Supply Unit Research Articles

Perancangan Pintu Ruang Start Arena Pacuan Kuda Menggunakan Sistem Pneumatik

Starting gate door is a tool used horse racing arena that serves as a star or space to take off before darting run to racetrack. Doors starting gate consists of a variety of forms and working method, from the manual to which use the automatic system, such as; mechanical, hydraulic, electric and pneumatic systems. Starting gate door with pneumatic system is a tool that is used to open and close starting gate door, the way it works is that a pneumatic cylinder is installed on the door, then pneumatic system functions to open and close the door. Pneumatic system is a tool that uses air as an energy source, components required in the pneumatic system: compressor or air supply unit, or air processing unit (Filter, regulator, and lubrication), regulator or valve unit and the main thing is the pneumatic cylinder serves as a tool which converts compressed air energy into mechanical energy (linear motion of the cylinder rod). In this study aims to be able to get the shape of the starting gate door using a pneumatic system, which can be used as a reference in making the actual door, so that in its application on the racetrack it can be used easily and the time it takes to release the horse becomes faster and the time it takes to release the horse becomes faster. From design results, it is known load that will work on the pneumatic cylinder is 4703.5 N, the inner diameter 100 mm, diameter cylinder rod is 25 mm, total air consumption required is 4,6 liter, compressor discharge is 0,39 liter/second, and compressor power is 0,5 HP.

Development of an Intelligent Based Water Pipelines Damage Control System at the Supply Unit of the Federal Polytechnic Offa, Kwara State

Water is the most valuable means of life sustainability because it is a basic need of all households. The incessant water leakage levels in the water supply network on the mini campus, Federal Polytechnic Offa, is one of the most vital issues to address by the work unit on the School campus. Works unit provides services to all departments on campus, covering an area of the landmass of 1050 hectares with a population of staff and students of approximately 13 000. The work unit is in charge of correctional facilities and operation. The sub-service of the work unit on water supply system comprising a network of 1km of water pipes and 1500 litres capacity storage tower across units. The input system volume in the lose of water supply is approximately 56%, from which a significant proportion is about physical losses. This paper focused on intelligent-based leakage control to replace the traditional method used on campus parameters for backtesting tracing when physical damage becomes visible. However, the result of the study revolves around the design and implementation of a prototype system. The study created a management console as an intelligent decision support system. The realism of the study summarizes various operations by developing intelligent reporting software with data warehouse techniques to facilitate underground leak line pipes tracking.

Feedback Linearization Based Flow Rate Control for Centrifugal Pump in Coupled-Tank Water Meter Testing System

A permanent magnet direct current (PMDC) motor centrifugal pump is intended to be used as the water supply unit in a feedback linearization based coupled-tank water meter testing system. Flow rate generated by the pump corresponds to the input variable for implementing the input-output feedback linearization to this single-input-single-output (SISO) system. The pump motor is driven by an Arm Cortex M7 based microcontroller applying the pulse-width modulation (PWM) strategy at various frequencies and pwm methods. It is aimed to determine a suitable PWM frequency and driving method in order to provide a stable flow rate at the desired duty cycle values. An H-Bridge driver integrated circuit (L298N) is used in both fast decay and slow decay modes for driving the pump motor. Flow rate measurements are carried out at 4 range of frequencies between 100 Hz and 20 kHz for each mode. Fast decay mode in low pwm frequency (100Hz) results in higher deviations at the steady-state flow rate. However, slow decay mode provides a faster reduction in motor speed despite the slower current decay, which improves the flow rate stability and minimize deviations at constant pwm duty cycle values. High pwm switching frequencies increase the energy losses resulting in a lower driving voltage range, which reduces the effective range of selection for pwm duty cycle setting of flow rate adjustment. 1 kHz PWM frequency combined with the slow-decay driving mode achieves good performance in terms of linear regression and wider range for pwm duty cycle to flow rate transformation.

A Comprehensive Approach for an Approximative Integration of Nonlinear-Bivariate Functions in Mixed-Integer Linear Programming Models

As decentralized energy supply units, microgrids can make a decisive contribution to achieving climate targets. In this context, it is particularly important to determine the optimal size of the energy components contained in the microgrids and their optimal operating schedule. Hence, mathematical optimization methods are often used in association with such tasks. In particular, mixed-integer linear programming (MILP) has proven to be a useful tool. Due to the versatility of the different energetic components (e.g., storages, solar modules) and their special technical characteristics, linear relationships can often only inadequately describe the real processes. In order to take advantage of linear solution techniques but at the same time better represent these real-world processes, accurate and efficient approximation techniques need to be applied in system modeling. In particular, nonlinear-bivariate functions represent a major challenge, which is why this paper derives and implements a method that addresses this issue. The advantage of this method is that any bivariate mixed-integer nonlinear programming (MINLP) formulation can be transformed into a MILP formulation using this comprehensive method. For a performance comparison, a mixed-integer quadratic constrained programming (MIQCP) model—as an MINLP special case—is applied and transformed into a MILP, and the solution of the transformed problem is compared with the one of the MIQCP. Since there are good off-the-shelf solvers for MIQCP problems available, the comparison is conservative. The results for an exemplary microgrid sizing task show that the method delivers a strong performance, both in terms of approximation error (0.08%) and computation time. The method and its implementation can serve as a general user-tool but also as a basis for further methodological developments and research.

Quality assessment of young of the hybrids “Lensky sturgeon × Russian sturgeon” and “bester” grown in a circulated water supply unit

The actual direction of modern aquaculture is the optimization of fish breeding processes by monitoring and managing environmental parameters and feeding regimes, reducing the influence of seasonality on technological processes in order to increase the yield of marketable products per unit area. The most optimal option for such industrial aquaculture is the use of recirculating water supply systems, which have proven themselves especially well in the cultivation of sturgeon fish. In commercial aquaculture, aimed at year-round production of high-value delicacy products in the form of meat and caviar, hybrid forms of sturgeon are becoming more common. The article describes the experience of growing juvenile hybrids Lensky sturgeon × Russian sturgeon and Bester in the pools installed in the recirculating water installation of Caspian Bekiresy Limited (Atyrau, Kazakhstan) is described. The article presents the results of monitoring the hydrochemical parameters of water, as well as the characteristics of the types of feed used in the cultivation of sturgeon hybrids at different stages of ontogenesis. The indicators of the initial and final weight, as well as the values of the absolute, average daily and relative growth of the yearlings of sturgeon hybrids were determined. A comparative assessment of the survival of sturgeon hybrid fry when grown in a recirculating water installation pools using water from an artesian well was carried out. The experience of growing sturgeon interspecific hybrids, based on the obtained fish-biological indicators, allows us to recommend them as a full-fledged replacement for parental species, the cultivation of which under artificial conditions has a low efficiency. Moreover, bester, which had high rates of growth and survival, is a more promising object for large-scale commercial cultivation in conditions of recirculating water supply installations.

Designing transformer oil immersion cooling servers for machine learning and first principle calculations.

A transfomer oil immersion cooling server is designed and constructed for machine learning applications and first principle calculations that are carried out for materials-related research. CPU, motherboard, random access memory, hard disk drive, solid state drive, graphic card, and the power supply unit are submerged into the transformer oil in order to cool the entire system. Benchmark tests reveal that overall performance is improved while performance times for multicore calculations are dramatically improved. Furthermore, calculation times for machine learning with large data sets and density functional theory calculations are shortened during single core calculations. Thus, a transformer oil immersion cooling server is proposed to be an alternative cooling system used for improving the performance of first principle calculations and machine learning.

A novel energy management framework incorporating multi‐carrier energy hub for smart city

The development of advanced and intelligent measurement instruments in recent years has increased the intelligence of modern energy systems, especially power systems. Besides, with the advancement of energy conversion technologies, these systems benefit from multi-carrier energy resources. Accordingly, this paper presents a model of smart city which considers various components, including smart transportation system (STS), microgrid (MG), and smart energy hub (SEH) with the ability of energy transformation. The proposed model addresses the islanded operation of a smart city that makes it a smart island. This island deploys the energy carriers of electricity, heat, gas and water as well. In addition, STS includes electric vehicle (EV) parking lots as well as metro system (MS) that can interactively exchange energy. More precisely, the different components of the smart island are modelled on the assumption of energy interdependency. In the proposed model, the water supply unit in SEH is provided which can be effective in reducing the cost of components by supplying water to them. In order to exchange energy within STS, metro stations have been optimally allocated using intelligent water drops (IWD) optimization method. In addition to smart island modelling, this paper quantifies the uncertainties within STS and MG using cloud theory. Eventually, the proposed model is simulated to ensure its effectiveness and accuracy.

Modernization and Ways to Improve Reliability of Oil Supply to Steam Turbine Units for DPM-2

Russia has announced a DPM-2 programme to modernize old power plant equipment. One of the main areas of modernization is the replacement of some of the equipment while maintaining the foundations, building structures, most of the equipment and piping of the turbine unit. It is common practice to introduce additional equipment, such as control and protection units for electro-hydraulic control systems, as well as new pipework, which leads to problems in the layout of the steam turbine unit.The oil system is an integral part of the turbine unit. It accounts for a significant proportion of the cell volume of the steam turbine unit layout. This property of the system can be used to solve problems associated with the layout of a steam turbine unit in modernizations. A solution is proposed for redesigned layout of the oil system in the cell by introducing an oil supply module (station) into the structure of the steam turbine unit. As of now, there are no commercially available offers of an oil station with the required oil tank capacity. The oil station module is arranged at places free from equipment of the cell, for example, at the 0.000 elevation or under the upper operating mark near the generator and below the level of turbine unit bearings to enable oil drainage by gravity. The main differences are outlined between the proposed oil station and the existing oil system.The oil system determines the reliable and trouble-free operation of the steam turbine unit. In order to be able to introduce an oil supply module into operation it is necessary to design the system based on the requirement of maximum reliability. Reliability analysis of oil supply unit has been carried out. The regularities between the designer's decisions and the reliability of the resulting system are revealed. The influence is considered of the oil station components on individual reliability constituents: survivability, durability, fail-safety, maintainability, fire safety.

Intensification of the Process of Drying Fruits and Vegetables in a Recirculating Solar Dryer

To intensify the drying process and refine the modes of drying fruits and vegetables, the authors have developed a recirculating solar dryer with a recuperative heat exchanger for drying fruit and vegetable products with a loading capacity of 30 kg for fresh fruit. The solar drying plant contains a drying chamber equipped with a ventilation system, an autonomous power supply unit (solar panel), a control panel and automatic control systems. The recirculating solar dryer works only with solar energy. In this solar dryer, the kinetics of fruit drying was studied in the drying agent recirculation mode with and without a heat exchanger. It has been established that in the recirculation mode, the drying time of fruits is reduced by 1.5-2 times compared to that in a conventional solar dryer.

Highly Transparent and Flexible Zn-Ti3C2Tx MXene Hybrid Capacitors.

With the development of transparent and wearable electronic devices, energy supply units with high transmittance and flexibility, long cycle life, and high power and energy density are urgently needed. Zinc ion hybrid capacitors (ZIHCs) combined with the advantages of both supercapacitors and zinc ion batteries are promising energy supply components in the abovementioned devices. In addition, the preparation of multifunctional devices has become a trend for the need of space- and resource-saving. Therefore, obtaining ZIHCs with high transmittance and exploring their potential applications are meaningful challenges. Herein, a transparent and flexible ZIHC composed of a patterned zinc foil anode, transparent MXene cathode, and ZnSO4-polyacrylamide (PAM) hydrogel electrolyte is designed and realized. The ZIHC exhibits a superior capacitance of 318 μF cm-2 (5 mV s-1) with 94% transmittance and retains 76% of the initial capacitance after 10,000 charge-discharge cycles. It also shows excellent flexibility, i.e., its capacitance has no obvious attenuation under different bending states. Interestingly, the leakage current of the ZIHC is highly sensitive to electric fields, which shows potential application in electric field detection. This work presents a method to realize the multifunctional ZIHC with electric field sensing function for transparent and flexible wearable devices in the future.

Electromechanical system of turbomechanism when using an alternative source of electric energy

Purpose. Development of a water supply unit in the conditions of pressure control fed from a renewable source of electric energy with static compensator (STATCOM). Methodology. The research was carried out by the method of mathematical modeling in the application packages MATLAB SimPowerSystems and Simulink. The object of the study is a turbomechanism control system, which is powered by a wind turbine when regulating the voltage and realizes the pressure stabilization during the daily cycle of hydraulic resistance variations. The subject of the study is the structure development of a given level of pressure stabilization in the water supply unit. Findings. A mathematical model of a water supply control system powered by a wind turbine is presented. The unit tests the pressure at a given level in accordance with technological requirements. The nature of the variation in pump performance within the daily cycle of consumption when powered by a wind turbine, which in turn performs regulation using a static compensator, is studied. Originality. The system regulates the generated voltage by using a STATCOM, which allows you to maintain its level constant regardless of changes in the network hydraulic resistance. Practical value. Today, the use of alternative energy sources is becoming increasingly important. The developed conception will allow improving the existing water supply systems and designing new ones. It allows you to adjust the set level of pressure stabilization, while the output of generator is maintained constant under constant wind conditions.

Betavoltaic battery prepared by using polycrystalline CdTe as absorption layer

Betavoltaic microbattery is the main energy supply unit in MEMS, which has the advantages of stable performance, long service life, high energy density and small scale. The current paper presented a design scheme of betavoltaic microbattery with semiconductor material polycrystalline CdTe and 3H radioactive source. In this paper, the properties of polycrystalline CdTe films with different thicknesses and the performance of corresponding devices were tested. In the proposed design scheme, an average energy of 5.7 keV was deposited in the polycrystalline CdTe. The short circuit current density and open circuit voltage of a single device were 5.53 nA/cm2 and 111.2 mV respectively when the thickness of polycrystalline CdTe film was 400 nm.

Internet of Things (IoT) Utilization to Improve Performance and Productivity of Internal Supply Chain

The inevitable transformations brought about by the rapidly changing Internet of Things (IoT) impact all aspects of life today, including management and businesses. Specifically, areas of businesses depending mainly on internal supply chain capacity are experiencing a paradigm shift to ensure effective company performance regarding purchases, production, company sales, and product distribution. This shift means that challenges faced by the internal chain supply unit can be solved by adopting and adapting IoT as a new way to minimize work delays and save time. Moreover, IoT automatically leads to performance and productivity increases. Therefore, the present paper aims to justify adopting and adapting IoT applications in Indonesian companies, including retail businesses. Most companies’ internal supply chain units face several difficulties during and after the devastating peak of COVID-19, which has led to a total global lockdown. These problems' complexity is exponential and requires innovative ways to solve their prevailing challenges. This study used observation, interview, and documentary research methods through a large-scale survey. The survey obtained the necessary information regarding how companies utilize IoT to improve their performance and productivity without hindering their internal supply chain and production units. The study concluded that the adoption of IoT, if well implemented, leads to a sustainable company and uninterrupted supply chain performance, indicating the proper performance of the organization. Doi: 10.28991/esj-2021-SP1-017 Full Text: PDF

Parametric investigations on LCC1 based hydrogen storage system intended for fuel cell applications

Considering the necessity for compact hydrogen storage system for fuel cell stacks, 41 embedded cooling tube (ECT) reactor with an outer cooling jacket (OCJ) is designed, fabricated and tested with 3.75 kg of LCC1® alloy. To analyse the sensitivity of the system performance at various operating conditions and the applicability of this prototype as storage system, an extensive parametric investigation was carried out at varying supply pressure (Ps), absorption temperature (Ta) and desorption temperature (Td). LCC1® alloy achieved maximum hydrogen storage capacity (HSC) of 1.6 wt% within 420 s at Ps of 25 bar, Ta of 25 °C and heat transfer fluid (HTF) flow rate (HTFa) of 6 LPM. Supply pressure is found to have greater influence than absorption temperature over absorption performance and heating output. With Ta of 25 °C, HTFa of 6 LPM, HSC of 1.58 wt% and 1.6 wt% were achieved at Ps of 20 bar and 30 bar, respectively, resulting in corresponding specific heating power (SHP) of 497.7 W/kg and 544.9 W/kg. Varying Ta from 25 °C to 35 °C at Ps of 20 bar and HTFa of 6 LPM resulted in 3% reduction in HSC. During desorption, desorption temperature of above 20 °C is found to be favourable with more than 95% of stored hydrogen being desorbed. It is further observed that the dehydriding rate of LCC1® was nearly steady which is potentially suitable for fuel cell applications, as the average dehydriding rate is estimated to be about 15.75 NLPM and 22.91 NLPM at Td of 20 °C and 25 °C, respectively, with 6 LPM of HTF flow rate. The analysed module is proposed as a potential hydrogen supply unit for a 1 kW fuel cell reported in literature.

Test bench for the assessment of vibrations occurring in motorcycles

The purpose of this publication is to present the construction and adaptation of the test stand intended for motorcycle simulation research. The stand is designed to study the impact of motorcycle vibrations that act on the body of the driver and passenger. Motorcycles belong to one of the types of transport that directly affects users. Excessive vibrations transmitted to the body of the driver and passenger can make driving uncomfortable and even dangerous. The vibrations of motorcycles depend mainly on the technical condition of the vehicle, the structure of the vehicle, and the construction of the engine. The stand was built on the basis of a hydraulic power supply unit, distributor, and electrohydraulic pulsators. The purpose of the construction of the stand is to examine a given group of motorcycles to learn and eliminate vibrations that occur in various areas of motorcycles and affect the comfort, health, and safety of motorcycle travelers. Test studies of the presented stand are presented in this article. The preliminary results of the simulation tests determined the possibility of testing individual elements and motorcycles on the laboratory stand.

Low-Temperature NO <sub>x</sub> Reduction by H <sub>2</sub> in Diesel Engine Exhaust

<div class="section abstract"><div class="htmlview paragraph">For the NO<sub>x</sub> removal from diesel exhaust, the selective catalytic reduction (SCR) and lean NO<sub>x</sub> traps are established technologies. However, these procedures lack efficiency below 200 °C, which is of importance for city driving and cold start phases. Thus, the present paper deals with the development of a novel low-temperature deNO<sub>x</sub> strategy implying the catalytic NO<sub>x</sub> reduction by hydrogen. For the investigations, a highly active H<sub>2</sub>-deNO<sub>x</sub> catalyst, originally engineered for lean H<sub>2</sub> combustion engines, was employed. This Pt-based catalyst reached peak NO<sub>x</sub> conversion of 95 % in synthetic diesel exhaust with N<sub>2</sub> selectivities up to 80 %. Additionally, driving cycle tests on a diesel engine test bench were also performed to evaluate the H<sub>2</sub>-deNO<sub>x</sub> performance under practical conditions. For this purpose, a diesel oxidation catalyst, a diesel particulate filter and a H<sub>2</sub> injection nozzle with mixing unit were placed upstream to the full size H<sub>2</sub>-deNO<sub>x</sub> catalyst. As a result, the Worldwide harmonized Light vehicles Test Cycle (WLTC), urban cycle segment of the Common Artemis Driving Cycle (CADC UC) and Transport for London Urban Inter Peak (TfL UIP) driving cycle revealed NO<sub>x</sub> conversions up to 90 % at temperatures as low as 80 °C. However, outside the low-temperature region, H<sub>2</sub>-deNO<sub>x</sub> activity dropped significantly evidencing the need for an additional underfloor SCR system. Moreover, slight N<sub>2</sub>O formation was observed in the engine tests making further catalyst development necessary, since N<sub>2</sub>O is considered a critical component due to its global warming potential. Additionally, the H<sub>2</sub> demand for low-temperature deNO<sub>x</sub> in diesel passenger cars was estimated and a novel on-board H<sub>2</sub> production strategy based on DEF electrolysis was developed. This method provided both H<sub>2</sub> as well as gaseous NH<sub>3</sub>. Subsequent simulations of H<sub>2</sub> production demonstrate small size factors (≤ 525 cm<sup>3</sup>) and rather low energy consumption of the H<sub>2</sub> supply unit, e.g. 0.25 kWh for the TfL UIP driving cycle.</div></div>

Optimal energy management of multi-carrier networked energy hubs considering efficient integration of demand response and electrical vehicles: A cooperative energy management framework

This paper presents a cooperative energy management approach for multi-carrier networked energy hubs. The proposed scheme facilitates energy hubs to exchange power for higher economic and environmental benefits. Based on the cooperative game theory, individual energy hubs cooperate to secure maximum profit, which is then fairly distributed among the hubs to ensure the economic stability of the coalition. The proposed model considers the networked system in which hubs are integrated with multi-energy resources such as electrical and natural gas supply, renewable sources, combined heat and power units (CHPs), gas boilers, electrical and thermal energy storage units to satisfy electrical and thermal demands. A scenario-based generation and reduction algorithm is employed to address the uncertain behaviour of sources. Moreover, a price-based demand response program (DR) and electrical vehicles (EVs) are integrated to make the network more flexible. To analyse the proposed cooperative energy management, the system is modelled as a mixed-integer linear programming problem. Results show that operating costs and greenhouse gas (GHG) emissions are reduced and the self-reliability of the networked system improves. With cooperation and flexible resources, the coalition achieves its maximum profit, which is fairly and stably distributed among the hubs by using Shapley value.

A 10 MW class data center with ultra-dense high-efficiency energy distribution: Design and economic evaluation of superconducting DC busbar networks

With the rapid global developments of digital economy and internet-based technologies, the ultra-dense high-efficiency energy distribution and supply are becoming urgently essential for the data centers that contain large amounts of information-technology (IT) equipments. Considering the limitation of current-carrying capacity and huge ohmic loss of the conventional copper busbars, this paper presents a novel solution using high-temperature superconductor (HTS) DC busbars for data centers with the ultra-high current-carrying capacity and compact size. The full layouts of 3-grade HTS busbars are designed in accord with the industrial standards of date centers. The economic analysis on different busbar schemes for a 10 MW class data center is carried out. For the 100 V/100 kA scheme, the ratio of total operating cost (HTS busbars/copper busbars) can be down to 0.11. With the consideration of the power supply unit (PSU) conversion efficiency, the benefit-turnover period can be reduced from approximately 23 to 17 years. A general design guideline (technical design and economic analysis) is made for building HTS busbar networks in high-dense data centers. Overall, the novel design, technical evaluation and economic analysis of the superconducting DC busbar network can provide useful information and potential solutions for the future high-dense data centers.

Lab-on-cloth integrated with a photoelectrochemical cell and ion imprinting for point-of-care testing of Hg(Ⅱ)

In this work, we successfully developed a cloth-based device integrated with a photoelectrochemical (PEC) cell and ion imprinting for point-of-care testing (POCT) of divalent mercury ions (Hg(Ⅱ)). PEC cells have increasingly emerged as promising power supply units in recent years. The CdS/ZnS core-shell quantum dots (QDs) are used in the PEC cell, because they improve the spatial separation and transfer of charge and broaden the absorption of visible light. Ion imprinting can identify a specific metal ion selectively in the presence of other interfering ions. To achieve noninterference identification, the QDs-based PEC cell region is isolated from the ion imprinting-based detection area. In addition, wax screen-printing can be used in conjunction with carbon ink screen-printing for economical and facile fabrication of cloth-based devices. Under optimized conditions, Hg(Ⅱ) can be determined over the range of 0.0005–5 mg/L, with a detection limit of 0.090 µg/L (i.e., 0.45 nM). The proposed cloth-based devices are also applied successfully for the detection of Hg(Ⅱ) in sweat, complex water and food samples, with recoveries of 98.2–116.1% and relative standard deviations (RSDs) of 1.2–13.9%. Additionally, cloth-based devices have acceptable storage stability and selectivity. Therefore, the presented method offers a sensitive, low-cost, portable POCT device and has the potential to be applied for human body, environmental and food monitoring in remote areas and developing or industrialized countries.

Improvements in Financing Could Increase the Single-Family Affordable Housing Supply

The United States faces a shortage of housing supply, estimated to be millions of units. This shortage is especially acute in the affordable sector. Although the causes of the supply shortage are many, we focus on one major set of constraints: financing. In particular, we focus on how to improve financing for the three types of affordable single-family housing where we see the most potential: manufactured housing (MH), accessory dwelling units (ADUs), and housing preservation. We argue that these financing issues constrain production; improving financing will grow consumer demand for affordable housing and preservation and prompt builders and manufacturers to respond by increasing supply. Finally, we try to quantify the potential impact in each of these areas to increase housing supply. Overcoming these financing hurdles would remove a major roadblock facing MH, ADU, and housing preservation and allow for the addition of a significant number of units of affordable housing supply.