Universal Operation Research Articles

Constant DC‐bus critical conduction mode Zeta converter fed primary‐side regulated LLC resonant converter in LED lighting applications

AbstractThis paper deals with a two‐stage high‐power light‐emitting diode (LED) driving solution for an isolated LED load. The first‐stage DC–DC power conversion is using a nonisolated Zeta converter operating in critical conduction mode to reduce component stress and switching power loss. This power stage is accountable for the power factor correction (PFC) under the universal AC voltage operation and developed a constant DC‐bus voltage for the second stage. In the second stage, half‐bridge LLC resonant converter is dedicated to deliver ripple‐free DC voltage to an isolated LED load. A new primary‐side regulation (PSR) technique is implemented in series with the resonant tank to reduce the component counts in the feedback loop. The stability of the DC‐bus voltage is verified by the state‐space analysis for the critical conduction mode (CrCM) Zeta converter. A 150 W load is driven by a prototype with a nearly unity power factor (PF) and low harmonics distortion in the input current.

Multiple-qubit controlled unitary quantum gate for Rydberg atoms using shortcut to adiabaticity and optimized geometric quantum operations

Multiple-qubit quantum logic gates are an important element in the implementation of quantum computers. The direct construction of multiple-qubit quantum logic gates in an efficient way has important values compared to the construction of multiple-qubit gates using a series of two-qubit and single-qubit gates. We propose a scheme to construct a multiple-qubit ${\mathrm{C}}_{k}\mathrm{U}$ gate ($k$ denotes the number of control qubits and U means the arbitrary universal operation performed on the target qubit) in a neutral atom platform through the Rydberg blockade effect by successively exciting them to Rydberg states. This scheme takes advantage of the shortcut to adiabaticity of inverse engineering, geometric quantum operations, as well as optimized control theory. The geometric quantum computation considered in this manuscript guarantees the robustness to operational errors. Meanwhile, inverse engineering-based shortcut to adiabaticity provides a further advantage in terms of the speed of the system evolution compared to adiabatic processes. An additional feature of our multiple-qubit quantum logic gate is that arbitrary operation on the target atom can be realized by adjusting the amplitude and phase of the laser fields. Numerical simulation of the master equation based on the full Hamiltonian demonstrates the high fidelity of the proposed scheme and its robustness to operational errors and spontaneous emission.

Advanced Technologies for Stabilization and High Performance of Seawater RO Membrane Desalination Plants.

Seawater desalination plants that use reverse osmosis (RO) membranes have become a core part of social infrastructure, and should be designed to meet the needs of product water quality and production capacity, while considering various environmental factors such as the seawater quality, temperature and geographical features. Furthermore, stable operation while overcoming various problems should be achieved alongside the increasing demands for energy saving and cost reduction. As no universal plant apparatus and operation technology meets these various requirements, the plants need to be customized for individual solutions. This paper reviews and summarizes the proven technologies, including their advantages/disadvantages, and points to cutting-edge technologies related to the design and operation maintenance of seawater intake, pre-treatment and the RO desalination process.

СТРАТЕГІЯ ПЕРЕАДРЕСАЦІЇ У ХУДОЖНЬОМУ ПЕРЕКЛАДІ

Modern translation studies which are of descriptive nature mainly presuppose the opportunity of altering the function of the source text in translation, reconstruction of sense and structure in correspondence with the aim of translation. The investigation has been carried out in the framework of the communicativefunctional approach to translation which accounts for the entire spectrum of linguistic and extra linguistic factors influencing translation in the broad sense. This fact proves the relevance of the article. The translations of both narrations intended for the children’s audience exclusively conform to the ideology of the children’s fiction aimed at socialization and attraction of young addressees. It results in the loss of the worldview reflection by the originals and focusing on reproducing their fairy–tale plots. The applied readdressing translation strategy has been implemented by the following tactics: the tactic of relevant information rendering, the tactic of pragmatic adaptation of the source text, the tactic of stylistic features rendering, the tactic of the source text formal and structural features rendering. Common operations for the applied tactics have proved to be as following: search for a variant equivalent, omission, restructuring and compensation. The compensation technique has turned out to be the most universal operation within the applied translation tactics. This fact can be explained by the complex nature of transformations the source text is subjected to, the need to omit, rearrange amounts of information and to preserve the chosen genre along with its adaptation for the potential addressee.

Reduplication in Abui: A case of pattern extension

This paper studies the effect of ongoing contact on the Abui reduplication system. Abui, a Papuan indigenous minority language of eastern Indonesia, has been in contact with the regional lingua franca, Alor Malay (Austronesian), for around 50–60 years. Throughout this period, contact with Alor Malay has affected different age groups in different ways across various levels of grammar. Here we compare Abui reduplication across four age groups: (pre)adolescents, young adults, adults, and elders, and show how the function and distribution of reduplication in the Abui spoken by younger speakers is affected by a combination of morphological PAT borrowing and lexical borrowing from Alor Malay. The changing patterns are first applied to the domain in which the two languages overlap: existing Abui verb reduplications become more Alor Malay-like with respect to their function, form, and productivity. The borrowing of an additional function of reduplication is analyzed as a type of complexification in Abui, while at the same time, Abui reduplication itself is demonstrated to also show simplification in terms of form. We argue that this change is induced by decades of stable bilingualism, and is further enhanced by the fact that reduplication is a universal morphological operation and can emerge spontaneously in language contact situations. Thus, the emerging trends reported here are explained by both borrowing from Alor Malay as well as incomplete acquisition of Abui.

Artificial intelligence and philosophical creativity: From analytics to crealectics

Abstract The tendency to idealise artificial intelligence as independent from human manipulators, combined with the growing ontological entanglement of humans and digital machines, has created an “anthrobotic” horizon, in which data analytics, statistics and probabilities throw our agential power into question. How can we avoid the consequences of a reified definition of intelligence as universal operation becoming imposed upon our destinies? It is here argued that the fantasised autonomy of automated intelligence presents a contradistinctive opportunity for philosophical consciousness to understand itself anew as holistic and co-creative, beyond the recent “analytic” moment of the history of philosophy. Here we introduce the concept of “crealectic intelligence”, a meta-analytic and meta-dialectic aspect of consciousness. Intelligent behaviour may consist in distinguishing discrete familiar parts or reproducible functions in the midst of noise via an analytic process of segmentation; intelligence may also manifest itself in the constitution of larger wholes and dynamic unities through a dialectic process of association or assemblage. But, by contrast, crealectic intelligence co-creates realities in the image of an ideal or truth, taking into account the desiring agent imbued with a sense of possibility, in a relationship not only with the Real but also with the creative sublime or “Creal”.

A Novel Hybrid PFM/IAPWM Control Strategy and Optimal Design for Single-Stage Interleaved Boost-LLC AC–DC Converter With Quasi-Constant Bus Voltage

Single-stage boost-LLC ac-dc converters have been a popular soft-switched topology because of the high-efficiency and being cost-effective. However, low power capacity is its main disadvantage. In this article, a novel single-stage interleaved boost-LLC ac-dc converter with higher power capacity is presented while achieving the low input current ripple. However, it still suffers from the wide and high bus voltage for universal operation, as a result of the conventional pulse frequency modulation (PFM) with the duty cycle of 0.5. Furthermore, this wide bus voltage will bring the difficulties in designing the LLC resonant cell. To solve these issues, a dual-loop feedback control strategy based on PFM/interleaved asymmetric pulsewidth modulation hybrid modulation and power balance based optimal design are proposed. With the proposed control strategy and optimal design, the bus voltage of the studied converter is not only significantly reduced, but also zero voltage switching for the primary switches and zero current switching for the secondary diodes are still maintained. Thus, the higher efficiency can be achieved. Operation principles and control scheme for the studied converter are fully addressed. The optimal design based on power balance principle is also discussed in this article. A 300 W prototype is fabricated to validate the theoretical analysis and optimal design. The experimental results demonstrate the prototype can simultaneously obtain the universal operation with high power factor above 0.98 and the quasi-constant bus voltage below 500 V. The measured peak efficiency is 92.7% under 115 Vac input voltage at full load.

A smart DNA tweezer for universal proximity assay and logic building

A smart DNA tweezer was constructed for universal proximity assay and logic building. In this tweezer, the set strand was designed as recognition module, and the ends of two motifs were ingeniously designed as toehold domain (TD) and branch migration domain (BMD). As the recognition of set strand and target, the set strand could be dismantled from the tweezer, resulting in a proximity binding of TD and BMD. Then, the proximal TD and BMD could initiate the dynamic assembly of two complementary hairpins, yeilding a long double-stranded polymer with multiple G-quadruplexes. By inserting fluorescent dye, enhanced fluorescent response could be observed. Universal and sensitive assay of miRNA and thrombin were achieved by altering the sequence of set strand. The corresponding detection limits were 9.4 fM and 0.35 pM. Moreover, quantitative analysis of miRNA in clinical serum sample was also performed, suggesting the feasibility of this proximity assay in clinical application. What’s more, based on the proposed DNA tweezer, a Boolean logic operation platform was fabricated, and systematic logic operations were also achieved. Therefore, this work provided a reliable strategy for universal proximity assay and logic operation, which could be further used in biomedical research and clinical diagnosis.

Modular Hybrid-Full-Bridge DC Transformer With Full-Process Matching Switching Strategy for MVdc Power Distribution Application

This article proposes a modular hybrid-full-bridge dc transformer (MHDCT) with full-process matching switching strategy MHDCT for MVdc power distribution application. The proposed MHDCT merges the advantages of DCTs based on dual-active-bridge and modular multilevel converter, it not only has good reliability, but also has good modularity and flexibility. Especially, full-process matching switching strategy has good voltage regulation ability to ensure the voltage match of high-frequency-link under various states, then circulating current can be decreased and efficiency can be improved. The universal operation and modulation, voltage, current, power, and switching characterizations of MHDCT are analyzed and the control strategy is proposed in this article. Finally, an MHDCT prototype is built and the experimental results verify the correctness and effectively of the proposed solution. The MHDCT will be a practical scheme for MVdc distribution application.

Semi‐Nonlinear Nanophotonic Waveguides for Highly Efficient Second‐Harmonic Generation

AbstractQuadratic optical parametric processes form the foundation for various applications related to classical and quantum frequency conversion, and have attracted significant interest recently in on‐chip implementation. These processes rely on phase matching among the interacting guided modes, and refractive index engineering is a primary approach for this purpose. Unfortunately, modal phase‐matching approaches developed so far only produce parametric generation with fairly low efficiencies, due to the intrinsic modal mismatch of spatial symmetries. Here, a universal design and operation principle is proposed for highly efficient optical parametric generation on integrated photonic platforms. By breaking the spatial symmetry of the optical nonlinearity of the device, nonlinear parametric interactions can be dramatically enhanced. This principle is then employed to design and fabricate a heterogeneous titanium oxide/lithium niobate nanophotonic waveguide that is able to offer second‐harmonic generation with a theoretical normalized conversion efficiency as high as 2900, which enables the measurement of an experimental efficiency of 650, significantly beyond the reach of conventional modal phase‐matching approaches. Unlike nonlinearity domain engineering that is material selective, the proposed operation principle can be flexibly applied to any other on‐chip quadratic nonlinear platform, to support ultra‐highly efficient optical parametric generation.

Scalable analysis for arbitrary photonic integrated waveguide meshes

The advances in fabrication processes in different material platforms employed in integrated optics are opening the path towards the implementation of circuits with increasing degrees of complexity. In addition to the more conventional application specific photonic circuit paradigm, the programmable multifunctional photonics (PMP) approach is a transversal concept inspired by similar approaches, which are already employed in other technology fields. For instance, in electronics, field programmable gate array devices enable a much more flexible universal operation as compared to application specific integrated circuits. In photonics, the PMP concept is enabled by two-dimensional (2D) waveguide meshes for which the number of possible input/outputs ports quickly builds up, and, furthermore, internal signal flow paths make the computation of transfer functions an intractable problem. Here we report a scalable method based on mathematical induction that allows one to obtain the scattering matrix of any 2D integrated photonic waveguide mesh circuit composed of an arbitrary number of cells and that is easily programmable. To our knowledge this is the first report of the kind, and our results open the path to unblocking this important design bottleneck.

Fault Tree Interval Analysis of Complex Systems Based on Universal Grey Operation

The objective of this study is to propose a new operation method based on the universal grey number to overcome the shortcomings of typical interval operation in solving system fault trees. First, the failure probability ranges of the bottom events are described according to the conversion rules between the interval number and universal grey number. A more accurate system reliability calculation is then obtained based on the logical relationship between the AND gates and OR gates of a fault tree and universal grey number arithmetic. Then, considering an aircraft landing gear retraction system as an example, the failure probability range of the top event is obtained through universal grey operation. Next, the reliability of the aircraft landing gear retraction system is evaluated despite insufficient statistical information describing failures. The example demonstrates that the proposed method provides many advantages in resolving the system reliability problem despite poor information, yielding benefits for the function of the interval operation, and overcoming the drawback of solution interval enlargement under different orders of interval operation.

Development Trend and Application Prospect of 3D Printing Technology in the Intelligent Manufacturing

The development of D printing technology is one of the signs known as the third industrial revolution And it is the combination of industrial development and the development of artificial intelligence which greatly promoted the development of modern manufacturing technology and control technology In the future the precision intelligent and convenient universal and stable operation of the D printer will become the future industrialization research focus and development trend

An electrically reconfigurable logic gate intrinsically enabled by spin-orbit materials

The spin degree of freedom in magnetic devices has been discussed widely for computing, since it could significantly reduce energy dissipation, might enable beyond Von Neumann computing, and could have applications in quantum computing. For spin-based computing to become widespread, however, energy efficient logic gates comprising as few devices as possible are required. Considerable recent progress has been reported in this area. However, proposals for spin-based logic either require ancillary charge-based devices and circuits in each individual gate or adopt principals underlying charge-based computing by employing ancillary spin-based devices, which largely negates possible advantages. Here, we show that spin-orbit materials possess an intrinsic basis for the execution of logic operations. We present a spin-orbit logic gate that performs a universal logic operation utilizing the minimum possible number of devices, that is, the essential devices required for representing the logic operands. Also, whereas the previous proposals for spin-based logic require extra devices in each individual gate to provide reconfigurability, the proposed gate is ‘electrically’ reconfigurable at run-time simply by setting the amplitude of the clock pulse applied to the gate. We demonstrate, analytically and numerically with experimentally benchmarked models, that the gate performs logic operations and simultaneously stores the result, realizing the ‘stateful’ spin-based logic scalable to ultralow energy dissipation.

Operational one-to-one mapping between coherence and entanglement measures

We establish a general operational one-to-one mapping between coherence measures and entanglement measures: Any entanglement measure of bipartite pure states is the minimum of a suitable coherence measure over product bases. Any coherence measure of pure states, with extension to mixed states by convex roof, is the maximum entanglement generated by incoherent operations acting on the system and an incoherent ancilla. Remarkably, the generalized CNOT gate is the universal optimal incoherent operation. In this way, all convex-roof coherence measures, including the coherence of formation, are endowed with (additional) operational interpretations. By virtue of this connection, many results on entanglement can be translated to the coherence setting, and vice versa. As applications, we provide tight observable lower bounds for generalized entanglement concurrence and coherence concurrence, which enable experimentalists to quantify entanglement and coherence of the maximal dimension in real experiments.

A Single-Stage PFM-APWM Hybrid Modulated Soft-Switched Converter With Low Bus Voltage for High-Power LED Lighting Applications

In order to design a high-efficiency cost-effective high-power LED driver, a single-stage integrated boost- LLC -type soft-switched ac–dc converter is usually employed. The minimized number of semiconductors and the reduced power loss are its main advantages. However, the high bus voltage is its well-known disadvantage, which is caused by the employment of a conventional pulse frequency modulation (PFM) control strategy with the duty cycle of 0.5. The range of the input ac voltage is severely limited. In order to overcome this problem, a hybrid PFM-asymmetric pulse width modulation strategy is proposed in this paper. The proposed strategy can significantly reduce the bus voltage while maintaining the soft-switching operation for both primary MOSFETs and secondary diodes. Furthermore, the electrolytic capacitors are removed by increasing the bus voltage ripple. Hence, high efficiency, long lifetime, low cost, and universal operation are achieved on the proposed LED driver, which is well matched to the virtues of LED lighting source. The detailed operation principles and design consideration for the proposed modulation approach are analyzed and discussed. The feature of the proposed solution was demonstrated using a universal-input 100-W hardware prototype. The experimental results verified the full-range zero-voltage-switching (ZVS) operation for primary switches and the efficiency achieved 91.6% under the 130-V input voltage.

Improving the Dimming Performance of Low-Power Single-Stage AC–DC HBLED Drivers

The design of efficient single-stage high-brightness light-emitting diodes (HBLEDs) ac–dc drivers with power factor correction (PFC) in low-power applications is addressed in this paper. The PFC is achieved by using a switching converter with both step-up and step-down voltage capability. It is well known that a good tracking of the input reference current close to the zero crossing is challenging, in particular when the LED output current is low, hence jeopardizing the power quality at low power levels. A solution is proposed to improve the power quality in ac–dc LED drivers under inner current loop based on a variable hysteresis modulation scheme. An adaptive hysteresis window modulated by the input voltage and the output LED current reference is used. The double modulation strategy helps to avoid the distortion near the zero crossings of the input current and to improve the dimming performance of the HBLEDs. This results in a low value of total harmonic distortion (THD) under low current/power conditions and therefore in a very good dimming performance in single-stage ac–dc HBLEDs drivers with PFC. The operation principle of the proposed technique is presented and numerical simulations are shown to demonstrate its functionality. A laboratory prototype is designed and tested to verify its feasibility obtaining a significant improvement in terms of power quality. Under universal input voltage operation, good efficiency and low THD can be achieved even for low power levels.

Construction of nanowire CH3NH3PbI3-based solar cells with 17.62% efficiency by solvent etching technique

1D Nanowire CH3NH3PbI3 thin films have been successfully constructed by solvent etching technique. The etching solution was consisted of a small amount of polar solvent in non-polar solvent, and the roughness of the film can be precisely controlled by the adding amount of polar solvent. A best and repeatable PCE of 17.62% was achieved from the CH3NH3PbI3-based solar cells device with nanowire film morphology and p-i-n structure. Solvent etching process was an advanced technique for perovskite nanowire construction because of it's simple, universal and effective operation.

Reactive Power Flow Control for PV Inverters Voltage Support in LV Distribution Networks

This paper proposes a reactive power flow control pursuing the active integration of photovoltaic systems in LV distribution networks. An alternative power flow analysis is performed according to the specific characteristics of LV networks, such as high resistance/reactance ratio and radial topologies. The proposed solution gives high performances, in terms of rms-voltage regulation, by estimating the reactive power reference on each node considering the influence of the rest of the nodes in terms of active and reactive power demanded/generated by them. The local control of each photovoltaic system is based on the power converter control, interfacing these units with the grid and the loads respectively. The local control is designed on the basis of locally measured feedback variables. Photovoltaic units thus guarantee universal operation, being able to change between islanding-mode and grid-connected mode without disrupting critical loads connected to them, and allowing smooth transitions. Exhaustive results are also included and discussed in this paper.

Dual-buck residential photovoltaic inverter with a high-accuracy repetitive current controller

This paper describes a dual-buck inverter (DBI) for residential photovoltaic power conversion systems. The DBI consists of unidirectional and bidirectional switching legs, which are operated at different frequencies to attain high efficiency. The operation modes of the DBI are analyzed and a third- order control model is derived based on the analysis. Since the third-order model cannot be easily handled by the current controller design, a simple first order-model is obtained with proper assumptions and manipulations. After this, a repetitive current controller using the first-order model is designed to improve the accuracy of the current regulation in both continuous and discontinuous conduction modes. Due to the universal operation of the designed repetitive controller, the tracking accuracy for a low power reference is drastically enhanced, and this significantly improves the maximum power point tracking (MPPT) ability of the PV system. In order to verify the performance of the proposed scheme, a 3-kW DBI prototype was built and tested. The experimental results demonstrate that the proposed scheme not only reduces the total harmonic distortion of the output current, but also achieves highly accurate power tracking performance with high efficiency.