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31.
“Manned-Unmanned Teaming” among others refers to the use of an unmanned, flying sensor. One use for this is as an integral part of air units’ flying systems. Secondly, it can be used as an independent, recessed robotic component during missions, even from far away and ahead of time. As part of the German R&T project “Manned- Unmanned Teaming” (MUM-T), Elektroniksystem- und Logistik-GmbH (ESG) was assigned the task of investigating these concepts and the options for their realization. The focus of the investigation was initial operation capability within a narrow time frame concentrating on German Army Aviation helicopters. The paper focuses on the results achieved by ESG and begins with a short project overview. In the main part a representative MUM-T mission based on a personnel recovery mission is presented. The mission was demonstrated by ESG in close cooperation with German Army Aviation Combat Development Division (Ger AAV CDD). Beside operational aspects, technical aspects will be discussed. The lecture will close with a short outlook on the next steps, bringing MUM-T missions into service. 相似文献
32.
We present a technique for inducing functional programs from few, well chosen input/output-examples (I/O-examples). Potential applications for automatic program or algorithm induction are to enable end users to create their own simple programs, to assist professional programmers, or to automatically invent completely new and efficient algorithms. In our approach, functional programs are represented as constructor term rewriting systems (CSs) containing recursive rules. I/O-examples for a target function to be implemented are a set of pairs of terms (F(ii),oi) meaning that F(ii)—denoting application of function F to input ii—is rewritten to oi by a CS implementing the function F. Induction is based on detecting syntactic regularities between example terms. In this paper we present theoretical results and describe an algorithm for inducing CSs over arbitrary signatures/data types which consist of one function defined by an arbitrary number of rules with an arbitrary number of non-nested recursive calls in each rule. Moreover, we present empirical results based on a prototypical implementation. 相似文献
33.
Real-life appraisal interviews conducted by 92 manager-subordinate pairs were studied intensively. Reactions of subordinates were systematically obtained before and after their appraisal interviews and the proceedings in the actual interviews were carefully documented by trained Os. Measures of subsequent performance improvement realized as a result of the appraisal interviews were taken 12 wk. later. The results indicated that a manager's attempts to assist a subordinate by pointing up improvement needs were likely to be perceived by the subordinate as threatening to his self-esteem and to result in defensive behavior. The greater the threat, the less favorable the attitude toward the appraisal system and the less the subsequent constructive improvement in job performance realized. These reactions were strong to the extent that the subordinate had relatively low occupational self-esteem. Some practical implications for appraisal practices are cited. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
Evaldiney R. Monteiro Emanuel N. Macêdo João N.N. Quaresma Renato M. Cotta 《International Communications in Heat and Mass Transfer》2009
An analytical integral transformation of the thermal wave propagation problem in a finite slab is obtained through the generalized integral transform technique (GITT). The use of the GITT approach in the analysis of the hyperbolic heat conduction equation leads to a coupled system of second order ordinary differential equations in the time variable. The resulting transformed ODE system is then numerically solved by Gear's method for stiff initial value problems. Numerical results are presented for the local and average temperatures with different Biot numbers and dimensionless thermal relaxation times, permitting a critical evaluation of the technique performance. A comparison is also performed with previously reported results in the literature for special cases and with those produced through the application of the Laplace transform method (LTM), and the finite volume-Gear method (FVGM). 相似文献
35.
Scattering centers model (SCM) is usually considered for modeling target backscattered signal in high-resolution radar. In this case the impulse response of each scattering center is represented by a time-delayed Dirac pulse. Some of most popular superresolution imagery techniques, such as MUSIC or ESPRIT, are well-matched to this model. Under this hypothesis, they outperform Fourier-based techniques in terms of both spatial and dynamic resolutions. However, the behavior of real-world targets is often very different from that of the SCM. Indeed, their reflectivity function is not confined just to several perfectly localized scattering centers, but it can be rather approximated by a set of scattering regions having different spatial extent. SCM becomes then inappropriate and the superresolution methods may provide unexpected results. Furthermore, the amplitude information is difficult to interpret in this case. In this paper we propose an extension of two superresolution methods, MUSIC and ESPRIT, to cope with extended scattering centers (ESC). According to this model, the impulse response of an ESC is not a Dirac pulse, but a window of finite support. Besides the position, the size (spatial extent) of this window is also recovered. This additional information about the target structure can be used for increasing ATR (automatic target recognition) accuracy and robustness. 相似文献
36.
Emanuel A.E. Cyganski D. Orr J.A. Shiller S. Gulachenski E.M. 《Power Delivery, IEEE Transactions on》1990,5(2):676-686
The measured values of current harmonics at a staged high-impedance ground fault on sandy soil are presented. The measured low-frequency spectrum is compared with current harmonics recorded continuously for one week at the substation. This comparison was carried out to determine to what extent 120 Hz and 180 Hz components can be used to help detect a high-impedance fault. The field measurements are supported by a simple theoretical model and laboratory measurements. It is concluded that, for the studied feeder, detection of high-impedance arcing faults may be possible by monitoring of the second-harmonic current 相似文献
37.
Akihide Kuwabara Xiang Gao Ralf Riedel Emanuel Ionescu Yuichi Ikuhara 《International Journal of Applied Ceramic Technology》2023,20(1):190-196
Transition-metal-doped silicon nitride ceramics have attracted much attention as gate materials for semiconductors because of their electrical properties as well as chemical and thermal stability. The present study aims to clarify the defect structures of Hf-doped β-Si3N4 by theoretical calculations and scanning transmission electron microscopy (STEM). First-principles calculations based on a hybrid functional method were performed. It was found that Hf dopants are mainly substituted for the Si sites and can be occasionally located at interstitial sites in the lattice of β-Si3N4. The substitution sites of Hf dopants predicted by the first-principles calculations were also confirmed by the high-resolution STEM images. 相似文献
38.
39.
This paper reports on the reliability of single-point measurements for harmonic pollution cost allocation. Simulated results give the correlation between the cost and four physical electrical quantities that can be measured at the end-user bus: harmonic active power; harmonic apparent power; total harmonic current squared; and nonfundamental apparent power squared. The nonfundamental apparent power squared produced the best correlation, with errors less than 5% 相似文献
40.
Gehring William J.; Gratton Gabriele; Coles Michael G.; Donchin Emanuel 《Canadian Metallurgical Quarterly》1992,18(1):198
Investigated the effects of probability information on response preparation and stimulus evaluation. Eight Ss responded with 1 hand to the target letter H and with the other to the target letter S. The target letter was surrounded by noise letters that were either the same as or different from the target letter. In 2 conditions, the targets were preceded by a warning stimulus unrelated to the target letter. In 2 other conditions, a warning letter predicted that the same letter or the opposite letter would appear as the imperative stimulus with .80 probability. Correct reactions times (RTs) were faster and error rates were lower when imperative stimuli confirmed the predictions of the warning stimulus. Probability information affected (1) the preparation of motor responses during the foreperiod, (2) the development of expectancies for a particular target letter, and (3) a process sensitive to the identities of letter stimuli but not to their locations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献