Maximum Allowable Research Articles

How to define the parameters of the kernel of the transverse creep

The article is devoted to the methodology for determining the parameters of the kernels of the transverse creep of the linear-viscosity materials for the minds of a folding stressed frame. Issues: One of the main tasks in the theory of viscosity is the task of choosing the structure of the kernel of decay and the assignment of parameters of the kernels. The task is actual, shards of the correct designation of unknown parameters in the present to lay down the terms of operation of structural elements.Purpose: The method of work is the development of the method of assigning the parameters of the kernels of transverse creep and the approbation of the results on the problems of analysis of the deformation of transverse creep. Implementation methodology: If the given methodology is only valid for linear materials, then at the first stage, linearity in viscous powers is entrenched. The parameters of the kernels are significant on the basis of the hypothesis of a single function of creep, the basis of which is presented in a confidence interval of 10%. In the capacity of the core of the decay of the vicorist, there is a shot-exponential kernel. The task is to reduce to the minimization of the functionality of the quadratic adjustment of the experimental data in the species of rozrachunks. On the basis of the results, it is possible to create a conclusions about the practicality of the induced technique, both for "Plaxiglass ST-1" and for other linear materials. The maximum allowance for calculation data from experimental warehouses is 5%.

Maximum Exposure Evaluation for MIMO Based on Optimization Algorithm

IEC/IEEE FDIS 63195-2 requires the maximum exposure evaluation to determine if the product meets the radiation limit requirements specified by ICNIRP. The miniaturization and integration of millimeter wave antennas make it possible to deploy antenna arrays supporting Multiple-Input Multiple-Output (MIMO) technology in mobile terminals, which brings challenges to traditional exposure compliance testing. This is caused by the complex electromagnetic environment generated around the equipment by beam focusing technology and the difficulty in determining the maximum exposure of electromagnetic exposure dose by traditional measurement methods. However, mathematical model-based evaluation methods may produce overly conservative results, limiting the maximum allowable transmit power of 5G devices and resulting in wasted system performance. In this study, we take advantage of the optimization algorithm in searching for globally optimal solutions under multivariate constraints, and its search strategy is improved to evaluate the largest exposure of millimeter wave MIMO antenna arrays in the target region.

MATERIAL SELECTION OF PROPOSED AIR RECEIVER TANK APPLIED FOR ELECTRICAL GENERATOR

Air receiver tank in electrical generator used as pressured air vessel is mainly consisted of shell cylinder and head part. This work has searched for the more suitable material to be used for the shell and head of the proposed air receiver tank because the older material (SPV 355) has some limitations. This study has been conducted based on several parameters in standard references. The calculations have applied relevant technical formulas such as corrosion factor, thickness design, and Maximum Allowable Working Pressure (MAWP). There are three types of selected materials available that are expected to yield similar previous condition parameters addressing to operational pressure 10 bar and temperature 40oC, i.e., SA-36 (Type I), SA-516 Gr 70 (Type II), and SS-304 (Type III). The economic factor is also taken into consideration. Considering the economic cost and mechanical characteristics, finally the material of Type II is selected to be the most appropriate material to replace SPV 355 material for the proposed air receiver tank. In the upcoming, this study is useful for the knowledge of material design.

Epiphytic and epigeal lichens as bioindicators of air pollution in the Burabay National Park, Kazakhstan

Abstract. Bukabayeva Z, Abiyev S, Silybayeva B, Assanova U, Sharipkhanova A, Sagdatkyzy B. 2023. Epiphytic and epigeal lichens as bioindicators of air pollution in the Burabay National Park, Kazakhstan. Biodiversitas 24: 2701-2709. Lichens are recognized as a symbiotic association between a fungus (mycobiont) and a chlorophyll-containing partner (photobiont). Because lichens receive all their nutrients from the atmosphere, they are very sensitive to air quality and can be used as bioindicators of pollution by heavy metals, organic compounds and radioactive elements in the air. This study aimed to evaluate the potential of lichens as bioindicators of the heavy metal content in the air in the Burabay National Park, northern Kazakhstan. In the period from 2018 to 2022, we studied the floristic composition of lichens in the national park. To inform air pollution level, we determined the quantitative characteristics and projective cover of an epiphytic lichen Evernia prunastri (L.) Ach. at different heights above ground level, and the heavy-metal content in an epigeal lichen Cladonia alpestris (L.) Rabenh (Syn. Cladonia stellaris (Opiz) Pouzar & V?zda) at different distances from the road edge. We identified 56 species of lichen belonging to 23 genera and 16 families on the roadsides or in the nearby forest. We found that the average number of individuals of E. prunastri decreased as the tree trunk height increased. The largest number of individuals (11.3) was observed at a height of 60 cm, and the smallest (2.5), at a height of 150 cm. The analysis of C. alpestris samples taken at different distances (50, 100, 150, 200 m) from the roadside showed that the concentrations of Pb, Cr, Cd, As, Ga, V, and ?s were high, and for all the elements studied, except for Mn and Be, exceeded Maximum Allowable Concentration. Our study demonstrates that E. prunastri and C. alpestris are sensitive to air pollution from road traffic and can be used as biomonitors of heavy metal pollution in the study area. Because of the ever-increasing anthropogenic pressure on the vegetation of the Burabay National Park, we recommend further research and monitoring of its lichen biota.

Mineralogical Study of Respirable Dust in Artisanal SmallScale Quarries of Misisi Compound, Lusaka, Zambia

Misisi compound in Lusaka is characterized by artisanal small scale quarrying activities which are often dusty in nature and prone to hazards. This study reports respirable dust concentration and the mineralogical composition of rocks in the workplace. Dust sampling was carried out with the help of gravimetric samplers at five quarries. Respirable dust samples were collected during digging, chiselling, crushing, and loading sites. The results of the sampled dust indicated high levels of respirable dust at all five quarry crushing sites. For example, based on Time Weighted Average (TWA), the respirable dust concentration at the crushing site was recorded as 12.75 mg/m3 at quarry#1 compared to the Maximum Allowable Concentration (MAC) of 5 mg/m3 of Occupational Safety and Health Administration (OSHA). The results of mineralogical testing and analyses revealed that marble was the common rock type that was being mined by most of the ASMs in the studied area. Based on the point count data analysis, marble contained 98% CaCO3 and 2% SiO2.

Health Risk Assessment of Heavy Metals in Vegetable: The Contribution of Illegal Mining and Armed Banditry to Heavy Metal Pollution in Katsina State, Nigeria

The health risk to the population from exposure to heavy metals in an area that have witnessed a surge in illegal mining activities, cattle rustling and banditry were evaluated in the current study. Moringa leaves sample from Jabiyawa village, Jibia local Government area, Katsina State, Nigeria was evaluated for the presence of heavy metals using Atomic Absorption Spectrophotometry. The health risks of the evaluated heavy metals in the sample to the population were assessed using the Target Hazard Quotient (THQ) and Health Risk Index (HRI)) to assess the possible non-carcinogenic effect and the Incremental Lifetime Cancer Risk (ILCR) for the cancer risks. The result of the mean concentration values of the evaluated heavy metals Fe, Cu and Pb from the sample falls above the Maximum Allowable Concentrations (MAC) of heavy metals in leafy vegetables. The concentrations of the other metals including Zn, Ni, Mn and Cd evaluated in the sample were within the permissible values The results of the Target Hazard Quotient (THQ) associated with the evaluated heavy metals exposure through consumption of the sample for adults and children were below 1, with exception of the THQ for the heavy metal Cu in the children population that was above 1. The combined health risks for all the metals in the sample for the adults and children population represented as the HRI were above 1. The result of the Incremental Life Cancer Risk (ILCR) for both the adults and children population shows that the heavy metal Ni is beyond the threshold of the safety limit for cancer risk. There is a health risk concern from consumption of the sample as the vegetable may contribute to the disease burden of the population.

Analysis of the corrosion rate and remaining life of the B3 waste transport roll-off tank composed of 316L stainless steel

Corrosion has eroded the shell and head of the roll-off tank used to carry B3 waste. This influence will effect on the functioning of the waste containment tanks, as well as the general safety of the public. The goal of this study was to examine the viability of employing a roll off tank by completing a visual inspection and engineering calculations using ASME VIII and API 510 standards to determine the corrosion rate and remaining life in the roll-off tank. This study employs a quantitative approach. Tank design data was acquired using SA-240/G316L material with an initial shell and head thickness of 6 mm and an actual thickness of 5.45 mm shell and 5.50 mm head. The corrosion rate and remaining life analysis yielded a Thickness Required shell value of 4.33 mm and a head value of 4.33 mm, with a shell and head Corrosion Rate value of 0.04 mpy, a Maximum Allowable Working Pressure (MAWP) value of shell and head of 0.63 Bar, and a shell and head remaining life value of 28 years and 30 years, respectively. It may be established that the roll-off tank is still operationally viable. Maintenance and testing regularly to improve roll-off tank performance

Determination of the maximum allowable active powerflow in the section taking into account the thermal conditions of power transmission lines

Subject of research: This paper assesses the possibility of introducing into the task of calculating maximum and emergency allowable active power flow, taking into account the thermal modes of overhead lines when planning electric power regimes. 
 Purpose of research: determine the effect of thermal processes in power lines on the maximum allowable active power flow in controlled sections of electric power systems.
 Methods and objects of research: Such factors influencing active power flow as ambient air temperature, which is currently corrected by the Russian Power System Operator, wind speed, solar radiation and direct heating from flowing current are considered. Simulation of steady state flow in the software package RastrWin3 and Mathcad for a 2-bus scheme with mode only taking into account the ambient temperature and the calculations of steady state flow were already taking into account variations in weather parameters, taking into account possible restrictions on the maximum load due to the modes of operation of the power system (technical feasibility generating equipment was not taken into account in the work under consideration).
 Main results of research: the result of calculation, it is clearly seen that when taking into account the thermal conditions of overhead power lines, the allowable active power flows differ by 1626 % from the values determined only when taking into account the ambient temperature.

Maximum Allowable Annular Surface Pressure (MAASP) Standards Calculations Study; a Field Case Study

Well integrity failures may arise during the production phase of a well in a field. Those failures could create a Sustained Casing Pressure (SCP), a pressure that is measurable at the wellhead that can not be bled-off. SCP has to be addressed carefully to avoid any uncontrolled fluid flow to other formation or to surface. To maintain SCP value from degrading the other barrier integrity, the pressure threshold should be known and maintained for each annulus in a well. The maximum pressure threshold known as Maximum Allowable Annular Surface Pressure (MAASP).
 This case study will calculate MAASP from three wells in X field using three known method as outlined in API RP90-2 and ISO 16530-1. API RP 90-2 define two methods in calculation MAASP (known as MAASP – Maximum Allowavle Wellhead Operating Pressure), Simple Derating Method (SDM) and Explicit Derating Method (EDM).
 The result then compared and evaluted to know the differences, trend of MAASP for each methods, and create a generalization of MAASP/depth for field rule of thumb. For A annulus, the MAASP obtained using API RP90-2 SDM and EDM method is always greater than that obtained using the ISO 16530-1 method. However, for B annulus, the MAASP obtained using the API RP 90-2 SDM method varies, occasionally being greater or less than the ISO 16530-1 method. While in C annulus, the MAASP obtained using the API RP 90-2 SDM and EDM methods is always less than the ISO 16530-1 method. The MAASP/depth generalization will be presented for MAASP ISO 16530-1.

Designing asynchronous filter with uncertain conditional probabilities for periodic discrete-time Markov jump systems

This paper is concerned with asynchronous filtering of periodic discrete-time Markov jump systems with uncertain conditional probabilities (CPs). The Markov jump process of the considered system and the stochastic process of the asynchronous filter consist of a hidden Markov model. A criterion, which enables the filtering error system to be mean-square exponentially stable and (Q,S,ℛ)-dissipative, is proposed by applying the Lyapunov function method and some inequalities. Then, two design approaches for the desired filter are developed without and with using the row sum-to-one property of the CP matrix, respectively. Based on these, two optimization algorithms are further proposed for finding maximum allowable (Q,S,ℛ)-dissipativity performance index while maintaining the solvability of the asynchronous filtering issue. Finally, the validity and lower conservatism of filter design methods are verified by numerical simulation and comparison.

Health Risk Assessment of Heavy Metals in a Vegetable Cultivated on Land Polluted through Illegal Mining

The risk of exposure to the population from heavy metals in an area that have witnessed a surge in illegal mining activities, cattle rustling and banditry were evaluated in the current study. Lettuce leaves sample from Gadirge village, Jibia local Government area, Katsina State, Nigeria was evaluated for the presence of heavy metals using Atomic Absorption Spectrophotometry. The health risks of the evaluated heavy metals in the sample to the population were assessed using the Target Hazard Quotient (THQ) and Health Risk Index (HRI)) to assess the possible non-carcinogenic effect and the Incremental Lifetime Cancer Risk (ILCR) for the cancer risks. The result of the mean concentration values of the evaluated heavy metals Fe and Pb from the sample falls above the Maximum Allowable Concentrations (MAC) of heavy metals in leafy vegetables. The concentrations of the other metals including Cu, Zn, Ni, Mn and Cd evaluated in the sample were within the permissible values. The result of the Target Hazard Quotient (THQ) associated with the evaluated heavy metals exposure through consumption of the sample for adults and children were all lower than 1, with exception of the THQ for the heavy metals Fe and Mn in the adults and children population that was above 1. The combined health risks for all the metals in the sample for the adults and children population represented as the HRI were higher than 1, the result of the Incremental Life Cancer Risk (ILCR) for both the adult and children population has revealed that the heavy metal Ni was beyond the threshold of the safety limit for cancer risk. There is a health risk concern from consumption of the sample as the vegetable may contribute to the disease burden of the population.

Energy Efficient Resource Allocation for Uplink MC-NOMA Based Heterogeneous Small Cell Networks With Wireless Backhaul

In this paper, we investigate energy efficient resource allocation for uplink multi-carrier non orthogonal multiple access (MC-NOMA) based two-tier heterogeneous networks (HetNets) with wireless backhaul. We have exploited channel diversity by assigning multiple subchannels to various MC-NOMA users (NUs), while allowing multiple NUs to use the same subchannel. We formulate a joint NU clustering, and power and subchannel allocation problem for system's energy efficiency (EE) maximization under the constraints of minimum quality of service (QoS) requirement, maximum allowable transmit power for each NU, and successive interference cancelation. The formulated problem is non-convex with fractional objective function, and therefore, to convert it into a tractable from, it is divided into two subproblems, i.e., subchannel allocation and NU clustering subproblem, and power allocation subproblem. The subchannel allocation and NU clustering subproblem is solved through a suboptimal algorithm, which exploits the channel diversity by maintaining maximum possible difference in transmit power levels of clustered NUs. Whereas for the power allocation subproblem, the EE optimization problem is convexified through Dinkelbach and successive convex approximation techniques and a closed-form suboptimal solution is obtained. The simulation results show that the proposed energy efficient algorithm outperforms the existing NOMA and orthogonal multiple access (OMA) algorithms. The proposed approach also guarantees user fairness by giving priority to the NUs with unfulfilled throughput requirements.

Analysis of metals and metalloid in commercial fish species from the Galapagos Marine Reserve: Toxicological and nutritional assessment

Aquatic pollution derived from metal presence in the Galapagos Islands could affect biodiversity and human health. This research provide a baseline on food safety in commercial fish species of the Galapagos Islands. We sampled muscle tissue of pelagic (Acanthocybium solandri) and demersal (Caulolatilus affinis, Pontinus clemensi, Hyporthodus mystacinus, and Paralabrax albomaculatus) species. Metal and metalloid concentrations per species were analyzed by Inductively Coupled Plasma Optical Spectrometry (ICP-OES). According to the Food and Agriculture Organization (FAO) regulation none of the studied species should be ingested; and according to the European Food Safety Authority (EFSA) regulation, all the studied species were above the Maximum Allowable Concentration (MAC) for Cd. According to EFSA, C. affinis should not be commercialized. Finally, A. solandri, P. clemensi and H. mystacinus do not represent a human health risk since its Margen of Safety (MoS) < 1 for people of up to 100 kg of body weight.

Cross-Layer Optimization: Joint User Scheduling and Beamforming Design With QoS Support in Joint Transmission Networks

User scheduling and beamforming design are two crucial yet coupled topics for multiuser wireless communication systems. They are usually addressed separately with conventional optimization methods. In this paper, cross-layer optimization problem is considered, namely, the user scheduling and beamforming are jointly discussed, subjecting to the requirement of per-user quality of service and the maximum allowable transmit power for multicell multiuser joint transmission networks. To achieve the goal, a mixed discrete-continuous variables combinational optimization problem is investigated with aiming at maximizing the sum rate of the communication system. To circumvent the original non-convex problem with dynamic solution space, we first transform it into a 0-1 integer and continuous variables optimization problem, and then obtain a tractable form with continuous variables by exploiting the characteristics of the 0-1 integer constraints. Finally, the scheduled users and the optimized beamforming vectors are simultaneously calculated by an alternating optimization algorithm. We also theoretically prove that the base stations allocate zero power to the unscheduled users. Furthermore, two heuristic optimization algorithms are proposed respectively based on brute-force search and greedy search. Numerical results validate the effectiveness of our proposed methods, and the optimization approach gets relatively balanced results compared with the other two approaches.

Analysis and simulation of reverse osmosis equipment: Case of La Guajira, Colombia

Energy resources and potable water are important assets for every country. Electric power produced from renewable sources can be used to provide water desalination systems and meet the energy needs of populations living in isolated and remote areas. This study models and simulates a reverse osmosis (RO) water desalination system using dynamic mathematical models in one dimension, and applies it to water sources from the department of La Guajira, Colombia. Most of the indigenous communities are concentrated in the upper and middle areas of that region, where there are brackish water sources such as groundwater wells that could undergo water purification to improve community’s quality of life. Furthermore, these areas have the best solar radiation potential in Colombia. The Yuyurupana indigenous community was chosen for the study; they are located in the rural area of the municipality of Maicao. This place has a groundwater well with 3055.77 mg/L of total dissolved solids (TDS) and average solar radiation of 4.8 kWh/m2/month. At a feed pressure of 11.65 atm, the system obtained a permeate concentration quality of 317.45 mg/L, which is below the maximum allowable according to the Colombian Ministry of Environment. The specific energy consumption (SEC) was calculated and yielded a value of 0.644 kWh/m3. It requires 152 photovoltaic solar panels and a total area of 294.9 m2 to supply electricity to the system. The mathematical models were validated by comparing results with those of previous studies found in the literature.

Illegal Mining and Armed Banditry in Katsina State, Nigeria: What is their Contribution to the Heavy Metal Pollution of a Popularly Consumed Vegetable?

The health risk to the population from exposure to heavy metals in an area that have witnessed a surge in illegal mining activities, cattle rustling and banditry were evaluated in the current study. Cabbage leaves sample from Makiya village, Jibia local Government area, Katsina State, Nigeria was evaluated for the presence of heavy metals using Atomic Absorption Spectrophotometry. The health risks of the evaluated heavy metals in the sample to the population were assessed using the Target Hazard Quotient (THQ) and Health Risk Index (HRI)) to assess the possible non-carcinogenic effect and the Incremental Lifetime Cancer Risk (ILCR) for the cancer risks. The result of the mean concentration value of the evaluated heavy metal Pb from the sample falls above the Maximum Allowable Concentrations (MAC) of heavy metals in leafy vegetables. The concentrations of the other metals including Fe, Cu, Zn, Ni, Mn and Cd evaluated in the sample were within the permissible values The result of the Target Hazard Quotient (THQ) associated with the evaluated heavy metals exposure through consumption of the sample for adults and children were all below 1. The combined health risks for all the metals in the sample for the adults and children population represented as the HRI were below 1, the result of the Incremental Life Cancer Risk (ILCR) for both the adults and children population shows that all the heavy metals have ILCR that falls within the safety limit for cancer risk. Because of the above permissible Pb concentration in the analysed cabbage leaves sample, it can be deduced that the vegetable is not safe for consumption.

Feeding level during the last week of gestation can influence performance of sows and their litters in the subsequent lactation.

This study investigated the impact of feeding level during the last week of gestation on performance of sows and their litters in the subsequent lactation. A total of 48 sows were assigned to one of six feeding levels (1.8, 2.4, 3.1, 3.7, 4.3, or 5.0 kg/d) from day 108 of gestation until farrowing. Post-farrowing, all sows were fed similarly during lactation with a gradual increase in feed allowance in accordance with Danish recommendation until it reached the maximum allowance of 9 kg/d on day 17 of lactation. Plasma samples were collected from the sows during farrowing and lactation, and sow's body weight and backfat thickness, and milk samples were taken during lactation. Litters were standardized to have 13 to 15 piglets each and weighed once weekly during lactation. Plasma concentrations of urea, acetate, and butyrate in sows linearly increased (P < 0.001), while non-esterified fatty acids linearly decreased (P < 0.001) during farrowing with increasing feeding level. Moreover, concentrations of triglycerides (P < 0.001), acetate (P = 0.007), and succinate (P < 0.001) were greater in plasma collected at the onset of farrowing compared to the end of farrowing. Conversely, concentrations of glucose, urea, and butyrate (P < 0.001) were lower in plasma collected at the onset of farrowing than at the end. Sows fed 2.4 and 3.1 kg/d exhibited greater triglyceride concentrations than those fed 3.7 (P = 0.03) and 5.0 (P = 0.02) kg/d. Sows fed 1.8 kg/d during the last week of gestation had lower milk yield in wk 1 (P < 0.001) and wk 2 (P = 0.001) of lactation compared to the other groups. Additionally, litter weight gain (P = 0.04) and litter weaning weight (P = 0.007) were lower in sows fed 1.8 kg/d compared to the other groups. The greatest milk yield, litter growth, and litter size were observed in sows fed 3.7 kg/d during the last week of gestation, whereas the estimate generated by the regression model revealed that sows should have been provided with 4.0 to 4.1 kg/d as an adequate feeding level to maximize these performances in the subsequent lactation. Interestingly, feeding level during the last week of gestation did not influence feed intake during lactation. In conclusion, this study highlights the significance of adequate feed supply (4.0 to 4.1 kg/d) during the last week of gestation in order to maximize performance of sows in the subsequent lactation.

Comparative analysis of the elemental composition of plant organs of the genus Iris L. (Iridaceae)

Plants of the genus Iris L. are promising medicinal raw materials with significant biological and pharmacological activity. The aim of this work was a comparative study of the accumulation and transfer of elements through the organs of plants of the genus Iris L. (Iridaceae). The content of As, Cd, Cr, Cu, Mn, Ni, and Pb in different parts of I. orientalis, I. pseudacorus, I. sibirica and I. spuria plants was analyzed by atomic absorption. It has been established that in the absence of soil pollution, irises accumulate arsenic in concentrations exceeding the maximum allowable. The accumulation of chromium in the raw material was also above the maximum allowable concentration for a number of study options. The efficiency of element transfers from the soil to the root system varied significantly. Iris rhizomes absorbed nickel most actively. The assimilation ability of the roots is also clearly expressed in relation to Pb, As, Cr, Cu, Mn. Depending on the element, accumulation in leaves is species-specific. The carrying capacity of the peduncle is most pronounced in I. sibirica, the barrier capacity is most pronounced in I. orientalis. Various types of translocations of elements in organs were revealed: acropetal, uniform, basipetal. All studied species are characterized by acropetal distribution of Pb and uniform distribution of Mn. The location of Cd may vary depending on the species. Cu is concentrated in the roots (I. orientalis, I. sibirica, I. spuria) or evenly distributed (I. pseudacorus). The revealed patterns of accumulation and distribution of elements in the organs of plants of the genus Iris make it possible to carry out a prognostic assessment of the quality of raw materials to obtain safe products.

Spaceflight Maximum Allowable Concentrations for Ethyl Acetate.

INTRODUCTION: Ethyl acetate is a simple organic compound that occurs naturally and is used industrially as a solvent. It has been detected in the ISS atmosphere and is known to off-gas from building materials. As NASA astronauts have been and will be exposed to ethyl acetate during space missions, Spaceflight Maximum Allowable Concentrations (SMACs) were developed following an extensive review of the available literature.METHODS: Toxicological data relevant to SMAC development was collected from electronic databases using principles of systematic review, and from previous assessments and reviews of ethyl acetate.RESULTS: From an initial pool of over 35,000 studies, 10 were identified as studies appropriate to support SMAC development. The toxicological properties of ethyl acetate are relatively straightforward. Ethyl acetate is rapidly absorbed and converted by carboxyesterases to ethanol. At concentrations on the order of 400 ppm for 4-8 h, most volunteers experienced mild irritation but no lasting effects. In subchronic animal studies, mild sedative effects and changes in body weight and weight gain were observed at 750 ppm and above.DISCUSSION: Numerous studies were identified to support the development of both short- and long-duration SMACs. No chronic studies were available, but the high quality of the subchronic studies and the short half-life of ethyl acetate support extrapolation to longer durations.Williams ES, Ryder VE. Spaceflight maximum allowable concentrations for ethyl acetate. Aerosp Med Hum Perform. 2023; 94(1):25-33.

A High-Gain Observer Design for Nonlinear System with Delayed Measurements: Application to a Quadrotor UAV

The paper deals with the design of a high-gain observer for nonlinear system with delayed output measurements and bounded disturbances. The new structure of the proposed observer exhibits good performance in terms of allowing a higher MAVTD (Maximum Allowable Value of the Time-Delay) compared to the existing works, where the MAVTD is limited due to the high value of the high-gain parameter. Based on the LMI technique and using Lyapunov-Krasovskii function, an explicit relation between MAVTD and the LMI tuning parameters is deduced from the stability analysis of the proposed observer. The efficiency of the proposed structure is illustrated through an application to a Quadrotor UAV and a comparison with standard and cascade high-gain observers is performed.