bluuebunny/crossref_metadata_2025 huggingface dataset:
Studies on In vitro Antioxidant and Anti-Inflammatory Activities of Crinum jagus Leaves and Bulb Extracts
Authors: Alawode T. T. , Lajide L. , Owolabi B. J. , Olaleye M. T.
Published: October 2019

Aims: The current study investigates the leaves and bulb extracts of Crinum jagus for antioxidant and anti-inflammatory activities.

Place and Duration of Study: Department of Chemistry, Federal University of Technology Akure, Nigeria between June 2016 and September 2017.

Methodology: The leaves and the bulb of the plant were subjected to successive extraction using hexane, ethylacetate and methanol. The phytoconstituents and total phenol contents were determined. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging and ferric reducing antioxidant properties of the extracts (compared to that of the standard drug Ascorbic acid) were also determined. The membrane-stabilizing properties of the extracts, compared to that of indomethacin, were used to measure their anti-inflammatory properties.

Results: Phytochemical screening indicated the presence of flavonoids, alkaloids, tannins, saponins and terpenoids in the extracts. The total phenolic content of the extracts ranged between 33.230 and 98.340 gallic acid equivalence/g sample with the ethylacetate extract of the bulb having the highest phenol content. In the DPPH assay, the IC50 values of the extracts ranged between 0.503 and 1.050 with methanol extract of the leaves possessing the highest DPPH scavenging activity. The ferric reducing activities of the extracts ranged between 3.61 and 40.000 mg ascorbic acid equivalent / g of the sample with the ethylacetate extract of the bulb possessing the highest activity. Among the extracts screened for anti-inflammatory activity, the methanol extract of the leaves had the highest membrane stabilizing activity with value of 99.74 ± 0.68 at 0.5 mg/ml compared to indomethacin with a value of 52.65±1.18 at the same concentration.

Conclusion: The leaves and bulbs of C. jagus could be sources of antioxidant and anti-inflammatory compounds.
Distribution of Income (Including Minimum Wage); Comparison of Societies as Studied by a Molecular-Dynamics Algorithm and Analytical Techniques
Authors: Stallinga Peter
Published: October 2019

In this research we tried to answer the question: How to optimize the total production of economy. For finding the answer we used two postulates: First, a worker is incentivated to work if it pays off. When in the income ranking the neighbor below earns less and the one above earns more the worker will work harder and produce more. The productivity of the worker is proportional to this ’derivative’ in the income curve. (Note: a worker’s salary is not assumed necessarily proportional to his productivity). The second postulate depends on who is in control of the production process. In highly-simplified naming: In capitalism, the capital takes the decisions, in a democracy the people do, by vote. We also simulated a dictatorial system in which decisions can be imposedby a (benevolent) dictator.

We used these ingredients in evolutionary computation. Starting with an arbitrary initial distribution, we make random small changes to it and if the total production increases, a decision will be made whether to implement these changes. This procedure is repeated until the distribution is stable. Remarkably, the outcomes for ’democracy’ and ’capitalism’ are similar. Capitalism and democracy go hand-in-hand together: One person getting all income, two people working, and most not working and not receiving. These results are also analytically found.

In ’communism’, nobody works and everybody perishes. In a ’dictatorial’ system we can optimize production for the benefit of the people, and come to the conclusion that the introduction of minimum wages is beneficial, and these should be 50% of the average income.
Efficient Thermal Cycle Undergoing Adiabatic Contraction Based Work by Releasing Heat
Authors: Garcia Ramon Ferreiro
Published: October 2019

By means of observational evidence it is shown that, among the vast amount of heat-work interactions occurring in closed process based transformations, there exists the possibility of doing a transformation characterized by doing useful mechanical work by contraction based compression, while increasing the internal energy. Such thermodynamic transformation has never been considered in processes. However, in reality closed contraction based compression process are physically possible in which net work is produced by contraction of a thermal working fluid while fulfilling the fundamental laws. Thus, the objective is therefore to analyze heat-work interaction modes in closed processes conducted by heat addition, heat extracting and net work done by the process. Therefore, this analysis focuses on the feasible thermodynamic transformations contributing to the achievement of efficient closed processes based thermal cycles. The proposed cycles are characterized by performing mechanical work both in the expansion phase due to heat addition, and in the compression phase due to heat releasing. The cycles achieved are characterized by operating with closed thermal processes in which both transformations with isochoric heat addition and isochoric heat extraction are associated with useful mechanical work at high performance. The analysis of the cycle between top working temperatures ranging from 350 to 700 K while botom temperature approaches 300 K has been carried out, corroborated by experimental validation for low temperatures, in the order of 350 degrees Kelvin through a test bench designed specifically for this task. It is also worth noting that the thermal efficiency is independent of the temperature ratio. Therefore the results indicate that for lower temperatures below 690 K, the thermal efficiency of the cycle exceeds the Carnot factor, which is an efficient means of recovering residual or low-grade heat efficiently.
Modelling and Simulation of Deposit Slip Mode of Bank Cash Deposit Transactions Using Hierarchical Timed Coloured Petri-Nets
Authors: O. Olusanya O. , O. Omidiora E. , O. Olabiyisi S. , A. Ganiyu R.
Published: October 2019

Significant investments are being made yearly to improve service quality and delivery in banking systems to minimise customers' dissatisfactions with long waiting time due to overcrowding. However, most existing empirical studies to address this problem employed the method where the system was modelled and then developed a program that will simulate, analyse and validate the developed model. This paper conceptualised modelling bank cash deposit transactions characterised by Deposit Slip (DS) using Hierarchical Timed Coloured Petri Nets (HCPN). The HTPC model developed was simulated using Coloured Petri Nets tools. The model was validated by comparing the simulated results with the real average flow time of the customers and utilisation rate of servers using statistical t-test at p< 0.05.

This model is useful for bank decision makers in capacity building to enhance service quality and delivery.
Equilibrium, Kinetics and Thermodynamics of the Bleaching of Palm Oil Using Activated Nando Clay
Authors: Joseph T. Nwabanne, , Chijioke E. Onu, , Okwudili C. Nwankwoukwu,
Published: October 2019

The effectiveness of Nando clay in the bleaching of palm oil was studied in this work. The clay was prepared by activating it with hydrochloric acid. The bleaching was carried out at different temperatures, adsorbent dosage and particle sizes. The result suggests that increase in temperature and adsorbent dosage increases the bleaching efficiency while the increase in particle size decreases the bleaching efficiency. Both the pseudo-first-order and the pseudo-second-order kinetic models describe efficiently the experimental data of the bleaching process. Intra-particle diffusion though involved in the adsorptive bleaching mechanism, is not the sole rate-limiting step in the bleaching of palm oil with activated Nando clay. The equilibrium data were described better by Langmuir and Freundlich models. The enthalpy, entropy and activation energy were determined to be 6.127 KJ/mol, 3.982 KJ/mol and 15.281 KJ respectively. The free energy was found to vary between- 3.999 to- 3.760 KJ/mol. The result indicates that bleaching efficiency of up to 96% can be obtained with the activated clay as an adsorbent.
The Impact of Meteorological Conditions on the Value of Fresh and Hardened Concrete
Authors: Chukwuemeka Daniel Ezeliora, , O. Adinna B. , V. Anayo Ezenwa,
Published: October 2019

The learning scrutinizes the influence of meteorological situations on fresh and case-hardened concrete formed in the South East, Nigeria. The variables considered in the research are temperature as well as relative humidity. The meteorological condition parameters were gained from Nigerian Metrological Agency in Lagos, Nigeria. The middling yearly temperature oscillated 26.39ºC to 32.49ºC was used as a control for the experiment. Slump and strength tests were conducted on concrete samples and results exposed that workability and compressive strength of the concrete was affected by temperature and relative humidity. It was discovered that concrete manufactured in the sunrise hours (9 am-12 noon) when the temperature and relative humidity were little have better quality than those manufactured in the late afternoon (2-4 pm) as portrayed by the results of the tests on the tables. However, the research acclaims that Professionals and other stakeholders in the construction practice should be aware that temperature and relative humidity partake to influence the quality of concrete during production on site. The research also inaugurates that the suitable time to produce high-quality concrete is between the hours of 9 am-2 pm and any other time will call for the use of admixture to produce concrete of similar quality although of a higher cost thus, affecting the budget of the project. In conclusion, professionals in practice are recommended to ensure effective supervision during concrete production.
Comparative Analysis of Mono-Factorial Effects on Compressive Strength of Sandcrete Block Produced at Various Curing Age in the Warm Humid Climate of Nigeria
Authors: Uche Felix Ikechukwu
Published: October 2019

Quality of a composite material like sandcrete block is basically a function of the basic properties of the constituent ingredients, mix ratio relationship and its production characteristics. This study, investigate the effects of change in quantities of the constituent ingredient on compressive strength of sandcrete blocks produced at various curing ages in Owerri Metropolis. Field survey was conducted in the area to determine the production characteristics of the blocks marketed in the area. Based on the prevalent nominal mix ratio of the block, mix design on the constituent ingredients of the block based on box-wilson symmetric composite plan B3was adopted. Results of the strength from each experimental set of the design were used to formpolynomial regression models of blocks cured at various ages. Findings show that the average compressive strengths of the 7-day, 14-day, and 28-day old cured blocks are 1.578 N/mm2, 1.604 N/mm2, and 1.975 N/mm2.Mono-factorial analysis shows that at its respective age of curing, cement and water factors have stronger effect on the strength of the block than sand factor. The nature of their influences is positive, and more linear than quadratic and mutual interaction relationships. The relationship of mutual interaction between the cement and water factors is seen only in the models of the 7-day and 28-day curing ages in the study. Since the strength of the block increases with increase in the age of curing, it therefore confirms the standard practice of 28-day curing age for improved quality of sandcrete block in the industry; as well as recommending mono-factorial analyses on the effects of the independent factors of the mix designed blocks cured age 28-day age, towards optimum composition of the sandcrete mix ingredients for the desired quality of the blocks produced in the study area.
Switching-Algebraic Analysis of Multi-State System Reliability
Authors: Rushdi Ali Muhammad Ali , Al-Amoudi Mohamed AbdulRahman
Published: October 2019

Multi-State systems are systems whose outputs are multi-valued (due to multiple levels of capacity or performance) and (possibly) whose inputs are also multi-valued (due to multiple performance levels or multiple modes of failure). These systems are a generalization of binary or dichotomous systems that have binary or two-valued outputs and inputs. The multi-state reliability model generalizes and adapts many of the concepts and techniques of the binary reliability model, and naturally ends up with sophisticated concepts and techniques of its own. This paper explores the possibility of simply analyzing a multi-state system by reformulating or encoding its inputs in terms of binary inputs and evaluating each of its multiple output levels as an individual binary output of these alternative inputs. This means that we dispense with multiple-valued logic in the analysis of a multi-state system, since this system is now analyzed solely via switching algebra (two-valued Boolean algebra). The wealth of tools and techniques of switching algebra are now used (without any modification or adaptation) in the analysis of the multi-state system (at the cost of an expanded input domain). The paper makes its point though the analysis of a standard commodity-supply system, whose multi-valued inputs are expressed in terms of physically-meaningfully binary inputs. The analysis is made possible through the use of advanced techniques for deriving probability–ready expressions together with the employment of large-size Karnaugh maps and utilization of multiplication tables, symmetric switching functions, and Boolean quotients. Though the system studied involves twelve binary input variables, its manual analysis is completed successfully herein, yielding results that exactly agree with those obtained earlier via automated methods, and are possibly less prone to the notorious effects of round-off errors.
Efficiency Improvement for Ordinary Least Square and Orthogonal Regression-An Application in Chemical Engineering
Authors: Bhat Khurshid A.
Published: October 2019

Regression analysis plays indispensable role in QSAR/QSPR, chemical Engineering, science & technology and research projects. Best fit regression models are constantly a challenge to the researchers, efforts are taken to minimize the error components so that the predictability and efficiency of models increase. Presence of high error component eventually upset the future research and forecasting of the facts. In this paper a technique is introduced that reduces the error component and improves the predictability and efficiency of the model.
Neonatal Incubator Embedded Temperature Observation and Monitoring Using GSM
Authors: Al-Sawaff Zaid H. , Yahya Yahya Zakariya , Kandemirli Fatma
Published: October 2019

In order to reduce the risks of death rates, neglecting by the observers, and sometimes the little number of the medical staff in hospital, A monitoring system based microcontroller in neonatal incubator was developed in this article. An interfacing process is made between the infant, infant incubator, and the computer, by taking the temperature readings and send the results to doctor's or the person who in- charge's phone through Short Messages Service, and to a personal computer PC, with sound alarm on the incubator, every given period of time; A temperature sensor is interfaced with a configured single inline module SIM of phone, the temperature reading that obtained from interfacing method is combined with the readings of the incubator sensor, then the final result will be taken from the microcontroller because it will be more accurate than the incubator’s thermometer.

This system was designed only to check and give an alarm if there was any unaccepted change in temperature due to the normal temperature ranges.
State of Readiness of Nigerian Construction Industry towards Digital Transformation: The Construction Professionals’ Perception
Authors: Ezeokoli F. O. , Onyia C. I. , Bert-Okonkwor C. B. N.
Published: October 2019

Aim: This study examines the extent of readiness of Nigeria construction firms toward digital transformation within the study area.

Study Design: It was a survey research, questionnaires containing information relating to digital Technologies, trend and transformation were administered randomly to selected construction practitioners in Anambra State, Nigeria.

Place and Duration of the Study: The study was conducted in Anambra State, Nigeria for a period of 6 months.

Methodology: A total of 84 questionnaires were administered to selected respondents; 80 copies were completed, returned and found useful, thus, giving a response rate of 95%. Data collected were analysed and presented using mean, percentages, relative importance index (RII), bar charts and pie charts.

Results: The study found out that 63% of construction professional is satisfied with their firm readiness to digital transformation. However, the application of digital technologies skills and its transformation in the study area is still at foundation level. The use of mobile and social technologies (83%), entrepreneurship (73%) and Customer experience & strategic thinking (59%) are common in the study area while InMemory Databases skills (36%), Cloud Computing (39%) and Big Data Analytics (44%) are rare. Furthermore 35%, 53% 1% and 11% of the firms are planning to kick up digital transformation, undergoing some forms of digital transformation, attained or don’t see the need for digital transformation respectively.

Conclusion: The study was concluded by recommending that construction practitioners should be properly sensitised on the need to understand and conceptualise on how digital transformation and technology will impact construction processes & activities and ability to manage or work within digitally-savvy environments.
Design and Construction of an Atmospheric Pressure HF Plasma Source
Authors: Rashid Mohammad Hasanur , Herokuzzaman Md , Rahman Md Masudur
Published: October 2019

Atmospheric pressure plasma sources used in many industrial, environmental, light sources, biological, and medical applications. Aiming these prospects, an effort has been remunerated for the design and construction of a cost-effective atmospheric pressure high frequency (30 KHz) plasma source. The major sections include in this source are, (i) DC power suppliers, (ii) A set of Class A push-pull power amplifiers, (iii) Ferrite core high-frequency power transformer, (iv) Impedance matching network, and (v) Electrode design for plasma production. Two power suppliers have been considered; one is a 12V DC for biasing the base of the 2N3055 power, and the other is a 90V DC for biasing the Class A push-pull power amplifier. Class A push-pull power amplifier is chosen because of its high efficiency of about 50% concerning other types of amplifiers. Ferrite core high-frequency power transformer is designed with a turn ratio of 1:3 in order to step up the voltage to a certain level for producing atmospheric pressure plasma. An impedance matching network is designed to transfer maximum power from the source to the plasma load.
Design, Fabrication and Performance Evaluation of Indigenous Fish Feed Pelletizing Machine for Low Income Farmers in Nigeria
Authors: Orimaye O. S. , Ajewole P. O. , Oni I. O.
Published: October 2019

The design, fabrication and performance evaluation of a fish feed pelletizing machine for low income farmers was carried out with the view to encourage local technology, as most of the fish feed pelletizing machines available are imported. The fish feed pelletizer is powered by an electric motor and it works by the rotation of a screw auger which propels the feed mix through a die. The screw auger is enclosed in the auger casing and is propelled by an electric motor with the aid of belt and pulleys. This auger is fed through a hopper, which is able to hold a large quantity of the feed mix at a time. The machine was tested using different die diameters of 2 mm, 4 mm and 6 mm. The test was conducted at different moisture content of 10%, 15%, 20%, 25%, 30% and 35% wet basis. The machine test results showed that the pelletizing efficiency increases as moisture content and die diameter increase. The machine throughput also increases with both moisture content and die diameter. Highest efficiency of 98% was obtained when the moisture content was maintained at 25% wet basis and the feed materials were made to pass through 6 mm die diameter. The total cost of the design and construction of this pelletizing machine was one    hundred and five thousand naira (N105, 000.00) which is still reasonably affordable by small scale famers.
Mathematical Nonlinear Goal Programming in Quality Control
Authors: Ezzat Safia M.
Published: October 2019

This paper concerned with applying suggested mathematical programming and nonlinear goal programming models to determine the producer's risk (α), consumer's risk (β) and acceptance level (c) simultaneously. The suggested nonlinear goal programming model allowed α and β values to be free and determined their values more accurately which make balance between the power of a statistical test (1-β) and level of significance α. Real quality control data are used to evaluate the performance of the suggested models . This enables decision makers in quality control to develop more accurate and free acceptance sampling plans.
Prediction of Melting Profile of Mild Steel Weld Metals Using Regression Analysis
Authors: Idiapho Onoriode K. , Biu Raphael , Odinikuku William E. , Akusu Onomine M.
Published: October 2019

The microstructure of a weldment can be maintained by ensuring a steady state homogenous melting profile of the welding operation, which includes the deposition of optimum volumes of melted filler wire and substantial part of the heat affected zones of the parent metal to form the weld pool. The melting pattern of the entire welding process should be protected from atmospheric air, so as to enhance weldment quality. In this study, the melting profile of mild steel is investigated by looking at the parent metal angular distortion bead width and penetration volumes of deposited filler and the melting efficiency was determined. Predictive models were also developed to determine the above listed melting properties by applying the regression analysis. The result obtained showed that, there is almost a perfect fit between the calculated and predicted angular distortion, as well as between the calculated and predicted volume of filler wire melted. There is also a close correlation between the calculated and predicted melting efficiency. However, for the bead width, bead penetration and volume of weld metal deposited, there were variations of values and a heterogeneous correlation between the calculated, measured and predicted values. The effects of the process parameters on the obtained properties of the melting profile were investigated and optimum process parameters were determined.
Structural Shear Behavior of Composite Box Beams Using Advanced Innovated Materials
Authors: Erfan Abeer M. , El-Sayed Taha A.
Published: October 2019

This paper presents a new conception of shear behaviour of box concrete beams reinforced by composite fabrics. For this purpose, stirrups, wire meshes as shear reinforcement were used. Seven box section concrete beams were tested using two-point loading system. Beams with tensar wire mesh exhibited increasing in ultimate failure load, shear capacity and deflection with respect to beams used fiber-glass wire mesh instead of stirrups. Nonlinear finite element analysis was conducted using finite element program of ANSYS 14.5 to verify the experimental test program. An acceptable acceptance found between the experimental and numerical results.
Sewer Water Effect on the Corrosion of Cast Iron before and after Treatment
Authors: Abdelfattah Mona A. A. , Sobhi M.
Published: October 2019

This study aimed to compare and evaluate the effects of sewer water treated by bio-filter reactors using agriculture waste and that untreated on the corrosion of cast iron pipes. The bio-filter reactor used in this study composed of two types of agriculture wastes which are a two layer of both grape stalks and rice husk. Also, the sewer water quality parameters were tested and calculated before and after treatment. The corrosion rate was tested chemically by using the weight loss technique and it was found that the rate in case of iron immersed in sewer water before treatment was higher than that immersed in treated one.
A Study of Wafer Backgrinding Tape Selection for SOI Wafers
Authors: Bacquian Bryan Christian S. , Gomez Frederick Ray I.
Published: October 2019

The continuous development and trends on thinner semiconductor packages have become the focus in the semiconductor industry. The necessity of thinner packages also demands a thinner vertical structure of the integrated circuit (IC) design. As a major contributor on the vertical structure of the IC package, die or wafer is also essential to go thinner. As the wafer goes thinner, various problems may occur during transport and even the backgrinding process, itself.

Wafer warpage is one of the main concerns during the backgrinding process. Wafer warpage varies depending on the wafer backgrinding stress and backgrinding tape (hereinafter referred to as BG tape) tension. Hence, tension between the surface protective tape and the wafer should be considered an important and critical item to consider during BG tape selection.

Different silicon wafer technology has been released to cater different functionality on different industry markets. One popular silicon technology is Silicon On Insulator (SOI) technology. SOI wafers have a step type passivation wherein the edge of the wafer is observed to have 30um thinner than its center. The stepping effect also contributes to the 0.5mm wafer warpage prior backgrinding. Evaluating the effect of BG tape selection to eliminate such warpage is discussed on this paper.
SPAMAST Smart Garbage Bin Monitoring System Using Wireless Sensor Network
Authors: Padal Jr Christopher M. , May L. Salado Mary Jean , P. Sobejana Noel
Published: October 2019

The main objectives of the project was to develop a monitoring system that displays the real-time level of the garbage inside the garbage bins using the ultrasonic sensor, a module the notifies the admin when it reached the maximum level of the garbage’s inside the garbage bin that automatically opens using servomotor  and laser sensor after detecting the objects nearer and automatically notify the users of the garbage level when the garbage bin is already full, and to capture the level of effectiveness in terms of functionality, reliability, usability, efficiency, maintainability and portability. The research locale of the project was the SPAMAST-DIGOS Campus. The system development method used by the project-developers was the modified-waterfall approach. The project team used Visual Studio 2012 as front-end and Text File as the back end of the system. Asp.Net was used for designing the user's interface. Using these applications, the project team created a Desktop Application that displays the level of the garbage inside the garbage bins which could be graphed. The result of the test taken from students, faculties, staffs and IT expert was 4.75 as the overall weighted mean which means excellent.
Modelling Rainfall Intensity by Optimization Technique in Abeokuta, South-West, Nigeria
Authors: David A. O. , L. Nwaogazie Ify , Agunwamba J. C.
Published: October 2019

The design of water resources engineering control structures is best achieved with adequate estimation of rainfall intensity over a particular catchment. To develop the rainfall intensity, duration and frequency (IDF) models, 25 year daily rainfall data were collected from Nigerian Meteorological Agency (NIMET) Abuja for Abeokuta. The annual maximum rainfall amounts with durations of 5, 10, 15, 20, 30, 45, 60, 90, 120, 180, 240, 300 and 420 minutes were extracted and subjected to frequency analysis using the Excel Optimization Solver wizard. Specific and general IDF models were developed for return periods of 2, 5, 10, 25, 50 and 100 years using the Gumbel Extreme Value Type -1 and Log Pearson Type -3 distributions. The Anderson-Darling goodness of fit test was used to ascertain the best fit probability distribution. The R2 values range from 0.973 – 0.993 and the Mean Squared Error, MSE from 84.49 – 134.56 for the Gumbel and 0.964 – 0.997 with MSE of 42.88 – 118.68 for Log Pearson Type -3 distribution, respectively. The probability distribution models are recommended for the prediction of rainfall intensities for Abeokuta metropolis.
Numerical Methods for Information Tracking of Noisy and Non-smooth Data in Large-scale Statistics
Authors: Avinash B. S. , Srisupattarawanit T. , Ostermeyer H.
Published: October 2019

In our universe, there is a presence of random bit of disorder in every field that has to be contemplated and understood clearly. This random bit of disorder in a physical system is known as noise. Noise in the field of statistics can be defined as an additional meaningless information that cannot be clearly interpreted which is present in the entire dataset. In large-scale statistics, noisy data has an adverse effect on the results and it can lead to skewness in any data analysis process, if not properly understood or handled. The adverse effect on the results is mainly due to uncorrelated (zero autocorrelation) property of noise. This makes it completely unpredictable at any given point in time, hence thorough investigation and removal of noise plays a vital role in data analysis process. In the field of engineering, measurement of experimental data obtained by using scientific instruments consists of some values that are independent of the experimental setup. One of most widely technique is the optimization methods viz, gradient descent, conjugate gradient, Newton’s method etc. Most of these methods require the determination of derivative of a function specified by the dataset (using finite-difference approximation). If the noisy data is approximated using a specific finite difference method this results in the amplification of noise present in the data. In order to overcome the aforementioned problem of amplification of noise in the derivative of a function, various regularization methods are employed. The parameter that plays a vital role in these methods are termed as regularization parameter. One of the most important technique used in the field of regularization is known as total variation regularization. This review aimed at gathering the disperse literature on the current state of various noises and their regularization methods.
An Integrated Approach to the Management of Municipal Solid Waste in a Typical City in Southwest Nigeria
Authors: A. Oni Olayiwola , Omotoso Toyin , Alo Ayowole
Published: October 2019

A study of the prevailing management of municipal solid waste (MSW) generated in Ado Ekiti, a city in the southwest of Nigeria was undertaken using desk and field studies. The composition of the MSW derived from on-site waste sampling comprised plastics (28%), food (26%), paper/cardboard (14%), metal (7%), rubber (6%), textile (6%), glass (4%), leather (4%), fines less than 10mm (3%) and wood (2%). Analysis of the MSW shows that the calorific value is greater than the required minimum value of 7 MJ/kg required for applicability of incineration. However, the criteria for a regular supply of refuse derived fuel (RDF) of at least 50,000 metric tons per year required for the applicability may not be met. Furthermore, incineration of the MSW may not be applicable due to its relatively expensive installation costs. An integrated MSW framework comprising reduction, reuse, recycling, recovery (composting), incorporation of the informal sector; public private partnership (PPP); public enlightenment and enforcement of regulatory laws on sanitation is proposed. Active participation of PPP is vital to the implementation of the framework. An engineered landfill is proposed as none exists in Ado Ekiti.
Simplified Compression Arch Action Model for R/C Beam-column Assemblages
Authors: Beshara Fouad B. A. , Mahmoud Ahmed A. , El-Mahdy Osama O. , Khater Ahmed N.
Published: October 2019

A set of analytical equations are developed for calculating the beam-column assemblage flexure action capacity and compression arching action capacity under a middle column removal scenario. The suggested equations covered most of the main parameters affecting the assemblage behavior including seismic detailing, longitudinal reinforcement ratios, concrete confinement, and the contribution of concrete flanged slabs. The proposed analytical model for predicting the flexural and compression arching action capacities is validated with a large number of experimental results. The model provides a good estimation for 79 beam-column assemblages with several geometrical, reinforcement configurations, and material parameters. The mean values of the experimental to the theoretical ratio for calculating flexure and compression arching capacities are 1.15 and 1.16, respectively. The predictions of previous compression arch action models are found to be more conservative. Finally, the proposed model is utilized in parametric studies including all key parameters that affected resistance of the beam-column assemblages against progressive collapse.
Three Phase Inverting Using Pulse Width Modulation Controlled by 6802 Motorola Microprocessor
Authors: Almashakbeh Atef
Published: October 2019

Different types of voltage sources are available in the market, but the point is how to convert any voltage to our desired waveform? For example; if we have a DC voltage source (like battery or dc generator) and we need to run AC motor (one phase or three phases) or run DC motor with special voltage, or we have an AC source (one phase or three phases) and need to run AC machine with special voltage and special frequency or run DC machine with special voltage. In simple meaning we need a connector between the sources and loads to match between them. But it should pass this conditions; efficiency, mobility, size, weight, range of operation, simple with using and cost.

This paper focuses on designing and producing a true sinewave inverter that provides premium power which is identical to (or even better than) the power supplied by the utility company with multi output. On this work we will give an explanation for type of inverter depend on output and function for it.
Lithium Storage Mechanisms and Electrochemical Behavior of a Molybdenum Disulfide Nanoparticle Anode
Authors: Li Xintong , Hao Wei , Wang Hua , Li Tianyi , Trikkaliotis Dimitrios , Zhou Xinwei , Hou Dewen , Chang Kai , Hashem Ahmed M. , Liu Yuzi , Yang Zhenzhen , Cao Saichao , Hwang Gyeong , Kyzas George Z. , Yang Shengfeng , Mullins C. Buddie , Julien Christian M. , Zhu Likun
Published: December 2024

This study investigates the electrochemical behavior of molybdenum disulfide (MoS2) as an anode in Li‐ion batteries, focusing on the extra capacity phenomenon. Employing advanced characterization methods such as in situ and ex situ X‐ray diffraction, Raman spectroscopy, X‐ray photoelectron spectroscopy, and transmission electron microscopy, the research unravels the complex structural and chemical evolution of MoS2 throughout its cycling. A key discovery is the identification of a unique Li intercalation mechanism in MoS2, leading to the formation of reversible LixMoS2 phases that contribute to the extra capacity of the MoS2 electrode. Density function theory calculations suggest the potential for overlithiation in MoS2, predicting Li5MoS2 as the most energetically favorable phase within the lithiation–delithiation process. Additionally, the formation of a Li‐rich phase on the surface of Li4MoS2 is considered energetically advantageous. After the first discharge, the battery system engages in two main reactions. One involves operation as a Li‐sulfur battery within the carbonate electrolyte, and the other is the reversible intercalation and deintercalation of Li in LixMoS2. The latter reaction contributes to the extra capacity of the battery. The incorporation of reduced graphene oxide as a conductive additive in MoS2 electrodes notably improves their rate capability and cycling stability.
Pareto‐Optimal Design of Automotive Battery Systems with Tabless Cylindrical Lithium‐Ion Cells: Resolving the Trade‐Off Between Energy, Performance, Weight, and Cost for Variable Vehicle Requirements
Authors: Pegel Hendrik , Jany Lukas , Sauer Dirk Uwe
Published: December 2024

Large‐format tabless cylindrical cells have been a top research subject within recent years. However, research so far has exclusively focused on isolated understanding of individual aspects such as the performance, safety, or cost. This study introduces a global optimization framework for battery systems with tabless cylindrical cells based on the groundwork laid within recent years. The framework is applied to gain comprehensive understanding of cross interactions between different design variables and the key performance indicators of the battery system. It was found that a well‐defined diameter exists which optimizes the battery energy for given boundary conditions. The multiobjective trade‐off between energy, performance, weight, and cost however might lead to different solutions with respect to the desired properties of the system. Small cylindrical cells with diameter less than 25 mm provide enhanced performance but lower energy and higher cost. Very large cylindrical cells with diameter more than 50 mm have less options for interconnection but provide the best cost‐saving potential. With realistic constraints, only diameters larger than 40 mm achieve Pareto‐optimal solutions. Aluminum housings are found to outmatch steel housings in nearly all properties, especially for larger diameters. Considering the widespread introduction of aluminum housings is recommended for automotive manufacturers.
Enhanced Saccharification Efficiency of Corn Straw by Laccase‐Cu2O Under Light/Dark Cycles
Authors: Xiang Yulin , Dai Chunyu , Wang Yefei , Zhang Yongbo , Cao Baowei
Published: December 2024

To strengthen the clean utilization of biomass waste, laccase modified cuprous oxide (Cu2O) composite catalyst is synthesized. The effects of catalyst type, catalyst concentration, pH, sunlight exposure time, and lighting method on the reducing sugar yield are investigated. The composite catalyst in combination with sunlight irradiation can effectively enhance the reducing sugar yield of corn straw. The optimum conditions were pretreatment time of 55 min, catalyst concentration of 58 mg L−1, pH of 5.5, enzyme hydrolysis process using a 30 DL (namely 20 min of dark/20 min of light alternating cycle for 30 h) scheme, and enzyme loading of 25 FPU g−1. Validation experiments show that the lignin removal percentage can reach 95.63%, and the reducing sugar yield can reach 124.79 mg g−1 under the optimum condition. The pretreatment and saccharification of straw executed twice are most advantageous for sugar production. Laccase‐Cu2O can be reused three times.
Combined Displacement/Intercalation Mechanism of Ag0.33V2O5 Cathode for Rechargeable Zinc‐Ion Batteries
Authors: Lee Hyeonjun , Lee Hyungjin , Hong Seung‐Tae , Chae Munseok S.
Published: December 2024

Zinc‐ion batteries are gaining recognition as viable options for energy storage systems due to their air stability, abundance, affordability, and ease of use. However, existing zinc‐storage materials primarily consist of intercalation cathode materials, necessitating the development of host structures with enhanced performance. Herein, the use of silver vanadate, Ag0.33V2O5, as a cathode material is explored and its detailed displacement/intercalation mechanism is elucidated, encompassing silver, proton, and zinc‐ion storage behaviors. Electrochemical behavior, structural analysis, and diffusion barrier calculation techniques are used to delineate cation diffusion pathways. Additionally, 3D electron density mapping is performed to visualize the cation reaction mechanism. The proposed material demonstrates an impressive reversible capacity of about 303 mAh g−1 at a current of 0.1 A g−1, along with outstanding cycle retention stability even at high current densities.
Evaluating the Potential of Multitype Energy Harvesting in New Energy Vehicles: A Systematic Review and Quantitative Analysis
Authors: Fu Yifeng , Gu Xiaohu , Cao Pan
Published: December 2024

This review presents an overview in the context of the current state of the art in energy harvesting technologies for new energy vehicles (NEVs) and delves into the significant energy losses experienced by NEVs during driving, braking, and overcoming wind resistance. Based on the different forms of energy losses, the prevalent energy harvesting technologies in the NEV domain are elucidated, with a focus on the fundamental principles of vibration energy, braking energy, wind energy harvesting, and their recent advancements in practical implementations. Vibration energy harvesting involves the conversion of mechanical energy from the suspension system into electrical energy, while brake energy harvesting captures a portion of the brake friction loss as electrical energy during braking, and wind energy harvesting utilizes wind power generators on the vehicle surface to produce electricity. By quantitatively evaluating the recovery effects of different types of systems, the report demonstrates the great potential of energy harvesting technologies to improve energy efficiency and extend the range of NEVs. Furthermore, it explores the future trajectory of energy harvesting technology, envisioning its integration as a standard feature in NEVs and heralding transformative progress in the global energy and transportation sectors.
Formalizing a Postprocessing Procedure for Linear–Convex Combination Forecasts
Authors: Monschang Verena , Wilfling Bernd
Published: December 2024

We investigate mean squared forecast error (MSE) accuracy improvements for linear–convex combination forecasts, whose components are pretreated by a postprocessing procedure called “vector autoregressive forecast error modeling” (VAFEM). Assuming that the forecast error series of the individual forecasts are governed by a stable VAR process under classic conditions, we obtain the following results: (i) VAFEM treatment bias corrects all individual and linear–convex combination forecasts. (ii) Any VAFEM‐treated combination has a smaller theoretical MSE than its untreated analog, if the VAR parameters are known. (iii) In empirical applications, VAFEM gains depend on (1) in‐sample sizes, (2) out‐of‐sample forecast horizons, and (3) the biasedness of the untreated forecast combination. We demonstrate the VAFEM capacity in simulations and for realized‐volatility forecasting, using S&P 500 data.
Early prognosis biomarkers of severe fever with thrombocytopenia syndrome
Authors: Ou Mingrong , Wang Aofan , Yu Jie , Zhao Liwei , Li Chuang , Wu Yuanyuan , Chen Yuxin
Published: December 2024

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease that results from SFTS bunyavirus (SFTSV) infection. Infection with SFTSV can activate the immune system, producing a series of inflammatory factors. Some patients, particularly those with pre‐existing conditions or at an advanced age, may experience an excessive inflammatory response, triggering systemic multi‐organ failure progressing to severe disease and, potentially, death. In recent years, extensive research has been conducted on the mechanism of SFTSV infection and its interaction with host immune responses. Additionally, a range of biomarkers with significant prognostic value for SFTS have been identified. This review provides a comprehensive summary of the latest advancements in understanding the interplay between SFTSV and host immune responses, and elucidates the role of these biomarkers in the early detection of severe cases and fatal outcomes. The insights presented aim to inform strategies for early intervention, clinical treatment, and prognostic assessment of patients with SFTS.
Terminal Care Performance of Nurses Caring for COVID‐19 Patients: A Cross‐Sectional Descriptive Study
Authors: Oh Juyeon , Kim Dong‐Hee , Kim Yujin
Published: December 2024

Aims

To identify the effects of moral distress and terminal care stress on the terminal care performance of nurses who cared for COVID‐19 patients.

Design

This study was cross‐sectional descriptive research.

Methods

Using a convenience sampling method from June to October 2022, nurses who provided terminal care for COVID‐19 patients in a Korean tertiary hospital within the last 6 months from the time of the study were selected as participants. Socio‐demographic and work characteristics of the participants were collected, and COVID‐19 moral distress, terminal care stress and terminal care performance were assessed. A total of 140 self‐report questionnaires were distributed and returned (response rate: 100%).

Results

In the terminal care performance, it was found that nurses performed relatively well in the physical area, but less well in the emotional and spiritual areas. Moral distress and terminal care stress were both positively correlated with terminal care performance for nurses who cared for COVID‐19 patients. The predictors of terminal care performance were moral distress (β = 0.27, p = 0.003), gender (β = 0.20, p = 0.015) and experience in a dedicated COVID‐19 unit (β = 0.22, p = 0.020).

Conclusions

The study identified moral distress as the most significant factor influencing terminal care performance among nurses caring for COVID‐19 patients. To enhance terminal care performance, it is crucial to address moral distress and provide clear guidelines and support, especially in the emotional and spiritual care domains. Future research should explore additional factors that may influence terminal care performance in pandemic situations.

Patient or Public Contribution

No patient or public contribution.
MRI of early rectal cancer; bisacodyl micro-enema increases submucosal width, reader confidence, and tumor conspicuity
Authors: Viktil Ellen , Hanekamp Bettina Andrea , Nesbakken Arild , Løberg Else Marit , Sjo Ole Helmer , Negård Anne , Dormagen Johann Baptist , Schulz Anselm
Published: December 2024

Purpose

To investigate the influence of a micro-enema on diagnostic performance, submucosal width, reader confidence, and tumor conspicuity using MRI to stage early rectal cancers (ERC).

Methods

In this single-center study, we consecutively included 50 participants with assumed ERC who all completed MRI with (MRin) and without (MRex) a micro-enema. The diagnostic performance was recorded for two experienced radiologists using histopathology as the gold standard. In addition, the width of the submucosa in the tumor-bearing wall, reader confidence for T-staging, and tumor conspicuity were assessed. Significance levels were calculated using McNemar’s test (diagnostic performance) and Wilcoxon’s signed-rank test (reader confidence, submucosal width, and conspicuity). Interreader agreement was assessed using kappa statistics.

Results

Sensitivity/specificity were for Reader1 91%/87% for both MRex and MRin and for Reader2 74%/87% and 89%/87%, both readers p > 0.05. The micro-enema induced a significant widening of the submucosa, p < 0.001, with a mean increase of 2.2/2.8 mm measured by Reader1/Reader2. Reader confidence in T-staging and tumor conspicuity increased for both readers, p < 0.005. The proportion of tumors with both correct staging and high reader confidence increased from 58% (29/50) to 80% (40/50) (p = 0.04) for Reader1 and from 42% (21/50) to 72% (36/50) (p = 0.002) for Reader2. Interreader agreement increased from moderate (kappa 0.58) to good (kappa 0.68).

Conclusion

The micro-enema significantly increased the submucosal width in the tumor-bearing wall, reader confidence, and tumor conspicuity and improved interreader agreement from moderate to good. Sensitivity and specificity in T-staging did not improve, but there was a significant increase in the proportion of tumors staged with both high confidence and correct T-stage.

Graphical Abstract