On-off Method Research Articles

Modeling and Control of a PEM Fuel Cell Hybrid Energy System Used in a Vehicle with Fuzzy Logic Method

PEM (Proton Exchange Membrane) fuel cells, which are commonly used in vehicles, are critical for sustainable transportation in the future. In this study, it is aimed to en-hance the system efficiency of the PEM fuel cell and provide fuel economy. To achieve this goal, the hybrid energy system with a PEM fuel cell and battery pack is controlled with two different strategies. The first control strategy is designed using Fuzzy Logic (FL), while the other control strategy is designed with the classical on-off method with the 'Relay' block. Power output of the fuel cell is determined depending on the change in the charging state of the battery pack and the power consumed by the electric vehicle in this study. The aim is to provide that the fuel cell operates in a high-efficiency range and can generate enough power when needed. Vehicle and fuel cell modeling were per-formed in Matlab/Simulink environment. NEDC (New European Driving Cycle) and WLTP (Worldwide Harmonized Light Vehicles Test Procedure) driving cycles were considered and fuel cell efficiency and hydrogen consumption were compared at dif-ferent state of charge values of the battery. The analyses were carried out over long dis-tances by repeating the driving cycles. It was observed that fuzzy logic control provid-ed 11.6% less fuel consumption than classic on-off control in NEDC and WLTP driving cycles repeated five times. The values obtained as a result of the study showed that fuzzy logic control is more advantageous to increase the energy efficiency of fuel cells.

A smart oyster mushroom cultivation using automatic fuzzy logic controller

Oyster mushroom cultivation is an eco-friendly, profitable agribusiness because of its nutritious and medicinal value but it is labor-intensive, and it grows in a sensitive environment. It must use an autonomous environment control system to optimize and offer the necessary growing conditions. To optimize the temperature and humidity and consequently maximize mushroom production, a smart mushroom watering, monitoring, and controlling system using fuzzy logic controllers (FLC) have been developed. This study suggests installing an Internet of Things (IoT) node that uses DHT22 sensors, an ESP32 board, and relays to control actuators (sprinkler, cooling fan, humidifier, and heater) in a smart oyster mushroom house. The controller on sensing current temperature and humidity values using the fuzzy logic technique switches on/off the actuators automatically. The data collected at each IoT node is collected and visualized on the ThingSpeak platform. The computed response time for actuators using FLC is compared with that calculated using a simple ON-OFF method. The findings demonstrate that response time calculation using fuzzy logic is significantly accurate and faster than a simple ON-OFF approach. Additionally, the graphs created in live on ThingSpeak, demonstrate that the FLC algorithm is more robust and effective than the simple ON-OFF algorithm.

First Observation of the MeV Gamma-Ray Universe with Bijective Imaging Spectroscopy Using the Electron-tracking Compton Telescope on Board SMILE-2+

MeV gamma-rays provide a unique window for the direct measurement of line emissions from radioisotopes, but observations have made little significant progress since COMPTEL on board the Compton Gamma-ray Observatory (CGRO). To observe celestial objects in this band, we are developing an electron-tracking Compton camera (ETCC) that realizes both bijective imaging spectroscopy and efficient background reduction gleaned from the recoil-electron track information. The energy spectrum of the observation target can then be obtained by a simple ON–OFF method using a correctly defined point-spread function on the celestial sphere. The performance of celestial object observations was validated on the second balloon SMILE-2+ , on which an ETCC with a gaseous electron tracker was installed that had a volume of 30 × 30 × 30 cm3. Gamma-rays from the Crab Nebula were detected with a significance of 4.0σ in the energy range 0.15–2.1 MeV with a live time of 5.1 hr, as expected before launch. Additionally, the light curve clarified an enhancement of gamma-ray events generated in the Galactic center region, indicating that a significant proportion of the final remaining events are cosmic gamma-rays. Independently, the observed intensity and time variation were consistent with the prelaunch estimates except in the Galactic center region. The estimates were based on the total background of extragalactic diffuse, atmospheric, and instrumental gamma-rays after accounting for the variations in the atmospheric depth and rigidity during the level flight. The Crab results and light curve strongly support our understanding of both the detection sensitivity and the background in real observations. This work promises significant advances in MeV gamma-ray astronomy.

Topology Optimization Combined with a Parametric Algorithm for Industrial Synchronous Reluctance Motor Design

In this paper, we propose combining topology optimization with a parametric algorithm (TOCPA) to design an industrial synchronous reluctance motor (SynRM) that satisfies super-premium efficiency (IE4). TOCPA consists of two main processes. An improved niching algorithm is proposed as an existing parametric algorithm, and multiple optimal points were identified quickly and effectively within the design range specified by the user. Existing parametric algorithms lack the ability to find unpredictable new optimal shapes; therefore, topology optimization has been added. TOCPA converges the two optimization methods to compensate for the shortcomings of each and maximizes the advantages. In addition, the boundary surface ON–OFF method is applied to accelerate the topology optimization process. Subsequent ratio-based smoothing techniques smooth out discontinuous interfaces and remove clusters to improve the torque characteristics and reduce the manufacturing difficulty. Finally, the torque ripple was reduced using the skew technique, and mechanical stability was confirmed using a stress analysis. An IE4 industrial SynRM was successfully designed using TOCPA.

Improving the Performance of Heterogeneous Network Systems in Machine Learning-based 5G Mobile Communication System

Mobile traffic, which has increased significantly with the emergence of Fourth generation longterm evolution (4G-LTE) communications and advances in video streaming services, is still currently increasing at an incredible pace. Fifth-generation (5G) mobile communication systems, which were developed to deal with such a drastic increase in mobile traffic, aim to achieve ultra-high-speed data transmission, low latency, and the accommodation of many more connected devices compared to 4G-LTE systems. 5G communication uses high-frequency bandwidth to implement these features, which leads to an inevitable drawback of a high path loss. In order to overcome this disadvantage, small cell technology was developed, and is defined as small, low-power base stations that can extend the network coverage and solve the shadow area problem. Although small cell technology has these advantages, different problems, such as the effects of interference due to the deployment of a large number of small cells and the differences in devices accessing the network, need to be solved. To do so, it is necessary to develop an algorithm for a service method. However, general algorithms have difficulties in responding to the diverse environment of mobile communication systems, such as sudden increase in traffic in certain areas or sudden changes in the mobile population, and machine learning technology has been applied to solve this problem. This study employs a machine learning algorithm to determine small cell connections. In addition, a 5G macro system, the application of small cells, and the application of machine learning algorithms are compared to determine the performance improvement in the machine learning algorithm. Moreover, Support Vector Machine (SVM), Logistic Regression and Decision Tree algorithm are employed to show a training method that uses basic training data and a small cell on-off method, and the performance enhancement is verified based on this method.

Optimal Design of a Synchronous Reluctance Motor Using a Genetic Topology Algorithm

The topology algorithm (TA) can effectively find an optimal solution by changing the material and shape of the design target without the limitation of design variables. In this paper, a genetic topology algorithm (GTA) is proposed for the design optimization of a synchronous reluctance motor (SynRM). By applying the stochastic algorithm (genetic algorithm (GA)) and the deterministic algorithm (ON-OFF method) to the design, the optimal shape can be found quickly and effectively. The GTA, which improves manufacturability by removing the aliasing that occurs in TA, was applied to the design of SynRM to search for the optimal model. After dividing the rotor into a reverse mesh grid, the optimal topology was searched for by GA and ON-OFF methods. Then, mechanical stability was verified through stress analysis, and additional performance improvement was obtained through the skew technique. The final design, which satisfies the minimum efficiency, required torque, and torque ripple was derived by applying the step-by-step design using GTA to the SynRM optimization.

Pengendalian Suhu dan Kelembapan Sistem Aeroponik Tanaman Stroberi Berbasis IOT Menggunakan Fuzzy Logic

Penanaman tanaman stroberi secara konvensional cukup sulit dilakukan karena membutuhkan ruang, tenaga kerja, air, serta lahan yang subur. Karenanya, penanaman tanaman tanpa tanah dapat diterapkan. Sistem aeroponik adalah penanaman menggunakan media udara. Akar tanaman dibiarkan menggantung dan disemprot nutrisi. Keistimewaannya adalah dapat mengurangi konsumsi air, pupuk, dan pemaksimalan lahan. Pada penelitian ini mist nozzle dikendalikan oleh mikrokomputer menggunakan logika Fuzzy untuk menyemprot bagian akar dan tajuk dengan masukan sensor suhu dan kelembapan. Kebutuhan nutrisi akar dikendalikan dengan metode on-off. LED dikendalikan menurut waktu. Kadar pH pada tandon nutrisi dapat diawasi menggunakan sensor pH. Sistem dapat diawasi dan dikendalikan dengan antarmuka pada Android. Hasil penelitian menunjukkan ketercapaian nilai rata-rata kebutuhan suhu akar yakni 23,3℃ dari rentang 18-30℃, dan suhu tajuk 21,5℃ dari rentang 14-25℃. Selain itu, kelembapan akar dan tajuk juga masuk dalam rentang kebutuhan 85-95% yakni 89% dan 93%. Sistem pengawasan dan pengendalian dapat dilakukan dari jarak jauh dengan menggunakan aplikasi Blynk.

Rotor head shape optimization in a salient pole synchronous machine

The purpose of this paper is to optimize the topology of the rotor head in a Salient Pole Synchronous Generator to maximize the magnetic flux in the stator yoke and in the air gap. The generator is modelled using FE method, and the ON-OFF method is used to manage the optimization domain. Genetic Algorithm is used to find the optimal solution for the problem. The resulting topology and convergence graphs are also presented, and the results are discussed.

Development of PID-based furnace temperature control system for zirconium calcination

The calcinator furnace in PSTA-BATAN is currently installed with ON-OFF temperature controller to maintaning temperature changes in calcination process. Calcination is a process of heating a substance at high temperature in stages but still below its melting point to remove its impurities. The ON-OFF temperature controller using a relay as the power switching for AC voltages applied on furnace electric heat element when the temperature exceeds or below the set point temperature. The contactor movement in relay will cause a sudden surge of voltages and currents which could lead to the thermal shock or unstable heating rates and unstable holding time. In this paper, the ON-OFF method was developed into Proportional Integral Derivative (PID)-based which has simple structure and robust performance for phase angle controlling in AC voltages applied on furnace electric heat element to controlling the temperature in multi stages by using Arduino Nano as the microcontroller.

Current Distribution Optimization by Using Genetic-Algorithm Based On-Off Method: Application to Pellet Injection System

Current Distribution Optimization by Using Genetic-Algorithm Based On-Off Method: Application to Pellet Injection System

Evaluating the potential energy landscape over single molecules at room temperature with lateral force microscopy

One of the challenges of AFM, in contrast to STM, is that the measured signal includes both long-range and short-range components. The most accurate method for removing long-range components is to measure both on and off an adsorbate and to subtract the difference. This on-off method is challenging at room temperature due to thermal drift. By moving to a non-contact scheme in which the lateral component of the force interaction is probed, the measurement is dominated by short-range interactions. We use frequency-modulation lateral force microscopy to measure individual PTCDA molecules adsorbed on Ag/Si(111)-(3×3). By fitting the data to a model potential, we can extract the depth and width of the potential. When the tip is closer to the sample, a repulsive feature can be observed in the data.

可変デザイン領域を用いたOn-Off法による回転機のトポロジー最適化

This paper presents topology optimization of rotating machines using the On-Off method with variable design region. The flux barrier shape is optimized by the present method in which the thin design regions covering the boundary of the flux barriers are adaptively modified during the optimization process. Because the design region is strongly restricted, the optimized flux barrier boundaries are expected to be rather smooth even if the smoothing procedure is not employed. Moreover the present method is based on the evolutionary algorithm which has powerful searching abilities. In order to validate its effectiveness, the flux barrier shapes of the interior permanent magnetic motors and synchronous reluctance motors are optimized by the present method. The performance of the present method is shown to be superior over that of the Rosen-brock method.

An empirical study on energy efficiency improvement through photovoltaic systems and a LED lighting control system

In this research, a facility was constructed and its performance was analyzed to improve the energy efficiency of a vertical-type water treatment building. After the design and construction of a fixed tilt Photovoltaic in Building (PVIB) on the rooftop using a crystalline silicon solar cell module and photovoltaic generator integrated with the building by using a Building Integrated Photovoltaic System (BIPV), a thin-film module on the rooftop and outer wall of water treatment building, and the generation efficiency was analyzed. Also, a DC distribution was established for use of a brushless DC (BLDC) pump motor, and the existing lighting-facility-based manual on-off method was turned into a system for energy conservation by controlling light emitting diode (LED) through a wireless motion sensor and dimming control. In addition, a Building Energy Management System (BEMS) for a real-time analysis of the energy efficiency for a vertical0type water treatment building was prepared and tested. The vertical-type water treatment building developed in this study is currently operating the BEMS. The vertical-type water treatment building reported in this paper is expected to reduce energy consumption by about 30% compared to existing water treatment systems.

The Experimental Analysis on the Regularity of Heating Load in Buildings Using Heat Meters with On-Off Time and Area Method in Shijiazhuang Area

Based on the heating load experiment adopting on-off time and area measuring method of typical heat users located in different places of different buildings in Shijiazhuang, the heating loads of the heat users which are summarized as two typical heat using modes are studied in this paper and the heating loads in the whole winter heating season of the building is estimated. The results shows that with the user’s heat adopting ratio in these two modes increases, the corresponding heating load is lower, the heating load distribution curve gets smoothly in the whole heating period and the peak value of the system heating loads reduces. This regularity of heating load distribution is beneficial for enhancing the stability of heating system and the thermal efficiency of the heat source.

Topology Optimization Method Based on On–Off Method and Level Set Approach

This paper proposes a two-step method for topology optimization, in which after global search is performed by the on-off method, and then local search is carried out by the level set approach. The genetic and gradient-based algorithms are employed for the former and latter optimizations, respectively. This present method is applied to two numerical examples; topology optimizations of a magnetic shield system and interior permanent magnetic motor. It is shown that this present method can find solutions with better performances in comparison with the conventional on-off method.

Design Optimization Techniques for Electromagnetic Systems

This paper reports the state-of-the-art of optimization methods based on computational electromagnetism. This paper describes genetic algorithm which has widely been used for optimization of electromagnetic devices and machines, hierarchical voxel finite element method suitable for parameter optimization, single and multi-objective parameter optimizations, topology optimizations using the level-set method coupled with GA-based ON-OFF method, and NGnet-based topology optimization, and robust optimization.

Peripheral neuropathy: a complication of systemic sclerosis

We performed bedside testing for peripheral neuropathy in our systemic sclerosis (SSc) population to determine whether foot care guidelines should be developed for SSc. Twenty consecutive SSc patients and 20 healthy control (HC) patients were evaluated for peripheral neuropathy in both feet using the 10-g Semmes-Weinstein monofilament examination (SWME) and 128 Hz vibration sensation using the on-off method. Independent, blinded, vibratory sensation, and SWME evaluations were performed on each subject by two investigators who had completed a training session to standardize each exam. An additional consecutive 20 patients with type 2 diabetes mellitus (DM) were examined by a diabetologist to compare with peripheral neuropathy prevalence in SSc patients. We examined the inter-rater variability using Cohen's kappa. We compared SWME and vibratory sensation in SSc to HC using Fisher's exact. The t test was used to compare duration of disease and modified Rodnan skin score (mRSS) for those with abnormal SWME or vibratory sensation. Two of 20 SSc patients reported sensory foot symptoms consistent with peripheral neuropathy prior to the examination. Inter-rater agreement for both SWME and vibratory sensation was strong (kappa: 0.72 and 0.83, respectively). Two HC and 12 SSc patients demonstrated abnormal vibratory sense (one-sided Fishers' exact, p < 0.002). No HC and four SSc patients had abnormal monofilament exams (one-sided Fisher's exact, p = 0.053). Neither mRSS (p = 0.28) nor duration of non-Raynauds (p = 0.07) symptoms differed between those with peripheral neuropathy and those without. Duration of Raynaud's symptoms were clinically significantly associated with presence of peripheral neuropathy (p = 0.04). The prevalence of sensory loss to monofilament in SSc was identical to DM patients (4/20). SSc patients have a considerable prevalence of pedal peripheral neuropathy as detected by loss of vibratory sensation or inability to sense the 10-g SWME. Further studies are indicated to determine if routine screening for neuropathy and subsequent podiatric care for SSc patients with abnormalities can reduce pedal complications.

The Demonstration Engineering Data Analysis of Heat Allocation Technique Based on on-Off Time and Area Method in Xingtai

Introduces the construction and operational aspect of 15 plots of existing buildings heat metering demonstration engineering in Xingtai, arranging the average heat consumption of Xingtai city, each plot, each building, every heat user according to the actual operating data. The results of data analysis indicate that the heat allocation technique based on on-off time and area method can characterize the users' demand for the size of the heat correctly, achieve the purpose of a reasonable heat metering. Applying the heat allocation technique based on on-off time and area method in the actual project is feasible, can popularize and apply extensively.

ALL IN ONE TYPE FLUID FLOW SERVO SYSTEM USING SOLENOID VALUE AND ISOTHERMAL PRESSURE VESSEL

Abstract-In general, it tends to become a complex and expensive structure in the controlling of flow rate. In this paper, a simple structure and compact flow rate servo system is shown. It is easy to carry by integrating needed element, that is, the solenoid valve, the isothermal pressure vessel, the pressure sensor and one board controller of on-off method, although, the external compressor is needed. The signal measured with the pressure sensor is sent to the controller, and the proper control signal is feedback to the switching transistor according to on-off timing of the solenoid valve. In this method, the small pressure fluctuation caused by switching action of solenoid valve can not be avoided,�however, this pressure fluctuation enables to examine the actual output flow rate by on-line sampling the pressure and calculation using micro processor on controller. So we execute continuous flow rate control by this compact system alone, and are able to change the output flow rate freely according to manual set up or external control signal. For the evaluation of this system, the blowing up device is adopted to confirm the accuracy of flow rate that is constantly controlled ball height apart from seat.

Simple screening tests for peripheral neuropathy in the diabetes clinic.

The utility of rapid and reliable sensory tests appropriate for the diagnosis of neuropathy in the diabetes clinic, rather than as prognostic tools for the prediction of foot complications, has been unclear because of limitations inherent in previous studies. Although clinical practice guidelines recommend annual screening for neuropathy, they are unable to support specific recommendations for screening maneuvers because of a lack of evidence for the validity of screening tests in the medical literature. The objective of this study was to assess the operating characteristics of four simple sensory screening maneuvers as compared with standardized electrophysiological tests in the diagnosis of distal symmetrical polyneuropathy. We assessed four simple tests (the 10-g Semmes-Weinstein monofilament examination [SWME], superficial pain sensation, vibration testing by the on-off method, and vibration testing by the timed method) in 478 subjects with independent blinded evaluations compared against the criterion standard of nerve conduction studies. We present receiver-operating characteristic (ROC) curves, positive and negative likelihood ratios, and sensitivity and specificity values for each test. The four simple screening maneuvers reveal similar operating characteristics. Cutoff points by ROC curve analyses reveal that a positive or abnormal test is represented by five incorrect responses of eight stimuli applied. A negative or normal test is represented by one or fewer incorrect responses of eight stimuli applied. By these criteria, the point estimates of the positive likelihood ratios for vibration testing by the on-off method, vibration testing by the timed method, the SWME, and superficial pain sensation test are 26.6, 18.5, 10.2, and 9.2, respectively. The point estimates of the negative likelihood ratios are 0.33, 0.51, 0.34, and 0.50, respectively The screening tests showed comparable sensitivity and specificity results. The 10-g SWME, superficial pain test, and vibration testing by the on-off method are rapid, each requiring approximately 60 s to administer. The timed vibration test takes longer, and the interpretation is more complicated. The combination of two simple tests (e.g., the 10-g SWME and vibration testing by the on-off method) does not add value to each individual screening test. Annual screening for diabetic neuropathy should be conducted using superficial pain sensation testing, SWME, or vibration testing by the on-off method. The reported operating characteristics for each sensory modality can be applied to positive findings on the physical examination of individual patients to predict the likelihood of neuropathy.