Installation Of Devices Research Articles

Physics-enhanced machine learning-based optimization of tuned mass damper parameters for seismically-excited buildings

Optimal design of tuned mass damper (TMD) parameters should be implemented before device installation to achieve the desired vibration reduction effects for tall and quite slender buildings. Although various optimization algorithms have been developed for searching TMD parameters, there has been very limited exploration of machine learning-based optimization approach in this domain. In this paper, two machine learning-based algorithms are proposed to optimize the natural frequency and damping ratio of a TMD device for seismically excited building. The first algorithm investigates the single-objective optimization of a TMD parameters on a linear building structure. It is based on physics-enhanced generative and adversarial network (GAN) architecture. A generative network randomly generates the primary TMD parameters within the specified parameter ranges, while an adversarial network guides the evolution of parameters to acquire updated parameters, a physical evaluation network assesses the performance of the updated and primary parameters, subsequently providing training data for both the generated network and adversarial network. Furthermore, a second physics-enhanced machine learning algorithm is proposed for the multi-objective optimization of a TMD parameters on a nonlinear building structure under various seismic excitations. The physical evaluation network is extended to consider multiple objective functions, in which the multiple objective functions are integrated through a kind of decomposition scheme, i.e., weighted sum approach. Then, a better set of parameters can be determined and a Pareto optimal solution is obtained. To verify the effectiveness of the two proposed algorithms, single-objective optimization of a TMD parameters for a linear shear-type structure under seismic excitation and a multiple-objectives optimization of a TMD parameters for a seismically excited nonlinear moment-resisting frame (MRF) are conducted and the optimizations are validated by comparing with those by the conventional particle swarm optimization (PSO) approach.

Analysis of operation modes of shunting diesel locomotives when performing shunting work

An overview of modern trends in updating shunting locomotives, which are based on the installation of on-board energy storage devices, multi-diesel propulsion power plants, and power plants operated on hydrogen energy sources, was carried out. The necessity to take into account the operating conditions of a shunting diesel locomotive when choosing an upgrade option is shown. The operation modes of shunting diesel locomotives during shunting operations at the Козятин-I freight station during three shifts were considered. By analyzing the data of the БІС-Р onboard system and processing the route sheets, the parameters of the operating modes were determined. Calculations of diesel engine power utilization indicators were performed, according to which it was determined that the full use of the installed diesel generator power is 7.5...8.4%, and the maximum diesel power recorded under the studied operating conditions is about 50%. The duration of work with traction loads is 49.5...68.8% of the shift time. The longest - 55...60% of the total duration of work under traction - are modes with a power of 0...50 kW. The duration of work without load is 18.1...36.9% of the duration of the shift. The shunting work performed is related to the formation and disassembly of trains, including the use of a sorting slide, as a result of which the traction power transmission operates with a low efficiency. In order to reduce the consumption of fuel and energy resources when performing shunting work, it is necessary to update the fleet of locomotives for shunting work, the characteristics of which are adapted to the operating modes. Key words: hybrid locomotive, modernization, shunting, energy efficiency, energy storage

Adaptive Dynamic Droop Control for Photovoltaic-Rich Distribution Networks Considering Photovoltaic Uncertainties

ABSTRACT The integration of photovoltaic (PV) units into distribution networks is becoming crucial as renewable energy sources gain more prominence. However, the intermittent nature of solar energy causes voltage fluctuations and power losses that need to be addressed. To address these challenges associated with integrating PV units into distribution networks, a novel approach is proposed that provides reactive power ancillary support using a decentralized local dynamic droop control (DDC) strategy. The proposed approach, combined with a meta-heuristic reptile search algorithm (RSA) technique that identifies the appropriate sizing and placement of multiple PV arrays in distribution networks, will substantially improve the voltage profile and full utilization of the PV inverter’s capacity to provide reactive power support over a 24-hour period. The PV systems are modeled using the Lambert-W function, which simplifies the estimation of PV at its maximum power point (MPP) without resorting to computationally intensive MPP tracking techniques. The study leverages 24 hours of realistic data, including ambient temperature and solar irradiance, together with the inverter’s terminal voltage, to estimate the amount of reactive power an inverter can handle. The proposed method substantially improves the voltage profile with full utilization of the PV inverter’s capacity to provide reactive power support over a 24-hour period. The study demonstrates that this approach prioritizes a decentralized network and PV inverters over a centralized management system, making it a promising option for future PV systems that require improved grid compatibility and integration without the installation of additional reactive power devices. In addition, a customized performance index based on the integral square of the voltages at various buses where PVs are located in IEEE-33 and IEEE-69 test bus systems, summed over a 24-hour time window, was calculated for comparative analysis. The proposed method results in an improvement of 93.9% and 95.6% over the base case test systems, whereas conventional droop control results in an improvement of 33.47% and 30.9% only over the base case, respectively, for the test systems.

Integrated Acetic Acid Visual Inspection with Installation or Examination of Intrauterine Contraception Devices: Literature Review

Cervical cancer is one of the post-translational modification where the incidence has continued to increase in the past 10 years. Cervical cancer screening using a single visit approach (SVA) model for prevention of cervical cancer through an isovaleric acidemia (IVA) examination followed by cryotherapy treatment or referral to a higher service. The SVA approach model is still not effective for increasing cervical cancer screening coverage. The one shot method is an IVA model development design that is integrated with IUD insertion. Based on experience, an IVA examination can be carried out simultaneously with pre-insertion, installation, and post-insertion IUD services. The one shot method for IUD acceptors can provide two benefits in one service and can be done at first-level health facilities.

Economic analysis of heat pump exploitation – A case study

The main aim of the paper is the economic analysis and the assessment of the payback time of the heat pump cooperating with a photovoltaic installation in one of the single-family houses in Poland. The inhabitants consumed 11633 kWh of energy during the year. The heat pump consumed 64.23% of total energy used by inhabitants. The photovoltaic panels generated the electricity of 7728.9 kWh. Profitability of the investment was demonstrated based on analysis of its expenditure and operating costs. The payback time of a heat pump including various financing sources, such as: 100% of one's own contribution, loan for the installation of device using renewable energy sources, the subsidy “My Electricity” and the thermo-modernization allowance was analyzed. The analysis showed that the shortest payback time for this investment using “One's own contribution + subsidy My Electricity + thermo modernization relief” is 11 years and 6 months.

Evolutionary Computation-Based Active Mass Damper Implementation for Vibration Mitigation in Slender Structures Using a Low-Cost Processor

This work is devoted to design, implement and validate an active mass damper (AMD) for vibration mitigation in slender structures. The control law, defined by means of genetic algorithm optimization, is deployed on a low-cost processor (NI myRIO-1900), and experimentally validated on a 13.5-m lively timber footbridge. As is known, problems arising from human-induced vibrations in slender, lightweight and low-damped structures usually require the installation of mechanical devices, such as an AMD, in order to be mitigated. This kind of device tends to reduce the movement of the structure, which can be potentially large when it is subjected to dynamic loads whose main components match its natural frequencies. In those conditions, the AMD is sought to improve the comfort and fulfil the serviceability conditions for the pedestrian use according to some design guides. After the dynamic identification of the actuator, the procedure consisted of the experimental characterization and identification of the modal properties of the structure (natural frequencies and damping ratios). Once the equivalent state space system of the structure is obtained, the design of the control law is developed, based on state feedback, which was deployed in the low-cost controller. Finally, experimental adjustments (filters, gains, etc.) were implemented and the validation test was carried out. The system performance has been evaluated using different metrics, both in the frequency and time domain, and under different loads scenarios, including pedestrian transits to demonstrate the feasibility, robustness and good performance of the proposed system. The strengths of the presented work reside in: (1) the use of genetic evolutionary algorithms to optimize both the state estimator gain and the feedback gain that commands the actuator, whose performance is further tested and analyzed using different fitness functions related to both time and frequency domains and (2) the implementation of the active control system in a low-cost processor, which represents a significant advantage when it comes to implement this system in a real structure.

Necessity investigation of tie-down devices for single-pylon cable-stayed bridges to resist near-fault earthquakes with finite element models updated by vibration measurements

This paper aims to thoroughly investigate the necessity of designing tie-down devices at the boundaries of cable-stayed bridges to sustain near-fault earthquakes. The medium-span Chi-Lu Bridge, the long-span Kao-Pin-Hsi Bridge and the low-pylon Ma-Zu Bridge are chosen for a broad coverage. The finite element models for these three bridges are first updated with ambient vibration measurements and then modified by considering the compression-only feature of bearings to suit for seismic analyses. For Chi-Lu Bridge, the possibility of its deck to vertically jump out of the shear keys at the girder-pier connection under an exceptional near-fault earthquake is explicitly verified. The subsequent lateral swung of deck end in this case is further found to reach a significant level that can easily induce the damages near the pylon-deck intersection observed in the Chi-Chi earthquake. Therefore, the installation of tie-down devices is suggested for a medium-span cable-stayed bridge like Chi-Lu Bridge. In the case of Kao-Pin-Hsi Bridge, the analyzed results indicate that the capacity of tie-down devices originally designed to limit the uplift movement produced by live loads is not satisfactory to resist near-fault earthquakes. As for Ma-Zu Bridge, the corresponding results demonstrate that the addition of tie-down devices is normally not necessary.

Distribution System State Estimation Using Hybrid Traditional and Advanced Measurements for Grid Modernization

Distribution System State Estimation (DSSE) techniques have been introduced to monitor and control Active Distribution Networks (ADNs). DSSE calculations are commonly performed using both conventional measurements and pseudo-measurements. Conventional measurements are typically asynchronous and have low update rates, thus leading to inaccurate DSSE results for dynamically changing ADNs. Because of this, smart measurement devices, which are synchronous at high frame rates, have recently been introduced to enhance the monitoring and control of ADNs in modern power networks. However, replacing all traditional measurement devices with smart measurements is not feasible over a short time. Thus, an essential part of the grid modernization process is to use both traditional and advanced measurements to improve DSSE results. In this paper, a new method is proposed to hybridize traditional and advanced measurements using an online machine learning model. In this work, we assume that an ADN has been monitored using traditional measurements and the Weighted Least Square (WLS) method to obtain DSSE results, and the voltage magnitude and phase angle at each bus are considered as state vectors. After a period of time, a network is modified by the installation of advanced measurement devices, such as Phasor Measurement Units (PMUs), to facilitate ADN monitoring and control with a desired performance. Our work proposes a method for taking advantage of all available measurements to improve DSSE results. First, a machine-learning-based regression model was trained from DSSE results obtained using only the traditional measurements available before the installation of smart measurement devices. After smart measurement devices were added to the network, the model predicted traditional measurements when those measurements were not available to enable synchronization between the traditional and smart sensors, despite their different refresh rates. We show that the regression model had improved performance under the condition that it continued to be updated regularly as more data were collected from the measurement devices. In this way, the training model became robust and improved the DSSE performance, even in the presence of more Distributed Generations (DGs). The results of the proposed method were compared to traditional measurements incorporated into the DSSE calculation using a sample-and-hold technique. We present the DSSE results in terms of Mean Absolute Error (MAE) and Root Mean Square Error (RMSE) values for all approaches. The effectiveness of the proposed method was validated using two case studies in the presence of DGs: one using a modified IEEE 33-bus distribution system that considered loads and DGs based on a Monte Carlo simulation and the other using a modified IEEE 69-bus system that considered actual data for loads and DGs. The DSSE results illustrate that the proposed method is better than the sample-and-hold method.

Lightning Surge Overvoltage Protection for Low-Voltage Equipment Placed Outdoors in TT System

When a TT system is used for earthing a low-voltage distribution line, the conductive enclosure of the equipment is grounded separately from the system ground for the power line. In such a case, lightning protection depends on the installation of surge protective devices (SPD) on the equipment side. However, in newer systems, a protective earth (PE) line is wired from the power substation for stable operation and connected to the PE line in the outdoor equipment. In this case, the SPD of the distribution board can suppress the overvoltage on the equipment side. In this article, the overvoltage generated between the power and grounded PE lines of the equipment using a vinyl-insulated vinyl-sheathed flat-type cable for a low-voltage distribution line was examined using transient circuit analysis. Then, we demonstrated countermeasures to achieve electric shock and lightning overvoltage protection.

Pendampingan Pembenahan Instalasi Sistem CCTV untuk Masjid Baitul Rohmah Pudak Payung Semarang

Apart from being a place of worship, the mosque has a function to improve community relations in the environment around the mosque in particular. In order to improve community relations, it is necessary to hold several activities involving the community under the auspices of the mosque. In order for community activities to take place, the mosque is equipped with several assets such as electronic devices, sound systems, air conditioning, infaq contacts/charity boxes and some other supporting furniture. So mosque assets need to be maintained in the security aspect. To support the security aspects of the mosque's environment, in this service there will be mentoring and training on the CCTV (Close Circuit Television) system. This service activity is carried out by technicians, mosque congregation and accompanied by a service team, including; needs assessment, field survey, network design and layout, preparation of budget plans and device requirements, device installation and device firmware settings. After being agreed by the team, this service installed 5 camera points to monitor 4 areas, parking area, yard, congregation area and priest area. From the results of this activity, that the installation of cameras at 5 points in accordance with the planned survey results and needs assessment can provide comprehensive monitoring of environmental conditions outside and inside the mosque, so that it can better guarantee security in the mosque and its surroundings.

Enhancing Water Resource Management Efficiency through Smart Technologies: A Case Study in Kashkadarya Region, Uzbekistan

This article presents a comprehensive study on the implementation of "Smart Water" devices in water management facilities in the Kashkadarya region of Uzbekistan. The goals of this initiative were to achieve efficient water control, real-time monitoring, and rapid water management. Through the installation of smart devices, including "Smart Water" devices and "DIVER" devices, water resources were effectively managed, resulting in online water control and significant water resource savings. The automation of large hydrotechnical facilities, such as the Karshi hydroelectric plant, enabled remote management and reduced technical water losses. Additionally, the pilot project on automation, based on solutions provided by the Australian company "Rubicon Water Pty. Ltd," showcased the potential for digitalization and automation in water resources management. The project demonstrated successful outcomes, including increased accuracy in land reclamation assessment, reduced water shortage, enhanced water resource utilization, and significant cost savings. The findings highlight the effectiveness and advantages of smart technologies in water management, underscoring the need for their widespread adoption in addressing water scarcity and sustainable water resource management globally.
 
 
 
 Highlights:
 
 
 
 
 
 Improved Water Control: Implementation of "Smart Water" devices enables real-time monitoring and online water control, enhancing efficient water resource management.
 
 
 Cost Savings and Resource Efficiency: Automation and smart technologies lead to significant water savings, reduced technical losses, and improved water utilization, resulting in economic benefits.
 
 
 Scalable Solutions for Global Water Management: The successful pilot project by "Rubicon Water Pty. Ltd" demonstrates the potential for widespread adoption of smart technologies in addressing water scarcity and promoting sustainable water resource management globally.
 
 
 Keywords: water resources, smart water, efficient technologies, water management, automation.
 
 
 
 
 

A Monte Carlo Assessment of the Effect of Different Ventilation Strategies to Mitigate the COVID-19 Contagion Risk in Educational Buildings

The COVID-19 pandemic outbreak has increased the general awareness of the importance of proper ventilation in the indoor environment to reduce the contagion risk. In particular, attention has been paid to specific categories of buildings, such as schools, due to two factors: (1) high occupancy density and (2) the presence of young and sometimes more susceptible people. Despite the high level of alertness towards the ventilation of classrooms, robust analyses of the effectiveness of the different strategies to mitigate the contagion risk have been difficult to perform. Indeed, the COVID-19 pandemic is still ongoing, and many factors, such as the presence of multiple viral strains, use of facial masks, progression in vaccination, and installation of air purifiers and other sanitization devices, make it difficult to fully quantify the impact of room ventilation by simply analysing available monitoring data. Moreover, mitigation strategies related to ventilation are often dynamic, increasing the complexity of the problem to assess. In this framework, this work proposes a new Monte Carlo method integrated with building performance simulation to evaluate the number of infected occupants under different scenarios, considering also the dynamic boundary conditions. The described approach has been applied to a case study classroom at the Free University of Bozen-Bolzano, Italy, analysing almost 100 different scenarios and discussing the effectiveness of different ventilation strategies traditionally adopted to ensure suitable IAQ according to CO2 concentration limits. Results highlight the importance of combining different solutions (e.g., mixed-mode ventilation and facial masks) to limit the risk for both students and lecturers.

Gaussian mixture models for the optimal sparse sampling of offshore wind resource

Abstract. Wind resource assessment is a crucial step for the development of offshore wind energy. It relies on the installation of measurement devices, whose placement is an open challenge for developers. Indeed, the optimal sensor placement for field reconstruction is an open challenge in the field of sparse sampling. As for the application to offshore wind field reconstruction, no similar study was found, and standard strategies are based on semi-empirical choices. In this paper, a sparse sampling method using a Gaussian mixture model on numerical weather prediction data is developed for offshore wind reconstruction. It is applied to France's main offshore wind energy development areas: Normandy, southern Brittany and the Mediterranean Sea. The study is based on 3 years of Météo-France AROME's data, available through the MeteoNet data set. Using a Gaussian mixture model for data clustering, it leads to optimal sensor locations with regards to wind field reconstruction error. The proposed workflow is described and compared to state-of-the-art methods for sparse sampling. It constitutes a robust yet simple method for the definition of optimal sensor siting for offshore wind field reconstruction. The described method applied to the study area output sensor arrays of respectively seven, four and four sensors for Normandy, southern Brittany and the Mediterranean Sea. Those sensor arrays perform approximately 20 % better than the median Monte Carlo case and more than 30 % better than state-of-the-art methods with regards to wind field reconstruction error.

STUDY OF THE ILLUMINATION AND DEVELOPMENT OF RECOMMENDATIONS FOR ITS IMPROVEMENT

Goal. Investigate the existing methods of lighting rooms of various search purposes, make effective decisions on increasing the energy efficiency of electrical engineering systems of internal education through the implementation of automated education management systems and energy-efficient management algorithms, explain the principles of lighting construction using natural lighting and the application of modern technologies of familiar and modern lighting devices.
 Task. Analysis of existing technical solutions to increase the energy efficiency of the internal lighting system and substantiation of their energy efficiency indicators.Synthesis of the internal lighting control system of the administrative building. Development of algorithms for energy-efficient control of the internal lighting system taking into account external factors.
 The result of the study. The work is devoted to the analysis of lighting methods and devices used today, as well as the search for effective solutions to increase the energy efficiency of the electrical system of internal lighting due to the implementation of an automated lighting control system and energy-efficient control algorithms, an explanation of the principles of lighting construction using natural lighting and modern application technologies conventional and modern lighting devices, as well as methods of improving lighting efficiency using the latest technologies from existing lighting devices. The main attention is paid to the problems of the currently existing methods of artificial lighting of rooms in houses of various purposes, and to the solution of these problems with the most effective and real methods in practical use. This article may be useful for those interested in upgrading existing lighting or building a new lighting system with efficient use of electricity.
 Conclusions and practical significance. In this work, an analysis of existing energy-efficient technical solutions in interior lighting systems was carried out, based on the results of which it can be concluded that it is appropriate to use LED lamps in the lighting system due to their excellent indicators of luminous flux, light output, long service life and affordable price. It was also a source of various energy-saving methods in lighting systems, which can be attributed to: the introduction of half-light, LED lights and fluorescent lamps, the installation of electronic start-up control devices, more efficient use of light output, the introduction of a system of automatic lighting regulation depending on external factors and maintaining efficiency. education system.

A Case Study on Sustainable Production and Use of Compressed Air in European Industrial Sites of Medium-sized

Due to the urgency in climate change, the industry is mobilized to reduce its greenhouse gases. Compressed air represents nearly 10% of electricity used in industry. The research was carried out in an industrial food site in Europe. This research includes a case study and gives a specific approach and methodology to optimize environmental and economic impact of compressed air production and uses in an industrial site. The installation of this case study contains different type of compressed air, dryers, and filters. Each equipment has been subject to specific monitoring and analysis. Several actions have been identified for reducing carbon emissions by 69 tons such as: reduction of the compressed air pressure of the system, isolation of packaging lines when they are not running, implementation of pumps for vacuum generation on packaging lines, installation of smart management device and a heat recovery system. Financial savings are around 44 000 euros, and the average payback is below 3 years.

AHSS—Construction Material Used in Smart Cities

With the level of development of the smart city, there are more and more research sub-areas in which the latest material and technological solutions are used, enabling the proper management and functioning of these cities. On the one hand, the introduced materials and technologies are designed to facilitate the functioning of residents both in the urban space and at home; on the other hand, the implemented solutions strive to be consistent with the principles of sustainable development. As shown in this article, reports on new technical and technological solutions and their positive and negative effects are strongly emphasized in publications on the development of smart cities. The most highlighted materials research in the smart city area concerns smart materials and their characteristics and applications. A research gap in this area is in the presentation of material solutions, particularly materials intended for the load-bearing structures of vehicles (electric vehicles, flying vehicles) or infrastructure elements (buildings, shelters, etc.) designed to increase the durability of the structure while reducing its weight. This paper aims to comprehensively present the most important research areas related to the functioning of smart cities in light of previous research, with particular emphasis on new material solutions used for thin-walled load-bearing structures in smart cities made of AHSS (advanced high-strength steel). These solutions are very essential for smart cities because their use allows for the installation of additional devices, sensors, transmitters, antennas, etc., without increasing the total weight of the structure; they reduce the number of raw materials used for production (lighter and durable thin structures), ensure lower energy consumption (e.g., lighter vehicles), and also increase the passive safety of systems or increase their lifting capacity (e.g., the possibility of transporting more people using transports at the same time; the possibility of designing and arranging, e.g., green gardens on buildings; etc.). AHSS-welded joints are usually characterized by too-low strength in the base material or a tendency to crack. Thus, the research problem is producing a light and durable AHSS structure using welding processes. The research presented in this article concerns the possibility of producing welded joints using the Metal Active Gas (MAG) process. The test methods include the assessment of the quality of joints, such as through visual examination (VT); according to the requirements of PN-EN ISO 17638; magnetic particle testing (MT); according to PN-EN ISO 17638; and the assessment of the selected mechanical properties, such as tensile strength tests, bending tests, and fatigue strength checks. These methods enable the selection of the correct joints, without welding defects. The results have a practical implication; advanced production technology for obtaining AHSS joints can be used in the construction of the load-bearing elements of mobile vehicles or parts of point infrastructure (shelters, bus stops). The obtained joint is characterized by adequate strength for the production of the assumed structures. The originality of the manuscript is the presentation of a new, cheaper, and uncomplicated solution for obtaining an AHSS joint with good mechanical properties. The application of the presented solution also contributes to sustainable development (lower fuel and material consumption use by mobile vehicles) and may contribute to increasing the load capacity of mobile vehicles (the possibility of transporting more people).

Flexural Performance of Removable Deck Slabs with Fixing Device Details

This study presents a new concept for a deck plate and an accompanying application for a slab system that is easy to fix and separate during construction, while ensuring safe construction loads and optimal flexural performance. Finite element analysis (FEA) was used to determine the load on the fixing device’s contact surface and the specimen’s shape. A direct tensile test was then performed using a universal testing machine to evaluate the anchorage performance of the fixing device. The results of this test were used to optimize the details of the fixing device, which were then evaluated for safety against construction loads. The installation interval and method of the fixing device were varied to determine the maximum installation interval, which was within 300 mm. Finally, flexural performance was evaluated based on the details and spacing of the fixing device installation. The results showed that the details and spacing of the fixing device did not have a significant effect on flexural performance, provided that safety against construction loads was secured. This study describes a promising solution for a slab system that is easy to install and separate during construction, while ensuring safety and flexural performance.

Analysis of the Factors Influencing Speed Cushion Effectiveness in the Urban Context: A Case Study Experiment in the City of Bari, Italy

The installation of Traffic-Calming Devices (TCDs) is an extremely valuable countermeasure to prevent vulnerable road users from fatalities in urban contexts. Among all the TCDs, Berlin Speed Cushions (BSCs) seem to be one of the most promising because they reduce speeds but do not affect emergency vehicles. However, previous research on BSCs is limited and lacks some important aspects, such as the analysis of speeds at different distances from the cushion or the investigation of the influence of other context variables. In this study, BSCs of different lengths (2.20 m, 2.70 m, and 3.20 m) were deployed in the City of Bari on three roads belonging to the same area. To overcome the limitations of previous research, speeds were recorded using a laser-speed gun before and after the implementation of BSCs, in different conditions, in order to take into account the effect of the following factors: the time of day, day of the week, and average hourly traffic. An ANOVA analysis was performed, with speed as the dependent variable and the above-reported factors and the test road site (proxy variable for the cushion length) as factors, independently repeated for six distance ranges with respect to the cushion. The results reveal that speed evidently decreases immediately before (down to about 13 km/h) and after the cushion (down to about 12 km/h), time of the day is an important factor (speed decrease is much more evident during the morning than the evening), and the length of the cushion has some influence on speed decrease (the speed decrease is lower for the longest cushion).

A Rotor Ground Fault Protection Method Based on Injection Principle for Variable Speed Pumped Storage Generator-Motor

Three-phase AC excitation is adopted in the variable speed pumped storage generator-motors, which is different from the DC excitation in traditional synchronous generators. The special rotor winding structure makes the existing rotor ground fault protection methods no longer applicable. Therefore, a rotor ground fault protection method for variable speed pumped storage generator-motor is proposed in this paper. Considering that there is no precondition for additional installation of the injection device at the rotor winding neutral point, the rotor ground fault protection scheme is proposed by connecting the injection device through current limiting resistors outside the rotor winding terminals. The key parameters of injection source, band-pass filter, and current limiting resistance are analyzed and calculated. Then, the online calculation methods of grounding resistance and grounding current are proposed based on the injection equivalent circuit. On this basis, the composite protection criterion considering grounding resistance and grounding current is constructed, and the protection outlet mode is clarified. Simulation and experiments verify the effectiveness of the proposed method.

INSTALLATION OF ELECTRONIC DETECTION DEVICES ON PERSONS OF SEXUAL VIOLANCE AGAINST CHILDRENS (PROBLEMATICS AND SOLUTIONS)

Act No. 17 of 2016 pertaining to the PERPU No. 1 of 2016 pertaining to the second amendment to the Law No. 23 of 2002 on Child Protection is being considered as the number of cases of sexual violence against children increases annually. Therefore, it is necessary to increase the penalties for those who sexually assault children. Government Regulation 70 of 2020 regulates using electronic detection devices as a secondary penalty. However, since their enactment until now, there has been no judge's decision determining the other party's liability for the installation of this electronic detection device. This is due to the fact that the regulation itself contains numerous flawed instruments. This study aims to identify the problems and potential solutions associated with installing electronic detection devices on perpetrators of sexual violence against children. This research leads to an examination of normative legal law, with data gathered through document studies. PP 70/2020's rules for the application of the installation of electronic detectors contain a number of flaws with respect to a number of instruments, as revealed by the research results. This issue will then be compared to the regulations of several countries that have implemented it, such as the Netherlands, England, and the United States so that a solution can be found to apply penalties for the installation of electronic detection devices, specifically how to operate the device using GPS technology and the form of the tool in the form of an electronic bracelet attached to the leg of the perpetrator of sexual harassment against children.