Impedance Spectroscopy applied to the study of high dilutions of Lycopodium clavatum

Introduction: The Impedance spectroscopy [1] is a technique mainly used to characterize the electrical behavior of solids or liquids samples. This particular technique involves placing the sample of material under investigation between two electrodes (capacitor plates), applying an AC voltage and observing the resulting response across the spectrum of impedance by plotting the real part (Z’) as a function of the imaginary part (Z”) of the impedance. Alternatively, graphs of either the real or the imaginary parts of the impedance can be constructed as a function of the applied voltage frequency. Comparative measurements previously carried out by Miranda et al [2]. have demonstrated clear differences between the impedance values of high dilutions of lithium chloride (LiCl) and the corresponding reference water samples (water which has undergone the same dinamization procedures but without the salt). In this paper the results obtained by applying the spectroscopy of impedance technique in high dilutions of Lycopodium clavatum - Lyc (from 15cH to 30 cH), in comparison to the reference waters, will be presented and discussed. Aims: The objective of this work is to measure the impedance components of both high dilutions of Lycopodium clavatum and reference water samples in the frequency range of 100Hz to 13Mhz, using a successful protocol of sample preparation which has already been used before2. Details of the experimental set-up can be found elsewhere[3]. Methodology: Thirty samples of Lyc solutions and thirty reference water samples were produced using the same preparation and measuring protocol. Both groups of liquid samples were measured for dynamizations ranging from 1cH to 30cH, in accordance to the Hahnemanian dynamization method and following the practice suggested by the Brazilian Homeopathic Pharmacopeia. The Lyc solutions were specifically compared to the reference water samples in the potencies of 15cH, 18cH, 23cH and 30cH. It is important to highlight here that all the Lyc solutions and the corresponding reference water samples measured were prepared from the same lot of initial distilled water and submitted to the same steps of dilution and succussion protocol3. Typically three impedance measurements were carried out for each investigated solution, starting with the highest potency. The sample holder (capacitor cell) used during the experiment was careful and systematically cleaned after each measurement. Results: The results obtained show that by choosing either the real part (Z’) or the imaginary component (Z”) of the impedance, it is possible to clearly differentiate the Lyc solutions from the corresponding reference water samples, for the potencies 15cH, 18cH and 30cH. For the potency 23cH, however, this difference is not very significant, as it can be observed in Figure 1. Conclusion: Impedance spectroscopy has demonstrated itself to be a powerful and sensitive technique for the physical characterization of Lycopodium clavatum in high dilutions. The differences obtained for the LiCl dynamizations and the corresponding pure water samples are noteworthy. Also, the results exhibit a non-monotonic behavior over the process of dynamization, indicating that the possibility of contamination during the samples manipulation can be ruled out.

Energy-Efficient Hybrid Unicore Architecture In Future Embedded Chip-Multiprocessor

Recently, technology scaling has enabled the placement of an increasing number of cores, in the form of chip-multiprocessors (CMPs) on a chip and continually shrinking transistor sizes to improve performance. In this context, power consumption has become the main constraint in designing CMPs. As a result, uncore components power consumption taking increasing portion from the on-chip power budget; therefore, designing power management techniques, particularly memory and network-on-chip (NoC) systems, has become an important issue to solve. Consequently, a considerable attention has been directed toward power management based on CMPs components, particularly shared caches and uncore interconnected structures, to overcome the challenges of limited chip power budget.<div>This work targets to design an energy-efficient uncore architecture by using heterogeneity in components (cache cells) and operational parameters (Voltage/Frequency). In order to ensure the minimum impact on the system performance, a run-time approach is investigated to assess the proposed method. An architecture is proposed where the cache layer contains the heterogenous cache banks in all placed in one frequency voltage domain. Average memory access time (AMAT) was selected as a network monitor to monitor the performance on the run-time. The appropriate size and type of the last level cache (LLC) and Voltage/Frequency for the uncore domain is adjusted according to the calculated AMAT which indicates the system demand from the uncore.<br></div><div>The proposed hybrid architecture was implemented, investigated and compared with the a baseline model where only SRAM banks were used in the last level cache. Experimental results on the Princeton Application Repository for Shared-Memory Computers (PARSEC) benchmark suit,show that the proposed architecture yields up to a 40% reduction in overall chip energy-delay product with a marginal performance degradation in average of -1.2% below the baseline one. The best energy saving was 55% and the worse degradation was only 15%.<br></div>

Energy-Efficient Hybrid Unicore Architecture In Future Embedded Chip-Multiprocessor

Recently, technology scaling has enabled the placement of an increasing number of cores, in the form of chip-multiprocessors (CMPs) on a chip and continually shrinking transistor sizes to improve performance. In this context, power consumption has become the main constraint in designing CMPs. As a result, uncore components power consumption taking increasing portion from the on-chip power budget; therefore, designing power management techniques, particularly memory and network-on-chip (NoC) systems, has become an important issue to solve. Consequently, a considerable attention has been directed toward power management based on CMPs components, particularly shared caches and uncore interconnected structures, to overcome the challenges of limited chip power budget.<div>This work targets to design an energy-efficient uncore architecture by using heterogeneity in components (cache cells) and operational parameters (Voltage/Frequency). In order to ensure the minimum impact on the system performance, a run-time approach is investigated to assess the proposed method. An architecture is proposed where the cache layer contains the heterogenous cache banks in all placed in one frequency voltage domain. Average memory access time (AMAT) was selected as a network monitor to monitor the performance on the run-time. The appropriate size and type of the last level cache (LLC) and Voltage/Frequency for the uncore domain is adjusted according to the calculated AMAT which indicates the system demand from the uncore.<br></div><div>The proposed hybrid architecture was implemented, investigated and compared with the a baseline model where only SRAM banks were used in the last level cache. Experimental results on the Princeton Application Repository for Shared-Memory Computers (PARSEC) benchmark suit,show that the proposed architecture yields up to a 40% reduction in overall chip energy-delay product with a marginal performance degradation in average of -1.2% below the baseline one. The best energy saving was 55% and the worse degradation was only 15%.<br></div>

THE IDENTIFICATION OF INDUCTION MOTOR INTERNAL QUANTITIES

In the presented work a new identification method of difficult measured internal quantities of IM, such as components of magnetic flux vector and electromagnetic torque, is proposed. Commonly measurable quantities of IM like stator currents, stator voltage frequency and mechanical angular speed are used for identification to determine a feedback effect of the rotor flux vector on vector of stator currents of IM. Based on this feedback it is also possible to identify actual value of the rotor resistance, which can alter during IM operation. This has a significant impact on precision of identified quantities as well as on master control of IM. Stability of the identification structure is guaranteed by position of roots of characteristic equation of its linear transfer function. Results obtained from simulation measurements confirm quality, effectivity, feasibility, and robustness of the proposed identification method.

Optimal Sizing and Assessment of a Renewable Rich Standalone Hybrid Microgrid Considering Conventional Dispatch Methodologies

This paper presents an evaluation of the optimized design of an off-grid hybrid microgrid for alternative load dispatch algorithms with the determination of the most optimal sizing of each equipment, analyzing the voltage and frequency outputs and various costs of the proposed microgrids. Kushighat and Rajendro Bazar, two geographical locations in Bangladesh have been taken as test sites. The proposed microgrids incorporating diesel generator, renewable resources, storage device, and 23.31 kW of demand have been optimized for five conventional load dispatch methodologies: HOMER predictive dispatch, Load Following, Generator Order, Cycle Charging, and Combined Dispatch to reduce the system’s net present cost, gas discharge and cost of energy. HOMER (Hybrid Optimization of Multiple Electric Renewables) software has been used for the analysis to determine the optimal sizes and costing and the voltage-frequency performances of the microgrids are analyzed using MATLAB/Simulink. From our analysis, load following is determined as the superior approach with a minimum operating cost of 3738 USD, net present cost of 152,023 USD, CO2 discharge of 3375 kg/year and cost of energy of 0.208 USD /kWh along with a steady voltage-frequency output. Combined dispatch is determined as the worst strategy for the proposed microgrids with the highest energy cost of 0.532 USD /kWh, the operational cost of 15,394 USD, net present cost of 415,030 USD, and high CO2 discharge. At the end of this work, a comparative analysis between the proposed design, another hybrid, and traditional generation plant is also presented. The findings of this work will be appropriate for any location with an identical demand profile and meteorological estate.

Mismatch of frequencies of ac voltage and streamers propagation in cold atmospheric plasma jet for typical regimes of cancer cell treatment

Cold atmospheric plasma (CAP) jet generated by the plasma source at 2-6 kV ac voltages with frequencies of 10-50 kHz demonstrate the different modes of operation. Depending on the voltage frequency and amplitude, some streamers in the plasma jet are short and decay before they approach the treated surface. In this case, the effect on the viability of cancer cells when exposed to CAP jet strongly depends on the mode of operation of the discharge or, in other words, on how many times the streamers hit the bio-target during the treatment. The effect on different modes on cancer cells A549 viability is reported.

Analisis pengaruh penambahan gardu induk Guluk-Guluk terhadap aliran daya dan profil tegangan pada sub sistem Krian Gresik

Kestabilan suatu sistem tenaga listrik sendiri merupakan kemampuan sebuah sistem tenaga listrik dalam mempertahankan tegangan, frekuensi, dan daya di setiap bus sistem interkoneksi pada kondisi normal baik sebelum dan sesudah terjadinya gangguan. Sistem akan memasuki keadaan ketidakstabilan ketika terjadi gangguan, peningkatan permintaan beban dan adanya perubahan kondisi sistem, keadaan tersebut akan menyebabkan penurunan performa sistem tenaga listrik. Pada tahun 2015-2019 pulau madura hanya terdapat lima gardu induk, seiring dengan pertambahan kebutuhan tenaga listrik di beberapa wilayah pulau madura, untuk memperbaiki mutu dan keandalan penyaluran tenaga listrik ke konsumen, hal inilah yang mendukung proyek penambahan Gardu Induk Guluk Guluk. Gardu Induk Guluk-Guluk merupakan salah satu bagian dari sub sistem Krian Gresik. Dengan adanya penambahan Gardu Induk Guluk-Guluk tersebut akan berpengaruh terhadap aliran daya dan tegangan pada sistem tenaga listrik. Analisis dilakukan pada kondisi normal sebelum dan setelah adanya Gardu Induk Guluk-Guluk. Kondisi tegangan pada sub sistem Krian Gresik saat sebelum dan sesudah pembangunan Gardu Induk Guluk-Guluk masih memenuhi standart, namun ada beberapa bus yang mengalami penurunan tegangan dibawah 95%. Gardu Induk yang mengalami penurunan tegangan dibawah 95% sebelum pembangunan Gardu Induk Guluk-Guluk, yaitu pada Gardu Induk Bunduran, Gardu Induk Porong, dan Gardu Induk Maspion. Saat setelah pembangunan Gardu Induk Guluk-Guluk, terdapat penambahan Gardu induk yang mengalami penurunan nilai tegangan, yaitu Gardu Induk Sampang, Gardu Induk Pamekasan, Gardu Induk Guluk-Guluk, dan Gardu Induk Sumenep. Aliran daya terbesar saat terjadi penurunan tegangan adalah pada bus Bus 1 Bunduran. The stability of an electric power system itself is the ability of an electric power system to maintain the voltage, frequency, and power in each interconnecting bus system in normal conditions both before and before the disturbance. The system will enter a state of instability when there is a disturbance, an increase in load demand and a change in system conditions, this situation will cause a decrease in the performance of the electric power system. In 2015-2019 Madura Island there are five substations, along with the increasing need for energy in the Madura Island area, to improve some and control electric power, this is what supports the addition of Guluk-Guluk Substations. Guluk-Guluk Substation is one part of the Krian Gresik sub-system. With the addition of the Guluk-Guluk Substation, it will affect the flow of power and voltage in the electric power system. The analysis was carried out under normal conditions before and after the Guluk-Guluk Substation. The voltage conditions in the Krian Gresik sub-system before and before the construction of the Guluk-Guluk Substation still met the standard, but there were several buses that experienced a voltage drop below 95%. Substations that experienced a voltage drop below 95% before the construction of the Guluk-Guluk Substations, namely the Bunduran Substation, Porong Substation, and Maspion Substation. After the construction of the Guluk-Guluk Substation, there were additional substations that experienced a decrease in voltage values, namely the Sampang Substation, Pamekasan Substation, Guluk-Guluk Substation, and Sumenep Substation. The largest power flow when there is a voltage drop is on the Bus 1 Bunduran.

The resistive ground fault of PWM voltage inverter in the EV charging station

During the direct touch of the inverter output voltage or with the ungrounded shield of the cable connecting the inverter to the motor or other type of load, the nonsinusoidal ground currents with a basic harmonic frequency between 1.5 and 16 kHz, flow via a human’s body. Here was proved that Residual Current Device (RCD) ($$I_{\triangle n}$$ I ▵ n = 30 mA) does not switch off the power supply when a ground current with a value of about some hundred milliamps occurs. Because RCDs do not disconnect the power supply, the touch on the inverter’s voltage is dangerous to health and life. For the authors, the RCD usage in the Voltage Frequency Converters (VFCs) is not a good engineer practice when high-frequency common-mode distortion currents flow through it. The paper presents tests of RCD operation in the event of a resistance ground fault (via human body) during EV battery charging where the PWM voltage inverter is connected to the external rectifier to provide DC charging battery voltage. Finally, the authors propose a method of eliminating common-mode (CM) current from short protection system by using a separate circuit in which the parasitic leakage current omits an RCD.