiation are not well understood. We, therefore, developed a mathematical model that incorporated the limitations imposed by Hugoniot properties on jet initiation for hypervelocity impact. This model analysed the effects of changes in Hugoniot properties of the projectile and target on the jet onset time, jet onset velocity and jetting side (projectile or target). The results reveal that (i) jet initiates earlier and at higher velocity if the jetting side has higher value of shock parameter or higher velocity of sound in the material; (ii) jet initiates later and at lower velocity if jetting side has high density; (iii) effect of s-parameter and speed of sound in material is more profound than the effect of density.

Proximate analysis, levels of trace heavy metals and associated human health risk assessments of Ethiopian white sugars

In this study, white sugar samples collected from five Ethiopian sugar manufacturing plants were analyzed for their proximate composition, and trace heavy metals level (Fe, Co, Ni, Mn, Zn, Cr, Cd, and Pb). Human health risk assessments associated with heavy metals exposure from white sugar ingestion were also assessed. Proximate analysis was conducted according to AOAC methods. For heavy metals determination, the sugar samples were digested using a mixture of HNO3, HClO4 and H2O2 (4:3:1) at 250 °C for 3 h prior to FAAS analysis. The measured mean values (%) of proximate parameters including moisture, ash, fiber, protein, fat and carbohydrate were found in the range of 0.07–0.61, 2.56–4.33, 0.06–0.24, 0.78–1.49, 1.16–1.89 and 92.13–95.03, respectively. The average concentration of heavy metals found in the sugar samples were ranged as 1.366–12.502, 0.107–0.268, 0.099–0.842, 0.458–1.000, 10.140–25.480, 0.053–0.322, 0.427–0.827 and 0.074–0.528 in mg/kg for Fe, Mn, Ni, Co, Zn, Cr, Cd and Pb, respectively. All the studied metals are below FAO/WHO permissible limit except Cd and Pb in Kessem, Fincha'a and Metahara samples. The target hazard quotient (THQ) and hazard index (HI) values are <1, indicating no non-carcinogenic risks of the heavy metals to an adult population via consumption of white sugar. However, the single element incremental lifetime cancer risk (ILCR) occurrence is probable from Ni for samples obtained from Kessem sugar factory (ILCR>1.0 × 10−4). The cumulative ILCR of heavy metals (Ni, Cr, Cd and Pb) resulting from consumption of white sugar by an adult person reveal a potential adverse cancer risk (ILCR>1.0 × 10−4) for all the studied samples except for sugar samples obtained from Wonji sugar factory. Therefore, continuous monitoring of these toxic metals should be made mainly by sugar industries and responsible government regulatory bodies to avert heavy metal toxicity associated with white sugar consumption in Ethiopia.

The prevalence of fibromyalgia in adults at Al-Karak Jordan: a cross-sectional study.

Fibromyalgia is a chronic and intricate musculoskeletal disorder characterized by widespread pain, fatigue, and tenderness in specific anatomical regions. Although its prevalence varies among populations, understanding the prevalence in different geographical areas is crucial for healthcare planning. This cross-sectional study aims to determine the prevalence of fibromyalgia in adults residing in Al-Karak, Jordan. The city's unique demographic and environmental characteristics may influence the occurrence of fibromyalgia among its adult population. The study aims to address gaps in knowledge, provide localized insights, and shed light on fibromyalgia's burden on the community's health. Accurate prevalence data aids healthcare planning and resource allocation. This research collected data from 965 social media participants using Google Forms. The American College of Rheumatology survey criteria for diagnosing fibromyalgia were used. To investigate the predictive value of various parameters, univariate and multivariate logistic regression analyses were performed. The study found a 26.5% prevalence of fibromyalgia in the studied population. Female gender, mental health illnesses, and comorbidities like irritable bowel syndrome, psychiatric disorders, and rheumatological and neurological diseases were significantly associated with fibromyalgia. Age, BMI, marital status, employment status, and certain comorbidities did not show statistically significant predictive value. This study sheds light on fibromyalgia's prevalence and associated factors in the Al-Karak population. The identified predictors highlight the necessity for comprehensive healthcare strategies and interventions to mitigate the disease burden. These findings aid policymakers and healthcare professionals in planning and implementing effective measures for fibromyalgia management and prevention. Further research is warranted to deepen our understanding of fibromyalgia's complexity and its implications in this region.

The role of baseline 2-[18 F]-FDG-PET/CT metrics and radiomics features in predicting primary gastric lymphoma diagnosis.

Diffuse Large B-Cell Lymphomas (DLCBL) and mucosa-associated lymphoid tissue (MALT) are the two most common primary gastric lymphomas (PGLs), but have strongly different features. DLBCL is more aggressive, is frequently diagnosed at an advanced stage and has a poorer prognosis. The aim of this retrospective study was to explore the role of fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (2-[18 F]-FDG-PET/CT) and radiomics features (RFs) in predicting the final diagnosis of patients with PGLs. Ninety-one patients with newly diagnosed PGLs who underwent pre-treatment 2-[18 F]-FDG-PET/CT were included. PET images were qualitatively and semi-quantitatively analyzed by deriving maximum standardized uptake value body weight (SUVbw), maximum standardized uptake value lean body mass (SUVlbm), maximum standardized uptake value body surface area (SUVbsa), lesion to liver SUVmax ratio (L-L SUV R), lesion to blood-pool SUVmax ratio (L-BP SUV R), metabolic tumor volume (gMTV) and total lesion glycolysis of gastric lesion (gTLG), total MTV (tMTV), TLG, and first-order RFs (histogram-related and shape related). Receiver-operating characteristic (ROC) curve analyses were performed to determine the differential diagnostic values of PET parameters. The final diagnosis was DLBCL in 54 (59%) cases and MALT in 37 cases (41%). PGLs showed FDG avidity in 83 cases (90%), 54/54 of DLBCL and 29/37 of MALT. All PET/CT metabolic features, such as stage of disease and tumor size, were significantly higher in DLBCL than MALT; while the presence of H. Pylori infection was more common in MALT. At univariate analysis, all PET/CT metrics were significantly higher in DLBCL than MALT lymphomas, while among RFs only Shape volume_vx and Shape sphericity showed a significant difference between the two groups. In conclusion we demonstrated that 2-[18 F]-FDG-PET/CT parameters can potentially discriminate between DLBCL and MALT lymphomas with high accuracy. Among first-order RFs, only Shape volume_vx and Shape sphericity helped in the differential diagnosis.

Analytic structure of the associated Legendre functions of the second kind

We consider the complex ν plane structure of the associated Legendre functions of the second kind Qν−1/2−K(cosh⁡ρ). We find that for any noninteger value of K the Qν−1/2−K(cosh⁡ρ) have an infinite number of poles in the complex ν plane, but for any negative integer K there are no poles at all. For K = 0 or any positive integer K there is only a finite number of poles, with there only being one single pole (at ν = 0) when K = 0. This pattern is analogous to the pattern of exceptional points that appear in a wide variety of physical contexts. However, while theories with exceptional points usually lose a finite number of degrees of freedom at the exceptional points, the Qν−1/2−K(cosh⁡ρ) lose an infinite number of poles whenever K is integer. Moreover, while theories with exceptional points usually have a finite number of such exceptional points, the Qν−1/2−K(cosh⁡ρ) possess an infinite number of points (all integer K) at which they lose degrees of freedom. Other than in the PT-symmetry Jordan-block case, exceptional points usually occur at complex values of parameters. While not being Jordan-block exceptional points themselves, the poles associated with the Qν−1/2−K(cosh⁡ρ) nonetheless occur at real values of K.

Influence of yeast size on the kinetics of cell disruption in an ultrasonic homogenizer

The results of studies on the disintegration kinetics of the yeast Saccharomyces cerevisiae are presented. The process was carried out in a 500 W ultrasonic homogenizer equipped with a spherical working chamber with a volume of 100 cm 3. The concentration of the suspension of microorganisms was 0.05 g d.m./cm 3. The continuous phase was water solution containing 0.15 M NaCl and 4 mM K 2HPO 4. The kinetics of cell disruption were studied by the direct method. The theory of random transformation of dispersed matter was used to analyze the process. There was significant variation in the size of yeast cells. The range of changes in the values of parameters describing the size of microorganisms was divided into size classes. The kinetics of cell disruption in individual classes was described by a first-order linear differential equation. During the implosion of cavitation bubbles, the transformation volume of individual microorganisms is generated. It has been shown that as the volume of cells in subsequent size classes increases, their transformation volumes do not increase significantly. The safe volume for cells remains unchanged. As the size of the microorganisms increased, there was no increase in the constant rate of cell disruption.

Dynamic evolution control for the DC/DC boost converter design and implementation

This paper introduces the design and hardware implementation of the dynamic evolution control for a DC/DC boost converter. The development of the controller aims to effectively regulate the output voltage of the DC/DC boost converter with a high degree of precision. A comprehensive examination of the duty cycle formula for the boost converter is conducted using a non-linear analysis approach. This study introduces a methodology for the synthesis of a converter controller utilizing the principles of dynamic evolution control theory. The converter's output consistently aligns with the target voltage by following the dynamic evolution path determined by the designed controller. The performance evaluation of the proposed boost converter controller utilizing dynamic evolution control is being validated through the utilization of MATLAB/Simulink simulation software. The effectiveness of the proposed controller is further validated through the presentation of hardware results. The performance of the controller was evaluated by varying the values of parameters k and m.

In Silico Analysis of Natural Plant-Derived Cyclotides with Antifungal Activity against Pathogenic Fungi.

Fungal infections in plants, animals, and humans are widespread across the world. Limited classes of antifungal drugs to treat fungal infections and loss of drug efficacy due to rapidly evolving fungal strains pose a challenge in the agriculture and health sectors. Hence, the search for a new class of antifungal agents is imperative. Cyclotides are cyclic plant peptides with multiple bioactivities, including antifungal activity. They have six conserved cysteine residues forming three disulfide linkages (CI-CIV, CII-CV, CIII-CVI) that establish a Cyclic Cystine Knot (CCK) structure, making them extremely resistant to chemical, enzymatic, and thermal attacks. This in silico analysis of natural, plant-derived cyclotides aimed to assess the parameters that can assist and hasten the process of selecting the cyclotides with potent antifungal activity and prioritize them for in vivo/ in vitro experiments. The objective of this study was to conduct in silico studies to compare the physicochemical parameters, sequence diversity, surface structures, and membrane-cyclotide interactions of experimentally screened (from literature survey) potent (MIC ≤ 20 μM) and non-potent (MIC > 20 μM) cyclotides for antifungal activity. Cyclotide sequences assessed for antifungal activity were retrieved from the database (Cybase). Various online and offline tools were used for sequence-based studies, such as physicochemical parameters, sequence diversity, and neighbor-joining trees. Structure-based studies involving surface structure analysis and membrane-cyclotide interaction were also carried out. All investigations were conducted in silico. Physicochemical parameter values, viz. isoelectric point, net charge, and the number of basic amino acids, were significantly higher in potent cyclotides compared to non-potent cyclotides. The surface structure of potent cyclotides showed a larger hydrophobic patch with a higher number of hydrophobic amino acids. Furthermore, the membrane-cyclotide interaction studies of potent cyclotides revealed lower transfer free energy (ΔG transfer) and higher penetration depth into fungal membranes, indicating higher binding stability and membrane-disruption ability. These in silico studies can be applied for rapidly identifying putatively potent antifungal cyclotides for in vivo and in vitro experiments, which will ultimately be relevant in the agriculture and pharmaceutical sectors.

Bifurcation analysis and exact wave solutions of the nano-ionic currents equation: Via two analytical techniques

In this work, numerous nonlinear evolution equations, namely the nano-ionic current equation, have wide applications in various fields of science and technology. To achieve this, we employ the generalized auxiliary equation and extended hyperbolic function techniques to investigate the exact wave solutions of the model under consideration. We obtained a range of exact wave solutions, including bright, dark, singular-periodic, periodic, and w-shape solutions, for the nonlinear model under examination, as well as rational and exponential function solutions with various structures, which are explored in our manuscript. In this paper, we compared the solutions obtained using the GAE and EHF approaches and also compared the obtained solutions using the GAE scheme with the solutions reported in Aljahdaly et al. [43]. Moreover, the three-dimensional and contour graphs are included to illustrate the structure of some obtained solutions by selecting specific parameter values. Bifurcation analysis is illustrated by phase plane analysis; phase plots are employed to depict the dynamic structure and are also analyzed for the existence of other solutions. These techniques serve as reliable, simple, and potent tools to analyze various nonlinear evolution equations found in physics, applied mathematics, and engineering.

Optimal control of ribosome population for gene expression under periodic nutrient intake.

Translation of proteins is a fundamental part of gene expression that is mediated by ribosomes. As ribosomes significantly contribute to both cellular mass and energy consumption, achieving efficient management of the ribosome population is also crucial to metabolism and growth. Inspired by biological evidence for nutrient-dependent mechanisms that control both ribosome-active degradation and genesis, we introduce a dynamical model of protein production, that includes the dynamics of resources and control over the ribosome population. Under the hypothesis that active degradation and biogenesis are optimal for maximizing and maintaining protein production, we aim to qualitatively reproduce empirical observations of the ribosome population dynamics. Upon formulating the associated optimization problem, we first analytically study the stability and global behaviour of solutions under constant resource input, and characterize the extent of oscillations and convergence rate to a global equilibrium. We further use these results to simplify and solve the problem under a quasi-static approximation. Using biophysical parameter values, we find that optimal control solutions lead to both control mechanisms and the ribosome population switching between periods of feeding and fasting, suggesting that the intense regulation of ribosome population observed in experiments allows to maximize and maintain protein production. Finally, we find some range for the control values over which such a regime can be observed, depending on the intensity of fasting.

An Experimental Study on the Effectiveness of the Backward-Facing Step Technique on Small-Scale Horizontal-Axis Wind Turbine Rotor Blades

The aim of this research work was to explore how modifying the design of small-scale HAWT rotor blades through the backward-facing step technique affects their efficiency under varying wind speeds. The study involved altering step parameters such as location, length, and depth to create four distinct stepped blade shapes and enhance the aerodynamic performance of a rotor with a diameter of 280 mm. A specific blade profile, NREL S822, was selected to meet both aerodynamic and structural criteria. The rotor models were examined at a Reynolds number of 4.7 × 104 for wind speeds between 8.5 and 15.5 m/s and tip-speed ratios between 2 and 5. The experimental results indicated that for certain geometric step parameter values, the efficiency of the rotor model (B3) increased by approximately 47% compared to the base model (B1), particularly for tip-speed ratios lower than around 3.2. However, beyond this point, the rotor efficiency dropped significantly, reaching approximately 60% in one case. Additionally, a hybrid rotor model (B6) was generated by combining the shape of the rotor model (B4) with the most efficient rotor model from the literature, generated using the leading-edge wavy shape technique. This hybrid rotor model enhanced rotor efficiency for specific values of tip-speed ratio and also ensured its smoother operation. Overall, the rotor model (B2), distinguished by smaller step parameter values and a shift as well as broadening of the power coefficient curve towards lower tip-speed ratio values, exhibited a higher peak power coefficient, approximately 1.4% greater than the base rotor (B1). This increase occurred at a lower tip-speed ratio, allowing the rotor to operate with higher efficiency across a broader range of tip-speed ratios.

Reparameterizing Litter Decomposition Using a Simplified Monte Carlo Method Improves Litter Decay Simulated by a Microbial Model and Alters Bioenergy Soil Carbon Estimates

AbstractLitter decomposition determines soil organic matter (SOM) formation and plant‐available nutrient cycles. Therefore, accurate model representation of litter decomposition is critical to improving soil carbon (C) projections of bioenergy feedstocks. Soil C models that simulate microbial physiology (i.e., microbial models) are new to bioenergy agriculture, and their parameterization is often based on small datasets or manual calibration to reach benchmarks. Here, we reparameterized litter decomposition in a microbial soil C model (CORPSE ‐ Carbon, Organisms, Rhizosphere, and Protection in the Soil Environment) using the continental‐scale Long‐term Inter‐site Decomposition Experiment Team (LIDET) dataset which documents decomposition across a range of litter qualities over a decade. We conducted a simplified Monte Carlo simulation that constrained parameter values to reduce computational costs. The LIDET‐derived parameters improved modeled C and nitrogen (N) remaining, decomposition rates, and litter mean residence times as compared to Baseline parameters. We applied the LIDET litter decomposition parameters to a microbial bioenergy model (Fixation and Uptake of Nitrogen – Bioenergy Carbon, Rhizosphere, Organisms, and Protection) to examine soil C estimates generated by Baseline and LIDET parameters. LIDET parameters increased estimated soil C in bioenergy feedstocks, with even greater increases under elevated plant inputs (i.e., by increasing residue, N fertilization). This was due to the integrated effects of plant litter quantity, quality, and agricultural practices (tillage, fertilization). Collectively, we developed a simple framework for using large‐scale datasets to inform the parameterization of microbial models that impacts projections of soil C for bioenergy feedstocks.

Online water quality monitoring: a case study in the umbulan drinking water supply system, East Java, Indonesia

Conventional systems that monitor the supply system periodically are considered to be very inadequate. This can cause the water supply distributed to the community to be of poor quality. Therefore, this study aims to evaluate water quality periodically by measuring water parameters such as pH, chlorine and turbidity for 30 days using an online system and portable unit. Portable tools used to measure pH, turbidity and residual chlorine are as follows, namely pH meters (Hanna, HI98017), Turbidity Meters (Hanna, HI 98703), Residual Chlorine meters and measurements with an online system using "Supervisory Control and Data Acquisition”. The average parameter value of the results of online daily monitoring for a month for the pH parameter was a minimum 6.92, a maximum of 7.46, a minimum turbidity of 0.08 nephelometric turbidity unit (NTU) and a maximum of 0.94 NTU. While the residual chlorine minimum of 0.29 mg/L and a maximum of 0.58 mg/L. To determine the accuracy of the offline measurements, measurements were also performed with a portable device four times a month. The comparison of the measurement results is very small, which is the difference in pH parameters is between 0.37-0.50, turbidity is between 0.05-0.21 NTU, and residual chlorine is 0.002-0.006 mg/L. Offline measurements using the portable device are consistent with the online daily monitoring. Future research should focus on optimizing sensor technology for enhanced accuracy and reliability, and developing automated data analysis algorithms to streamline evaluation processes.

Precursor influence on the raman spectrum of KNNLiTaLa0.01 prepared by two different methods

This work presents a study of ceramics with the (K0.44Na0.52Li0.04)0.97La0.01Nb0.9Ta0.1O3 composition through their Raman spectra. In the previous studies [1], this particular composition has shown good permittivity and piezoelectric parameter values that justify a deeper investigation. Two sets of samples of these ceramic compounds were prepared using different methods. The first set was prepared using a classical solid-state reaction of oxides and carbonates, as described in Ref. 2. The second set was prepared using the NaNbO3 as a precursor. The Raman spectra of the samples obtained by the direct ceramic method consisted of 4 modes. In contrast, the spectra of the samples obtained using the precursor showed a shift of the wavenumber of the A1g(ν1) mode peak towards lower values and consisted of six modes with the appearance of two additional IR modes, F1u(ν3) and F2g(ν4). Notably, the use of the precursor preparation route led to important improvements resulting in a more straightforward method than that of Saito et al. [3].

Techno-economic assessment and wind energy potential of Nagad in Djibouti

The use of small scaled horizontal and vertical axis wind turbines in urban installation is increasing over the world. However, in Djibouti, the latter is still in the development phase. The paper presents a techno-economical analysis and wind energy potential for the period of five years (2015-2019) in Nagad based on actual measured wind speed data collected every 10 min at 10 m height. The energy pattern factor method has been used to estimate the Weibull parameters. With this method, the mathematical complexity is reduced with a minimization of the error at any heights and locations when calculating the wind power density. At 50 m height, the shape parameter showed a small variation for different periods. The scale parameter values of 7.78 m/s and 4.8 m/s were obtained in the hot and cold seasons, respectively. The results showed that the Nagad site is suitable for wind power development. According to the economic viability, RX30, Vestas V20, Enercon, Nordex N27, and Vestas V44 wind turbines are recommended for the Nagad site due to their low energy price ranging from 0.05$/kWh to 0.31$/kWh. This is 2-6 times cheaper than the average local tariff of electricity in Djibouti.