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141.
Flexible sensing technologies that play a pivotal role in endowing robots with detection capabilities and monitoring their motions are impulsively desired for intelligent robotics systems. However, integrating and constructing reliable and sustainable flexible sensors with multifunctionality for robots remains an everlasting challenge. Herein, an entirely intrinsic self-healing, stretchable, and attachable multimodal sensor is developed that can be conformally integrated with soft robots to identify diverse signals. The dynamic bonds cross-linked networks including the insulating polymer and conductive hydrogel with good comprehensive performances are designed to fabricate the sensor with prolonged lifespan and improved reliability. Benefiting from the self-adhesiveness of the hydrogel, strong interfacial bonding can be formed on various surfaces, which promotes the conformable integration of the sensor with robots. Due to the ionic transportation mechanism, the sensor can detect strain and temperature based on piezoresistive and thermoresistive effect, respectively. Moreover, the sensor can work in triboelectric mode to achieve self-powered sensing. Various information can be identified from the electrical signals generated by the sensor, including hand gestures, soft robot crawling motions, a message of code, the temperature of objects, and the type of materials, holding great promise in the fields of environmental detection, wearable devices, human-machine interfacing, and robotics.  相似文献   
142.
Sophisticated sensing and actuation capabilities of many living organisms in nature have inspired scientists to develop biomimetic somatosensory soft robots. Herein, the design and fabrication of homogeneous and highly conductive hydrogels for bioinspired somatosensory soft actuators are reported. The conductive hydrogels are synthesized by in situ copolymerization of conductive surface-functionalized MXene/Poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) ink with thermoresponsive poly(N-isopropylacrylamide) hydrogels. The resulting hydrogels are found to exhibit high conductivity (11.76 S m−1), strain sensitivity (GF of 9.93), broad working strain range (≈560% strain), and high stability after over 300 loading–unloading cycles at 100% strain. Importantly, shape-programmable somatosensory hydrogel actuators with rapid response, light-driven remote control, and self-sensing capability are developed by chemically integrating the conductive hydrogels with a structurally colored polymer. As the proof-of-concept illustration, structurally colored hydrogel actuators are applied for devising light-driven programmable shape-morphing of an artificial octopus, an artificial fish, and a soft gripper that can simultaneously monitor their own motions via real-time resistance variation. This work is expected to offer new insights into the design of advanced somatosensory materials with self-sensing and actuation capabilities, and pave an avenue for the development of soft-matter-based self-regulatory intelligence via built-in feedback control that is of paramount significance for intelligent soft robotics and automated machines.  相似文献   
143.
论文通过对病毒及反病毒技术的发展分析,总结了现有一些较优秀的杀毒软件的优缺点,提出了基于新理念的攻防查杀型杀毒软件的实现模型。  相似文献   
144.
Large inrush currents can be harmful to equipment subjected to it and can also disturb other devices through voltage dips. Traditional ways of dealing with large inrush currents include the usage of parasitic elements in the supply, negative temperature coefficient (NTC) resistances and start-up relays. These solutions have several disadvantages among which are a non-negligible standby consumption, using a relay or a compromise between inrush current and load losses using an NTC. This paper proposes a solution which solves these disadvantages. The proposed circuit uses a semi-controlled bridge rectifier requiring a very low standby power consumption and is capable of withstanding grid interruptions. Moreover, it is designed to power on only when the load is not too heavy. This is accomplished by the use of positive temperature coefficient thermistors. The presented solution can be used for DC-link start-up circuits in applications with a power range from several watts up to a few kilowatts and it is particularly suitable for on-board battery chargers designed for electrical vehicles.  相似文献   
145.
Ionic soft actuators, which exhibit large mechanical deformations under low electrical stimuli, are attracting attention in recent years with the advent of soft and wearable electronics. However, a key challenge for making high‐performance ionic soft actuators with large bending deformation and fast actuation speed is to develop a stretchable and flexible electrode having high electrical conductivity and electrochemical capacitance. Here, a functionally antagonistic hybrid electrode with hollow tubular graphene meshes and nitrogen‐doped crumpled graphene is newly reported for superior ionic soft actuators. Three‐dimensional network of hollow tubular graphene mesh provides high electrical conductivity and mechanically resilient functionality on whole electrode domain. On the contrary, nitrogen‐doped wrinkled graphene supplies ultrahigh capacitance and stretchability, which are indispensably required for improving electrochemical activity in ionic soft actuators. Present results show that the functionally antagonistic hybrid electrode greatly enhances the actuation performances of ionic soft actuators, resulting in much larger bending deformation up to 620%, ten times faster rise time and much lower phase delay in a broad range of input frequencies. This outstanding enhancement mostly attributes to exceptional properties and synergistic effects between hollow tubular graphene mesh and nitrogen‐doped crumpled graphene, which have functionally antagonistic roles in charge transfer and charge injection, respectively.  相似文献   
146.
This paper proposes a new procedure to adjust soft handoff thresholds dynamically by using fuzzy inference system. This algorithm is compared with IS-95A and IS-95B/cdma2000 soft handoffs. The aims are to increase the thresholds at high traffic loads in order to release the traffic channel for supporting more carried traffic, and to decrease the thresholds at low traffic loads in order to give high quality of traffic channel. The inputs of the proposed algorithm are the number of remaining channels of each base station and the number of active pilots in active set of each mobile station. The output is the new soft handoff thresholds. In the fuzzy inference module, the triangular membership function, the max-min composition, and the weighted average formula defuzzification are selected. By comparison of all performance indicators among three algorithms, soft handoff using fuzzy inference tends to give higher performance than those of IS-95A and IS-95B/cdma2000 soft handoffs at high traffic loads and at lower soft handoff thresholds while the quality of traffic channel is still acceptable. Moreover, the wider soft handoff window size of the proposed algorithm gives high carried traffic and low blocking probability but lower quality of traffic channels. In addition, the adaptive soft handoff window size can give lower blocking probability while still keep acceptable quality of traffic channels.  相似文献   
147.
朱军 《通信技术》2002,(6):38-39
针对衰减信道卷积码的译码,给出了当信道附加噪声非固定时,计算最优软判决度量的表达式。仿真结果表明,在适当的信噪比条件下,采用该方法比硬判决的信噪比提高2dB。  相似文献   
148.
以美军CBU-94型断电弹药的战术应用为背景,探讨了其战术使用过程和作用原理.将导电纤维的落点分三个阶段进行计算,论述了子弹抛物线运动、纤维卷抛物线运动和导电纤维随风运动的计算方程,给出了以导电纤维落点为坐标原点,断电弹药投放时的坐标参数的计算方法,在已知目标点的GPS坐标的前提下,可以通过专门的三维坐标计算软件,计算出断电弹药投放时的GPS坐标.  相似文献   
149.
Three‐dimensional structures that undergo reversible shape changes in response to mild stimuli enable a wide range of smart devices, such as soft robots or implantable medical devices. Herein, a dual thiol‐ene reaction scheme is used to synthesize a class of liquid crystal (LC) elastomers that can be 3D printed into complex shapes and subsequently undergo controlled shape change. Through controlling the phase transition temperature of polymerizable LC inks, morphing 3D structures with tunable actuation temperature (28 ± 2 to 105 ± 1 °C) are fabricated. Finally, multiple LC inks are 3D printed into single structures to allow for the production of untethered, thermo‐responsive structures that sequentially and reversibly undergo multiple shape changes.  相似文献   
150.
While microparticle (MP) assemblies have long attracted academic interest, few practical applications of assembled MPs have been achieved because of technological difficulties related to MP synthesis, MP position registration, and the absence of device concepts. The precise positioning of functional MPs in a proper stencil can produce flexible/stretchable electronic devices, even when the MPs themselves are rigid. In recent years, remarkable progress has been made in the programmable position registration of MPs, production of functional MPs, and concepts for MP‐based, pixel‐type electronic devices. This progress report reviews the recent technological advances in MP assembly and discusses the technological challenges preventing the realization of the one‐particle/one‐pixel concept.  相似文献   
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