Equipment Units Research Articles

A mission reliability modelling method for intuitively displaying time elements

In view of the problems that the commonly used reliability block diagram modelling methods can not directly reflect the operation time elements of units and that whether an unit can be repaired or not during mission period, this paper proposes a graphical reliability modelling method that can uniformly represent the two key elements of equipment unit reliability logic relationships and its operation times, so as to improve the comprehensiveness of the display elements of reliability model and the accuracy of the logical relationship of each unit. Finally, a comprehensive example shows the feasibility of this method.

Classical and Process Intensification Methods for Acetic Acid Concentration: Technical and Environmental Assessment

This study aims to investigate, from a technical and an environmental perspective, various alternatives for acetic acid concentration for maximizing acetic acid production, its purity, and in the meantime, minimizing the energy usage and the environmental impact. Liquid–liquid extraction followed by azeotropic distillation using different solvents such as: (i) ethyl acetate, (ii) isopropyl acetate, and (iii) a mixture containing isopropyl acetate and isopropanol were first explored, using process flow modeling software. The three cases were compared considering various technical key performance indicators (i.e., acetic acid flow-rate, acetic acid purity, acetic acid recovery, power consumption, thermal energy used, and number of equipment units involved) leading to the conclusion that the usage of the isopropyl acetate—isopropanol mixture leads to better technical results. The isopropanol-isopropyl acetate mixture was furthermore investigated in other two cases where process intensification methods, based on thermally coupled respectively the double-effect distillation process, are proposed. The highest quantity of pure acetic acid (e.g., 136 kmol/h) and the highest recovery rate (e.g., 97.74%) were obtained using the double-effect method. A cradle-to-gate life cycle assessment, involving ReCiPe method, was used to calculate and compare various environmental impact indicators (i.e., climate change, freshwater toxicity potential, human toxicity, etc.). Several steam sources (i.e., hard coal, heavy fuel oil, light fuel oil, natural gas, and biomass) were considered in the environmental evaluation. The results of the life cycle assessment show a reduction, by almost half, in all the environmental impact indicators when the double effect method is compared to the thermally coupled process. The usage of biomass for steam generation lead to lower impacts compared to steam generation using fossil fuels (i.e., hard coal, heavy fuel oil, light fuel oil, natural gas).

Acting on the call for cervical cancer elimination: Planning tools for low- and middle- income countries to increase the coverage and effectiveness of screening and treatment

IntroductionAccessible planning tools tailored for low-and middle-income countries can assist decision makers in comparing implementation of different cervical cancer screening approaches and treatment delivery scenarios in settings with high cervical cancer burden.MethodsThe Cervical Precancer Planning Tool (CPPT) was developed by PATH for users to explore and compare the accuracy of screening approaches, what treatment equipment to procure, and how best to deploy treatment equipment in a given country. The CPPT compares four screening approaches: 1) visual inspection with acetic acid (VIA), 2) HPV testing, 3) HPV testing followed by a VIA triage, and 4) HPV testing followed by an enhanced triage test. Accuracy of screening outcomes (e.g., true positives, false positives) is based on published sensitivity and specificity of tests to detect cervical precancerous lesions. The CPPT compares five scenarios for deploying ablative treatment equipment: 1) cervical precancer equipment at every location a woman is screened (single visit approach), 2) equipment only at a hospital level, 3) a single unit of equipment in each district, 4) allowing two districts to share a single unit of equipment, and 5) equipment placed at select district hospitals paired with mobile outreach. Users can customize the CPPT by adjusting pre-populated baseline values and assumptions, including population estimates, screening age range, screening frequency, HPV and HIV prevalence, supply costs, and health facility details.ResultsThe CPPT generates data tables and graphs that compare the results of implementing each of the four screening and five treatment scenarios disaggregated by HIV status. Outputs include the number and outcomes of women screened, cost of each screening approach, provider time and cost saved by implementing self-sampling for HPV testing, number of women treated, treatment equipment needed by type, and the financial and economic costs for each equipment deployment scenario.ConclusionThe CPPT provides practical information and data to compare tradeoffs of patient access and screening accuracy as well as efficient utilization of equipment, skilled personnel, and financial resources. Country decision makers can use outputs from the CPPT to guide the scale-up of cervical cancer screening and treatment while optimizing limited resources.

Research on the Reliability of a Core Control Unit of Highway Electromechanical Equipment Based on Virtual Sensor Data.

The printed circuit board (PCB) is the core control unit of electromechanical equipment. In order to determine the influence of the coupling vibration caused by vehicle–road interaction on the PCB reliability of roadside electromechanical equipment, first, the dynamic load of the vehicle tire is solved by establishing the dynamic model of a vehicle road. Then, the acceleration response data generated by road vibration are obtained by solving the road finite element model. Finally, the power density spectrum of the acceleration response is taken as input excitation, and the deformation response of the PCB under vehicle–road coupling vibration is analyzed. The experimental results show that when the vehicle is driving close to the roadside, the vibration caused by vehicle–road coupling will lead to a large deformation of the PCB, and the deformation value reaches 0.170 mm, which can cause structural damage to the PCB. This shows that the vehicle–road coupling vibration can affect the reliability of the roadside electromechanical equipment; thus, the optimal design of the PCB layout is created. After optimization, the first-order modal frequency of the PCB is increase by 5.4%, which reduces the risk of the components breaking away from the PCB substrate.

Distributed Estimation Approach for Tracking a Mobile Target via Formation of UAVs

This paper considers distributed estimation methods to enable the formation of Unmanned-Aerial-Vehicles (UAVs) that track a moving target. The UAVs (or agents) are equipped with communication devices to receive a beacon signal from the target and share information with neighboring UAVs. The shared information includes the time-of-arrival (TOA) of the beacon signal from the target and estimates on the target’s location. Every UAV processes the received information from the neighbors using a single-time-scale distributed estimation protocol. This differs from multi-time-scale protocols that require (i) many consensus iterations on a-priori estimates, (ii) fast communication among agents (in general, much faster than the sampling rate of the target dynamics), and thus, more-costly communication equipment and processing units. Further, our approach outperforms most single-time-scale methods in terms of observability assumption as these methods assume that the target is observable via the measurement data received from neighboring UAVs (referred to as local-observability). This requires more communications among the sensors. In contrast, our approach is only based on global-observability assumption, and thus, requires less networking (only strong-connectivity) and communication traffic along with less computational load by data-processing once at the same time-scale of sampling target dynamics. We consider modified time-difference-of-arrival (TDOA) measurements with a constant output matrix for the linearized model. UAVs make a pre-specified formation, and by estimating the target’s location via these measurements, move along with the target. Note to Practitioners—Inspired by recent development in industrial UAVs along with emerging progress in low-cost processing units, fog computing systems, and wireless communications, this paper considers mobile tracking of a moving target via a group of wireless-connected autonomous drones. In the classical tracking methods, which are prone to single-point-of-failure, all the sensors need to send their information to a ground central station over a long-range and costly data-transmission channel. In contrast, by collaborative tracking the processing and decision-making are distributed among a swarm of drones equipped with onboard miniaturized electronic parts such as sensors, microcontrollers, microprocessors, and communication units. This article provides an efficient algorithm to enable such drones to autonomously track the moving target in real-time. Note that the cost and tracking ability of the UAV swarm are directly determined by the computational efficiency and communication burden of the estimation algorithm. In this regard, most available estimation algorithms are over budget and even infeasible due to the need for fast data-transmission channels, fast CPUs, and high network traffic. Our proposed estimation technique outperforms similar algorithms in terms of required communication bandwidth, data-transmission rate, and computational resources, which considerably reduces the hardware cost and improves tracking efficiency in real-time large-scale applications. We show the feasibility and efficiency of our distributed tracking method by simulation.

The Specifics of the Compilation of the Calculated Load Combinations in the Assessment of Seismic Resistance of Steel Supporting Structures of Nuclear Power Plant Equipment and Piping

The seismic resistance of nuclear power plant equipment and piping is determined, inter alia, by the seismic resistance of their steel supporting structures. During the operation of the nuclear power plant power unit, mechanical loads from the elements installed on them are transferred to the steel supporting structures of the equipment and piping. During an earthquake, seismic loads are added to these loads. By state building codes, when considering steel structures in special operating conditions (in particular, exposed to seismic hazards), it is necessary to comply with additional requirements that reflect the features of these structures. Given this, the issue of developing approaches to the compilation of load combinations in assessing the seismic resistance of steel supporting structures of nuclear power plants equipment and piping is acute, taking into account the specific conditions of their operation. The paper is also relevant as it is one of the priority areas of science and technology under the legislation of Ukraine. The development of approaches to the compilation of the calculated load combinations will contribute to the improvement and development of methods for assessing the safety of nuclear power facilities. The paper presents the results of the review of the provisions of state building codes on the calculated combinations of loads when assessing the strength of steel structures. Approaches to the compilation of the calculated load combinations in assessing seismic resistance of steel supporting structures power units of nuclear power plants equipment and piping taking into account the specific conditions of their operation have been developed.

SIMULATION MODELING OF IRONMAKING AND STEELMAKING PROCESSES AT CHEREPOVETS STEEL MILL OF PAO SEVERSTAL

This paper presents the results of running the model of ironmaking and steelmaking processes at Cherepovets steel mill of PAO Severstal. The model was developed using Anylogic software. The main goals of the work were: modeling of changes in the quantities of raw materials/ finished products; determining optimal productivity values for the equipment units involved in the process chain; identification of the process stages which may be overloaded in the process of modeling with further debottlenecking; conducting experiments on increasing throughput of the process stages (by increasing productivity or accumulation of accepted raw materials at the warehouses); checking achievability of the business plan targets for production of hot metal and steel. The main results of the work done are as follows: it is possible to get a 50% increase in the quantity of pellets transported by conveyors from tilting cars to blast furnaces considering the conveyor repairs; the system of conveyors would allow transportation of materials (sinter and concentrate) in case of increase in the blast furnaces productivity by 7.8% versus the current level; it has been established that the BOF shop productivity is influenced by geometry of slabs produced, line speed of the slab casting and tap-to-tap time; minimum tap-to-tap time at which the BOF shop productivity would be at maximum level is 36 minutes. Further reduction of tapto-tap time may be advised only if the casting machines are upgraded.

A novel process model for developing a scalable room-level energy benchmark using real-time bigdata: Focused on identifying representative energy usage patterns

Existing building energy ratings are typically derived with the annual average energy consumption of the buildings. This approach may be appropriate for formulating community-level energy strategy at the macro level, but it cannot be directly linked to occupant behavior for energy savings at the micro level. In light of this, this study aimed to propose a novel process model for developing a scalable room-level energy benchmark using real-time bigdata, which focused on identifying representative energy usage patterns and encouraging occupant behavior change for energy savings. When creating a scalable room-level energy benchmark, three views were taken into account: (i) space unit as perceived by occupants, for which space-specific energy usage datasets were classified based on space attributes; (ii) time unit to which occupants can respond simultaneously, for which hourly energy usage datasets were used; and (iii) equipment unit to which occupants can precisely respond, for which energy usage datasets by different types of electrical installation and appliance were utilized. Based on the scalable room-level energy benchmark, the main findings can be summarized: (i) five representative energy usage patterns were identified using k-means clustering method; (ii) the year-round distributions of the five representative patterns were investigated by month and weekday; and (iii) the annual average variance (or uncertainty) of the room-level scalable energy benchmark was determined to be 19.6%. By providing spatio-temporal information on energy usage patterns in real time, it is expected that occupant behavior change can be voluntarily encouraged to save energy in buildings using the proposed approach.

A Framework for In-Service Life Extension of Hydroelectric Generation Assets

Abstract The integrity assessment of aged or worn out large electromechanical equipment units, such as in hydroelectric generators, for possible life extension has been identified as a growing challenge in the electrical power generation industry worldwide. Although the available recommended practices provide a general assessment process, it is necessary to have more detailed guidelines. This can be achieved by adding relevant theories and models which can capture time-dependent equipment unit degradation more precisely. Seeking to fulfill this gap, this work aims to present a framework that combines several techniques of data analysis, reliability, and decision-making to support engineers, operators, and managers in the often-complex decision process, regarding whether or not to extend the time in service of an equipment or system, thus postponing the moment of a scheduled maintenance shutdown. To demonstrate the application of the proposed framework, a case study is presented considering simulated scenarios based on data and information from a real Hydroelectric Power Plant. The results show how the reliability of the components and the remaining useful life of those in fault can impact the decision-making regarding the in-service life extension of a system.

Numerical analysis of heat and mass transfer in micropolar nanofluids flow through lid driven cavity: Finite volume approach

In this article, the heat and mass transfer mechanism of micropolar nanofluid embedded with Buoyancy force and magnetic field across an enclosure has been analyzed. Mass, energy, and momentum equations are required to construct the mathematical model to evaluate the efficacy of thermal performance of nanoparticles.The motivation for this study is to improve heat and mass transfer efficiency in heat transfer equipment and heat recovery units in industrial and engineering processes. Given the signification of dimensional analysis, 2D model is set up in their dimensionless context. In addition, the finite volume approach (FVM) is employed for numerical simulations. The thermophoresis and Brownian motion parameters has been considered for the temperature field, as proven via simulation. As a result of the random mobility of nanoparticles, more heat is emitted inside the enclosure. Furthermore, mass diffusivity and Schmidt number are inversely related,so that mass diffusion inside the cavity is faster for small values of Schmidt number. Additionally, it is discovered that a high vortex viscosity parameter produces a weak concentration field and has significant behavior when thermophoresis parameter and Reynolds number are significant. The simulations are captured in graphical form, and their results are explained in detail.

Fire releases micro- and nanoplastics: Raman imaging on burned disposable gloves

Raman imaging can effectively characterise microplastics and nanoplastics, which is validated here to capture the items released from the plastic gloves when subjected to a mimicked fire. During the COVID-19 pandemic, large quantities of personal protective equipment (PPE) units have been used, such as the disposable gloves. If discarded and poorly managed, plastics gloves might break down to release secondary contaminants. The breakdown process can be accelerated by burning in a bushfire or at the incineration plants. During the burning process, the functional groups on the surface can be burned differently due to their different thermal stabilities. The different degrees of burning can be distinguished and visualised via Raman imaging. In the meantime, at the bottom of the burned plastics, microplastics and nanoplastics can be generated at a significant amount. The possible false Raman imaging on microplastics and nanoplastics is also discussed, by effectively extracting and distinguishing the weak signal from the background or noise. Overall, these findings confirm the importance of effectively working waste incineration plants and litter prevention, and suggest that Raman imaging is a suitable approach to characterise microplastics and nanoplastics.

ОСОБЛИВОСТІ ПОБУДОВИ ІНФОРМАЦІЙНИХ КАНАЛІВ БАГАТОРІВНЕВИХ ІНФОРМАЦІЙНО-ВИМІРЮВАЛЬНИХ СИСТЕМ ДІАГНОСТУВАННЯ ВУЗЛІВ ЕЛЕКТРОТЕХНІЧНОГО ОБЛАДНАННЯ З УРАХУВАННЯМ ВИМОГ КОНЦЕПЦІЇ SMART GRID

Some peculiarities of constructing information channels, which are a part of multilevel information-measuring systems for diagnostics of electrical equipment, are considered. The primary attention in the report is paid to the consideration of primary diagnostic information measurement channels, as well as the block of training aggregates, where the infor-mation about defects and possible modes of operation of some electrical equipment units is stored. One of the possible options for building a primary measurement channel focused on using wireless measurement sensors, which are consis-tent with the use of international standards, has been considered. The description of diagnostic features for determining the technical condition and classification of possible defects in individual nodes of electrical equipment concerning their modes of operation is briefly described. Based on accepted diagnostic attributes, the models of representation of training sets, which correspond to different technical states of electrical equipment units for different modes of opera-tion, are considered. Ref. 10, fig. 3.

Controllable synthesis and structural design of novel all-organic polymers toward high energy storage dielectrics.

As the core unit of energy storage equipment, high voltage pulse capacitor plays an indispensable role in the field of electric power system and electromagnetic energy related equipment. The mostly utilized polymer materials are metallized polymer thin films, which are represented by biaxially oriented polypropylene (BOPP) films, possessing the advantages including low cost, high breakdown strength, excellent processing ability, and self-healing performance. However, the low dielectric constant (ε r < 3) of traditional BOPP films makes it impossible to meet the demand for increased high energy density. Controlled/living radical polymerization (CRP) and related techniques have become a powerful approach to tailor the chemical and physical properties of materials and have given rise to great advances in tuning the properties of polymer dielectrics. Although organic-inorganic composite dielectrics have received much attention in previous studies, all-organic polymer dielectrics have been proven to be the most promising choice because of its light weight and easy large-scale continuous processing. In this short review, we begin with some basic theory of polymer dielectrics and some theoretical considerations for the rational design of dielectric polymers with high performance. In the guidance of these theoretical considerations, we review recent progress toward all-organic polymer dielectrics based on two major approaches, one is to control the polymer chain structure, containing microscopic main-chain and side-chain structures, by the method of CRP and the other is macroscopic structure design of all-organic polymer dielectric films. And various chemistry and compositions are discussed within each approach.

TECHNICAL AND ECONOMIC RATIONALE FOR THE USE OF TURBULA TYPE MACHINING MACHINES IN POLISHING THE SURFACE OF SMALL POLYMER POLYMERS

A method of wet polishing of polymer parts using a galvanizing machine with a complex spatial movement of the working tank type «Turbula» is proposed. According to the proposed method, the main stage of polishing the surface of the parts is carried out by abrasive ceramic bodies of complex geometric shape with the addition of fine pumice in the implementation of mixed cascade-waterfall mode of movement of the bulk working medium. This method of processing parts is considered highly productive, the processing time of parts averages 15 hours of continuous operation of the machine, which is several times faster than when processing parts in rotating drum drums or vibrating machines. The latter are characterized by low productivity of the relevant technological operations. The feasibility study of the method of wet polishing of polymer parts using a galvanizing machine with a complex spatial movement of the working capacity of the «Turbula» type for the implementation of the technological operation of polishing the surface of polyester buttons was performed analytically. The expected annual economic effect from the implementation of the developed method of wet polishing of polymer parts using a galvanizing machine with a complex spatial movement of the working capacity of the «Turbula» type, which will amount to UAH 14,059.8 per two units of equipment, is calculated. This method of processing can be used to improve the surface quality of any polymer parts with the possibility of achieving the appropriate value of the roughness of their surface. The obtained research results can be used in design bureaus of relevant enterprises for the manufacture of small polymer parts, the surface quality of which is determined by organoleptic method, as well as in design bureaus of machine-building enterprises specializing in the development of galvanizing equipment.

Quality parameters of interfaces of technological equipment units

The influence of design and technological measures to stabilize and increase the interaction of mating surfaces of technological equipment units on the quality of manufactured products is investigated. Keywords: technological equipment, accuracy, reliability, durability, movable and fixed joints, friction surfaces.serdobintsevyup@mail.ru

A DAMAGE ANALYSIS OF FRONT FINAL DRIVE PLANETARY GEAR BACKHOE LOADER CASE 580 SN

Today's technology continues to develop and these developments are applied to the field of heavy equipment, therefore it is necessary to analyze one of the components of the Backhoe Loader Case 580SN heavy equipment unit, namely the Front Final Drive Planetary Gear. The Backhoe Loader is one of the heavy equipment units designed to be able to carry out one of the functions and activities of the construction process which is heavy when carried out by human labor, such as: transporting, lifting, loading, moving, digging, mixing, and so on in an easy, fast, efficient and safe way. This research method analyzes and directs spaciousness, this is because this company has a lot of heavy equipment, one of which is the Backhoe Loader which is the object of research. The results of field analysis Damage to the Front Final Drive Planetary Gear Backhoe Loader Case 580 SN is caused by a lack of Final Drive lubricant when the unit is running, this is because the O-Ring Final Drive is wearing out so that the lubricant seeps out.

EFISIENSI KERJA WHEEL LOADER KOMATSU WA 200-5 DI PABRIK BRIKET TANJUNG ENIM PT. BUKIT ASAM Tb

Based on business development in the Tanjung Enim Briquette work unit related to the production of Activated Carbon and Carbon Anodes, to support production, work efficiency is needed on the heavy equipment unit, namely Wheel Loaders. In addition, by obtaining work efficiency data, it is possible to evaluate the work of the wheel loader in its operations at the Tanjung Enim Briquette Factory PT. Bukit Asam Tbk. So that there is an increase and optimization of the work/operational quality of the Wheel Loader to achieve the production target. At the Tanjung Enim Briquette factory itself the wheel loader unit plays an important role in supporting the production of Carbonized Briquettes, Non-Carbonized and serves various types of work in the briquette factory such as filling hopper, material mixing or blending, transporting clay and loading raw coal stock. The data collection process for 16 days started on August 2 until August 27, 2021 with the average wheel loader working efficiency of 86.12% in the good category.

Integrated sizing and scheduling of an off-grid integrated energy system for an isolated renewable energy hydrogen refueling station

When designing an isolated renewable energy hydrogen refueling station (HRS), it is important to consider the electrical, heating and cooling demands of the supporting building as it is crucial for maintaining the stable HRS operation. Therefore, this paper proposed a new structure of off-grid integrated energy system (OIES) for an isolated renewable energy HRS, which can meet the hydrogen load of the market and the three kinds of loads of the supporting building. The OIES in question consists of wind generators, PV panels, batteries, electrolyzers, heat storage tanks, hydrogen tanks, and absorption chillers. A mixed integer quadratic constrained programming (MIQCP) model of the OIES is built based on the minimization of the total life cycle cost (TLCC). It is built to obtain the optimal solution for sizing and the equipment units’ scheduling strategy. To accord with the actual situation, the electrical, heating, and cooling loads of the supporting building in the simulation are obtained by the EnergyPlus software. Furthermore, the ‘community’ hydrogen demand is obtained by the HOMER software. The results indicate that the proposed structure meets a wide array of energy demands and is more sensible solution when compared to other configurations with one component less. In addition, sensitivity analyses of the influence of economic data, meteorological data, and hydrogen load on TLCC are performed. These results show that the capital and replacement cost of the PV panels are the major economic factors influencing the TLCC. They also confirm that the PV is the system’s main component due to a high correlation between the hourly hydrogen demand per year and the hourly solar radiation per year. Lastly, the effects of meteorological data and hydrogen load are also quantitatively analyzed.

METHODS FOR EVALUATION OF EFFICIENCY OF RESTORATION OF WEAPONS AND MILITARY EQUIPMENT OF THE AIR FORCE ARMED WEAPONS

The high efficiency of the use of military units and individual units (groups) of the Air Force of the Armed Forces of Ukraine in the conduct of combat operations (operations) is directly related to the constant support of weapons and military equipment in full combat readiness for use. For constant support there is a logistics system with functions of providing military units and units of armament and military equipment, their maintenance and repair. The article presents methods of assessment of efficiency of restoration of ground models of armament and military equipment of the Air Forces of the Armed Forces of Ukraine both as part of the group of troops and in military units and individual units. Methods allow to assess the effectiveness of the recovery of armament and military both as an integral system of logistics of the group of troops and military unit (a separate unit), the effectiveness of each component (technical reconnaissance, evacuation, repair)and, also, based on the results of the received data, to develop recommendations to improve the effectiveness of the components and the restoration of armament and military equipment in general.

Understanding Performance of a Vulnerable Heterogeneous Edge Data Center: A Modeling Approach

Abstract Internet of Things (IoT) jobs not only require computational resources but also are delay-sensitive and security-sensitive. Edge computing emerges as a promising paradigm to improve the quality of experience for IoT users. Edge computing faces many security threats, perhaps even more than traditional data centers. With a growing amount of data offloaded to Edge Data Centers (EDCs), the EDC performance needs to be considered and evaluated carefully for improving the vulnerable EDC resource utilization while satisfying IoT job requirements. This paper develops an analytical model, which can capture the dynamics of an EDC system with the following features: (i) The system is under heterogeneous workloads; (ii) the system is subject to attacks, which prevent equipment units in the system from providing service and (iii) the jobs in the system are delay-sensitive. Namely, the job processing fails before the processing is completed. Based on the proposed model, we develop formulas for performance and profit metrics and conduct a series of simulation experiments to verify the correctness and accuracy of our model. Finally, through our model, we evaluate the performance of the EDC, and we offer solutions for EDC administrators to maximize profit.