Proper Control Research Articles

Preliminary Screening of Brucella Antibodies in Sera of Persons in Contact with Animals in Mahlab 2-Hilat Koukou, Khartoum, Sudan in 2022

Brucellosis remains a major zoonosis worldwide. This study was intended to estimate Brucellosis prevalence among people living and working in a high stocking density area (Mahlab 2) and risk factors. A cross-sectional study was done among randomly selected males and females in the area of Mahlab 2. Data was collected using questionnaires and laboratory investigations. Blood samples were collected from participants. The Rose Bengal Plate (RBP) test was used for the detection of Brucella antibodies in serum samples and a modified Rose Bengal Plate (mRBP) test was used for confirmation. A total of 69 participants were enrolled in this study. The majority of those participants were between 18–29 years of age. The seropositivity of patients’ blood samples using these tests, was 28.4%. Socio-demographic characteristics, occupation, clinical signs of disease, types, and size of herds reared by animal owners, sanitary practices, and awareness about zoonosis, Brucellosis, and symptoms of Brucellosis showed no significant correlation with seropositivity among patients’ blood samples for Brucellosis. It is recommended that surveillance and extension programs should be carried out to evaluate the magnitude of Brucellosis and to increase awareness about it. For proper control and prevention to decrease the incidence in animals, hence decreasing the incidence in humans, animal vaccination is essential.

Determination of Estimation Accuracy of Voltage Profiles Required for Proper Voltage Control by On-Load Tap Changer in Distribution Systems

The introduction of a large number of photovoltaic systems to distribution systems has increased the complexity of the voltage profile. It is thus necessary to manage voltage at a higher system level. For this purpose, the voltage profile of the distribution system can be calculated using state estimation and the voltage can be controlled based on the estimated values. Many methods for estimating voltage profiles using state estimation have been developed. However, the estimation accuracy of voltage profiles required for proper voltage control has not been discussed. If the assumed required estimation accuracy is too high, then more meters than necessary will be installed, unnecessarily increasing costs. Conversely, if the assumed required estimation accuracy is too low, voltage control equipment will not operate properly, and voltage violations may occur. Thus, it is important to determine the required estimation accuracy of voltage profiles for proper voltage control. In this paper, the estimation error of the voltage profile is expressed using a probability density function, and the estimation accuracy of voltage profiles required for proper voltage control is examined. A numerical case study was performed on a distribution network model with 2160 consumers, and revealed the following. To prevent voltage violations, an estimation accuracy of voltage profile that is approximately 10 times lower than that of the estimation accuracy based on current measurement equipment data is sufficient. To minimize the number of tap operations, an estimation accuracy needs to be improved by 70% compared with the estimation accuracy based on current measurement equipment data.

Soft start‐up control of four‐level hybrid‐clamped converters with DC voltage source

SummaryThe four‐level hybrid clamp converter (4L‐HCC) is one of the next‐generation multilevel topologies due to its simplified structure and excellent performance. However, it consists of several DC‐link and flying capacitors, which must be precharged to the rated voltage before the normal operation. Without proper control, those internal capacitors could easily induce inrush currents and cause system fatal failure due to the unsymmetrical circuit structure. This paper proposes soft start‐up control methods for both single‐phase and three‐phase HCCs. The precharging mathematical models of DC‐link and flying capacitors are established. A straightforward algorithm using the selected switching states and rotating regions is developed to build precharging circuits properly. A full‐scale simulation model and a downscale laboratory prototype of the 4L‐HCC are established to validate the superiority of the proposed method. Results demonstrate that the proposed approach is effective in charging all capacitors through internal elements rapidly with suppressed and controllable charging currents.

Molecular Profile of Metallo-β-Lactamase Producing Bacterial Isolates from Clinical Samples; South-South Nigeria Perspective

One of the major clinical problems regarding β-lactam antibiotics resistance is attributed to metallo-beta-lactamases (MβL), which are a group of enzymes that is a subset of beta- lactamases belonging to group B of the Ambler classification, which causes hydrolysis of carbapenems. The study was conducted to check the prevalence of MβL and its genes (IMP, VIM, and NDM) among Gram-negative isolates. Methods. 312 clinical samples (urine and wound) were cultured, and antimicrobial susceptibility testing was performed using the conventional disk diffusion method. MβL-phenotypic detection was uncovered by standard bacteriological techniques, MβL genes were amplified using pre-determined conditions set on an AB19700 Applied Biosystem thermal cycler. Results. 157 (56.1%) Gram-negative and 123 (43.9%) Gram-positive were isolated. Escherichia coli 32 (11.4%) and Pseudomonas aeruginosa 32 (11.4%) were the most predominant. Providencia stuartii 3 (1.1%), Klebsiella ornitholytica 2 (0.7%), and Stenotrophomonas maltophilia 1 (0.4%) were some of the less predominant isolates. Imipenem and Ertapenem were the most sensitive, while Gentamicin, Amoxicillin-Clavulanate, and Ceftriaxone were the most resistant. Twelve species (7.6%) were identified as MβL producers. The VIM gene (12: 100%) was the predominant gene, followed by the NDM gene (6: 50%) and the IMP gene (2: 16.7%). Conclusions. The detection of blaVIM, blaNDM, and blaIMP genes in South-south Uyo is really worrisome, and proper infectious control measures should be taken in order to prevent outbreaks of MβL-producing Gram-negative bacteria isolated in Uyo, South South Nigeria.

A holistic framework for improving the prediction of reverse osmosis membrane performance using machine learning

Accurate prediction and modeling of RO membranes performance is crucial in desalination processes for proper process control and operation. Existing models do not consider all process parameters, leading to less understanding of the parameter's importance. In this study, 5 non-ensemble and 7 ensemble machine learning models were employed to predict the performance of RO membrane. Data from a modern RO desalination plant in the UAE was utilized for the models' building. Thirteen input parameters, including operational parameters, water characteristic parameters, and time-dependent parameters, were used to predict salt rejection. The results suggested that ensemble techniques are more capable of predicting the performance of RO membranes. Among ensemble methods, the XGBoost model was found to outperform other models. Recursive feature elimination was integrated with Shapley additive explanation analysis to gain insights into the most influential predictors and confirm the model's ability to comprehend the RO membrane mechanism. The findings highlighted that five parameters are critical for predicting RO membrane performance and could be prioritized for future monitoring to provide timely membrane performance warnings: the membrane's age, feed water temperature, pressure, feed water flow, and chloride concentration. It also indicated that maintaining lower temperatures, increasing feed water pressure, and increasing feed flow can improve process efficiency. The optimal XGBoost model was found to have an outstanding predictive performance with a high R2 (94.75) and a low RMSE (0.181). Ultimately, the framework proposed by this study can serve as a tool to simplify and understand complex membrane processes.

Ilizarov Fixator-Assisted Management of Neglected Femur Fractures by Open Intramedullary Nailing: A Case Series.

Fourteencases of NFFspresented to Kalinga Institute of Medical Sciences, Bhubaneswar, India, between January 2020 and June 2022 were recruited for the study. After preoperative evaluation and explanation of available treatment options to patients, they were operated on with a two-stage procedure of Ilizarov fixator application, followed by intramedullary interlocking nailing, with a period of gradual distraction in between. They were then followed up for a minimum of 12 months to assess functional and radiological outcomes. The average time for all of the fractures to heal was 25.2weeks. The average knee flexion increased from 28.2degrees before surgery to 87.1degrees after surgery. All 14 patients could walk with complete weight bearing on the operated limb postoperatively after proper pain control measures were taken.The mean Tegner Lysholm knee score was 77.8. There was residual limping in six of the cases, which could be attributed to muscle atrophy and/or shortening in the affected limbs. In three cases, skin blisters were formed due to the acute nature of the distraction, but they all healed with a scab and scar, otherwise uneventfully. The shortening, in 13 cases, came down to 4 cm or less, which was managed with a shoe raise. The one case with a residual 5 cm shortening had a short, limping gait, and it was attributed to an extremely overriding osteopenic femur preoperatively. A two-stage operation with distraction by an Illizarov fixator followed by an intramedullary fixation provides the basic advantage of not having to excise an excessive amount of bone, which may be required in primary open reduction and intramedullary fixation. It also allows the patient to carry on his daily activities as mobilization is not restricted, which is the case in an individual to whom skeletal traction is applied. Hence, in any NFFcase, this algorithm of management can be considered a frontrunner in the comprehensive management of disability and deformity.

THE EXPERIENCE OF THE EAEU AND THE RUSSIAN FEDERATION ON CUSTOMS REGULATION OF THE INTERNATIONAL ELECTRONIC COMMERCE

The ever-growing volume of international e-commerce poses a number of challenges to national governments related to the assessment of the fiscal component of this category of goods, competition issues of national and foreign online sellers. Attempts are being made to form a separate category of e-commerce goods that does not relate to either trade or non-trade turnover, methods and principles of customs regulation of e-commerce goods are being formed. The draft amendments to the EAEU СС revealed significant differences in the customs regulation of goods transported within the international electronic commerce in trade and non-trade turnover. Customs regulation of e-commerce in trade is developing in the direction of finding new and improving existing technological solutions for customs operations, organizing the interaction of state regulatory authorities with participants in foreign economic activity, ensuring proper customs control and further speeding up customs operations. In non- trade turnover, the introduction of a separate category of e-commerce goods primarily raises the question of the differences between this new category and goods for personal use. The issues of customs regulation of e-commerce goods in the EAEU, primarily intended for the personal use of individuals, are considered in order to systematize the created methods of such regulation, analyze the principles of e-commerce goods movement across the customs border and the main directions of development of customs regulation of international e-commerce in the EAEU and in the Russian Federation, as well as develop recommendations for further formation the legal basis for the movement of electronic commerce goods.

Noncollocated robust output regulation of an unstable heat equation with recycle

In this article, we study the output regulation of an unstable heat equation with recycle, where the right boundary heat flux is fed back to the other end through a recycle loop, and the reference signal and the disturbances in all channels are generated by an exosystem with known frequencies. By designing a static feedback with the noncollocated observation and choosing the proper control gain, we stabilize the heat system without disturbances. Then we solve the regulator equation and construct an observer based on the tracking error to obtain the robust output feedback regulator. The closed-loop system is proved to be well-posed and uniformly bounded, and the regulated output tracks the reference signal exponentially. The numerical simulations are carried out to demonstrate the effectiveness of the proposed control.

Therapeutic Effects of Nettle Leaf: An Indigenous Vegetable

Stinging Nettle (Urtica dioica L.; family Urticaceae) is extensively used species by traditional societies of Temperate and Tropical Asia, Europe, Northern America and Northern Africa. As food, the species shows nutritional as well as immunity modulating benefits. It has shown positive benefits for treating various diseases, such as BPH, diabetes, anemia, asthma, hypertension, kidney problem, cancer, etc.; although these claims are based on different doses, followed by type and duration of intervention. There is a need to take-up more coordinated researches and validation studies in future so that applicability of nettle could be established properly against various diseases as well as proper quality control and toxicological investigations is required to assure the stability and safety of the clinical uses.

A Numerical Study of Codimension-Two Bifurcations of an SIR-Type Model for COVID-19 and Their Epidemiological Implications

We study the codimension-two bifurcations exhibited by a recently-developed SIR-type mathematical model for the spread of COVID-19, as its two main parameters —the susceptible individuals’ cautiousness level and the hospitals’ bed-occupancy rate— vary over their domains. We use AUTO to generate the model’s bifurcation diagrams near the relevant bifurcation points: two Bogdanov-Takens points and two generalised Hopf points, as well as a number of phase portraits describing the model’s orbital behaviours for various pairs of parameter values near each bifurcation point. The analysis shows that, when a backward bifurcation occurs at the basic reproduction threshold, the transition of the model’s asymptotic behaviour from endemic to disease-free takes place via an unexpectedly complex sequence of topological changes, involving the births and disappearances of not only equilibria but also limit cycles and homoclinic orbits. Epidemiologically, the analysis confirms the importance of a proper control of the values of the aforementioned parameters for a successful eradication of COVID-19. We recommend a number of strategies by which such a control may be achieved.

Modified recurrent equation-based cubic spline interpolation for missing data recovery in phasor measurement unit (PMU).

Smart grid systems require high-quality Phasor Measurement Unit (PMU) data for proper operation, control, and decision-making. Missing PMU data may lead to improper actions or even blackouts. While the conventional cubic interpolation methods based on the solution of a set of linear equations to solve for the cubic spline coefficients have been applied by many researchers for interpolation of missing data, the computational complexity increases non-linearly with increasing data size. In this work, a modified recurrent equation-based cubic spline interpolation procedure for recovering missing PMU data is proposed. The recurrent equation-based method makes the computations of spline constants simpler. Using PMU data from the State Load Despatch Center (SLDC) in Madhya Pradesh, India, a comparison of the root mean square error (RMSE) values and time of calculation (ToC) is calculated for both methods. The modified recurrent relation method could retrieve missing values 10 times faster when compared to the conventional cubic interpolation method based on the solution of a set of linear equations. The RMSE values have shown the proposed method is effective even for special cases of missing values (edges, continuous missing values). The proposed method can retrieve any number of missing values at any location using observed data with a minimal number of calculations.

Occurrence, distribution, sources, and risk assessment of organophosphate esters in typical coastal aquaculture waters of China

This study monitored 20 organophosphate esters (OPEs) in water and sediment from three typical mariculture bases (Yunxi Marine Ranching (YX), Hangzhou Bay (HZB), and Zhelin Bay (ZLB)) and Meiliang Bay (MLB) of Taihu Lake in China, focusing on the spatial distribution and sources of OPEs. Moreover, the occurrence and risk of OPEs in fishes from ZLB were evaluated. The ∑OPE concentrations in waters followed the order MLB (591 ng/L) > YX (102 ng/L) > HZB (70.0 ng/L) > ZLB (37.4 ng/L), with tri(1-chloro-2-propyl) phosphate (TCIPP), triethyl phosphate (TEP), and tri(2-chloroethyl) phosphate (TCEP) being the dominant OPEs. Significantly higher ∑OPE concentrations were found in sediment in MLB compared to the other three areas with similar levels. The decreasing concentrations of OPEs from nearshore to offshore areas in HZB and MLB indicated that terrigenous input is the main source of OPEs. The even distribution of OPEs in YX and ZLB combined with PCA analysis suggested ship traffic or aquaculture activities are also potential sources. The ∑OPE concentrations in fishes ranged from 0.551–2.45 ng/g wet weight, with TCIPP, tri-phenyl phosphate (TPHP), and TCEP being the main OPEs. Hydrophobicity was a key factor affecting the sediment-water distribution coefficients and the bioaccumulation factors of OPEs. The human exposure to OPEs through consumption of fishes from ZLB had a low health risk.

Illegal privatisation of critical infrastructure facilities: Problematic aspects and ways to solve them

The relevance of the subject of study is due to the practical importance of protecting critical infrastructure facilities in the context of increasing potential threats from criminal encroachments associated with the illegal privatisation of such facilities. The purpose of the study is to analyse the current state of criminal legal protection of critical infrastructure from illegal privatisation, develop separate recommendations on the specifics of organising an investigation into the illegal privatisation of critical infrastructure objects, and provide proposals for improving the national system for protecting critical infrastructure from illegal privatisation. The methodological approach to the study was based on using a diagnostic method, by which privatisation is considered both as a social and legal phenomenon. Methods of analysis, dogmatic, formal-legal, modelling, comparative-legal are also used. The study provided for a comprehensive review and examination of the current state of regulatory regulation of the protection of critical infrastructure facilities from illegal privatisation in the criminal legal dimension. It is established that in Ukraine, it is insufficient and needs to be improved. Proposals on criteria for assigning critical infrastructure objects to privatisation processes, creating legal mechanisms for their alienation into private ownership and ensuring proper state control over their further functioning are substantiated. The study focuses on the specifics of starting a pre-trial investigation of the illegal privatisation of critical infrastructure facilities and organising a pre-trial investigation, considering the forensic classification of criminal offences committed during the privatisation process. It is proposed to supplement Article 233 of the Law of Ukraine on criminal liability with a separate qualification composition, which would establish criminal liability for the illegal privatisation of critical infrastructure facilities, providing for the commission of this socially dangerous act of punishment in the form of imprisonment. The results obtained are of practical importance in the development and substantiation of theoretical provisions, conclusions and recommendations for improving the national system for protecting critical infrastructure from criminal offences

Challenges and proposed solutions for optical reading on point-of-need testing systems

A broad spectrum of application fields, including human and animal health, food safety and environmental monitoring, require performing real time, on-field chemical determinations, a concept known as point-of-need testing (PONT). In the case of infectious diseases, it allows for early diagnosis, which usually enables better treatment options for the patient, and permits early outbreak detection and intervention with proper control measures. PONT solutions are usually developed on microfluidic chips, preferably with no extra equipment, as to lower their cost, ease their delivery and portability. However, equipment-free PONT is not always feasible, since off-chip operations (e.g., pumping or heating) might be required and provided by the so-called analyzers. A typical example is the hardware for optical reading, which is the subject of this perspective article. Firstly, the state-of-the-art is briefly analyzed considering the solutions provided by both academy and industry. Special emphasis is made on the smartphone-based approaches that use no additional hardware (add-ons) for optical reading. Smartphones are the straightforward option, since they can replace a number of operations typically done by analyzers. The issues arising from using smartphones without add-ons are classified into variability sources and technical challenges. Finally, a set of methods for dealing with these challenges is proposed and briefly discussed. Simpler systems will be more easily adopted by more users, for a broader range of application cases, and will let PONT be a more powerful tool for improving disease diagnosis and outbreak management.

Assessment of a Novel Real-Time Bio-Liquor Circulation System for Manure Management and Mitigation of Odor Potential in Swine Farming.

Recently, circulating biologically treated manure in slurry pits has been used as an odor reduction technology, but few successful results have been reported, due to the lack of proper control strategies for bioreactors. This study was conducted to investigate the performance of the developed real-time controlled bio-liquor circulation system (BCS) at farm scale. The BCS was operated sequentially as per swine manure inflow (anoxic, aerobic, and settling) circulation to the slurry pit. Each operational phase was self-adjusted in real-time using a novel algorithm for detecting the control point on the oxidation reduction potential (ORP) and pH (mV)-time profiles, the nitrogen break point (NBP), and the nitrate knee point (NKP) in the aerobic and anoxic phases, respectively. The NH4-N in the slurry manure was thoroughly removed (100%) in the bioreactor, optimizing the duration of each operational phase by accurately detecting real-time control points. The newly developed real-time BCS decreased the nitrogen and organic matter in the slurry pit by >70%, and the potential ammonia and methane emissions by 75% and 95%, respectively. This study highlights that improved BCS that utilizes ORP tracking and pH (mV)-time profiles can effectively optimize BCS operation, and thereby reduce malodor and GHG emissions from swine farms.

Compositional tailoring of indium-free GZO layers via plasma-enhanced atomic layer deposition for highly stable IGZO/GZO TFT

Oxide semiconductor-based thin-film transistors (TFTs) are promising candidates for display backplanes and memory device applications. To achieve high device performance and sustain the electrical properties under prolonged operation, it is important to overcome the mobility–stability trade-off in oxide TFTs. Here, we propose a bilayer-structured semiconductor stack formed by plasma-enhanced atomic layer deposition (PEALD), where an indium-free gallium zinc oxide (GZO) film is grown on top of indium gallium zinc oxide (IGZO), to be implemented in top gate devices. Applying a GZO layer (with optimum Ga to Zn ratio) between the IGZO and the gate insulator (GI) resulted in two major effects: interface engineering and band alignment modulation. While maintaining a sufficiently large field effect mobility (31.9 cm2 V−1 s−1), considerable improvements in device reliability were observed concerning positive-bias thermal stress (PBTS) and negative-bias illumination stress (NBIS) compared to TFTs incorporating IGZO single layers. This suggests that proper composition control through PEALD in the bilayer oxide semiconductor TFT may help achieve an appropriate balance between mobility and reliability.

Impact of Injection Gas on Low-Tension Foam Process for EOR in Low-Permeability Oil-Wet Carbonates

Low-tension gas (LTG) flooding has been proven in lab-scale experiments to be a viable tertiary enhanced oil recovery (EOR) technique in low-permeability (~10 mD) oil-wet carbonates. Work carried out previously almost exclusively focused on water-wet cores. The application of LTG in oil-wet carbonates is investigated in this study along with the impact of a hydrocarbon (HC) mixture as the injection gas on oil–water microemulsion phase behavior. The optimum injection gas fraction (ratio of gas injection rate to total injection rate of gas and water) for the hydrocarbon gas mixture in oil-wet carbonates regarding the oil recovery rate was determined to be 60% as it resulted in around 50% residual oil in place (ROIP) recovery. It was shown that proper mobility control can be achieved under these conditions even in the absence of strong foam. The effect of HC gas dissolution in oil was clearly shown by replacing the injection HC gas with nitrogen under the same conditions. Furthermore, the importance of ultra-low interfacial tension (IFT) produced by the injection gas and surfactant slug is proven by comparing injection at sub-optimum salinity to injection at optimum salinity.

Investigating the impact of indoor environmental quality and internal design on students' satisfaction in Tehran and North Cyprus dormitories

PurposeThis study was conducted to investigate the impact of indoor environmental quality (IEQ) and internal design on the performance of students in university dormitories in Tehran and North Cyprus.Design/methodology/approachUsing a survey questionnaire, 298 students living in student dormitories in Tehran and North Cyprus were surveyed for data collection.FindingsResearch has shown that the academic performance and well-being of students are heavily impacted by factors related to IEQ and internal design. The study conducted in Tehran and North Cyprus has identified the most effective components of IEQ and internal design for student dormitories. The study suggests that proper ventilation, furniture design, temperature control and lighting design are key factors that significantly affect IEQ and internal design. Control and lighting design are key factors that significantly affect IEQ and internal design.Originality/valueOriginality: The study utilizes a comparative study designed to analyze the differences and similarities between the two locations.

COMPARATIVE ANALYSIS OF LEVEL MEASUREMENT METHODS

In industrial processes, the processes of material extraction, its transfer, storage, quantity study, processing, and distribution are quite complex. Nowadays, each of these processes is performed with the help of automated systems. Automated systems speed up operations, reduce human error, and simplify management. Tanks are used to store materials. Measuring the amount of materials is very important in the industries and applications where it is used or stored for various reasons: Inventory management: Accurate measurement of material quantities helps businesses and organizations manage their inventory effectively. This is important to ensure a continuous supply of products and avoid shortages or overstocks. Financial control: material monitoring allows companies to control their costs related to supply and storage. It helps you budget, track costs and optimize purchasing decisions. Prevention of leaks and spills: Accurate level measurement helps detect unexpected changes that may indicate leaks or spills. Early detection of such incidents is important to prevent environmental pollution and for safety. Preventing Damage to Equipment: Proper quantity maintenance is essential to prevent damage to pumps, valves, and other equipment used in the handling and handling of materials. Quality control: In some industries, material quality can be affected by factors such as temperature changes, which can be observed as level changes. Accurate measurement of quantity ensures product quality. Safety: Keeping the correct amount of material in storage tanks and other containers is critical to preventing fires, ruptures and explosions. Proper control of the level of flammable liquids such as chemicals and oil is essential to minimize safety risks. In summary, quantification of materials is essential for effective management, safety and compliance in industries where they are used or stored. It prevents environmental pollution, ensures efficient operations and minimizes safety risks associated with flammable liquids. Keywords: transmitters, measurement of quantities, ultrasonic waves, hydrostatic pressure, microwave signals.

An integrated numerical and analytical model to understand the effect of relative phase in a dual-port solid-state microwave heating process

The utilization of multi-port solid-state microwave heating systems presents promise in improving heating performance but lacks a deep understanding of the effect of source phase difference. This study developed an integrated numerical and analytical approach that allows efficient modeling and a better understanding of multi-mode wave interactions with source phase differences. First, two numerical models simulated the complex electric fields of individual-port microwave heating processes. The simulated nodal electric fields were used as inputs in the analytical model to predict the resultant power dissipation for dual-port heating with arbitrary source phase differences. The integrated approach was validated by comparing the predicted nodal electric field and power densities with numerical modeling results. The phase-dependent nodal and volumetric average power revealed wave-like patterns with great variances. The constructive, destructive, and interference effects were influenced by the source phase differences, emphasizing the importance of proper control of source phases for efficient and uniform heating.