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141.
《Journal of Quantitative Spectroscopy & Radiative Transfer》1986,35(2):127-130
A test has been made of various potentials for the Ar-H2 van der Waals molecule by calculating linewidths and energies for rotational predissociated levels, using a body-fixed distortion approximation. A multiconfigurational self-consistent treatment, including correction for basis set superposition errors, was found to be adequate for a study of rotational predissociation of the Ar-H2 complex. 相似文献
142.
《Solid State Communications》1986,60(3):275-276
We investigate the temperature dependence of electrical conductivity of SI-GaAs. We have shown that the surface conductivity obeys the Berthelot type of dependence, the bulk component, on the other hand, fulfills the Arrhenius dependence. 相似文献
143.
《Journal of Molecular Spectroscopy》1986,117(2):283-291
Computer-assisted analysis of hundreds of double resonance signals from CF2Cl2 has yielded constants for the hot bands ν6 + ν4 − ν4 of CF235Cl2 and CF235Cl37Cl and ν6 + ν5 − ν5 of CF235Cl2. It has also produced the first experimental data over the ν6 fundamental of CF237Cl2. 相似文献
144.
《Journal of Molecular Spectroscopy》1986,116(1):101-107
The ν3 (CF stretching) band of the CH2F radical was observed with Doppler-limited resolution, by using infrared diode laser spectroscopy with Zeeman and discharge current modulation. The CH2F radical was generated directly in a multiple reflection absorption cell by the electrical discharge in CH2FCOOCH3. The observed spectrum was analyzed to yield the band origin of 1170.4165(6) cm−1 with one standard error in parentheses, in addition to the rotational constants, centrifugal distortion constants, and spin-rotation interaction constants in the v3 = 1 state. 相似文献
145.
《中国化学快报》2020,31(9):2347-2352
Lithium-sulfur (Li-S) batteries have received extensive attention due to their high theoretical specific energy density. However, the utilization of sulfur is seriously reduced by the shuttle effect of lithium polysulfides and the low conductivity of sulfur and lithium sulfide (Li2S). Herein, we introduced bimetal-organic frameworks (Co/Zn-ZIF) derived cobalt and nitrogen-doped carbons (Co/N-C) into Li-S batteries through host design and separator modification. The Co/N-C in Li-S batteries effectively limits the shuttle effect through simultaneously serving as polysulfide traps and chemical catalyst. As a result, the Li-S batteries deliver a high reversible capacity of 1614.5 mAh/g and superior long-term cycling stability with a negligible capacity decay of only 0.04% per cycle after 1000 cycles. Furthermore, they have a high area capacity of 5.5 mAh/cm2. 相似文献
146.
147.
《European Journal of Operational Research》1997,101(2):245-260
Approximate solutions for discrete stochastic optimization problems are often obtained via simulation. It is reasonable to complement these solutions by confidence regions for the argmin-set. We address the question how a certain total number of random draws should be distributed among the set of alternatives. Two goals are considered: the minimization of the costs caused by using a statistical estimate of the true argmin, and the minimization of the expected size of the confidence sets. We show that an asymptotically optimal sampling strategy in the case of normal errors can be obtained by solving a convex optimization problem. To reduce the computational effort we propose a regularization that leads to a simple one-step allocation rule. 相似文献
148.
Xiaowei Song Gaoyang Li Lei Yang Luxiao Zhu Chunping Hou Zixiang Xiong 《Entropy (Basel, Switzerland)》2022,24(8)
With the development of convolutional neural networks, the effect of pedestrian detection has been greatly improved by deep learning models. However, the presence of pseudo pedestrians will lead to accuracy reduction in pedestrian detection. To solve the problem that the existing pedestrian detection algorithms cannot distinguish pseudo pedestrians from real pedestrians, a real and pseudo pedestrian detection method with CA-YOLOv5s based on stereo image fusion is proposed in this paper. Firstly, the two-view images of the pedestrian are captured by a binocular stereo camera. Then, a proposed CA-YOLOv5s pedestrian detection algorithm is used for the left-view and right-view images, respectively, to detect the respective pedestrian regions. Afterwards, the detected left-view and right-view pedestrian regions are matched to obtain the feature point set, and the 3D spatial coordinates of the feature point set are calculated with Zhengyou Zhang’s calibration method. Finally, the RANSAC plane-fitting algorithm is adopted to extract the 3D features of the feature point set, and the real and pseudo pedestrian detection is achieved by the trained SVM. The proposed real and pseudo pedestrian detection method with CA-YOLOv5s based on stereo image fusion effectively solves the pseudo pedestrian detection problem and efficiently improves the accuracy. Experimental results also show that for the dataset with real and pseudo pedestrians, the proposed method significantly outperforms other existing pedestrian detection algorithms in terms of accuracy and precision. 相似文献
149.
In this study, we employed the first-principles calculation to investigate the structural, electronic and transport properties of 1T-HfSe2 and 1T-PtSe2 transition metal dichalcogenides, and further explain why they share the same 1T (octahedral) layered structure but exhibit very different electronic and transport properties. There are two underlying concepts: the degree of interlayer bond ionicity and the number of 5d valence electrons of transition metal. The high degree of Hf-Se bond ionicity not only gives rise to the indirect energy gap of HfSe2 bulk and thin films, but also results in the weak Se-Se vdW interlayer coupling to further restrict the electron transport only within a HfSe2 layer. On the other hand, the modulation of metallic/semiconducting property of PtSe2 bulk and thin films can be understood by the significant vdW interlayer coupling, which induces charge redistribution of Se atom and allows electrons to transport within a PtSe2 layer as well as cross neighboring layers. Finally, our transport calculation for 1T-HfSe2/1T-PtSe2 bulks and monolayers suggests the great electron transport within Hf-Se/Pt-Se layer but suppresses/allows electron from neighboring layers. The robust two-dimensional characteristic of 1T-HfSe2 and the metal-to-semiconductor transition of 1T-PtSe2 may provide more knowledge for future application in nanoelectronic and optoelectronic devices. 相似文献
150.
A spike in a set of bioburden data can be considered a bioburden number or numbers that are several times greater in value than the average value of the data set. A spike is not considered a manifestation of a quality issue, but a consistent component of product bioburden that should be taken into account in establishing the minimum acceptable dose in the radiation sterilization process. Rather than a subjective approach, statistical techniques were used to determine when a bioburden number or numbers represent spikes in a set of bioburden data. Bioburden data taken from a cross section of different products over a few months were analyzed. Results of the study identified spikes when the spike bioburden was approximately three or more times the average bioburden for the data set. In those cases where bioburden spikes were identified, use of the spike bioburden rather than the average bioburden increased the sterilization dose by up to 10%. 相似文献