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排序方式: 共有467条查询结果,搜索用时 15 毫秒
71.
Wireless Personal Communications - Wireless Sensor Networks (WSN) are becoming an imminent result for industrialization, tracking and various other applications. Sensor nodes are deployed in the... 相似文献
72.
Microsystem Technologies - Modular multilevel converter (MMC) is an enhanced multilevel converter topology. It is widely used in research nowadays for its superior performance in high-voltage... 相似文献
73.
Malcolm Townsend Thanh Le Quoc Gaurav Kapoor Hao Hu Wei Zhou Selwyn Piramuthu 《Information & Management》2018,55(4):422-429
Effective data acquisition for business process monitoring has become a critical element in today’s business world. While the need for monitoring is generally agreed upon by both re- searchers and practitioners alike, the means and mechanisms are often vague. This is especially salient with the fast growing availability of various technologies to monitor in real-time through recent advances such as the Internet of Things (IoT) with specific emphasis on Radio-Frequency IDentification (RFID) and associated sensor networks. This study is motivated by the lack of published literature in data acquisition and analytics that specifically addresses sufficient real-time data acquisition for effective managerial monitoring. As a step in addressing this void, we review and extend existing literature in this general area by studying various requirements and information sources that relate to effective management monitoring. We then design an exploratory study to evaluate current managerial monitoring needs and the importance of automated data collection technologies. Results from this study show that the most important latent factor that influences an organization’s information need is its dynamic competitiveness, and consequently, companies with a dynamic supply chain would need a faster transaction and operations data system. The second important latent factor is the behavioral performance, which renders it essential to have a human-centric data system. This study provides evidence for the significance in adopting technologies such as RFID and other IoT systems for real-time monitoring in highly dynamic organizations and offers guidelines for analytical technology adoption for various industries. 相似文献
74.
S. R. Menon S. G. Kapoor R. B. Blackmon 《The International Journal of Advanced Manufacturing Technology》1988,3(4):47-62
This paper deals with the problem of navigation and planning of an automated warehouse equipped with mobile robotic devices.
A generalised layout of the warehouse is considered here, which is a modular construction type. The path planning algorithm
(optimises the path for the shortest distance to the goal) and the collision avoidance strategy for a multiple robot environment
are developed based on velocity and distance bounds. The landmarks are assumed to supply all pertiment information regarding
the module identification and the movement directions, while the sensors are assumed to be capable of maintaining the robot
in its correct track and understand the knowledge contained in the landmarks. The path planning and collision avoidance algorithms
are programmed and simulated for a multiple robot environment in a construction site warehouse. 相似文献
75.
Experimental testing was completed to study the load/displacement and energy-absorption characteristics of AA6061-T6 round extrusions under a cutting deformation mode. A heat-treated 4140 steel alloy cutter was designed and manufactured with four cutting blades of approximate average thickness of 1.18 mm to penetrate through the round AA6061-T6 extrusions. The specimens utilized in this experimental investigation were tubes of lengths 200 and 300 mm with a nominal wall thickness of 3.175 and an external diameter of 50.8 mm. Results from the experimental tests showed that the cutting deformation mode exhibited a high average crush force efficiency of 0.95 compared to average values of 0.66 and 0.20 for progressive folding and global bending deformation modes, respectively. An almost constant cutting force was observed during the cutting deformation process. For both the 200 and 300 mm length tubes, the average total energy absorption was observed to be 6.11 kJ, which was independent of tube length. The mean steady-state cutting force observed was 45.58 kN and a fair correspondence was found between the theoretical predictions and the experimental results. 相似文献
76.
Studies on energetic compounds. Part XI: preparation and thermolysis of polynitro organic compounds.
The thermolysis of high energetic polynitro organic compounds has been reviewed in the present communication. 相似文献
77.
The major purpose of this paper is to find an alternative configuration that not only minimizes the limitations of single-gate (SG) MOSFETs but also provides the better replacement for future technology. In this paper, the electrical characteristics of SiGe double-gate N-MOSFET are demonstrated and compared with electrical characteristics of Si double-gate N-MOSFET. Furthermore, in this paper the electrical characteristics of Si double-gate N-MOSFET are demonstrated and compared with electrical characteristics of Si single-gate N-MOSFET. The simulations are carried out for the device at different operational voltages using Cogenda Visual TCAD tool. Moreover, we have designed its structure and studied both Id-Vg characteristics for different voltages namely 0.05, 0.1, 0.5, 0.8, 1 and 1.5 V and Id-Vd characteristics for different voltages namely 0.1, 0.5, 1 and 1.5 V at work functions 4.5, 4.6 and 4.8 eV for this structure. The performance parameters investigated in this paper are threshold voltage, DIBL, subthreshold slope, GIDL, volume inversion and MMCR. 相似文献
78.
Amit Kumar Kohli Divneet Singh Kapoor 《Circuits, Systems, and Signal Processing》2016,35(10):3595-3618
This paper presents adaptive channel prediction techniques for wireless orthogonal frequency division multiplexing (OFDM) systems using cyclic prefix (CP). The CP not only combats intersymbol interference, but also precludes requirement of additional training symbols. The proposed adaptive algorithms exploit the channel state information contained in CP of received OFDM symbol, under the time-invariant and time-variant wireless multipath Rayleigh fading channels. For channel prediction, the convergence and tracking characteristics of conventional recursive least squares (RLS) algorithm, numeric variable forgetting factor RLS (NVFF-RLS) algorithm, Kalman filtering (KF) algorithm and reduced Kalman least mean squares (RK-LMS) algorithm are compared. The simulation results are presented to demonstrate that KF algorithm is the best available technique as compared to RK-LMS, RLS and NVFF-RLS algorithms by providing low mean square channel prediction error. But RK-LMS and NVFF-RLS algorithms exhibit lower computational complexity than KF algorithm. Under typical conditions, the tracking performance of RK-LMS is comparable to RLS algorithm. However, RK-LMS algorithm fails to perform well in convergence mode. For time-variant multipath fading channel prediction, the presented NVFF-RLS algorithm supersedes RLS algorithm in the channel tracking mode under moderately high fade rate conditions. However, under appropriate parameter setting in \(2\times 1\) space–time block-coded OFDM system, NVFF-RLS algorithm bestows enhanced channel tracking performance than RLS algorithm under static as well as dynamic environment, which leads to significant reduction in symbol error rate. 相似文献
79.
Erörterungen zur homogenen Keimbildung und zur Berechnung der kritischen Übersättigung bei der Desoxidation von Eisenschmelzen mit Mangan. Behandlung des Wachstums der Desoxidationsprodukte durch Diffusion und Kollision. Aussagen über die zeitliche Verteilung der Desoxidationsprodukte unter Berücksichtigung von Stokes- und Gradient-Kollision. Angaben über die Bedeutung der Grenzflächenspannung zwischen Schmelze und Einschluß für die Abscheidung der Desoxidationsprodukte. 相似文献
80.