(Other)sistering: Black Women Education Leadership Faculty Aligning Identity, Scholarship, and Practice Through Peer Support and Accountability

This inquiry offers insight into how Black women assistant professors traverse the challenging journey toward tenure while acknowledging their connection to their students and communities, research, teaching, and service. By employing a phenomenological approach and utilizing Black feminist thought and community cultural wealth as conceptual and theoretical frameworks, this research advances scholarship identifying commonalities across Black women’s experiences. Further, we offer implications for how the academy can support Black women and other professionals from marginalized populations. Findings include how Black women assistant professors develop and create dynamic support systems amongst themselves to combat the multiple marginalizations of their positionality in the academy––a place where they are historically “outsiders.”

A Vibrational Signal Fault Diagnosis Rule Extraction Method Based on DST-ACI Discriminant Criterion

A fault diagnosis rule extraction method oriented to machine foot signal based on dynamic support threshold and association coefficient interestingness (DST-ACI) discriminant criterion is proposed in this paper. The new method includes three main innovations. First, the feature state coding method based on K-means clustering fully takes into account the imbalanced distribution of signal feature values due to the noise interference, and divide the signal feature values into several range intervals to generate the feature state code. Second, the frequent feature pattern mining method based on dynamic support threshold (DST) discriminant criterion can dynamically adjust support threshold according to the frequency of the feature states in each candidate pattern. Third, the fault diagnosis rule extraction method based on the association coefficient interestingness (ACI) discriminant criterion introduces a new metrics called ACI to evaluate the correlation between the pattern and the fault. Four types of fault simulation experiments were carried out, and the performance of the DST-ACI method was tested using the collected vibration signal. The results show that compared with the coding method based on equal-width discretization or equal-density discretization, the accuracy of the transactional dataset generated by the feature state coding method based on K-means clustering is higher. Compared with the frequent feature pattern mining method based on the constant support threshold criterion, the pattern mined by the DST-based criterion has generally higher support. Compared with the existing confidence-lift-based and confidence-improint-based fault diagnosis rule extraction frameworks, the positive correlation between the feature states and the fault type of the rules extracted based on the DST-ACI framework is generally stronger.

A Novel MapReduce-based Algorithm for Association Rules Mining

AR (Association rule) is considered to be one of the models for data mining. With the growth of datasets, conventional association rules are not suitable for big data mining, which has aroused a large number of scholars' interest in algorithm innovation. This study aims to design an optimization parallel association rules mining algorithm based on MapReduce, named as PMRARIM-IEG algorithm, to deal with problems such as the excessive space occupied by the CanTree (CanTreeCanonical order Tree), the inability to dynamically set the support threshold, and the time-consuming data transmission in the Map and Reduce phases. Firstly, a structure called SIM-IE (similar items merging based on information entropy) strategy is adopted for reducing the space occupation of the CanTree effectively. Then, a DST-GA (dynamic support threshold obtaining using genetic algorithm) is proposed to obtain the relatively optimal dynamic support threshold in the big data environment. Finally, in the process of MapReduce parallel, a LZO (Lempel-Ziv-Oberhumer) data compression strategy is used to compress the output data of the Map stage, which improves the speed of the data transmission. We compared the PMRARIM-IEG algorithm with other algorithms on five datasets, including Wikipedia , LiveJournal, com-amazon, kosarak, and webdocs. The experimental results obtained demonstrate that the proposed algorithm, PMRARIM-IEG, not only reduces the space and time complexity, but also obtains a well-performing speed-up ratio in a big data environment.

Dynamic Support Stiffness of Motorized Spindle Bearings under High-speed Rotation

The rotor operating stiffness of high-speed motorized spindles (HSMSs) is key to machining accuracy. Because HSMSs are difficult to load due to their high speeds, a contact loading device was developed to test rotor operating stiffness. The dynamic support stiffness of the front/rear bearings (DSSB) is the main factor affecting the rotor operating stiffness. Two novel experimental schemes for measuring the DSSB are proposed: 1) indirect measurement—by analysing deformation displacements at two points on the external loading rod of the HSMS, and 2) direct measurement—by eddy current sensors installed near the front/rear bearings. Based on the experimental device and two experimental schemes, the influences of working-condition parameters on the DSSB were tested. The results show that the proposed experimental device and two experimental schemes can effectively and accurately measure rotor operating stiffness and DSSB at speeds of up to 30,000 rpm. However, because the tapered connection gap between the loading rod and rotor increases the measured deformation displacement, the DSSB measured by the indirect measurement scheme was relatively small. The DSSB decreases with speed and increases with radial force and working temperature. This study provides a new experimental basis for the quality inspection of finished HSMSs and the verification of theoretical bearing stiffness models.

New thermal constraints for the Anatolian lithosphere from Curie depth point and Pn tomography

<p><span>Continental deformation can be </span><span>described in two end-member approaches: </span><span><em>block</em></span><span> (or microplate) and </span><span><em>continuum </em></span><span>models</span><span>. The first considers a strong lithosphere with deformation localized in fault zones. For </span><span>t</span><span>he latter, however,</span><span> the lithosphere is weak</span><span> and deforms as a thin viscous sheet. The Anatolia – Aegean domain represents both continuum and plate-like deformation. Furthermore, </span><span>r</span>ecent modeling studies suggest a dynamic support mechanism of the Anatolian plateaus, with dynamic topography estimates ranging from 1 to 3 km for various crustal models and geodynamic scenarios, although the gravity and crustal thickness data support predominant Airy isostasy. The solution to both intricacies relies on the thermal structure of the crust and the lithosphere. Available thermal considerations stem from either the uppermost mantle velocity structure or thermal modeling with assumptions on radiogenic heat production and boundary conditions. Yet, homogeneous and independent constraints on the lithospheric structure are scarce. We aim to contribute to this knowledge gap by providing Curie Point Depths (CPDs), which corresponds to the depth at which rock-forming minerals lose their magnetization at the Curie temperature, ~580 <sup>o</sup>C.<br><br>R<span>esolution of deep magnetic sources requires spectral methods with large windows, which reduce the CPD resolution. Moving & overlapping smaller windows have been used in order to increase the resolution, but these introduce spectral leakage and bias. </span>In previous studies, subjective wavenumber ranges of the magnetic anomaly spectra were used, often combined with wrong scaling factors between map units and the equations. This resulted in generally erroneous CPD estimates. Furthermore, CPD uncertainties have often been unquantified for the study area. <span>We use a wavelet transform method, which overcomes the artifacts due to segmentation of magnetic signal to finite windows, results in higher spatial resolution as well as enabling uncertainty estimation. </span>We used as large an area as possible for constraining the edge effects away from the study area. The resultant CPD map spatially correlates well with low Pn velocity areas, locations of volcanoes, and thermal springs.</p>

Cooling of the Northern Hemisphere triggered by Northeast Atlantic opening at the Eocene – Oligocene Transition

<p>The Eocene – Oligocene Transition (~33.7 million years ago), marks the largest step transformation within the Cenozoic cooling trend, and is characterized by a sudden growth of the Antarctic ice sheets. The role of changes in oceanic basin configuration and the evolution of key oceanic gateways in triggering these climatic variations remains disputed. Here we implement a new state-of-the-art paleogeography model in the Norwegian Earth System Model (NorESM-F) to investigate the effect of oceanic gateway changes on the Eocene – Oligocene climate. We run different cases using realistic max/min depth configurations of the Atlantic – Arctic oceanic gateways, the Tethys Seaway, and the Southern Ocean gateways, and investigate the ocean and climate sensitivity to these changes. In addition, we run separate simulations investigating the impact on the carbon cycle. The models show that changes in the Atlantic – Arctic gateways (i.e. Greenland – Scotland Ridge and the Fram Strait) cause the most significant changes in ocean circulation and climate compared to the Southern Ocean gateways or the Tehthys Seaway. The Iceland mantle plume caused depth variations on the Greenland – Scotland Ridge at this time, and our model result indicate that variations in dynamic support from the Iceland plume could have played a key role in the Eocene – Oligocene climate transition. Essentially, reduced dynamic support from the plume deepen the Greenland – Scotland Ridge and cause freshwater leakage from the Arctic Ocean which inhibits deep water formation in the North Atlantic, reducing the AMOC and ultimately cool the Northern Hemisphere.</p>

Design & Analysis of Dynamic Response in Hydrolic Equipment Working with Heavy Loads

Hydraulic system has benefits over pneumatic or electric systems, especially when heavy loads are involved, or when very smooth and precise position or pressure control is required. Hydraulic actuators have several advantages including the fact that they produce less heat and electrical interference at the machine than do electric actuators. A simulation model of the support was established to determine the dynamic responses of the hydraulic support under dual impacts from its roof and shield beams, and the column and balance jack were replaced using a spring-damper system. Analysis of poses was performed and dynamic support responses were obtained.