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911.
Zhuang Bohan Shen Chunhua Tan Mingkui Chen Peng Liu Lingqiao Reid Ian 《International Journal of Computer Vision》2022,130(9):2081-2102
International Journal of Computer Vision - In this paper, we propose to train binarized convolutional neural networks (CNNs) that are of significant importance for deploying deep learning to mobile... 相似文献
912.
Yan Qingsen Gong Dong Shi Javen Qinfeng van den Hengel Anton Shen Chunhua Reid Ian Zhang Yanning 《International Journal of Computer Vision》2022,130(1):76-94
International Journal of Computer Vision - Ghosting artifacts caused by moving objects and misalignments are a key challenge in constructing high dynamic range (HDR) images. Current methods first... 相似文献
913.
Adaptive curve headlights swivel with steering input and are linked to reduced insurance claims and improved visual performance. This study assessed glare experienced from adaptive curve high-intensity discharge (HID), fixed (non-swiveling) HID and fixed halogen headlights – all tested in low beam mode. Twenty participants rated glare from vehicles’ headlights using the DeBoer visual discomfort scale as a test driver drove towards them from five approaches on a test track. Participants rated the fixed halogen condition as less glaring than the adaptive curve and fixed HID conditions. There was no significant difference in ratings between the HID low-beam conditions. Collapsing across roadway approaches, the mean subjective ratings for the fixed halogen, adaptive curve HID and fixed HID low-beam conditions indicated ‘satisfactory’ levels of glare. Differences between subjective ratings were supported by illuminance data. Differences among the three low-beam systems appear minor, relative to their differences from a benchmark high-beam condition.
Practitioner Summary: Insurance data indicates reduced claims associated with adaptive curve lighting. The current effort was to study how such lighting affects discomfort glare of oncoming drivers relative to conventional headlights. Participants rated halogen headlights as less glaring than fixed and adaptive curve HID low beams. Differences among systems were small and associated with acceptable levels of discomfort glare. 相似文献
914.
This paper studies sensor fault detection using a game theoretic approach. Sensor fault detection is considered as change point analysis in the coefficients of a regression model. A new method for detecting faults, referred to as two-way fault detection, is introduced which defines a game between two players, i.e. the fault detectors. In this new strategic environment, assuming that the independent states of the regression model are known, the test statistics are derived and their finite sample distributions under the null hypothesis of no change are derived. These test statistics are useful for testing the fault existence, as well as, the pure and mixed Nash equilibriums are derived for at-most-one-change and epidemic change models. A differential game is also proposed and solved using the Pontryagin maximum principle. This solution is useful for studying the fault detection problem in unknown state cases. Kalman filter and linear matrix inequality methods are used in finding the Nash equilibrium for the case of unknown states. Illustrative examples are presented to show the existence of the Nash equilibriums. Also, the proposed fault detection scheme is numerically evaluated via its application on a practical system and its performance is compared with the cumulative sum method. 相似文献
915.
We consider classical estimators for a class of physically realizable linear quantum systems. Optimal estimation using a complex Kalman filter for this problem has been previously explored. Here, we study robust H∞ estimation for uncertain linear quantum systems. The estimation problem is solved by converting it to a suitably scaled H∞ control problem. The solution is obtained in the form of two algebraic Riccati equations. Relevant examples involving dynamic squeezers are presented to illustrate the efficacy of our method. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
916.
Rapid synthesis,electrical, and mechanical properties of polycrystalline Fe2AlB2 bulk from elemental powders 下载免费PDF全文
Ning Li Yuelei Bai Shuai Wang Yongting Zheng Fanyu Kong Xinxin Qi Rongguo Wang Xiaodong He Andrew Ian Duff 《Journal of the American Ceramic Society》2017,100(10):4407-4411
Polycrystalline Fe2AlB2 bulk including minor Al2O3 is synthesized by reactive hot pressing from Fe, Al, and B powders at 1200°C and 30 MPa for 30 minutes, with a relative density of 96%. The present approach enables a markedly reduced holding time compared with previous studies. The derived Fe2AlB2 shows an electrical resistivity of 2.27±0.01 μΩ·m, Vickers hardness of 10.2±0.2 GPa, flexural strength of 232±25 MPa, compressive strength of 2101±202 MPa, fracture toughness of 5.4±0.2 MPa·m1/2 and work of fracture of 117±12 J/m2. No dominant indentation cracks are observed, indicating that Fe2AlB2 may be quite damage tolerant. Interestingly, a noncatastrophic failure is present in the SENB test, with a high work of fracture. The energy‐absorbing mechanisms in inhibiting crack formation are delamination and pullout of Fe2AlB2 grains. 相似文献
917.
Composition and temperature dependence of structure and piezoelectricity in (1−x)(K1−yNay)NbO3‐x(Bi1/2Na1/2)ZrO3 lead‐free ceramics 下载免费PDF全文
Dawei Wang Fayaz Hussain Amir Khesro Antonio Feteira Ye Tian Quanliang Zhao Ian M. Reaney 《Journal of the American Ceramic Society》2017,100(2):627-637
Lead‐free piezoceramics with the composition (1?x)(K1?yNay)NbO3‐x(Bi1/2Na1/2)ZrO3 (KNyN‐xBNZ) were prepared using a conventional solid‐state route. X‐ray diffraction, Raman spectroscopy, and dielectric measurements as a function of temperature indicated the coexistence of rhombohedral (R) and tetragonal (T) phase, typical of a morphotropic phase boundary (MPB) as the BNZ concentration increased and by adjusting the K/Na ratio. High remnant polarization (Pr=24 μC/cm2), piezoelectric coefficient (d33=320 pC/N), effective piezocoefficient ({d_{33}^*}=420 pm/V), coupling coefficient (kp=48%), and high strain (S=0.168%) were obtained at room temperature, but significant deterioration of Pr, {d_{33}^*}, and kp were observed by increasing from room temperature to 160°C (17.5 μC/cm2, 338 pm/V, and 32%, respectively) associated with a transition to a purely T phase. Despite these compositions showing promise for room‐temperature applications, the deterioration in properties as a function of increasing temperature poses challenges for device design and remains to be resolved. 相似文献
918.
Alisha Van Zandvoort David R. Lapen Ian D. Clark Corey Flemming Emilia Craiovan Mark D. Sunohara Ronda Boutz Natalie Gottschall 《Nutrient Cycling in Agroecosystems》2017,109(2):115-132
Controlled tile drainage (CTD) can benefit the environment and crop production. However, CTD has the potential to increase soil greenhouse gas (GHG: CO2, CH4, N2O) emissions by increasing soil water contents and elevating field water levels. A paired-field (CTD and uncontrolled tile drainage (UTD)) approach was used to compare soil GHG emissions for silt loam corn, soybean, and forage fields under CTD and UTD management in eastern Ontario, Canada during a drier and a wetter growing season. A total of five field pairs were examined. Soil GHG emissions directly over tile drains (OT) and between tile drains (BT) in the CTD fields were also assessed. Average soil GHG emissions did not significantly differ (p > 0.05) for CTD and UTD field pairs, except for CO2 emissions (greater emissions from UTD fields) among two field pairs studied (forage in the drier growing season and soybean in the wetter growing season), and N2O emissions from a soybean field pair in the wet growing season (greater emissions from CTD field). Significantly higher soil water contents in the UTD forage field may have augmented CO2 fluxes there. There were some significantly higher N2O (in the wetter growing season) and CO2 emissions (in both growing seasons) BT relative to OT locations in some fields; but these differences were not translated significantly to other BT and OT site comparisons. The wetter growing season examined resulted in greater average daily soil CO2 fluxes overall, but similar CH4 and N2O fluxes for soybean fields compared to soybean fields in the drier growing season. Overall, there were no spatially or temporally systematic differences in GHG emissions among CTD and UTD field pairs, or among BT and OT locations in CTD fields. 相似文献
919.
Dr. Andrea E. Prota Katja Bargsten Dr. Mariano Redondo‐Horcajo Prof. Dr. Amos B. Smith III Chia‐Ping H. Yang Hayley M. McDaid Prof. Dr. Ian Paterson Prof. Dr. Susan B. Horwitz Dr. José Fernando Díaz Prof. Dr. Michel O. Steinmetz 《Chembiochem : a European journal of chemical biology》2017,18(10):905-909
Microtubule‐stabilizing agents (MSAs) are widely used in chemotherapy. Using X‐ray crystallography we elucidated the detailed binding modes of two potent MSAs, (+)‐discodermolide (DDM) and the DDM–paclitaxel hybrid KS‐1‐199‐32, in the taxane pocket of β‐tubulin. The two compounds bind in a very similar hairpin conformation, as previously observed in solution. However, they stabilize the M‐loop of β‐tubulin differently: KS‐1‐199‐32 induces an M‐loop helical conformation that is not observed for DDM. In the context of the microtubule structure, both MSAs connect the β‐tubulin helices H6 and H7 and loop S9–S10 with the M‐loop. This is similar to the structural effects elicited by epothilone A, but distinct from paclitaxel. Together, our data reveal differential binding mechanisms of DDM and KS‐1‐199‐32 on tubulin. 相似文献
920.
Carl J. Nicholls Brian Boswell Ian J. Davies M. N. Islam 《The International Journal of Advanced Manufacturing Technology》2017,88(9-12):2429-2441
Monotonic fault progression is an important assumption for a number of prognostic models. This assumption can be violated through human intervention and self‐healing and result in non-monotonic degradation data which not only increases the uncertainty but also may cause model failure. Methods to analyze and handle non-monotonic degradation in repairable systems are practically nonexistent in the literature. In this research, we intend to consider repairable systems in which self‐healing is possible and human interventions are desirable. We presented a novel example of self-healing for fatigue cracks analyzed by acoustic emission. The aim of the present paper is to initiate a new research area on using non-monotonic measures in degradation-based prognostics. However, this research is not a review of trend analysis techniques, and therefore, there are more techniques to be considered or developed in future studies. In effect, trend analysis should be considered as an integral part of prognostics and health management. This study considers trend analysis for three classes of data, (1) prognostic parameters, (2) degradation waveform, and (3) multivariate data. A new form of crest factor is introduced for more effective waveform analysis of non-monotonic data. In addition, two algorithms are introduced to treat non-monotonic trend. The prognostic model used in this research does not produce results without treating non-monotonicity. These kinds of algorithm have promising potential to treat non-monotonicity and deal with arbitrary stationary noise in degradation data. 相似文献