Single Duty Cycle Research Articles

Role of AGN and star formation feedback in the evolution of galaxy outflows

Abstract We conducted 3D-MHD simulations to investigate the feedback processes in the central 1-kpc scale of galaxies hosting both active star formation (SF) and an AGN wind. Our simulations naturally generated a turbulent and clumpy interstellar medium driven by SF evolution. We found that the AGN wind duty cycle plays a crucial role in shaping the evolution of the outflows. A single duty cycle (which can repeat several times over the galaxy lifetime) consists of an active, a remnant and an inactive phase, lasting up to 1.5 Myr in our simulations. The duration of the cycle increases with larger star formation rate (SFR) and smaller AGN wind power (tested for luminosities 1042 − 1044 erg s−1 and SFR=1 – 1000 M⊙ yr−1). The feedback on SF, whether positive or negative, depends on various factors, including the AGN outflow opening angle, power, and phase of activity, as well as the initial SFR. The passage of the AGN wind enhances SF in a ring around it, resembling the structures observed in ULIRGs and LINERS, and is stronger for larger AGN power or SFR. Also, a higher SFR enhances the mixing of interstellar matter with the AGN wind, resulting in a greater number of colder, denser structures with volume filling factors ∼ 0.02 to 0.12 and velocities comparable to those observed in Seyferts and LINERs, but smaller than those observed in ULIRGs. The efficiency of the AGN wind in transporting mass to kiloparsec distances diminishes with increasing SFR. The mass loss rates range from 50 to 250 M⊙ yr−1 within the initial 2 Myr of evolution, which aligns with observed rates in nearby Seyferts and ULIRGs.

Design of smart light source based on bi-color LED with single duty cycle for correlated color temperature adjustment

Color-adjustable light sources facilitate both mood lighting and daylight harvesting. A single duty cycle can be used by a bi-color LED to adjust the correlated color temperature (CCT) by associating it with the duty cycle of the pulse width modulation dimming signal of the cool and warm white LEDs. The one-to-one mapping relationship between the single duty cycle and the CCT is based on the color mixing theory of bi-color LEDs. A method to correlate the dimming signals for bi-color LEDs is presented. The influence of the time characteristics of the two basic signals on dimming and CCT adjustment is analyzed. The dimming system of bi-color LEDs is designed, and the method used to adjust the CCT with a single duty cycle is verified. The experiment showed that the CCT can be accurately adjusted by the proposed method.

Multi Duty Cycle Scheduled Routing in Wireless Sensor Network-lifetime Maximization

Cluster-based protocols are best for applications that require reliability and a continuous functioning environment with a sustainable lifetime of WSN. The dynamic nature of the sensor node makes energy conservation a challenging issue. Sensor node scheduled based on sensing error for energy conservation compromise the accuracy of prediction. The high data accuracy achieved using a single duty cycle controller at each node with compromised throughput and increased routing overhead. Duty Cycle Controller managing a more number of control messages at the network level leads to control packet interference with data packet transmission, increasing packet drop and minimizing throughput. Also, the single-duty cycle controller at the network level leads to increased control overhead. The proposed multilevel cluster-based approach focuses on the appropriate cluster design, selection of cluster head, and sensor nodes scheduling based on sensing error. The proposed method applies a multi-duty cycle controller at each cluster level, and control messages handled are related to nodes in a cluster. Thus has less interference and packet drop leading to maximum throughput than existing methods. The simulation results demonstrated that the proposed method with sensor nodes scheduled at individual cluster levels using a multi-duty cycle controller exhibited improved network lifetime, throughput, and reduced energy consumption compared with the state-of-the-art techniques.

Анализ особых положений плоского многозвенного рычажного механизма четвертого класса

The planar multi-linkage mechanism of the fourth order, the output rocker of which implements an approximate stopping in one critical position is described in the article. The mechanism consists of three dyads passing through their limit positions in a single duty cycle. That is why the singularity problem is relevant for such mechanisms and should be studied to avoid jamming of links or the appearance of uncontrolled movements. The mathematical model is based on the theory of screws and contains the closed-loop equilibrium equations obtained for the investigated mechanism. Based on the obtained results of the geometry and singularity analyses, it is shown that there are eight different positions in which some joints stop momentarily and then their angular velocity direction changes

Optimal Hop Extended MAC protocol for wireless sensor networks

In wireless sensor MAC protocols, duty cycling has been exploited to put sensor nodes into sleeping state most of the time, thereby saving the limited battery efficiently. In this paper, we present a MAC protocol called Hop Extended MAC (HE-MAC) that enables a source node to transmit a data packet for multiple hops in a single duty cycle. It employs an EXP (Explorer) frame to set up the path for multiple hop transmission, which contains the information about the maximum number of hops that a packet can travel through in a single duty cycle. Using this information and an internal state of Ready-to-Receive (RTR), HE-MAC relays the packet beyond the termination of the data period. Along with our adaptive sleeping method, it additionally reduces power consumption. Then, we analytically obtain the packet latency of HE-MAC and find its optimal wakeup duration with respect to packet latency. Through ns-2 simulations, we observe that HE-MAC achieves 42.2% less power consumption and 23.6% less packet delay on average compared to RMAC [9] for a random topology of 300 nodes. With the allocated optimal wakeup duration, the latency of HE-MAC is reduced by 54.3% at maximum and 41.1% on average, compared to the case of default setting.

Duty cycle optimization for a multi hop transmission method in wireless sensor networks

Several synchronous and asynchronous MAC protocols have been proposed for wireless sensor networks (WSNs). Among these, RMAC exploits a control frame named Pioneer (PION) to set up the path and transmit a data packet through multiple hops in a single duty cycle. In this letter, we numerically analyze the average packet latency of RMAC in a probabilistic manner, which can be easily applied for any multi hop transmission methods. To evaluate the accuracy of the numerical analysis, we compare the analysis results with the ns-2 simulation results. Then we mathematically obtain an optimal duty cycle value that minimizes the average power consumption while satisfying a given delay bound.

Frequency response in pulsed DC reactive sputtering processes

By simple arguments as well as results from a recently developed computer simulation model we have found out that for high frequency pulsed DC reactive sputtering the target poisoning does not reflect the periodicity of the pulsed DC power supply. The degree of target poisoning does not change markedly during a single duty cycle. The degree of poisoning essentially exhibits the same continuous time independent behavior as observed for the conventional continuous reactive sputtering process. Furthermore, it is shown that the distribution width of the transit times for sputtered atoms by far exceeds the period time for pulsed DC frequencies higher than 5–10 kHz. This causes a large overlap between sputter eroded material between consecutive pulses during processing resulting in an essentially continuous arrival rate of sputtered atoms to the substrate surface. This implies also that the deposition rate will be constant and will not follow the pulsed sputter erosion variation from the target. These findings show that, with respect to film stoichiometry and homogeneity, the high frequency pulsed DC reactive sputtering process behaves identically as the continuous reactive sputtering process. No chemical reaction effects or gas gettering variations will follow the periodicity of the pulsed DC power supply at high frequencies.

Aspects of nickel-cadmium cells in single cycle applications. III. Effects of electrolyte additives on cadmium hydroxide crystal growth in sintered nickel negative electrodes during discharged storage

The single duty cycle application requires nickel-cadmium cells to be stored for long periods in a discharged, short-circuited state. Under these conditions Cd(OH)2 active material in the negative electrode is subject to crystal growth processes which result in reduced charge efficiency when cycled after storage. Of equal importance, however, is the observed gross redistribution of Cd(OH)2 active material, whereby crystals penetrate into the separator, sometimes as far as the positive electrode. This must be considered undesirable and could lead to internal short-circuiting of the cell. This paper examines the effects of various surfactant electrolyte additives on Cd(OH)2 crystal growth and capacity of sintered, negative electrode material, stored in excess 6 M KOH, at various temperatures between +30 and +60°C. Results show that, under the test conditions, low concentrations (⩽0.1%) of the anionic surfactants sodium lauryl sulphate and turkey red oil strongly suppress Cd(OH)2 growth and result in markedly higher aged electrode capacities compared to control electrodes stored in the absence of these additives.

Aspects of nickel-cadmium cells in single cycle applications. II. Operational temperature effects

The volumetric energy density picture is explored for nickel-cadmium cells in a single duty cycle application, over the operational temperature range −30 to +55° C. Results are presented showing that fresh, precycled cells easily attain the target specification (40–50 W h dm−3) at temperatures at and above room temperature. Charge acceptance falls sharply at sub-zero temperatures however, and energy density reduces to critical levels below −20° C. The charging characteristics and ability to achieve target performance at −30° C depends markedly on cell origin and the permissibility of allowing some cell venting during the charge. The low temperature limitations can be overcome by means of low wattage heating coils on the cells. Internal temperatures of C and D/2 cells can be raised to 20° C within a few minutes by employing very modest temperature gradients and with heater volumes no greater than the manufacturers label and sleeve. Although the picture is optimistic for fresh precycled cells, major problems are anticipated with stored cells, particularly at temperature extremes, unless steps can be taken to prevent or erase storage effects.

Aspects of nickel-cadmium cells in single cycle applications. I. The effects of long term storage

The use of sealed nickel-cadmium cells for single duty cycle applications involves certain novel features for which little or no quantitative knowledge exists. The investigations presented in this series of papers have sought answers to the questions raised in broad terms. This first paper considers the effects of long term storage (up to 10 years), in the short-circuited condition, at temperatures ranging between −40–+70° C. An accelerated test procedure was formulated to determine charge acceptance degradation of cells after storage for any given period and temperature. The results indicate that storage effects will constitute a major problem area for nickel-cadmium cells in these applications.

Electric current from the direct conversion of low molecular weight C,H,O-compounds

This paper gives a report on the results obtained in the development of formate/air fuel cells, and of formate/air, glycol/air and formic acid/air rech A current density of 50 mA cm −2 can be drawn continuously from formate/air fuel cells using alkaline electrolyte. Corresponding formate/air recha By replacement of the formate fuel by ethylene glycol an energy density of 101 Wh kg −1 (single duty cycle) is obtained, and the cost decreases to A considerable number of these elements has already been built and tested; the shift to a small series production appears to be possible immediately. A